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  • Inorganic Chemistry  (7,874)
  • Cell & Developmental Biology  (1,658)
  • Weizen
  • Wiley-Blackwell  (9,532)
  • 1975-1979  (5,249)
  • 1925-1929  (4,283)
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  • Wiley-Blackwell  (9,532)
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  • 101
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    New York, NY : Wiley-Blackwell
    Journal of Morphology 159 (1979), S. 393-425 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Branchial food traps are regions of specialized secretory tissue in the tadpole pharynx, where suspended food particles are trapped in mucus.Light and scanning electron microscopy were used to study branchial food traps from larvae of ten anuran families (36 species). Most anuran larvae from “advanced” (suborder Neobatrachia) families (e.g., Hylidae, Ranidae, Bufonidae) have distinct secretory pits at the posterior margins of the branchial food traps and secretory ridges elsewhere on these surfaces. The apices of columnar PAS-positive, secretory cells are exposed on the floors of the secretory pits or in rows at the tops of the secretory ridges (secretory zone).Tadpoles from most “archaic” (suborder Archaeobatrachia) families (Ascaphidae, Discoglossidae and Pelobatidae) either lack secretory pits, or have them poorly defined. They also lack secretory ridges but have columnar, mucus-secreting cells whose apices are exposed in a seemingly random fashion in the branchial food traps. Rhinophrynus (Archaeobatrachia: Rhinophrynidae) has secretory ridges, but the apices of secretory cells are not arranged in rows at the tops of the ridges; instead they erupt singly or in small clusters on the epithelial surface, in a pattern similar to that in Ascaphus, the discoglossids and the pelobatids. It is proposed that the generalized condition for the branchial food trap mucosa is one where the apices of secretory cells are exposed haphazardly on a flat epithelium and the derived condition is one where the surface is organized into ridges. The morphology of the branchial food traps in Rhinophrynus suggests that, phylogenetically, ridges preceded the coalescing of secretory cell apices into distinct rows.Pipidae and Microhylidae have unique patterns in the gross and microanatomy of their branchial food traps specific to their families.Branchial food trap morphology relates to diets of tadpoles as well as to taxonomy. Obligate macrophagous (e.g., carnivorous) tadpoles, irrespective of family, tend to have reduced branchial food traps, regularly lack secretory ridges and, in extreme cases, lack columnar mucus-secreting cells. Obligate microphagous forms (midwater suspension feeding of Xenopus, microhylids and Agalychnis), have straight parallel secretory ridges with narrow secretory zones and shallow troughs between the ridges.Secretory ridges may help to form mucus strands in which food particles are trapped, but they are not essential for planktonic entrapment. The hydrodynamic implications of the various topographic patterns remain unclear.
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  • 102
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    New York, NY : Wiley-Blackwell
    Journal of Morphology 160 (1979), S. 1-5 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Tactile hairs, small chemoreceptor pegs, thick-walled chemoreceptors, thin-walled chemoreceptors of several types, coeloconic sense organs and campaniform sense organs are present on the flagellum of a stonefly, Allocapnia recta (Claassen).
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  • 103
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    New York, NY : Wiley-Blackwell
    Journal of Morphology 160 (1979) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 104
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    Journal of Morphology 161 (1979), S. 23-38 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Glycogen metabolism has been studied during the development of the early chick embryo, at the cytochemical and ultrastructural levels. Two waves of glycogen synthesis and breakdown have been found. In the first, free clusters of glycogen particles are synthesized at late oogenesis. These clusters are found later in invaginations of the membrane of vesicles containing a floc-cular material (FLOV). The glycogen clusters are degraded there during ovulation and the first hours in the oviduct. The second wave of glycogen synthesis begins before cleavage, reaching a maximum at mid-uterine age. This second wave occurs in another type of vesicle (GLYV), which eventually disintegrates releasing free clusters of glycogen granules. This glycogen is degraded in membranous structures containing a floccular material, as in the first wave of degradation. The degradation ends at the late uterine stages, and at the same time numerous ribosomes are formed. This period corresponds to area pellucida formation, which probably depends on the energy liberated during the second wave of glycogen degradation.
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  • 105
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    Journal of Morphology 161 (1979), S. 79-109 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The hindgut of the semi-terrestrial tardigrade, Milnesium tardigradum was examined with light and electron microscopy. The hindgut consists of a cloaca and an anterior hindgut. It is delineated anteriorly by the pylorus into which four Malpighian tubules empty and posteriorly, by a broad cloacal slit. A single oviduct enters the hindgut at the junction between the cloaca and the anterior hindgut. Two pairs of muscles insert on the cloaca and anterior hindgut respectively. Electron microscopic observations demonstrate that the anterior hindgut is a specialized transporting epithelium. The luminal surface is covered by a thin layer of cuticle which penetrates into channel-like invaginations. Numerous mitochondria are concentrated apically. The basal and lateral surfaces are also folded. The cells are joined apically by deep tight junctions and a simple basal lamina lines the entire hindgut. The cloaca which receives the contents of the gut and Malpighian tubules as well as gametes of the reproductive tract is a transitional organ that exhibits several characteristics of the hypodermis and anterior hindgut. The cuticle of the cloaca changes sequentially from the complex structure of the integument to a simple layer of the anterior hindgut. The function of the hindgut is discussed with emphasis on the possible response of the anterior hindgut to a hypoosmotic habitat, evaporative water loss during the induction of anhydrobiosis and low oxygen tension.
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  • 106
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    Journal of Morphology 161 (1979), S. 123-143 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Blood follicles of the earthworm Amynthas are hemoglobin-containing, sac-like dilatations of blood vessels which connect to the general circulation. Grape-like clusters of follicles are found posterior to the pharynx, among tufts of micronephridia, and single follicles are located among cells of the pharyngeal gland. In Lumbricus, follicles take the form of simple swellings and irregular-shaped diverticula of nephridial capillaries.The fundamental structure of the wall of follicles and of vessels in both genera is the same and consists of two layers: an extracellular vascular lamina and an outer (coelomic) covering of smooth muscle-like myoperithelial cells. Hemocytes may be free and circulating or they may facultatively attach to the vascular lamina as littoral cells, constituting an incomplete endothelium-like surface. Hemocytes that appear to be in the process of attaching or detaching are rounded, while adherent cells are flattened and elongate. Free and littoral hemocytes actively endocytose packets of circulating extracellular hemoglobin.Hemocytes within follicles possess radiating cell processes which also endocytose hemoglobin. Although these cells were presumed to secrete hemoglobin, staining with 3,3′-diaminobenzidine confirms the presence of hemoglobin only within pinosomes and not within protein-synthesizing or packaging organelles. The presence of hemosiderin-like bodies suggests that follicular hemocytes catabolize hemoglobin.Blood follicles apparently provide a means of significantly increasing cell-surface area for hemoglobin processing, without substantially increasing the volume and pumping load of the circulatory system.
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  • 107
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    Journal of Morphology 161 (1979), S. 211-219 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The nucleoli of rat liver cells duplicate in great detail the lifelong series of reorganizational changes encountered in kidney and intestinal epithelial cells. The ultrastructural components of the large, loosely organized polymorphous nucleoli, which are dominant in the rapidly multiplying stem cells of embryos, are readily accessible for chemical activities. Smaller, more compact amphinucleoli are dominant in more mature cells, which were characterized by Smetana ('70) as “idling” cells, showing slowly continuing ribosome formation and RNP synthesis. In older cells bipartite nucleoli become dominant and are reorganized in increasing numbers from the younger amphinucleoli. These, however, are not replaced in equal numbers from the shrinking pool of polymorphs of young cells which have greatly reduced mitotic potential. Paralleling the shifts in dominant nucleolar types, the high level of protein synthesis declines in older cells not only in the quantity of proteins synthesized but also in kinds of enzymes produced. These fail to meet the structural and functional requirements of aging cells leading ultimately to the onset of age-related degenerative changes. Again it is noted that separation of the karyosomal DNA from the plasmosomal RNA-protein complex of the nucleolus may lead to possible breakdown of the DNA-dependent RNA-protein transcription system ultimately bringing protein synthesis to a very low level in the senescent animal.
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  • 108
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The heart of Crocodylus porosus is described, and deemed to be typical of living crocodilians after examination of the hearts of Alligator mississippiensis, Caiman crocodilus ssp., Crocodylus johnstoni and Crocodylus n. novaeguineae. Some inconsistencies between the anatomy and supposed patterns of blood flow are discussed. The crocodilian heart is compared with, and seen as an advancement of, the heart of non-crocodilian reptiles. The varanid ventricle is re-examined, as it appeared to contain many crocodilian features, along with the ophidian characteristics described previously. The broad similarities within the three groups are interpreted as adaptations towards a high pressure systemic circulation. Consequently varanids and snakes show the same left and right ventricles, as do crocodilians and birds. The evolution of the complete interventricular septum of crocodilians and birds appears to have involved three major trends: firstly, the development of a high pressure left ventricle and the fusion of most of the combined atrio-ventricular valve to the ostium of the right systemic artery; secondly, a line in which right to left shunting became gradually redundant and the vertical septum was completed to the aortico-pulmonary septum (giving rise to the avian ventricle); and thirdly, a line in which right to left shunting became increasingly important, and the vertical septum completed to the interaortic septum (giving rise to the crocodilian ventricle). Perhaps the crocodilian ancestry included a crocodile that was far more aquatic than any extant species.
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  • 109
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    Journal of Morphology 161 (1979), S. 337-345 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In considering primate and hominoid phylogeny, the fundamental position assigned to opossums is explained partially by the characteristic morphology of their hands and feet. One of the main functional features of the human hand is the ability to make a stabilized arch of the finger. Because the extensor assembly plays a key role in establishing an arched finger, the extensor systems of the digits of both the hands and feet were studied in two species of opossum, Philander opossum and Didelphis marsupialis.In the foot, two extensor tendons join in each toe to form one tendinous plate, which inserts onto the base of the second phalanx. Lumbricals join this plate along the tibial side, and interosseus insertions are found, although a true interosseus wing is lacking. At the proximal interphalangeal level, a terminal tendon takes its origin from this tendinous plate. This terminal tendon is oval in cross-section and contains elastic structures. Oblique bands arise from this terminal tendon and run proximally along the proximal interphalangeal joint inserting onto the base of the first phalanx. There are elastic structures in the flexor tendon on the dorsal side near its site of insertion.In the hand, the main extensor tendons are arranged differently and the interossei contribute substantially to the extensor assembly. Otherwise, the extensor assembly of the hands and feet are quite similar. The function of the so-called paratendinous intravaginal flexors is discussed as are evolutionary aspects of the extensor assembly.
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  • 110
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    Journal of Morphology 162 (1979) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 111
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    Journal of Morphology 162 (1979), S. 211-219 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: New schemata of the liver are presented to discuss the combination of the three kinds of liver lobules known until today in a chalk-talk-manner. Terminology is also discussed. Further investigations are needed involving the construction and the vascular pattern of compound lobules of the three individial lobules of the liver in different species.
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  • 112
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    Journal of Morphology 161 (1979), S. 323-335 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The blood supply of muscle spindles was studied in serial cross sections in macaque, cat, rabbit, guinea pig, mouse and pigeon muscles which had been incubated in a medium containing 3,3′ diaminobenzidine. Lumina of blood vessels were recognized by the reaction product that was localized within erythrocytes. The outer capsule was well vascularized, but few or no capillaries were seen in the periaxial space. The inner spindle capsule, which closely invests the axial bundle, was rarely contacted by periaxial capillaries at the equator and juxtequator. Capillaries occurred more frequently adjacent to intrafusal fibers at the polar region and beyond the end of the outer capsule. Shorter diffusion distances and, usually, higher capillary densities were found at the polar region than at the spindle midsection. This suggests that transcapillary exchange at the polar segment is nearer to conditions prevalent in extrafusal muscle than elsewhere in the spindle, provided the inner and outer capsules are not less permeable at the poles than at the midsection. Differences in blood supply among mammalian species appear to be related to receptor size.
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  • 113
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    Journal of Morphology 162 (1979), S. 67-75 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The role of dying cells in the optic stalk in relation to retinal fiber migration was investigated in the chick embryo. Cell death was analysed at various stages of development by counting pycnotic nuclei and also by the Gomori acid phosphatase reaction, while nerve fibers were visualised by the Bodian method. A wave of cell death, beginning in the neural retina at stage 18 and advancing with time through the stalk towards the diencephalon, occurred simultaneously or slightly prior to differentiation and migration of ganglion cell axons. Cell death stopped and gliogenesis occurred in the stalk after penetration by retinal fibers. Cell death occurred in the stalk even when fiber penetration was prevented by optic cup ablation. In this case, necrosis ensued until almost complete degeneration of the stalk, usually within three days after the operation, and gliogenesis did not occur. As the stalk degenerated, its cells became heavily pigmented. These observations suggest that the onset of cell death in the optic stalk is determined prior to and independently of retinal fiber penetration. On the other hand, cessation of cell death and subsequent gliogenesis occur only in the presence of ingrowing optic fibers.
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  • 114
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Somatic portions of gonads in two phanerozonian sea-stars, Ctenodiscus crispatus and Hippasteria phrygiana, were similar in all aspects of gross structure and histology seen previously in both forcipulate and spinulosan asteroids. For the first time, detailed ultrastructural observations have been made of cells and tissues that reveal several features believed to be of universal occurrence in the gonads of asteroids. These include flagellated-collar cells in the visceral peritoneum and other coelomically derived epithelia, muscular-flagellated-collar cells in the visceral peritoneum and genital coelomic (perihaemal) sinus, the digestion of collagen fibers by cells in the connective tissue layer, and the intimate relationship of the genital haemal sinus and the entire germinal epithelium.Structural and functional compartmentalization are discussed in relation to major activities of the gonad throughout the annual reproductive cycle. The distinctive ultrastructure and current generation of flagellated-collar cells found in the visceral peritoneum are analyzed relative to their role in nutrient transport to gonadal tissues. The single flagellum of each flagellated-collar cell beats in coordination with those on neighboring cells to produce extremely rapid, oriented currents of coelomic fluid. The form of beating in an individual flagellum is planar, and the resulting synchronized activity of many adjacent flagella is non-metachronal; both of these characteristic aspects of current production have, thus far, been encountered together only in the Echinodermata. Flagellated-collar cells are efficient in generating currents which mix contents of the coelomic fluid, and they can presumably supply themselves with nutrients. It is concluded that nutrients so obtained are generally not passed through the wall of the gonad to the germinal epithelium and, as a result, have little to do with nutrition of somatic and germinal cells of the germinal epithelium. Alternatively, well-developed genital portions of the haemal system of the sea-star are advanced as the major channels supplying nutrients to germinal epithelia during gametogenesis.
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  • 115
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    Journal of Morphology 162 (1979), S. 221-247 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The light and electron microscopic structure of the pineal complex of the domestic goose was studied. The complex is tubulofollicular but there is no direct connection between the constituent system of ducts and the third ventricle of the brain. Within the pineal, blood vessels accompanied by sympathetic nerve bundles are confined to the connective tissue. Other nerve fibers and occasional nerve cell bodies, however, do occur among the pineal cells.Three basic pineal cell types were distinguished: (1) elongate epithelial cells which are arranged around follicles and ducts and resemble degenerate photo-receptor cells; (2) intramural supportive cells which are interspersed with elongate epithelial and intramural supportive cells; and (3) small supportive cells which lie between the bases of the elongate epithelial and intramural supportive cells. The follicular structure, vascularization, presence of secretory granules, and the nature of the elongate epithelial cells indicate that the pineal complex is primarily endocrine though a possible photoreceptive function cannot be ignored. Vesicles, 100-300 and 40-100 nm wide, were found within nerves and intramural supportive cells. The larger vesicles, present in pineals collected in the night, probably contain peptidic hormones. The smaller vesicles present in both day and night samples probably contain aminergic hormones.
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  • 116
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Cell surface coats are important in adhesion and other cellular activities. The lamprey egg possesses a surface coat that has been divided into two morphologically and functionally distinct regions. The amorphous apical tuft forms a cap over the animal pole, while the elaborately-textured adhesive coat covers the ventral two-thirds of the egg. This latter area is composed of saccules that form rosettes over the egg surface and is derived from the remains of specialized follicular cells which break down during ovulation. The adhesive qualities of these coats may be inhibited or abolished by various proteins and sulphydryl-blocking agents, thereby implicating, as a possible source of this adhesion, classes of acid and sulphated glycoproteins and glycosaminoglycans which occur on the egg surface.
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  • 117
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    Journal of Morphology 162 (1979), S. 413-424 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Two-toed sloths have evolved a wrist complex that includes the following traits: (1) diminution and distal migration of the pisiform, with a loss of contact with the ulna; (2) reduction of the distal end of the ulna to a styloid process; and (3) extremely reduced contact between the ulna and triquetrum. These traits were proposed by Lewis ('65, '74) to be indicative of brachiating habits and to be a unique adaptation of the Hominoidea. Cartmill and Milton ('77) recently found a similar complex in the wrists of the lorisines. Very similar adaptations of the wrist among the Hominoidea, lorisines, and two-toed sloths clearly refute contentions of Lewis and strengthen the hypothesis of Cartmill and Milton that the traits common to those animals are due to similar slow, cautious, but acrobatic locomotion.
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  • 118
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Although a number of recent studies describe the facilitation of limb regeneration by electrical and other forms of stimulation, little is known of innate regenerative capacity in the mammalian limb. The present report describes spontaneous regenerative responses following subtotal forelimb amputation in the young white rat. In one group of animals the forelimb was amputated through the lower humerus and the skin sutured closed. In a second group, adjacent muscle tissue still attached to bone at its origin(s) was interposed between the cut surface of the humerus and the skin. Among animals of the first group (skin closure only) bone growth and limb regenerative responses were generally not observed. Animals of the second group displayed significant elaborations of cartilage and bone at the limb terminus. The appearance and subsequent modification of these tissues suggest that some capacity for limb regeneration exists innately in the young rat and can be more readily evoked than has been recognized heretofore. It is concluded that extant and forthcoming reports of electrically stimulated skeletal tissue growth, repair and regeneration among eutherial mammals should be examined to determine whether reported responses to stimulation represent advances beyond what might be expected from innate replacement processes alone.
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  • 119
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    Journal of Morphology 160 (1979), S. 17-31 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The minimum number of secretion products used by the spiders Araneus trifolium and Argiope trifasciata to construct their orb webs has been established by selective enzyme digestion and histochemical staining, as well as differential isotope localization in these webs. Three fiber types are present in the webs: (a) a major fiber found throughout the web, (b) a minor fiber found only in radial threads, and (c) the core fibers of the sticky spiral thread. Three nonfibrous secretions are found on these fibers. These include a water soluble viscid coating of the sticky spiral and two adhesives which fasten the threads of the web together; one found only at junctions of sticky spiral and radial threads and the other at all other thread connections. The possible glandular sources of these secretions are discussed.
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  • 120
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    Journal of Morphology 160 (1979), S. 75-101 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The tesserate pattern of endoskeletal calcification has been investigated in jaws, gill arches, vertebral arches and fins of the sharks Carcharhinus menisorrah, Triaenodon obesus and Negaprion brevirostris by techniques of light and electron microscopy. Individual tesserae develop peripherally at the boundary between cartilage and perichondrium. An inner zone, the body, is composed of calcified cartilage containing viable chondrocytes separated by basophilic contour lines which have been called Liesegang waves or rings. The outer zone of tesserae, the cap, is composed of calcified tissue which appears to be produced by perichondrial fibroblasts more directly, i.e., without first differentiating as chondroblasts. Furthermore, the cap zone is penetrated by acidophilic Sharpey fibers of collagen. It is suggested that scleroblasts of the cap zone could be classified as osteoblasts. If so, the cap could be considered a thin veneer of bone atop the calcified cartilage of the body of a tessera. By scanning electron microscopy it was observed that outer and inner surfaces of tesserae differ in appearance. Calcospherites and hydroxyapatite crystals similar to those commonly seen on the surface of bone are present on the outer surface of the tessera adjacent to the perichondrium. On the inner surface adjoining hyaline cartilage, however, calcospherites of variable size are the predominant surface feature. Transmission electron microscopy shows calcification in close association with coarse collagen fibrils on the outer side of a tessera, but such fibrils are absent from the cartilaginous matrix along the under side of tesserae. Calcified cartilage as a tissue type in the endoskeleton of sharks is a primitive vertebrate characteristic. Calcification in the tesserate pattern occurring in modern Chondrichthyes may be derived from an ancestral pattern of a continuous bed of calcified cartilage underlying a layer of perichondral bone, as theorized by Ørvig (1951); or the tesserate pattern in these fish may itself be primitive.
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  • 121
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    Journal of Morphology 160 (1979), S. 169-193 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A detailed account is given of the structure of the gills of Clarias batrachus, Heteropneustes (= Saccobranchus) fossilis, Channa punctata, Monopterus (= Amphipnous) cuchia and Boleophthalmus boddaerti, based upon light and electron microscopy. In all five species the basic organization into primary and secondary lamellae is apparent but the latter are very much more modified in Monopterus.Three main layers separate the water and blood on the surface of the secondary lamellae. The outer epithelium is usually two layered but may be multilayered close to the origin of the secondary lamellae from the gill filament. The basement membrane is relatively thin and a middle dense layer containing collagen fibrils separates two clear layers. The pillar cells, so characteristic of secondary lamellae, are present in all except Monopterus and flanges from these cells surround the blood channels with the exception of the marginal channels. The latter are lined by endothelial cells which line all the blood channels of Monopterus.The overall thickness of the three layers comprising the water/blood barrier ranges from 1.5 to 13 microns. A number of modifications to this basic organization can be related to the degree of dependence of the different species on air-breathing.Boleophthalmus is the only species commonly found in brackish water and its secondary lamellae have well developed lymphoid spaces between two layers of the epithelium. Special densely-stained regions of the pillar cell flanges were also present in this fish and may have a supporting function.
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  • 122
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    Journal of Morphology 160 (1979), S. 195-207 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Serial coronal sections of the teeth and their surrounding tissues in the agamid lizard, Uromastix aegyptius, were examined with the light microscope in order to determine how these structures change as the teeth wear. Because new teeth are added only at the posterior end of the tooth row and older teeth are not replaced, the series of sections included the youngest as well as the oldest teeth. Two types of changes occur as the teeth become older: bone under the teeth changes from cancellous to compact, and the pulp chamber of the tooth is obliterated. Although the labial surface of the dentary lacks a periosteal covering and some of the bone lacks any covering at all, it remains functional throughout the life of the animal.
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  • 123
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    Journal of Morphology 160 (1979), S. 275-297 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The nervous system of the planula larva of Anthopleura elegantissima consists of an apical organ, one type of endodermal receptor cell, two types of ectodermal receptor cells, central neurons and nerve plexus. Both interneural and neuromuscular synapses are found in the nerve plexus.The apical organ is a collection of about 100 long, columnar cells each bearing a long cilium and a collar of about 10 microvilli. The cilia of the apical organ are twisted together to form an apical tuft. The ciliary rootlets of the apical organ cells are extremely long, reaching to the basal processes of the cells adjacent to the mesoglea.All three types of sensory cells are tall and slender in profile and are identified by the presence of one or more of the following features: microtubules, small vesicles, membrane-bound granules and synapses. The interneurons are bipolar cells with somas restricted to the aboral end, adjacent to the apical organ. All synapses observed are polarized or asymmetrical.A diagram including all the elements of the nervous system is presented and the possible functions of the nervous system are discussed in relation to larval behavior.
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  • 124
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    Journal of Morphology 160 (1979), S. 323-343 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Comparison of germ cells in male and female embryos of the arrhenotokous thrips, Haplothrips verbasci, yields the following observations: A mean of 11 cleavage energids enter the posterior pole plasm of the egg after the sixth cleavage division and apparently become pole cells when they take up polar granules in their cytoplasm. The cells proliferate asynchronously prior to and during anatrepsis to yield a mean of 36 germ cells in male embryos and 31 in females. Visible sexual differentiation of germ cells begins during germ band elongation and is completed shortly after the appearance of appendages. Female germ cells are larger than those of the males and may contain two nucleoli. The germ cells separate into two groups just before katatrepsis and mesodermal cells collect about these to form the primary epithelial sheaths of the gonads and the primordia of the gonoducts shortly after revolution is completed. Each gonad contains a mean of 13 germ cells in male embryos and 7 in females - a number that persists until mitosis resumes after hatching. During ketatrepsis, a mean of 11 germ cells in male embryos and 2.6 in females fail to be enclosed within the gonads, become dispersed in the yolk and perhaps transform into vitellophages.Germ cell development in H. verbasci embryos resembles similar events taking place in psocid embryos, providing additional evidence for a close phylogenetic relationship between Thysanoptera and Psocoptera.
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  • 125
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    Notes: A sensory papilla is described in the eyestalk of the crayfish Astacus leptodactylus during the last embryonic stages and during larval stages by light microscopy. This region was also investigated with the scanning electron microscopy, which showed sensory hairs in the postmolt adult; they disappear during intermolt and premolt. Simultaneous cyclic changes in hair papillae are observed in the hypodermis. The possibility of a chemoreceptive function is discussed.
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  • 126
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    Journal of Morphology 161 (1979), S. 53-77 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: Formation of nuclear envelopes during the last cleavage mitosis and the formation of the cell membranes during the cellularization of the blastoderm have been studied ultrastructurally in the blowfly egg. Dense bodies arising from yolk granules by budding could contain membrane material destined to be incorporated into the new membranes of the blastoderm. The presence of transitional structures indicates that these bodies can be converted into dark multivesicular bodies. Large amounts of endoplasmic reticulum are found around the mitotic nuclei. Clusters or branched chains of vesicles associated with this are interpreted as evidence for the formation of endoplasmic reticulum by the breakdown of dark multivesicular bodies. Nuclear envelopes of mitotic daughter nuclei probably originate from endoplasmic reticulum. The egg contains both intranuclear and extranuclear annulate lamellae.The main events of cytokinesis are furrow initiation and cell membrane growth during the slow first phase, but probably only cytokinetic movement during the rapid second phase. On the assumption that cell membrane growth occurs by incorporation of complete membrane pieces, the addition of coated vesicles and/or light multivesicular bodies is definitely most probable. Some intermediate profiles indicate that light and dark multivesicular bodies are related. The membrane needed for second phase cytokinesis could well be provided by the unfolding of surface microvilli and protuberances of the furrow canal.
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  • 127
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    Journal of Morphology 159 (1979), S. 29-47 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Early spermatids of the onychophoran Peripatopsis capensis are spherical cells with a centrally located nucleus, numerous mitochondria, Golgi complexes, microtubules and two centrioles. During spermiogenesis, Golgi vesicles migrate to one side of the cell where they form a tight aggregate, which is later shed. The mature spermatozoon has no acrosome. Several mitochondria fuse to form a middle piece containing three large mitochondria. Nucleus and middle-piece elongate, presumably under the influence of helically twisted microtubules. Outside this set of microtubules a continuous layer of endoplasmic reticulum cisternae is formed which separates the interior portion of the cell from an external cytoplasmic rim, which is later shed. Outside the 9 + 2 complex, the tail presents nine accessory microtubules, and a peripheral layer of microtubules beneath the plasma membrane. The enforcement of the tail structure may be related to the fertilization biology of this animal, which is by “hypodermal” impregnation.
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    Journal of Morphology 159 (1979) 
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  • 129
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    Notes: The three major salivary glands of the monotreme echidna are described. The parotid is a typical serous gland with tubulo-acinar secretory endpieces and a well-developed system of striated ducts. The mandibular gland, although light microscopically resembling a mucous gland, secretes very little glycoprotein. Its cells are packed instead with serous granules, resembling in fine structure the “bull's eye” granules in the mandibular gland of the European hedgehog Erinaceus europaeus. The sublingual glands secrete an extremely viscous mucous saliva. Expulsion of this saliva through the narrow ducts is probably aided by contraction of the extensive myoepithelial sheaths surrounding the secretory tubules. Application of the glyoxylic acid induced fluorescence method failed to demonstrate adrenergic innervation in any of the glands.
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    Journal of Morphology 159 (1979) 
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  • 131
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    Notes: Single-element and/or rosette strain gages were bonded to mandibular cortical bone in Galago crassicaudatus and Macaca fascicularis. Five galago and eleven macaque bone strain experiments were performed and analyzed. In vivo bone strain was recorded from the lateral surface of the mandibular corpus below the postcanine tooth row during transducer biting and during mastication and ingestion of food objects.In macaques and galagos, the mandibular corpus on the balancing side is primarily bent in the sagittal plane during mastication and is both twisted about its long axis and bent in the sagittal plane during transducer biting. On the working side, it is primarily twisted about its long axis and directly sheared perpendicular to its long axis, and portions of it are bent in the sagittal plane during mastication and molar transducer biting. In macaques, the mandibular corpus on each side is primarily bent in the sagittal plane and twisted during incisal transducer biting and ingestion of food objects, and it is transversely bent and slightly twisted during jaw opening. Since galagos usually refused to bite the transducer or food objects with their incisors, an adequate characterization of mandibular stress patterns during these behaviors was not possible. In galagos the mandibular corpus experiences very little transverse bending stress during jaw opening, perhaps in part due to its unfused mandibular symphysis.Marked differences in the patterns of mandibular bone strain were present between galagos and macaques during the masticatory power stroke and during transducer biting. Galagos consistently had much more strain on the working side of the mandibular corpus than on the balancing side. These experiments support the hypothesis that galagos, in contrast to macaques, employ a larger amount of working-side muscle force relative to the balancing-side muscle force during unilateral biting and mastication, and that the fused mandibular symphysis is an adaption to use a maximal amount of balancing-side muscle force during unilateral biting and mastication.These experiments also demonstrate the effects that rosette position, bite force magnitudes, and types of food eaten have on recorded mandibular strain patterns.
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  • 132
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    Notes: Five regions are recognized in the accessory glands of the Mediterranean flour moth, Anagasta kuehniella (Zeller), on the basis of cellular morphology and aggregates of secretory material in the lumen. Some variation is found in each of the posterior four regions, especially the third one. In the most anterior region (region 1) the epithelium is composed of a single type of cell, while in each of the other regions there are two classes of cells. The cells of region 1 and one class in each of the other four regions are fairly typical exocrine cells with extensive rough endoplasmic reticula. Secretion is primarily via Golgi-derived vesicles. Apocrine secretion in the form of sloughing off of the apical cytoplasm probably also occurs in all regions but is most prominent in the posterior two regions. One class of cells is very similar in morphology in each of the posterior four regions though their secretory products form characteristic aggregates in the lumen. The second class of cells (foliate cells) occurring in the posterior four segments is most notably characterized by elongate apical projections that extend out into the lumen. The apical projections contain large quantities of glycogen, some microtubules, and, in some cases, many minute mitochondria. The membrane content of the projections is also very high. In the anterior regions, the membranes are mostly fused in pairs and typically form multilayered whorls. Fusion and whorl formation decrease in the posterior regions. The cytoplasm of the foliate cells has a high organelle content including many lysosomes and mitochondria. The latter exhibit considerable polymorphism, with particular forms occurring in the different regions of the glands. The apical projections of the foliate cells are detached during copulation, presumably as the result of nervous stimulation, and become a part of the ejaculate. Replenishment of all secretory material, including the apical projections, occurs after copulation.
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    Journal of Morphology 161 (1979), S. 185-210 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The cellular populations present in dorsomedial cortex in the snakes Constrictor constrictor, Natrix sipendon and Thamnophis sirtalis are described at the light microscopic level using Nissl and Golgi preparations as well as at the ultrastructural level. This area plays a central role in cortical organization in snakes by participating in major commissural and association projections.Systematic analyses of Golgi preparations indicate that five populations of neurons are present in dorsomedial area and have a preferential laminar distribution. Layer 1 stellate cells have somata positioned in the center of the outermost cortical layer, layer 1. Their dendrites are confined to this layer. Double pyramidal cells have their somata loosely packed in layer 2. Their dendrites bear a moderate population of spines, ascending through layer 1 to the pial surface and descending partially through layer 3. Some double pyramidal cells have somata displaced downwards into the upper third of layer 3. These neurons closely resemble the layer 2 double pryamidal cells. Layer 3 stellate cells have somata positioned in the middle third of layer 3. Their dendrites extend in all directions throughout layer 3 and through layer 2 into layer 1. Finally, horizontal cells have their somata positioned deep in layer 3, near the ventricle, and dendrites aligned concentric with the ventricle.Comparison of the organization of the known afferents to dorsomedial area with the distribution of the five cell types suggests that the laminations of both afferent fibers and dorsomedial neurons places specific neuronal populations in synaptic contact with specific sets of afferents.
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    Journal of Morphology 161 (1979), S. 177-183 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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    Notes: The morphology of a sex pheromone-producing gland found in the abdomen of Drosophila grimshawi males was studied by light and electron microscopy. This gland, consisting of two intra-anal lobes, contains cells that resemble those of other insect pheromone glands. However, in contrast to many other insect pheromone glands that release pheromone through the cuticle, cells of the intra-anal lobes secrete into a canaliculi-duct system that empties into the anal region. The liquid secretory product flows along the surface of the intra-anal lobes and is brushed onto the substrate by fingerlike projections on the lobes' surfaces.
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    Journal of Morphology 161 (1979), S. 241-256 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: The ultrastructure of the sacculus and lagena of a moray eel, Gymnothorax sp., was investigated using scanning and transmission electron microscopy. Particular emphasis was placed on the orientation of the sensory hair cells and on the ultrastructure of the sensory cells. The ciliary bundles on the sensory hair cells are of several types, each having a different size relationship between the kinocilium and stereocilia. The cell bodies of the sensory cells are similar to the mammalian type II sensory cell. There were no apparent differences in the cell bodies between sensory cells with different ciliary bundles.Hair cell orientation patterns on the saccular and lagenar maculae differ from patterns found in other fishes. The posterior side of the saccular macula in Gymnothorax has cells oriented dorsally and ventrally, as is typical in other non-ostariophysan species. The anterior end of the saccular macula has alternating groups of anteriorly and posteriorly oriented cells, a situation that differs from the more typical pattern in which anteriorly oriented cells are found on the ventral side of the macula while posteriorly oriented cells cover the dorsal side of the macula. The orientation of cells on the lagena includes ventral cells that are located above a group of dorsally oriented cells. In many other non-ostariophysans, ventrally oriented cells are generally posterior to the dorsally oriented cells.
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    Journal of Morphology 162 (1979) 
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    Journal of Morphology 162 (1979), S. 175-209 
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    Notes: The present investigation has examined the ultrastructural differentiation of the genital ducts of both sexes of fetal mice. The emphasis of observations was placed on the phenomenon of morphogenetic cytolysis, particularly during the critical periods of Wolffian duct stabilization and Mullerian duct involution.Both developing and regressing genital ducts evidence extensive cytolysis. Autophagy appears to be the mechanism of morphogenetic change in the developing male Wolffian duct. Autophagy, heterophagy, and degeneration in situ are all prominent cytolytic activities in female Wolffian duct involution. The developing female Mullerian duct undergoes extensive morphogenetic remodeling by the mechanisms of autophagy, heterophagy, and degeneration in situ. In the male Mullerian duct, autophagy, heterophagy, and degeneration in situ are also prominent. In addition, whole degenerated epithelial cells are extruded from the duct early in regression which may be related to the transformation of periductal mesenchymal cells into an “epithelioid cell cuff” which does not form around the regressing Wolffian duct. The formation of this mesenchymal condensation surrounding the duct is also accompanied by the protrusion of Mullerian epithelial cell cytoplasm into the mesenchymal cells. These observations may evidence a complex epithelial-mesenchymal interaction occurring during male Mullerian duct involution.
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    Journal of Morphology 162 (1979), S. 311-311 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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  • 139
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    Journal of Morphology 162 (1979), S. 343-359 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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    Notes: The morphology and carbohydrate histochemistry of ten teleostean intestines are compared. Although there is an absence of regional differentiation seen in higher vertebrates, specializations in some species occur in the form of intestinal swellings, pyloric ceca and recta, the latter separated by a valve. The intestinal lumen is lined by a simple columnar epithelium interspersed with goblet cells; multicellular intestinal glands are absent. Thick basement membranes seen in centrarchids and Perca flavescens closely resemble the stratum compactum found in the lamina propria of esocids. Granular cells, which vary in number from species to species, are often seen in the mucosa and submucosa but less frequently in the muscularis. In species with intestino-rectal valves, a rectum is easily defined by the abrupt appearance of lower mucosal folds, more goblet cells and a thicker muscularis. In the remaining species the above features appear gradually in the distal intestine. Goblet cells show species variations in localization of epithelial mucosubstances, which in broad terms are recognized as sulfomucins, sialomucins and neutral mucosubstances. In both proximal and distal intestines the majority of goblet cells contain sialomucin although small amounts of sulfomucin are also often present. In species without intestino-rectal valves, no changes in carbohydrates occur between proximal and distal intestines. The possible significance of the heterogeneous character of digestive tract mucosubstances is discussed.
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    Journal of Morphology 162 (1979), S. 425-451 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The gross morphology, histology and ultrastructure of the canary's incubation patch and the ventral apterium from which it arises are described. The apterium is vascularized by pectoral, external mammary, incubation, and prepubic arteries. It is innervated by cutaneous branches of spinal nerves. It has a surface area of 6 cm2.Its epidermis is a stratified squamous epithelium with basal, intermediate, transitional and cornified layers. Cells in the stratum germinativum contain a normal array of organelles, but are characterized by tonofilaments, desmosomes and interdigitating surfaces. Cellular organelles disappear in the stratum transitivum and are replaced by large vacuoles and keratohyalin bands. Nonmyelinated nerve fibers are abundant in the stratum germinativum.The dermis consists of (1) an avascular layer of dense collagen subjacent to the epidermis and containing many nonmyelinated nerves, and (2) an underlying layer of areolar connective tissue containing blood vessels, lamellar corpuscles and nerves. A layer of coarse elastic fibers, reinforced by collagen and smooth muscle, separates the dermis from subcutaneous tissue.In contrast to the ventral apterium, the incubation patch is featherless and visibly hypervascular and edematous. Its epidermis is both hypertrophic and hyperplastic. Large spaces separate cells in the stratum germinativum. The visible hypervascularity is due to hyperemia and increased number and size of blood vessels in the dermis. Visible edema is due to the accumulation of fluid interstitially. Although no histological differences exist among various regions of the ventral apterium, such differences are present in the incubation patch.
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    Journal of Morphology 162 (1979), S. 453-463 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Haematoxylin, Alcian Blue-Chlorantine Fast Red (ABCR) and the Ralis osteoid-specific stain were employed to closely follow the histogenesis of the tibia of the embryonic chick so as to provide an accurate description of the onset of ossification.An overview of the major cytological events preceding osteogenesis in the tibia was obtained from hindlimbs of embryos of H. H. (Hamburger and Hamilton, '51) stages 16-26 (2.5-5 days of incubation) stained with ABCR. A description of the cytological changes in the periosteum as it develops from the perichondrium and an analysis of the timing of the onset of osteoid deposition was obtained from the tibiae of accurately aged and staged embryos of H. H. stages 28-32 (5.5-8 days). These tibiae were stained specifically for the detection of osteoid:the freshly-secreted, unmineralized product of fully-differentiated osteoblasts. The perichondrium transformed into a bi-layered periosteum at H. H. late stage 29 (6.5 days) while osteoid was first detected adjacent to the hypertrophic cartilage of H. H. stage 30 (6.5-7 days) tibial diaphyses.These results, correlated with the immunoflourescent studies of Von der Mark et al. ('76a,b), which revealed the presence of Type I (bone-type) collagen-synthesizing cells in the perichondria of tibiae from embryos of H. H. stage 28 (5.5-6 days), demonstrated that the onset of determination of cells for osteogenesis and the cytodifferentiation of the periosteum are not temporally coupled.
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  • 142
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    Notes: Exocrine dermal glands, comparable to the class 3 glandular units of insects, are found in the gills of the grass shrimp, Palaemonetes pugio. The dermal glands are composed of three cells: secretory cell, hillock cell and canal cell. Originating as a complex invagination of the apical cytoplasm of the granular secretory cell, a duct ascends through the hillock and canal cells to the cuticular surface. The duct is divisible into four regions: the secretory apparatus in the granular secretory cell, the locular complex, the hillock region within the hillock cell and the canal within the canal cell. A tubular ductule is contained within the latter two regions. As the ductule ascends to the cuticular surface, its constitution gradually changes from one of a fibrous material to one which possesses layers of epicuticle. During the proecdysial period, the ductule is extruded into the ecdysial space and this is followed by the secretion of a new ductule. Temporary ciliary structures, located near the secretory apparatus of the secretory cell, are associated with the extrusion and reformation of the ductule. Characterized only by a basal body and rootlets throughout most of the intermolt cycle, the ciliary organelles give rise to temporary axonemic processes which ascend through the ductule toward the ecdysial space at the onset of proecdysis. Subsequently, the old ductule is sloughed off and a new ductule is reformed around the ciliary axonemes. Following this reformation, the ciliary axonemes degenerate. The function of cytoplasmic processes, derived from the apical cytoplasm of the secretory cell, is also discussed.
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    Journal of Morphology 161 (1979), S. 309-321 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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    Topics: Biology , Medicine
    Notes: Rhabdomeric microvilli of the housefly were freeze-fractured (FF) and thin sectioned (TS) for ultrastructural examination. Ordered files of closely packed membrane particles (82 Å wide, 250 Å long) were seen (FF) on the microvillar membrane (usually E face). The long axis of each particle was canted about 45° to that of the microvillus. Occasionally particles in this array appeared on the P face. It is hypothesized that ordered particles may represent either a photopigment precursor stock, a second photolabile pigment, or the newly discovered sensitizing, UV-absorbing, photostable visual pigment. In the underlying membrane leaflet (P face) were found spherical (85 Å diameter) unoriented particles in a concentration of about 6,000/μm2. The size, shape and density of these structures are compatible with those of rhodopsin particles. These particles also covered the basal area of each microvillus. The findings from TS material were difficult to correlate with those from FF replicas. At high magnification the former showed that the plasma membrane of the transected microvillus is composed of spherical, hollow subunits (averaging 43 Å diameter), sometimes fused to form double, 86 Å units. These substructures were closely packed and continuous around the microvillus. This beaded plasma membrane, in rare cases, was doubled around the microvillus. In other instances the plasma membranes were continuous between neighboring microvilli. The physiological implications of these ultrastructural features are discussed.
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    Journal of Morphology 162 (1979), S. 17-36 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The optic tectum is a major subdivision of the visual system in reptiles. Previous studies have characterized the laminar pattern, the neuronal populations, and the afferent and efferent connections of the optic tectum in a variety of reptiles. However, little is known about the interactions that occur between neurons within the tectum. This study describes two kinds of interactions that occur between one major class of neurons, the radial cells, in the optic tectum of Pseudemys using Nissl, Golgi and electron microscopic preparations.Radial cells have somata which bear long, radially oriented apical dendrites from their upper poles and short, basal dendrites from their lower poles. They are divided into two populations on the basis of the distribution of their somata in the tectum. Deep radial cells have somata densely packed in the stratum griseum periventriculare. Their plasma membranes form casual appositions. Middle radial cells have somata scattered throughout the stratum griseum centrale and stratum fibrosum et griseum superficiale and do not contact each other. The apical dendrites of both populations of radial cells participate in vertically oriented, dendritic bundles. The plasma membranes of the dendrites in these bundles form casual appositions in the deeper tectal layers and chemical, dendrodenritic synapses within the stratum fibrosum et griseum superficiale. The synapses have clear, round synaptic vesicles and slightly asymmetric membrane densities. Thus, radial cells interact via both casual appositions and chemical synapses.These interactions suggest that radial cells may form a basic framework in the tectum. Because both populations of radial cells extend into the stratum fibrosum et griseum superficiale and stratum opticum, they may receive input from some of the same tectal afferent systems. Because the deep radial cells alone have somata and dendrites in the deep tectal layers, they may receive additional inputs that the middle radial cells do not. Neurons in the two populations interact via chemical dendrodendritic synapses, thereby forming vertically oriented modules in the tectum.
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    Journal of Morphology 162 (1979), S. 37-65 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Sialis flavilatera L. (Sialidae, Megaloptera) has telotrophic-meroistic ovarioles. The germ cells of the tropharium are organized into two distinct tissues, the central syncytium and the germ cell tapetum. The central syncytium consists of nurse cell nuclei embedded in a common cytoplasm which is rich in ribosomes and mitochondria. Cell membranes are totally absent. The germ cell tapetum surrounds the syncytium and consists of a monolayer of cells, each of which is connected with the central syncytium by an intercellular bridge. The oocytes differentiate from basal tapetum cells by previtellogenic growth. Their nutritive cords remain connected to the central syncytium by the intercellular bridge.Ovariole development starts soon after hatching with the immigration of germ cells into the ovariole-anlagen and is finished during pupal stages 23 months later. In apical regions of each tropharium, mitoses occur throughout larval life. The descendants enter the prophase of meiosis which lasts until pre-vitellogenesis; thus, a differential gradient of position and time is established. About 12 months after hatching, the central syncytium arises at the base of the tropharium from a membrane labyrinth in which intercellular bridges are entangled. Evidence is presented that endopolyploidization does not occur during germ cell differentiation.Finally, the results are compared with those found in Hemiptera and polyphage Coleoptera. The great diversities are interpreted as an indication for a polyphyletic origin of the telotrophic ovary.
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  • 146
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    Journal of Morphology 162 (1979), S. 163-173 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Five different types of sense organs were found on the antennal flagellum of Homadaula anisocentra. These were (1) tactile hairs; (2) thick-walled chemoreceptors; (3) thin-walled chemoreceptors of several kinds; (4) styloconic chemoreceptors and (5) small chemoreceptor pegs in shallow depressions. No coeloconic sense organs were seen.
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  • 147
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    Journal of Morphology 162 (1979), S. 249-273 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: To gain insight into the multiple functions of a complex biological structure, the morphology of the pharynx of the larva (ammocoete) of the lamprey Petromyzon marinus was investigated with scanning electron microscopy and histochemistry (PAS and Alcian blue). Features studied include the gills, the parabranchial chambers external to the gills, intrapharyngeal ciliary tracts, the ridged pharyngeal roof, the floor, and the intrapharyngeal taste buds. Significant findings are: (1) All (nonciliated) cells lining these structures are covered with microvilli or microridges. The pattern and packing density of these membrane features vary among different pharyngeal structures. The lumenar membranes of pharyngeal lining cells overlie a mucous prosecretion in the apical cytoplasm, suggesting that the microvilli/ridges on these membranes function to anchor mucus. (2) Patterns of microvilli/ridges on the gill respiratory lamellae differ among ammocoetes of different species. (3) Pharyngeal osmo-regulatory cells (“chloride cells”) could not be identified on the basis of the microvillus/ridge pattern. (4) Two types of ciliary tracts are present within the pharynx. One has tall (x= 13 μm) and densely packed cilia, whereas the other has shorter (x= 7 μm) and less densely packed ones. Because mucus covers both types of tracts their function appears to involve the transport of mucus. (5) Food particles were found on the lateral surfaces of the gill filaments and on the surfaces of the parabranchial chambers. It appears that goblet cells in the epithelia of these regions secrete mucus in which the particles are trapped.
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  • 148
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    Journal of Morphology 162 (1979), S. 327-341 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The structure of ankylotic teeth in Xenopus laevis was studied by light, transmission, and scanning electron microscopy as well as by microradiography in decalcified and undecalcified specimens.The mature teeth of Xenopus laevis are calcified from the crown to the base, fused to the jaw bone, and have no uncalcified area, such as a fibrous ring separating the tooth into the crown and pedicle. Microradiography shows that the mature tooth and jaw bone appear as an X-ray opaque area, except for the basal region of the dentine. This region is composed of an X-ray translucent area and an X-ray opaque thin layer on the lingual side of the translucent area. The mature tooth is composed of two differently calcified areas: (1) a highly calcified area, which makes up almost all of the tooth and contains a thin layer of the basal dentine on the lingual side, and (2) a lowly calcified basal dentine, which is fused to the jaw bone. Therefore, the lowly calcified area does not completely separate the dentine and jaw bone.Repeating banding patterns among the collagen fibrils differ among the dentine-forming area and the matrices of dentine and jaw bone. During the formation of ankylosis of the tooth germ, collagen bundles in the dentine-forming area accumulate directly on the surface of the jaw bone. Consequently, the mature teeth of Xenopus laevis fuse to the jaw bone directly without the mediation of the other structures.
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  • 149
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    Notes: Fine structure of the scales of Fundulus heteroclitus was examined by scanning and transmission electron microscopy. The concentric ridges of the scale surface were characterized by the presence of minute, highly calcified, denticles or tooth-like processes. Needle-shaped crystals of hydrox-yapatite were precipitated not only in the osseous layer but in the intimate lamellae of the fibrillary plate except in portions just below the grooves. The calcification of the osseous layer was observed to proceed by filling the matrix with patches of crystals. The fibrillary plate appeared to calcify by invasion of crystals from the upper calcified zone into spaces between collagen fibers.
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  • 150
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    Journal of Morphology 159 (1979), S. 89-115 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The retina and optic nerve of Strombus luhuanus were examined by transmission electron microscopy in order to provide an ultrastructural basis for their electrophysiological responses, described elsewhere. The retina exhibits a distinct rhabdomeric layer and layers of cell nuclei and neuropile. These layers are comprised predominantly of three cell types that can be readily distinguished on the basis of their shape, their nuclei and cytoplasmic inclusions such as vesicles and filaments. One type of cell, apparently a photoreceptor that depolarizes in response to photic stimulation, possesses a long distal segment with microvilli; such distal segments comprise the bulk of the rhabdomeric layer. A second cell type, which appears to be supportive in function, contains a bundle of tightly packed tonofilaments that extend across the retina from the capsule to the vitreous body; this cell is quite narrow except in the region near the rhabdomeric layer, where it is expanded and wraps around the other cell types. A third type of cell possesses many short microvilli that project from its apical end into the rhabdomeric layer; it may be a second type of photoreceptor or another type of neuron. The retina also contains bundles of cilia that appear to project from a possible fourth type of cell. The layer of neuropile contains numerous processes that exhibit a variety of vesicle types and structures generally associated with synapses; these appear to play a role in mediating inhibitory and excitatory interactions between the retinal neurons. The optic nerve exhibits two populations of fiber distinguishable on the basis of mean diameter. Fibers in these two populations apparently yield “on” and “off” discharges in response to photic stimulation of the eye.
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  • 151
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    Notes: When Aedes aegypti females first emerge as adults, their oocytes possess no yolk. The abdominal fat body cells contain large quantities of lipid, protein, and glycogen, and possess many free ribosomes, but have very little rough endoplasmic reticulum (RER). When the females are starved for four days, their oocytes form fine lipid and protein yolk endogenously, the latter being located mainly around the nucleus. The adipocytes in these fasted mosquitoes have greatly reduced amounts of lipid, protein and glycogen and contain many cytolysosomes. Seven hours after 4-day-starved females had fed on blood, their oocytes begin filling with exogenous protein yolk at the oolemma, and lipid arises endogenously throughout the ooplasm. At this hour, the fat cells have synthesized more RER than is seen in unfed controls. Twenty-four hours post blood meal, the follicle cells have secreted discrete endochorionic plaques onto the oolemma. At this period, the adipocytes are densely filled with RER, and show for the first time many Golgi bodies and protein inclusions. They have noticeably less glycogen than at seven hours. Within 48 hours after mosquitoes have fed on blood, the endochorion forms a continuous layer around the steadily enlarging egg which is synthesizing additional protein and lipid yolk. Concurrently, the adipocytes show a greatly increased amount of glycogen and a significant reduction of RER. By the sixtieth hour after the blood meal, the follicle cells are attenuated, and the fat cells have less RER and more glycogen than at 48 hours. The nurse cells steadily decrease in size during vitellogenesis and release material onto the micropyle.
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  • 152
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    Journal of Morphology 159 (1979), S. 221-232 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The electron microscopical structure of the type “B” cells in the rectal pad epithelium of Locusta is described. The type “B” cells occur singly in the distal region of the rectal pad epithelium. They are characteristically goblet shaped and join with contiguous type “A” or rectal pad cells, near the apical surface by means of a restricted region of septate desmosomes. Type “B” cells possess a microvillate apical membrane, with the villi arranged as a rosette overlying the apical inaginations of adjacent type “A” cells.Large numbers of microtubules and vacuoles of various sizes containing an assortment of inclusions are present in the apical region of the type “B” cells. Many of the microtubules insert distally on hemidesmosomes located in the apical plasma membrane. Rough endoplasmic reticulum and mitochondria are also present but neither are abundant. The possible significance of these findings is discussed.
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  • 153
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    Journal of Morphology 159 (1979), S. 233-243 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Patterns of tracheation in the abdominal central nervous system and the cerci of Acheta domesticus are described from whole mounts, and light and electron microscopy.The tracheal supply of the ganglia is derived from ventral longitudinal tracheal trunks which have segmental connections to the spiracels. Each abdominal ganglion is served by a single pair of tracheal trunks, except the terminal ganglion, which has two pairs. Within the ganglia, tracheoles occur principally in association with glia-rich areas of the neuropile. We suggest that the respiratory exchange may be concentrated in the cell bodies of neurons and glia. Each cercus has a tracheal supply in paralle with a large air sac which, it is suggested, serves to lighten the cercus, functions as a resonator for sound reception, or facilitates tidal flow of hemolymph and postecdysial expansion of the cercus. No tracheae run continuously between ganglia or between the terminal ganglion and the cerci, and they do not appear to have a potential role as a contact guidance pathway for cercal nerve growth.
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  • 154
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    Journal of Morphology 159 (1979), S. 311-329 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Normal development of the urostyle is described during late stages of metamorphosis in five species of anurans: Xenopus laevis (Daudin), Bufo americanus Holbrook, Pseudacris triseriata (Wied), Hyla chrysoscelis Cope, and Rana pipiens Schreber. The developing urostyle of all five species is composed of essentially the same cartilaginous elements: one pair of basidorsals above the notochord and the subtended hypochord. Among the five species there is variation in such details as the number of spinal nerve foramina and the degree of fusion of the basidorsals; however, both the hypochord and basidorsals are very similar in all five genera examined. Consideration of the literature suggests that contradictory descriptions of the developing urostyle result from (1) varied methods of study (alizarin-staining of whole specimens or serial cross-sections), (2) the variety of species examined, and (3) the particular stage of development of the tadpole described by an investigator.
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  • 155
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    Journal of Morphology 160 (1979), S. 165-168 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A biomechanical model of the jaw mechanism in some reptiles is presented. Symmetrical muscle activity that produces equal forces on both sides of the head is assumed. The model predicts the position of the most posterior bite point and offers a functional explanation for this prediction. Turtles are used to illustrate the idea.
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  • 156
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    Notes: A stress analysis of the primate mandible suggests that vertically deep jaws in the molar region are usually an adaptation to counter increased sagittal bending stress about the balancing-side mandibular corpus during unilateral mastication. This increased bending stress about the balancing side is caused by an increase in the amount of balancing-side muscle force. Furthermore, this increased muscle force will also cause an increase in dorsoventral shear stress along the mandibular symphysis. Since increased symphyseal stress can be countered by symphyseal fusion and as increased bending stress can be countered by a deeper jaw, deep jaws and symphyseal fusion are often part of the same functional pattern. In some primates (e.g., Cercocebus albigena), deep jaws are an adaptation to counter bending in the sagittal plane during powerful incisor biting, rather than during unilateral mastication.The stress analysis of the primate mandible also suggests that jaws which are transversely thick in the molar region are an adaptation to counter increased torsion about the long axis of the working-side mandibular corpus during unilateral mastication. Increased torsion of the mandibular corpus can be caused by an increase in masticatory muscle force, an increase in the transverse component of the postcanine bite force and/or an increase in premolar use during mastication.Patterns of masticatory muscle force were estimated for galagos and macaques, demonstrating that the ratio of working-side muscle force to balancing-side muscle force is approximately 1.5:1 in macaques and 3.5:1 in galagos during unilateral isometric molar biting. These data support the hypothesis that mandibular symphyseal fusion is an adaptative response to maximize unilateral molar bite force by utilizing a greater percentage of balancing-side muscle force.
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  • 157
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  • 158
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  • 159
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    Journal of Morphology 160 (1979), S. 299-321 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Nematode amphids are a pair of lateral cephalic sense organs, each comprising a group of sensory endings terminating in a cuticle-lined pit. In Syngamus trachea, a parasite of birds, each amphid is surrounded by two non-nervous supporting elements, a large gland cell basally and a smaller supporting cell anteriorly. The amphidial glands display high levels of secretory activity from five to six days postinfection. Secretory material is discharged through the lumen of the sense organ onto host tissue. The ultrastructure of amphids and amphidial glands has been investigated in newly moulted, immature and mature adults to trace the development of glandular activity and its effect on amphid-amphidial gland relationships. In newly moulted adults, the glands have very low levels of secretory activity and appear to act only as supporting cells to the amphids. As secretory activity increases, the gland cell membrane surrounding the sensory endings is elaborated into a reticulum which probably forms the secretory surface. In mature adults the amphid pit is swollen and filled with secretion; the sensory endings are relegated to the periphery of the lumen. It is suggested that amphidial glands develop from typical supporting cells, but acquire a new role possibly associated with parasite attachment.
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  • 160
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    Journal of Morphology 160 (1979), S. 209-221 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In D. melanogaster the cross-sectioned nerve of the leg-like antenna in the homeotic mutant Antennapedia was ultrastructurally compared with the nerves of the morphologically related second leg and the wild-type antenna. The nerves of the normal antenna and the second leg differ from one another in both the numbers and arrangement of axons. According to these criteria the nerve of the homeotic appendage was structurally identified as a leg nerve.Most of the antennal nerves studied showed a consistent grouping of axons in the profile. This suggests that the assemblage of the axons does not occur randomly, but in an ordered fashion.
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  • 161
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    Topics: Biology , Medicine
    Notes: The thymus glands of adult slimy salamanders (Plethodon glutinosus) were examined by light and electron microscopy with the objective of describing the populations of epithelial cells believed to be secretory. The results of various histochemical procedures designed to demonstrate nucleic acids, proteins, lipids, and mucosubstances were evaluated by light microscopy. Each thymus is incompletely subdivided into a variable number of interconnected lobules by trabeculae extending inward from a thin capsule composed of connective tissues. The thymic parenchyma lacks distinct cortical and medullary regions, although developing lymphocytes and plasma cells tend to accumulate in larger numbers in the outermost portions of the gland. Basophils are found regularly in the capsule and trabeculae, but only very rarely within the thymic parenchyma. The epithelial cells of the thymus can be classified into five categories: epithelial reticular cells; three varieties of granulated cells (types I, II, and III), and myoid cells. Epithelial reticular cells form a three-dimensional network which extends throughout all portions of the thymus. Type I and type II granulated cells can be distinguished from one another by various morphological criteria at the ultrastructural level, but only small differences in the composition of their inclusions can be demonstrated histochemically. Both types of granules are composed principally of a proteinaceous material containing an abundance of primary amino and guanidyl groups. In addition, most type I inclusions possess a lipid component that cannot be demonstrated in type II granules. Type III granulated cells possess very small cytoplasmic inclusions resembling those of gastroenteric endocrine cells. Myoid cells contain concentrically arranged myofibrils composed of sarcomeres. In favorably oriented material, small cysts can be identified whose walls are composed of mixtures of type I cells, type II cells, and epithelial reticular cells. Groups of degenerating epithelial cells form lamellated structures corresponding to Hassall's (thymic) corpuscles.
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  • 162
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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    Topics: Biology , Medicine
    Notes: A detailed morphometric study of the basilar membrane was made from serial sections and graphic reconstructions of the cochlea of three little brown bats. Four distinct morphometric changes were observed within the basilar membrane. First, between 0-1.4 mm from the basal end of the cochlea, there is a rapid increase in width and cross-sectional area of the basilar membrane. Secondly, between 1.4-2.5 mm, there is little change in width of the basilar membrane (its cross-sectional area is at its greatest in this region). Thirdly, between 2.7-3.1 mm, there is a sudden decrease in cross-sectional area concomitant with an increase in the width of the basilar membrane. Finally, between 3.1 mm and the apex, there is a gradual decrease in cross-sectional area concomitant with an increase in the width of the basilar membrane. The magnitudes of the cross-sectional areas of the scalae media and vestibuli decrease from base to apex, but this is not true for the scala tympani. The cross-sectional area of the scala tympani appears to decrease from the base to 0.7 mm, then it increases up to 1.4 mm, and then it decreases to the apex. These morphometric changes in the basilar membrane of the little brown bat are compared to those in other echolocating and non-echolocating mammals. The significance of these changes is discussed in relation to the range of hearing in the little brown bat.
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  • 163
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  • 164
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    Journal of Morphology 161 (1979), S. 157-167 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The mouthparts of female Corethrella brakeleyi and C. wirthi were studied using light and electron microscopy. Mandibles, hypopharynx and labium are highly sclerotized and are modified for obtaining blood meals. All structures were larger in C. brakeleyi than in C. wirthi except mandibular and hypopharyngeal teeth; these were smaller and more numerous in C. brakeleyi. The labium of both species terminates in peg-like structures which are similar to those reported from several genera of mosquitoes. Sensillae on the second segment of the maxillary palps appear to be identical to those described in both biting and nonbiting male and female blackflies.
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  • 165
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  • 166
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    Journal of Morphology 162 (1979), S. 275-309 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In order to provide an ontogenetic basis for the establishment of tetrapod muscle homologies and for the analysis of complex mammalian muscle states, a descriptive analysis of the morphogenesis of the thigh of Mus musculus has been made. The pattern and sequence of muscle cleavage and the migrations of individual muscle primordia are characterized from the eleventh day of gestation, when cleavage begins, through early neonatal stages. Observations on skeletal differentiation and lumbosacral plexus formation are also included. Thigh muscle morphogenesis is compared to that in the lizard, Lacerta, (Romer, '42) and the chick (Romer, '27) and homologies identified. An ontogenetic basis for the definition of ancestral and derived muscle states is provided in muscles that are morphologically variable in mammals. These include the gluteus minimus, gracilis, adductor brevis and several hamstring muscles. Certain muscles that show variable innervation patterns in adult mammals, i.e., pectineus, quadratus and adductor magnus, typically develop from premuscle regions that separate muscle anlagen innervated by different nerves. Two muscle anlagen appear in the embryonic mouse thigh and then disappear late in prenatal or early postnatal development. Comparisons with other mammals, especially the marsupial, Marmosa, reveal that these muscles are phylogenetic vestiges that degenerate before maturity. A sartorius vestige is identifiable through the thirteenth day of gestation. A tenuissimus anlage is present until shortly after birth and is clearly innervated by a branch of the peroneal nerve.
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  • 167
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    Notes: Differentiated Malpighian tubules of Periplaneta americana nymphs consist of four distinct regions. The distal, middle, and proximal regions are similar to the same regions in adult tubules. However, the transparent portion of the middle region was found to have ultrastructural characteristics different from those of the longer opaque segment of the middle region and the two other tubule regions. This newly distinguished region is called the lower middle region. Transitional zones, areas where cells show characteristics of two adjacent regions, are apparent between the distal and middle regions and between the middle and lower middle regions.The middle region of primary tubules undergoes an increase in autophagic activity and a modification of its basal infoldings and microvilli shortly before each molt. An increase in autophagic activity is also observed in the lower middle region near the time of molting.
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  • 168
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    Journal of Morphology 161 (1979), S. 169-175 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The vascular anatomy of five beavers (Castor canadensis) was studied by dissection and injection of arteries and veins with vinyl acetate. There is extensive countercurrent arrangement of arteries and veins distal to and including the common iliac artery and veins. Two types of countercurrent vessels occur (1) a venae comitantes type in which two or three veins surround a central artery, and (2) a modified rete type. The retia are located proximal to the large flat tail and the webbed hind feet. Two bypass veins are described for the feet and tail and the significance of these structures in temperature regulation is stressed.
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  • 169
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  • 170
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesen von DL-Serin Vorläufern (Glycolaldehyd und „maskierte“ Glycolaldehyde)Bei Behandlung von Vinylchloridepoxid (4) mit Wasser, von Chlorethylencarbonat (9) mit wäßrigen Basen, von Vinylacetat (1) oder Ethylvinylether (6) mit wäßrigem Kaliumchlorat und einer katalytischen Menge Osmiumtetroxid bildete sich Glycolaldehyd (5) (Schema 1). Der nicht isolierte Aldehyd 5 lieferte bei der Zelinsky-Stadnikoff-Aminosäure-Synthese DL-Serin mit 70% Ausbeute. Diese Methode ergab, direkt von den „maskierten“ Glycolaldehyden 2, 7, 9, 10, Vinylencarbonat (11), 13 oder 14 ausgehend, ebenfalls DL-Serin (Ausbeuten 35-70%), wogegen ausgehend von 4 kein Serin nachgewiesen werden konnte.
    Notes: On treatment of vinyl chloride epoxide (4) with water, of chloroethylene carbonate (9) with aqueous bases, of vinyl acetate (1) or ethyl vinyl ether (6) with aqueous potassium chlorate and catalytic amounts of osmium tetroxide, glycolaldehyde (5) was formed (scheme 1). The not isolated aldehyde 5, when submitted to the Zelinsky-Stadnikoff amino acid synthesis, afforded DL-serine in 70% yield. The latter method, when applied directly to the “masked” glycolaldehydes 2, 7, 9, 10, vinylene carbonate (11), 13 or 14, also gave DL-serine (yields 35-70%), whereas with 4 no serine formation could be detected (scheme 1).
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  • 171
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 175-195 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Rearrangement of the 9-Cyano-cis-bicyclo [6.1.0]nona-2,4,6-trien-9-yl Anion to the 9-Cyanobicyclo[4.2.1]nona-2,4,7-trien-9-yl Anion On the Problem of BicycloaromaticityReaction of methyl cis-bicyclo[6.1.0]nona-2,4,6-triene-9-anti-carboxylate (5b) with lithiumdiisopropylamide does not lead to deprotonation at C9 of 5b. Instead, a bridgehead cyclopropyl anion is formed which opens to give the allyl anion 12b.  -  In contrast, cis-bicyclo[6.1.0]nona-2,4,6-triene-9-anti-carbonitrile (5c) is also deprotonated at C9 leading to the 9-cyano-cis-bicyclo-[6.1.0]nona-2,4,6-trien-9-yl anion (1c), which rearranges comparatively fast (ΔG≠-43°C = 16.5 kcal · mol-1) to the 9-cyanobicyclo[4.2.1]nona-2,4,7-trien-9-yl anion (4c). Applying qualitative MO arguments of Goldstein and Hoffmann 4) one could explain the facile formation of the „bicyclo-aromatic“ 4c on the basis of ground state destabilization of 1c and stabilization of 4c. H/D-Exchange experiments, however, are at variance with this interpretation.  -  An additional stabilization of the transition state in the anionic sigmatropic rearrangement 1c → 4c as well as the opening the C1 — C9 bond instead of the central C1 — C8 bond are in agreement with HOMO-LUMO interactions.
    Notes: Die Umsetzung von cis-Bicyclo[6.I.0]nona-2,4,6-trien-9-anti-carbonsäure-methylester (5b) mit Lithiumdiisopropylamid führt nicht zu Deprotonierung an C9 von 5b. Statt dessen wird das Brückenkopfproton Hl abgespalten. Anionische Ringöffnung ergibt das Allyl-Anion 12b.  -  Im Gegensatz dazu wird das entsprechende 9-anti-Carbonitril 5c auch an C9 zum 9-Cyan-cis-bicyclo[6.1.0]nona-2,4,6-trien-9-yl-Anion (lc) deprotoniert, das vergleichsweise rasch (ΔG≠-43°C = 16.5 kcal · mo1) in das 9-Cyanbicyclo[4.2.1]nona-2,4,7-trien-9-yl-Anion (4c) umlagert. Qualitative MO-Überlegungen nach Goldstein und Hoffmann4) lassen vermuten, daß die leichte 1,5-Umlagerung auf Grundzustands-Destabilisierung von lc bzw. -Stabilisierung von 4c, mithin auf „Bicycloaromatizität“ von 4c, zurückzuführen ist. H/D-Austauschversuche zur Bestimmung von Anion-Stabilitäten stehen jedoch zu dieser Erklärung im Widerspruch.  -  Eine zusätzliche Stabilisierung des Übergangszustandes der anionischen sigmatropen Umlagerung 1c → 4c wie auch die seitliche statt der zentralen Bindungslösung im cyan-substituierten Anion 1c sind mit HOMO-LUMO-Wechselwirkungen zu verstehen.
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  • 172
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 260-265 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Thieno[3,4-cisothiazole]. Synthesis and Properties of a New Nonclassical Condensed ThiopheneThe triphenylthieno[3,4-c]isothiazole 3 is a new 10 π heteroarene containing two different masked 1,3-dipolar systems. Its synthesis from 4-phenyl-1,3.2-oxathiazolylium-5-olate (1) and dibenzoyl-acetylene via the direct precursor 2 as well as its photoelectronic and electronic spectra are desribed. The observed electronic transitions of 3 are compared with the results of a PPP-CI calculation
    Notes: Das Triphenylthieno[3,4-c]isothiazol 3 ist ein neuer 10 π-Heteroaromat, der zwei verschiedene maskierte 1,3-dipolare Systeme beinhaltet. Seine Synthese aus 4-Phenyl-1,3,2-oxathiazolylium-5-olat (1) und Dibenzoylacetylen über die direkte Vorstufe 2 sowie sein Photoelektronen- und Elektronenspektrum werden beschrieben. Die an 3 beobachteten Elektronenübergänge werden mit den Ergebnissen einer PPP-CI-Rechnung verglichen.
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  • 173
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 249-259 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transanular Interactions in [3.3]Phanes, III. [3.3]Paracyclophane, New Syntheses, Chair and Boat Conformation[3.3]Paracyclophane (1) was synthesized via the 2,13-dithia[4.4]paracyclophane (2) by vapor phase pyrolysis of the disulfone 3 obtained from 2. Reaction of 2 with benzyne gave trans- and cis-2,1 l-bis(phenylthio)[3.3]paracyclophane (4 and 5) by Stevens rearrangement. Oxidation to the sulfoxides 6 and 7 and pyrolysis yielded the [3.3]paracyclophanedienes (12/13) giving 1 on catalytic hydrogenation. Large substituents in the 2,11-positions of the bridges stabilize the two conformers of 1, based on 1H-NMR spectra the trans-isomer 4 has the chair, the cis-isomer 5 the boat conformation.
    Notes: [3.3]Paracyclophan (1) wurde über 2,13-Dithia[4.4]paracyclophan (2) durch Gasphasen-Pyrolyse des aus 2 erhaltenen Disulfons 3 synthetisiert. Reaktion von Dehydrobenzol mit 2 ergab durch Stevens-Umlagerung trans- und cis-2,11-Bis(phenylthio)[3.3]paracyclophan (4 und 5); durch Oxidation zu den Sulfoxiden 6 und 7 und Pyrolyse wurden die [3.3]Paracyclophandiene (12/13) erhalten, die bei katalytischer Hydrierung 1 ergaben. Große Substituenten in den 2,11-Positionen der Brücken stabilisieren die beiden Konformere von 1, laut 1H-NMR-Spektren liegt das trans-Isomere 4 in der Sessel-, das cis-Isomere 5 in der Wannen-Konformation vor.
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  • 174
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    Keywords: Chemistry ; Inorganic Chemistry
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Racemization of Spirocyclic Pentaaryl Derivatives of Group 5 A Elements. I H NMR Investigations with Overcrowded Asymmetric Phosphoranes, Arsoranes, and StiboranesThe two different methyl positions of bis-2,2′-biarylylenephosphorane 7, the corresponding arsoranes 8a, b, and the analogous stiborane 9 are reversibly equilibrated at elevated temperatures with free enthalpies of activation of 18.2 (76.0), 17.2 (72.2), ≈ 22.5 (94.2), and 15.4 (64.6) kcal(kJ)/mol. Starting with the trigonal bipyramidal ground state conformations C and ∪ (fig. 2) these ligand exchange phenomena can be interpreted in the framework of the pseudorotation process on the basis of trigonal bipyramidal transition states of type A with diequatorial biarylylene groups.
    Notes: Die beiden unterschiedlichen Methyl-Positionen des Bis-2,2′-biarylylenphosphorans 7, der entsprechenden Arsorane 8a, b und des analogen Stiborans 9 werden bei erhöhten Temperaturen mit freien Aktivierungsenthalpien von 18.2 (76.0), 17.2 (72.2). ≈ 22.5 (94.2) und 15.4 (64.6) kcal(kJ)/mol reversibel äquilibriert. Ausgehend von den trigonal-bipyramidalen Grundzustandskonformationen C und ∪ (Abb. 2) lassen sich diese Ligandenaustauschphänomene im Rahmen des Pseudorotationsprozesses auf der Basis trigonal-bipyramidaler Übergangszustände des Typs A (Abb. 2) mit diäquatorialen Biarylylen-Gruppen interpretieren.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 310-348 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Light-induced Reactions, XIII. On the Seco-isomeric Dienylketene Related to 2,4-Androstadien-1-oneThe steroidal 2.4-cyclohexadienone 3 photochemically affords the diastereomer 4. Both the configurational isomers differ exceedingly in their chiroptical properties. Their respective contribution to the photostationary state depends on the wave-length of the light and the solvent utilized. The dienylketene 5 can be determined spectroscopically as a transient. It is not trapped by 2,2,2-trifluoroethanol; cyclohexylamine, however, furnishes the 1,6-adduct 7a and/or the 1,2-adduct 6 a owing to the concentration and wave-length (365 or 313 nm) used.
    Notes: Das steroidale 2,4-Cyclohexadienon 3 geht photochemisch in das Diastereomere 4 über. Beide Konfigurationsisomere unterscheiden sich deutlich in ihren chiroptischen Eigenschaften. Ihr jeweiliger Anteil im photostationären Zustand hängt von der Wellenlänge des Lichts und dem Lösungsmittel ab. Das Dienylketen 5 läßt sich als Transient spektroskopisch nachweisen. Es wird von 2,2,2-Trifluorethanol nicht, von Cyclohexylamin je nach Konzentration und Wellenlänge (365 oder 313 nm) als 1,6-Addukt 7a und/oder als 1,2-Addukt 6a abgefangen.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 384-388 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclic Substances from N-Aryl-substituted PropiolamidinesThe chloroformamidines 4a-c react with lithium phenylacetylide to form the propiolamidines 5a-c. 5a and 5b cyclize upon treatment with polyphosphoric acid to give the 2-aminoquinolines 6 and 7,8, respectively; 5c yields only the spiro compound 9.
    Notes: Die Chlorformamidine 4a-c reagieren mit Lithium-phenylacetylid zu den Propiolamidinen 5a-c. 5a bzw. 5b cyclisieren in Polyphosphorsäure (PPS) zu den 2-Aminochinolinen 6 bzw. 7 und 8, während 5c als einziges Produkt die Spiroverbindung 9 ergibt.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 376-383 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structure of Melochinine, a New Type of a Pyridone Alkaloid from Melochia pyramidata L. (Sterculiaceae)Melochinine, isolated from leafs of Melochia pyramidata L., is the first representative of a so far unknown class of pyridone alkaloids. Its structure was determined by spectroscopic methods in combination with microchemical degradation reactions to be 3.
    Notes: Das aus Melochia pyramidata L. isolierte Melochinin gehört einer bisher unbekannten Klasse von Pyridon-Alkaloiden an. Seine Struktur 3 wurde mit spektroskopischen Methoden und mikrochemischen Abbaureaktionen bestimmt.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 392-393 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Photochemical Synthesis of (η5-C5H5)2V2(Co)5μ-Dicarbonyl-tricarbonylbis[(η5-cyclopentadienyl)vanadium](V-V) (2) has been synthesized in 89% yield by photolysis of tetracarbonyl(η5 -cylcopentadienyl)vanadium (1) in tetrahydrofuran using a falling-film photoreactor.
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  • 179
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    Berichte der deutschen chemischen Gesellschaft 112 (1979) 
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    Keywords: Chemistry ; Inorganic Chemistry
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  • 180
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 435-444 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Naturally Occurring Terpene Derivatives, 156. On a New Group of Sesquiterpene Lactones from the Genus TrixisTwo species of the South American genus Trixis afforded 12 new sesquiterpenes all with a new pentacyclic ring system, named trixikingolide (3-8 and 10-24). The structures are elucidated by spectroscopic methods and chemical transformations which are in part unusual. The carbon skeleton is that of an isocedrene (1), first found in several other genera of the tribe Mutisieae. This type is probably of chemotaxonomical importance.
    Notes: Zwei Vertreter der südamerikanischen Gattung Trixi ergeben 12 neue Sesquiterpene, alle mit dem neuen pentacyclischen Ringsystem. das wir Trixikingolid genannt haben (3-8 und 19-24). Die Konstitutionen werden durch spektroskopische Methoden und chemische Umwandlungen, die zum Teil ungewöhnlich sind, geklärt. Das Kohlenstoffgerüst ist das eines Isocedrens (1), das zuerst in mehreren Gattungen der Tribus Mutisieae gefunden wurde. Dieser Typ ist wahrscheinlich von chemotaxonomischer Bedeutung.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 468-479 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Azidocobalt(III) Chelate Complexes with IsocyanidesAzidochelatecobalt(III) complexes N3Co(chelate)B (la-e) [chelate = e. g. dianion of N,N′-o-phenylenebis(salicylidenimine), B = PPh3] react with organic isocyanides to give metal-carbon bonded tetrazolate complexes 3, 4. 2-Isocyanoethanol affords tetrazolato- (9, 10) or azido-oxazolidin-2-ylidene complexes (11), depending on the nature of the solvent, the trans-base B, and the chelate ligand. The mechanism of formation of C-coordinated tetrazoles from azido complexes and isonitriles is discussed.
    Notes: Azidochelatcobalt(III)-Verbindungen N3Co(chelat)B(la-e) [chelat = z. B. Dianion von N,N′-o-Phenylenbis(salicylidenimin), B = PPh3] setzen sich mit organischen Isocyaniden zu Tetrazolatokomplexen 3, 4 mit Cobalt-Kohlenstoff-Bindung um. Mit 2-Isocyanethanol entstehen in Abhängigkeit vom Lösungsmittel, der trans-ständigen Base B und dem Chelatliganden Tetrazolato-(9, 10) oder Azido-oxazolidin-2-yliden-Komplexe (11). Der Mechanismus der Bildung C-koordinierter Tetrazole aus Azidokomplexen und Isonitrilen wird diskutiert.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 532-540 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polycyclic Compounds, XII. Vicinal cis-trans-Isomeric Dihydrodiols in the Hexahydrophenanthrene and -benz[a]anthracene SeriesThe synthesis of the Vicinal trans-dihydrodiols 3a and 1la in the hexahydrophenanthrene and -benz[a]anthracene series is described. 3a and 1la are obtained by reaction of the oxanorbornadienes 1 and 9 with acetic acid and subsequent alkaline hydrolysis of the trans-hydroxyacetates 3b and 11b. Specific reactions of the cis-trans-isomers 2a and 3a are described.
    Notes: Die Darstellung der vicinalen trans-Dihydrodiole 3a und 11a in der Hexahydrophenanthren-und -benz[a]anthracen-Reihe wird beschrieben. 3a und 11a erhält man durch Reaktion der Oxanorbornadiene 1 und 9 mit Essigsäure und anschließende alkalische Verseifung der trans-Hydroxyacetate 3b und l1b. Spezifische Reaktionen der cis-trans-Isomeren 2a und 3a werden besprochen.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 818-822 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Reaction of L-Olivomycal and L-MycaralStarting with L-rhamnal (3) the synthesis of L-olivomycal (4a) is achieved with only few steps and in high yields. Following hydrogenation of 4a and the isomeric side product L-mycaral (5), to the corresponding 1,5-anhydro derivatives 7 and 8, only 8 gave a cis-carbonate 9. This proves the configuration at the branching point C-3 in 4a and in 5. By the reaction of 4b with methanol and N-iodosuccinimide 10b is obtained, which, after subsequent reduction employing nickel boride, gave methyl α-L-olivomycoside (11) in high yield. By application of the same procedure the disaccharide derivative 13 is synthesized without problems.
    Notes: Die Synthese von L-Olivomycal (4a) gelingt in wenigen Reaktionsschritten und guten Ausbeuten ausgehend von L-Rhamnal (3). Nach Hydrierung von 4a und dem isomeren Nebenprodukt L-Mycaral (5) zu den entsprechenden 1,5-Anhydroverbindungen 7 und 8 reagiert nur 8 zu einem cis-Carbonat 9, womit die Konfiguration am Verzweigungspunkt C-3 in 4a und 5 belegt wird. Umsetzung von 4b mit Methanol und N-Iodsuccnimid zu 10b und nachfolgende Reduktion mit Nickelborid gibt Methyl-α-L-olivomycosid (11) in hoher Ausbeute. Gleichermaßen gelingt die glatte Synthese des Disaccharidderivats 13.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 844-848 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal Structures of the Isopropoxides of Potassium, Rubidium, and CesiumPotassium-, rubidium- and cesium isopropoxide are isostructural (tetragonal space group P4/nmm-D4h7). Their cell constants have been determined. Using a single crystal the structure of cesium isopropoxide has been determined by X-ray analysis and refined to R = 0.069. The alkoxides form layer structures of the type of lithium respectively sodium methoxide. The metal atoms are arranged in one plane and are coordinated on both sides by O-atoms. each O-atom being surrounded by four metal atoms and one sec. C-atom. The methyl-C-atoms are distributed statistically between two positions differing by a 90° rotation of the (CH3)2CH-group.
    Notes: Die Isopropoxide des Kaliums, Rubidiums und Caesiums sind isostrukturell tetragonale Raum-gruppe P4/nmm-D4h7). Ihre Zellkonstanten wurden ermittelt und die Struktur des Caesium-isopropoxids anhand eines Einkristalls röntgenographisch bestimmt und bis R = 0.069 verfeinert. Die Alkoxide bilden Schichtgitter vom Typ des Lithium- bzw. Natriummethoxids. Dabei liegen die Metallatome in einer Ebene und sind beiderseits von O-Atomen koordiniert, indem jedes O-Atom von vier Metallatomen und einem sec. C-Atom umgeben ist. Die Methyl-C-Atome sind statistisch auf zwei Lagen verteilt, welche sich durch Drehung der (CH3)2CH-Gruppe um 90° unterscheiden.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1614-1625 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Electronic Structure of Alkyl Aryl and Alkyl Vinyl EthersFor the evaluation of the interactions between π electrons of the CC double bond and lone Pairs at the 0 atom of α, β-unsaturated ethers p. e. spectra of some alkyl aryl ethers 1-3 were recorded and compared with those of alkyl vinyl ethers 5. The data could be interpreted by means of orbital correlation diagrams provided the interaction with energetically high-lying σ orbitals of the correct symmetry was taken into account. Sterically hindered alkyl aryl ethers were found to exist in a perpendicular conformation; in sterically unhindered ethers like anisole a less stable isomer having this conformation was detected. In the case of alkyl vinyl ethers non-bonding interactions favour the s-cis conformation, whereas sterically hindered molecules of this type prefer the s-trans form. From p. e. spectra at higher temperatures (up to 510 K) the relative conformational energies are estimated. The results of the p. e. analysis are used for the interpretation of some reactions of α,β-unsaturated ethers.
    Notes: Um das Ausmaß der Konjugation zwischen π-Elektronen der CC-Doppelbindung und freien Elektronenpaaren am O-Atom α, β-ungesättigter Ether zu ermitteln, wurden die Photoelektronenspektren einer Anzahl von Alkyl-aryl-ethern 1-3 aufgenommen und mit den Spektren von Alkyl-vinyl-ethern 5 verglichen. Die Ergebnisse lassen sich mit Hilfe von Orbitalkorrelationsdiagrammen vollständing interpretieren, sofern man energetisch hochliegende σ-Orbitale geeigneter Symmetrie in die Betrachtung einbezieht. Sterisch gehinderte Alkyl-aryl-ether nehmen eine perpendikuläre Konformation ein, die bei sterisch nicht gehinderten Verbindungen wie etwa Anisol als zweite weniger stabile Form gefunden wird. Im Fall der Alkyl-vinyl-ether überwiegt aufgrund einer nichtbindenden Wechselwirkung die s-cis-Konformation bei sterisch nicht gehinderten Ethern, während sonst die s-trans-Konformation bevorzugt wird. Durch die Aufnahme von Photoelektronenspektren bei Temperaturen bis 510 k lassen sich die Energieunterschiede zwischen den verschiedenen Konformeren abschätzen. Die Ergebnisse der PE-Untersuchungen Können zur Interpretation von Reaktionen α,β-ungesättigter Ether herangezogen werden.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1635-1649 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Mechanism of the Photochemical Reactions of PhenylsydnonesThe light-induced decay of diphenylsydnone (1a in various solvents and in the presence of benzonitrile or 4-chlorobenzonitrile with evolution of carbon dioxide leads to the formation of a nitrile imine intermediate 4 a, whose products are partially isolated and identified. For example, the isomeric triazoles 5 (2.5%) and 7 (7.9%) beside the oxadiazolinone 6a (0.9%) and the phenylhydrazine 8 a (29 %) are formed during the irradiation 1a in acetone. The phenanthridinone derivative 22 and the N-phenylbenzohydrazide 24 are formed during working up of the irradiation mixture from 1a in pure acetyl chloride. Furthermore, the photolyses of 1b, c in acetone and of 1b or 6b in methanol are described. The formation of the isolated products is discussed.
    Notes: Der lichtinduzierte Zerfall des Diphenylsydnons (1a) in verschiedenen Lösungsmitteln sowie in Gegenwart von Benzonitril oder 4-Chlorbenzonitril liefert unter Kohlendioxid-Abspaltung eine Nitrilimin-Zwischenstufe 4 a, deren Folgeprodukte teilweise isoliert und identifiziert werden. Beispielsweise werden bei der Bestrahlung von 1a in Aceton die isomeren Triazole 5 (2.5%) und 7 (7.9%) neben dem Oxadiazolinon 6 a (0.9%) und dem Phenylhydrazin 8 a (29 %) gebildet. Das Phenanthridinon-Derivat 22 und das N-Phenylbenzohydrazid 24 entstehen bei der Aufarbeitung des Belichtungsansatzes aus 1a in reinem Acetylchlorid. Weiterhin werden die Photolysen von 1b, c in Aceton und von 1b oder 6 b in Methanol beschrieben. Die Bildungsweisen der isolierten Produkte werden diskutiert.
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  • 187
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1705-1711 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 3-O-Benzyl-D-ribose3-O-Benzyl-D-ribose (4) is synthesized from D-glucose and D-ribose via different routes; these methods were compared. For a characterization 4 is transformed into 3′-O-benzyl-adenosine (19). 1H NMR data of the synthesized compounds are compiled.
    Notes: Aus D-Glucose und aus D-Ribose wird in vergleichenden Untersuchungen auf verschiedenen Wegen 3-O-Benzyl-D-ribose (4) hergestellt. Zur Charakterisierung wird 4 in 3′-O-Benzyladenosin (19) übergeführt. 1H-NMR-Spektroskopische Daten der synthetisierten Verbindungen werden mitgeteilt.
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  • 188
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Complex Chemistry of Reactive Organic Compounds, XXIV. Five-Membered Cobalta Cycles from Carbene Addition to Dicarbonyl (η5-cyclopentadienyl)cobaltPhotolysis of the dialkyl diazomalonates 2a-g in the presence of dicarbonyl(η5-cyclopentadienyl)cobalt (1) in tetrahydrofuran yields the cobalta cycles 3a-g. The formation of the new compounds, established by X-ray structural determination on the case of 3c, can be explained formally as a result of a [2 + 3]-cycloaddition of the carbenes derived from the diazo precursors 2a-g to the organometallic substrate 1. The cyclic cobalt compounds 3a-g are converted by a thermal reaction with 1 through opening of the metalla cyclic structural element into the dinuclear μ-methylene cobalt compounds 4a-g.
    Notes: Durch Photolyse der Diazomalonsäure-dialkylester 2a-g in Gegenwart von Dicarbonyl-(η5-cyclopentadienyl)cobalt (1) in Tetrahydrofuran sind die Cobaltacyclen 3a-g zugänglich. Die Bildung der neuen, am Beispiel von 3c auch röntgenstrukturanalytisch gesicherten Verbindungen ist formal das Ergebnis einer [2 + 3]-Cycloaddition der von den Diazo-Vorstufen 2a-g abgeleiteten Carbene an das Organometall-Substrat 1. Unter Öffnung des metallacyclischen Strukturelements sind die cyclischen Cobalt-Derivate 3a-g bei thermischer Umsetzung mit 1 in die zweikernigen μ-Methylen-Cobalt-Komplexe 4a-g überführbar.
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  • 189
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1751-1755 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Planar Threefold Coordination of Sulfur(VI): Crystal and Molecular Structures of (R3SiN)3S and (R3CN)3S (R=CH3) at -130°CThe crystal structures of the title compounds were determined from single crystal X-ray data (measured at -130°C) and refined to unweighted R-values of 0.034 for (R3SiN)3S (1) and 0.047 for (R3CN)3S(2). 2 crystallizes in the triclinic space group P1 and 1 in the hexagonal space group P63/m. Both structures exhibit a planar threefold nitrogen coordination of the sulfur but the large coefficients of the temperature factors perpendicular to the SN3 planes in 1 and 2 might indicate a disorder due to small deviations from planarity. The S—N bond lengths were found to be 150.4 (1) and 151.5 pm (2, mean).
    Notes: Die Strukturen der Titelverbindungen wurden aus Diffraktometer-Einkristalldaten (gemessen bei -130°C) bestimmt und zu ungewichteten R-Werten von 0.034 für (R3SiN)3S )(1) und 0.047 für (R3CN)3S (2)verfeinert. 2 kristallisiert triklin, P1. Und 1 hexagonal, P63/m. In beiden Strukturen wird eine trigonal planare Koordination des zentralen Schwefelatoms beobachtet, doch deuten die relativ großen Koeffizienten der anisotropen Temperaturfaktoren senkrecht zu den SN3-Ebenen in 1 und 2 auf eine Fehlordnung als Folge geringer Abweichungen von der Planarität in den einzelnen Molekülen hin. Die S—N-Abstände betragen 150.4 pm (1) und 151.5 pm (2, Mittelwert).
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  • 190
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1743-1750 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Reactivity-Selectivity Principle, 4. Selectivity of Alkyl Radicals in Competition System BrCCl3/CCl4Alkyl radicals were generated from alkylmercuric salts 1 and peresters 4. Their reactions in competition system BrCCl3/CCl4 show that at 273 and 403 K the sequences of radical selectivities are completely reversed. At 273 K the methyl radical is the least selective but at 403 K it is the most selective alkyl radical of table 1. The isoselective temperature lies in the region of 340 K. The reason of this is the opposing influence on activation enthalpies and activation entropies. With increasing alkylation of the radicals, activation enthalpies enlarge but activation entropies reduce the selectivities (table 2). The differences of radical selectivities are governed below the isoselective temperature by variation of activation enthalpies and above the isoselective temperature by variation of activation entropies.
    Notes: Alkyl-Radikale wurden aus Alkylquecksilbersalzen 1 und Perestern 4 erzeugt. Ihre Reaktionen im BrCCl3/CCl4-Konkurrenzsystem zeigen, daß bei 273 und 403 K die Selektivitätsreihenfolge der Radikale einander genau entgegengesetzt ist. Während bei 273 K das Methyl-Radikal das am wenigsten selektive Radikal ist, besitzt es bei 403 K die größte Selektivität aller Alkyl-Radikale der Tab. 1. Die isoselektive Temperatur liegt im Bereich von 340 K Ursache für dieses Verhalten ist der gegenläufige Einfluß auf die Aktivierungsenthalpien und Aktivierungsentropien. Mit zunehmender Alkylierung der Radikale führen die Aktivierungsenthalpien. Zu einer Vergrößerung, die Aktivierungsentropien jedoch zu einer Verkleinerung der Radikalselektivitäten (s. Tab. 2). Unterhalb der isoselektiven Temperatur werden die Unterschiede der Radikalselektivitäten von den Änderungen der Aktivierungsenthalpien, oberhalb der isoselektiven Temperatur von den Änderungen der Aktivierungsentropien bestimmt.
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  • 191
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1756-1762 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Elimination of Olefins from Iminotriorganylphosphoranes in Liquid Ammonia SolutionIn the presence of potassium amide some iminotriorganylphosphoranes (1,2,5-7) react under elimination of olefins. The mechanism of this reaction is discussed.
    Notes: Bei Einwirkung von Kaliumamid in flüssigem Ammoniak spalten einige Iminotriorganylphosphorane (1,2,5-7) im Sinne einer Eliminierungsreaktion Olefin ab. Der Reaktionsmechanismus wird diskutiert.
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  • 192
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1763-1768 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions involving Hydrogen Transfer, III. Hydrogen-Transfer Between o,o′-Bridged Tetraarylethylenes and DiarylmethanesThermal hydrogen transfer between o,o′-bridged diarylmethanes and o,o′-bridged tetraarylethylenes leads to reduction of the ethylenes and to dimerization and dehydrogenation of the diarylmethanes (equ. (1)-(5)). The ethylene 1 reacts with 9,10-dihydroanthracene (15) to form 3 and anthracene (16)[equ. (6)]. The principles of these reaction are discussed.
    Notes: Bei der thermischen Wasserstoffübertragung zwischen o,o′-überbrückten Diarylmethanen und o,o′-überbrückten Tetraarylethylenen werden die eingesetzten Ethylene hydriert und die Diarylmethane dehydrierend dimerisiert (Gleichungen (1)-(5)). Das Ethylen 1 und 9, 10-Dihydroanthracen (15) liefern nach (6) 3 und Anthracen (16) Die Grundlagen dieser Reaktion werden diskutiert.
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  • 193
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1779-1784 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organometalphosphine-substituted Transition Metal Complexes, XXIV. Organoelement(IVb)-phosphine Derivatives of OctacarbonyldicobaltOctacarbonyldicobalt (1) reacts with (t-C4H9)3P (2), (t-C4H9)2PH (3), [(CH3)3Si]3P (4),[(CH3)3Ge]3P (5) [(CH3)3Sn]3P (6) and (t-C4H9)2[(CH3)3Si]P (7) with displacement of two CO ligands and formation of corresponding hexacarbonyldi(organoelement)IVb)-phosphine)-cobalt complexes. The vibrational and NMR spectra of the new compounds are discussed.
    Notes: Octacarbonyldicobalt (1) reagiert mit (t-C4H9)3P (2), (t-C4H9)2PH (3), [(CH3)3Si]3P (4), [(CH3)3 Ge]3P (5), [(CH3)3Sn]3P (6) und (t-C4H9)2[(CH3)3Si]P (7) unter Abspaltung von zwei CO-Liganden und Bildung entsprechender Hexacarbonyldi(organoelement(IVb)-phosphan)-cobalt-Komplexe. Die Schwingungs- und Kernresonanzspektren der neuen Verbindungen werden diskutiert.
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  • 194
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    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of Biologically Important Carbohydrates, 19. On the Regioselectivity of the vic. cis-Oxyamination of 3,4-Unsaturated Carbohydrates: Directed Syntheses of 4-Amino-4-deoxy- and of 3-Amino-3-deoxyaldosidesThe oxyamination of methyl 2-O-benzyl-3,4-dideoxy-α-D-glycero-pent-3-enopyranoside (1) with chloramine-T/[OsO4] yields a 2:1 mixture of methyl 2-O-benzyl-4-deoxy-4-tosylamino- (2) and of methyl 2-O-benzyl-3-deoxy-3-tosylamino-β-L-arabinoside (3). In the presence of a phase transfer catalyst the ratio is 4.5:1. In contrast benzyl 2-O-acetyl-3.4-dideoxy-α-D-glycero-pent-3-enopyrano-side (13) reacts with formation of the corresponding 4-deoxy-4-tosylamino- (14) and 3-deoxy-3-tosylamino-arabinoside 15 in the ratio 1:2. With reference to the preparative importance of this „reversal“ a hypothesis is given for the reasons of the observed regio orientation: in the reaction 1→2 + 3 through space interactions are supposed.
    Notes: Methyl-2-O-benzyl-3,4-didesoxy-α-D-glycero-pent-3-enopyranosid (1) reagiert mit (Chloramin-T/[OsO4 ] zu Methyl-2-O-benzyl-4-desoxy-4-tosylamino- (2) und Methyl-2-O-benzyl-3-desoxy-3-tosylamino-β-L-arabinosid (3) im Verhältnis 2:1. In Gegenwart eines Phasentransfer-Katalysators entstehen die isomeren im Verhältnis 4.5:1. Dagegen führt das Benzyl-2-O-acetyl-3,4-didesoxy-α-D-glycero-pent-3-cyanopyranosid (13) zum entsprechenden 4-Desoxy-4-tosylamino- (14) und 3-Desoxy-3-tosylamino-arabinosid 15 im Verhältnis 1:2. Auf die präparative Bedeutung dieser Umkehrung wird hingewiesen. Für ihre Ursachen wird eine Hypothese entwickelt: als Grund für die Regioorientierung bei 1→ 2 + 3 werden „through space“-Wechselwirkungen angenommen.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 3072-3080 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of i.(+)-Discadenine and its Deamino and Decarboxy DerivativesThe synthesis of L.(+)-discadenine (1) and its deamino (2a) and decarboxy derivatives (2b) is described. Alkylation of N6-N(,3-dimethylallylamino)purine with the bromo compound 4. ethyl 4-bromobutyrate or N-(3-bromopropyl)phthalimide, respectively, leads to the protected purine derivatives 5a-c. The position of alkylation was confirmed by 1H/1.3C NMR spectroscopy and pH dependent UV spectra and was shown to be N-3. The phthaloyl residues of 5a and c are removed by hydrazinolysis and the cleavage of the ester group in 5a and b is accomplished by alkaline hydrolysis. The reaction products 1, 2a and b are characterised by UV, 1H/C NMR, and mass spectra. The spectroscopic data are in full agreement with those of the spore germination inhibitor from Dictyostelium discoideum.
    Notes: Die Synthese von L(+)-Discadenin (1) sowie seinem Desamino- 2a und Descarboxy-Derivat (2 b) wird beschrieben. Alkylierung von N6-(3,3-Dimethylallylamino)purin mit der Bromverbindung 4 bzw. 4-Brombuttersäure-ethylester oder N-(3-Brompropyl)phthalimid führt zu den geschützten Purin-Derivaten 5a-c, deren Substitution an N-3 mit Hilfe der 1H- bzw. 13C-NMR-Spektroskopie und der pH-abhängigen UV-Spektren gesichert wurde. Hydrazinolyse entfernt die Phthaloylreste von 5a und c, alkalische Hydrolyse spaltet den Ethoxycarbonylrest in 5a und c. Die Reaktionsprodukte 1, 2a und b wurden durch UV, 1H/13C-NMR und Massenspektren charakterisiert. Die spektroskopischen Daten von L-Discadenin zeigten dabei volle Übereinstimmung mit denen des Sporenkeimungsinhibitors aus Diciyostelium discouicum.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 3110-3125 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A Reversible Rearrangement of the trans-Erythrinane Ring System, II. New trans-and 1(6→7)abeo-trans-ErythrinanesThe scope of the reversible rearrangement 1⇌2 is assessed. 1 and its monosubstituted derivatives 5-9 yield the trans-dihydroxy-1(6→7)abeo- trans-erythrinane lactams 10-23 (derivatives of “diol-A*”). Compounds such as 3/4 and 24/25 are, however, not formed under the same conditions. Under certain conditions, the reaction can be accomplished in two steps, in either direction. The rearrangement step consists of a spontaneous 1,2-shift of four reaction centres.
    Notes: Der Gültigkeitsbereich der umkehrbaren Gerüstumlagerung 1⇌2 wird abgegrenzt. Aus 1 und seinen monosubstituierten Derivate 5-9 erhält man die trans-Diol-1 (6 → 7)abeo- trans-erythrinanlactame (Diol-A*-Derivate)10 - 23, während Verbindungen vom Typus 3/4 und 24/25 unter den angewandten Bedingungen nicht darstellbar sind. Unter bestimmten Bedingungen können die Reaktionen in beiden Richtungen auch in zwei Schritten durchgeführt werden. Im Umlagerungsschritt wechseln jeweils vier Partner unter 1,2-Verschiebung spontan ihre Plätze.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 3166-3170 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Cyclopropenes, III. tert-Butylamino-Substitued Aromatic Compounds by Photocyclization of N-tert-Butyl(arylvinyl)ketene IminesN-tert-Butyl(arylvinyl)ketene imines 2a-g, obtained by ring-cleavage of the cyclopropenes 1a-g with tert-butyl isocyanide, cyclize on irradiation in a hexatriene-cyclohexadiene isomerisation with subsequent 1,7-hydrogen transfer to the tert-butylamino-substituted aromatic compounds 4a-f and 4g.
    Notes: Die durch Ringspaltung der Cyclopropene 1a-g mit tert-Butylisocyanid erhaltenen N-tert-Butyl-(arylvinyl)ketenimine 2a-g cyclisieren beim Bestrahlung in einer Hexatrien-Cyclohexadien-Isomerisierung mit anschließender 1,7-Wasserstoffverschiebung zu den tert-butylamino-substituierten Aromaten 4a-f und 4g.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 3203-3213 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Building Units for Oligosaccharides, XVII. Synthesis of Trehalosamine, Mannotrehalosamine, and Related α,α(1→1)-Linked Disaccharides6-O-Acetyl-2-azido-3,4-di-O-benzyl-2-deoxy-β-D-glucopyranosyl chloride (1) reacts with 2,3,4,6-tetra-O-benzyl-α-D-glucopyranose (2) in the presence of silver perchlorate and sym-collidine with good stereoselectivity to give the α,α(1→1)-linked disaccharide 3. Deblocking of 3 by sodium in liquid ammonia affords α,α-trehalosamine 5. Correspondingly, the reaction of 1 with the manno-derivative 6 affords 8, which can be converted into α,α-mannotrehalosamine 9. Several other α,α(1→1)-linked disaccharides of the trehalosamine type containing additional azido groups have been synthesized. The α,α(1→1)-linked disaccharides 21 and 23 containing 2-azido-2-deoxy-α-D-galactopyranose could be prepared, too.
    Notes: 6-O-Acetyl-2-azido-3,4-di-O-benzyl-2-desoxy-β-D-glucopyranosylchlorid (1) reagiert mit 2,3,4,6-Tetra-O-benzyl-α-D-glucopyranose (2) bei Gegenwart von AgCIO4 und sym-Collidin in guter Stereoselektivität zum α,α(1→1)-verknüpften Disaccharid 3. Entblockierung von 3 mit Natrium in flüssigem Ammoniak liefert Trehalosamin 5. Entsprechend führt die Umsetzung von 1 mit dem manno-Derivat 6 zu 8, aus dem das Mannotrehalosamin 9 freigesetzt werden kann. Eine Reihe weiterer α,α(1→1)-verknüpfter Disaccharide vom Trehalosamin-Typ, die zusätzliche Azido-Gruppen enthalten, wurden synthetisiert. Auch α,α(1→1)-verknüpfte Disaccharide 21 und 23 mit 2-Azido-2-desoxy-α-D-galactopyranose-Einheiten lieβen sich darstellen.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 3759-3765 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Addition Reactions of 2-Methoxyalkyl Radicals. A New Synthetic Method of Alkene TransformationThe (2-methoxyalkyl)mercury chlorides 5 und 8 react with NaBH(OCH3)3 in the presence of electron deficient alkenes 6a-1 to form the products 7a-1 and 9a-1. The yields of this C-C-formation reaction depend on the structure of the alkenes and the organomercuric salts (Table 1). A radical chain is proposed for the formation of 7 and 9 which is a formal addition of substituted alkanes to the alkenes 6.
    Notes: Die Umsetzung der (2-Methoxyalkyl)quecksilberchloride 5 und 8 mit NaBH(OCH3)3 in Gegenwart der elektronenarmen Alkene 6a-1 liefert die Addukte 7a-1 und 9a-1. Die Ausbeuten dieser C - C-Verknüpfungsreaktion hängen von der Konstitution der Alkene und der Organoquecksilbersalze ab (s. Tab. 1). Für die Bildung der Produkte 7 und 9, die formal eine Anlagerung von substituierten Kohlenwasserstoffen an die Alkene 6 ist, wird ein Radikalkettenmechanismus vorgeschlagen.
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    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 3907-3913 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Conjugation in Macrocyclic Systems, XXIX. Synthesis and Properties of Benzo [18]annuleneBenzo[18]annulene in which benzene and [18]annulene, as especially typical structures of benzenoid and non-benzenoid systems, are anellated was synthesized starting from 2 via 3, 4 (or 5), 6, and 7. Spectroscopic properties of 1 were studied under the aspect of the perturbation of the annulene conjugation by benzo-anellation. 1H NMR spectra show for 1 in comparison with 7, the immediate precursor without macrocyclic conjugation, a strong high-field shift for the internal protons and a down-field shift for the external protons, and thus prove the diatropicity of the [18]annulene system in 1.
    Notes: Benzo[18]annulen (1), in dem Benzol und [18] Annulen als besonders typische Strukturen benzoider und nicht-benzoider aromatischer Systeme anelliert sind, wurde ausgehend von 2 über 3,4 (oder 5), 6 und 7 synthetisiert. Spektroskopische Eigenschaften von 1 wurden unter dem Gesichtspunkt der Störung der Annulen-Konjugation durch die Benzo-Anellierung untersucht. 1H-NMR-Spektren zeigen für 1 im Vergleich zu 7. der direkten Vorstufe ohne makrocyclische Konjugation, eine starke Hochfeld-Verschiebung für die inneren Protonen und eine Tieffeld-Verschiebung für die äußeren Protonen; dies beweist die Diatropie des [18]Annulen-Systems in 1.
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