ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Cell & Developmental Biology  (125)
  • Life and Medical Sciences  (125)
  • 1980-1984
  • 1935-1939  (125)
  • 1938  (125)
Collection
Publisher
Years
  • 1980-1984
  • 1935-1939  (125)
Year
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 62 (1938), S. 3-15 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Comparisons have been made of the weights of the suprarenals of 525 mature female dogs in dioestrus, oestrus, pregnancy and lactation. Tables and graphs show that there was a slight increase in the size of the suprarenals during oestrus. There was hypertrophy of both the cortex and the medulla in the oestrous dogs. Only slight increase was shown in the weights of the glands of pregnant animals when the net body weight was considered and no increase when the total body weight was used in the study. There was no hypertrophy of the glands of lactating animals.There was only a slight variation in the seasonal occurrence of oestrus. From 34 to 37% of the total numbers of mature females examined in the seasons were found to be in oestrus. From 13 to 16% of the total numbers were found to be pregnant.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Nucleoli in the germ cells of certain Orthoptera, Hemiptera and the crayfish have been studied. In Ceuthophilus (camel cricket) these bodies are found to be definitely connected with chromatin threads and are believed to be products of chromatin.The large structure in the ova of Nemobius (cricket) is interpreted as a nucleolus because of its very irregular behavior and apparent complete disappearance.It is found that some of the nucleoli of Gelastocoris (toad bug) arise within the chromatin threads.Observations on Cambarus (crayfish) fail to show nucleolar extrusion, a phenomenon which has formerly been reported for this form.The unique behavior and fate of the nucleolar material in Pselliopus (true bug) is described. In this species the nucleolar material is added to and becomes part of the general oxychromatin network of the nucleus.This study fully supports the opinion that nucleoli have a chromatin origin.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A new limb skeleton will form in regenerating limbs of the larval Amblystoma in which the humerus had been completely removed. The cartilage of the new limb skeleton develops out of a blastema in which there are no cells of cartilage origin. This regeneration blastema is a composite structure made up of cells derived from a dedifferentiation of the injured tissues of the limb. The tissues which have been observed as contributing to the regeneration blastema are: muscles, especially the muscles of the shoulder; connective tissue of the sheath of the brachial nerve plexus; muscle connective tissue; and, to a certain extent, subcutaneous connective tissue. The new cartilage of the limb skeleton develops out of this composite blastema by means of a differentiation of cells in the central axis of the blastema.The amount of cartilage regenerated appears to depend on the mass of the blastema. When the blastema does not extend fully into the glenoid cavity of the scapula, the head of the developing humerus is deficient in size and structure. However, a complete limb skeleton is regenerated when the blastema does extend fully into the glenoid cavity.Since the new cartilage of the regenerated limb has no genetic continuity with the old limb skeleton, it would appear that the limb field exerts some kind of histogenetic determining action.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 62 (1938), S. 263-297 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Artemia salina, a very widely distributed species in North America, Europe and Asia, breeds freely and rapidly under laboratory conditions, living in all salinities from fresh water to almost saturated brine. Its soft exoskeleton permits of easy sectioning.The morphology and embryology of the segmentally arranged excretory glands - the antennal, mandibular and maxillary glands, are described. The antennal gland, consisting of extracellular end sac and intracellular excretory duct, is located in the second antenna and opens to the exterior on the lateroposterior face of the protopodite. It attains its maximum development by the sixth instar, degenerating by the tenth. The vestigial mandibular gland consists only of an end sac surrounding a schizocoele, and a rudimentary duct. The large maxillary gland in the adult consists of an end sac, an excretory duct of three circular coils, and a terminal duct opening to the exterior. The maxillary gland develops from a mass of mesenchyme cells in the maxillary segment of the nauplius, becoming fully differentiated by the sixth instar.The vestigial second maxilla has two bristles. It serves only as a terminus for the maxillary gland. A pair of small ganglia are accepted as internal evidence for the presence of a maxillular segment.The presence of three pair of schizocoeles in three consecutive segments is interpreted as evidence of homology with the Annelid coelome, with the possibility of further homologizing the excretory ducts with the segmental nephridia.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 62 (1938), S. 503-521 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In early embryonic stages of Passalus there are, in addition to the brain and suboesophageal ganglion, three thoracic and ten abdominal ganglia; one ganglion to each body segment. Before hatching the tenth, ninth and eighth abdominal ganglia coalesce. During the three larval instars the terminal ganglion remains in the sixth abdominal segment and only minor changes occur. By the end of the third day of pupal life the adult form of the nervous system is practically assumed. All abdominal ganglia are fused into a single, solid, elongated ganglionic mass. Connectives have disappeared between meso- and meta-thoracic and between metathoracic and abdominal ganglia; and with exception of the brain, sub-oesophageal and prothoracic ganglia, the entire ventral chain has come to lie in the mesothorax. The peripheral nerves still arise from the ganglia and ganglionic mass in their same relative positions and still supply the same segments in which they were originally located.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 62 (1938), S. 599-607 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Analysis of measurements of the trunk region of the vertebral column and of the various segments of the wing and leg skeleton in sixty-four specimens (thirty-four males, thirty females) of Fulica americana shows that: The males average about 7% larger (longer) than females in all parts of the skeleton; the difference is uniform throughout the body. The coefficient of variability ranges from about 3.00 (humerus, et al.) to about 5.00 (hind toe). The correlation between lengths of parts is very high between different segments of the wing skeleton, or of the leg; it is somewhat less between homologous segments of the wing and leg; and it is still less between limbs and trunk. This decreasing order of correlation indicates an increasing order of independence of variability. The wing proportions in Fulica are those characteristic of the type of flight called flatterflug. The proportions of the leg are those of a bird moderately adapted for cursorial locomotion; the very long toes characterize a swimming bird.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 62 (1938), S. 243-261 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Collections of Campeloma rufum were made at all seasons of the year from the Salt Fork River at Homer Park, Illinois, for gross anatomical and histological studies. No males nor male reproductive cells were found, all individuals showing definite female structures. The gonad, found on the columellar surface of the digestive gland, shows ovarian cells. A U-shaped tube from the albumen gland to the uterus receives the oviduct near its proximal end. This duct leads into a glandular pocket, the shell gland, which in turn empties into the sac-like uterus. The uterus terminates near the edge of the mantle in a muscular vaginal tube. The previously undescribed kidney, a glandular, pyramidal organ, lies posterior and to the left of the upper end of the mantle cavity. The kidney possesses two orifices opening into the pericardium and ureter respectively. The ureter opens between the vagina and the anus. Intra-uterine young were observed during all seasons of the year varying progressively from small veliger to fully formed young. A later paper on oogenesis, will attempt to substantiate parthenogentic reproduction for C. rufum.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A detailed study of Wright's polydactylous monster (produced by a semi-dominant lethal gene) indicates that it belongs to a general type found also in rare human cases. The diagnostic characteristics are: clubbed feet and approximately double the usual number of digits, embryonic posture, microphthalmia and enlargement of the diencephalon, and missing tibia and telescoped sternum; all organ systems in the body except the genital and circulatory are grossly abnormal. The defects appear to be produced by an arrest of morphogenesis and an alteration of relative growth rates. It is indicated that a controlling center of digit formation exists on the lateral (postaxial) side of the foot, that skeletal and dermal structures are controlled by it, but that muscles are differentiated according to the area of the limb in which they lie. The gene itself is not atavistic, although its effects in the heterozygote have that appearance.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Separation of the mantle from the visceral mass on the right side in deeply cupped species of oyster provides a shorter channel for egress of water from the right demibranchs. Correlated with this change is reduction in size of the right epibranchial chamber beneath the adductor together with backward displacement of the adductor itself. This water passage, designated the promyal chamber, develops during the first week after attachment of the oyster larva. The greatest displacement of the adductor and the largest promyal chamber occur in O. frons. The mantle border shows three reduplications of which the innermost, the pallial curtain, controls the amount and the place of entrance and egress of water. The importance of pallial curtains and promyal chamber to survival in turbid waters is discussed; oysters with the promyal chamber have invaded the river mouths, the flat oysters without this chamber have remained in the clear waters of high salinity near the sea. The bearing of these factors on the disappearance of fossil oysters is considered. It is proposed to relate to the genus Ostrea all flat, larviparous oysters which lack the promyal chamber and to raise the subgenus Gryphaea to generic rank to include all deeply cupped oviparous oysters with the promyal chamber. Anatomical and histological features of the pallium and branchial chambers are considered in detail.
    Additional Material: 21 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 62 (1938), S. 375-391 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A study is made of the pancreatic islands in Rana clamitans, R. catesbiana, R. sylvatica and Hyla versicolor during various stages of development. The islands, which were first seen in the 8-mm. R. clamitans larvae, originate from the endodermal cells of the primitive pancreatic anlagen. Following early larval development in all of the species, new islands differentiate from the cells of the pancreatic ductules. During metamorphosis, much of the acinous tissue degenerates, but the islands persist. They become aggregated and the definitive islands are formed from the primary islands before the mature adult stage is reached.With the azure-eosin technique, two types of island cells were distinguishable before, or at the time of metamorphosis, in all of the anurans studied. They are designated as the red and blue types. The blue cells are considered the primitive or embryonic type, and may transform into the red type; or the red type may originate independently.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...