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  • Artikel  (36)
  • Scanning electron microscopy  (16)
  • Triticum aestivum  (15)
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  • Springer  (36)
  • Cambridge University Press
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  • Springer  (36)
  • Cambridge University Press
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  • 1975-1979  (36)
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  • 1
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 9 (1976), S. 361-365 
    ISSN: 1432-1041
    Schlagwort(e): Propranolol ; atenolol ; hypertension ; cardio-selective ; beta-adrenergic blockade ; antihypertensive therapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary Propranolol was given to 30 patients with essential hypertension following randomised, double-blind administration of either placebo or a new cardioselective beta-adrenergic receptor antagonist, atenolol (Tenormin®, ICI 66 082). Both atenolol and propranolol caused statistically significant reduction of recumbent and erect blood pressure and heart rate. There were no important differences between these variables on comparison of atenolol and propranolol.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 9 (1976), S. 355-360 
    ISSN: 1432-1041
    Schlagwort(e): Propranolol ; minoxidil ; hypertension ; cardiac output ; plasma renin activity ; non-invasive techniques
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary A study, using non-invasive techniques, was carried out in ten patients with essential hypertension to examine the mechanism of the hypotensive effect of propranolol when used in combination with a potent vasodilator antihypertensive — minoxidil. The hypotensive effect of minoxidil, a mean (± SEM) decrease of 42.4±4.3 mm Hg, was accompanied by a marked increase in heart rate, cardiac index and plasma renin activity and a significant decrease in total peripheral resistance, limb vascular resistance and pre-ejection period. Addition of propranolol further reduced mean arterial pressure by an average of 12.9±2.0 mm Hg. Propranolol returned cardiac index to control values and total peripheral resistance index rose but not to control levels. Plasma renin activity was significantly reduced by propranolol. By multiple regression analysis no correlation was found between propranolol-induced decrease in mean arterial pressure and changes in cardiac index, total peripheral resistance index or plasma renin activity. Quantitatively, the reduction in cardiac index observed probably accounted for the hypotensive effect of propranolol. The role of plasma renin activity reduction in the hypotensive effect of propranolol in this situation remains to be clarified. The findings in the present study were consonant with the known actions of vasodilator antihypertensive agents and propranolol and indicate the applicability of non-invasive methodology to the investigation of cardiovascular drugs in man.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    European journal of clinical pharmacology 10 (1976), S. 177-182 
    ISSN: 1432-1041
    Schlagwort(e): Hydrochlorothiazide ; hypertension ; serum potassium ; total body potassium ; serum uric acid ; fasting blood sugar
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Summary The antihypertensive activity and side effects of three doses of hydrochlorothiazide combined with a potassium supplement (Esidrex®-K novum, Ciba) were determined in 40 hypertensive subjects in a double-blind, cross-over study. The lowest daily dose (12.5 mg) gave almost the same blood pressure reduction as the doses in common use (25 mg and 50 mg) and as the adrenergic beta-blocking agents previously employed. Metabolic side effects in the form of decreased serum potassium and increased fasting blood sugar and serum uric acid were observed in patients on the lower dose and, with the exception of serum uric acid, were only slightly more pronounced with the higher doses. The frequency of subjective side effects, on the other hand, increased with increasing dose. No changes were noted in total body potassium at any dose level. It is suggested that hydrochlorothiazide in low dose, alone or in combination with other antihypertensive agents, is a useful therapeutic regimen in mild hypertension.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Archives of microbiology 109 (1976), S. 9-14 
    ISSN: 1432-072X
    Schlagwort(e): Candida utilis ; Saccharomyces cerevisiae ; Colloidal gold ; Cytochemistry ; Mannan ; Plasma membranes ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The β(1→3)glucanase of Basidiomycete QM 806 was used to prepare Saccharomyces cerevisiae and Candida utilis protoplasts. Plasma membranes isolated from S. cerevisiae contained a small amount of mannose and traces of glucose and ribose. Randomly distributed α-mannan was detected by scanning electron microscopy at the surface of prefixed protoplasts using colloidal gold labelled with Concanavalin A as a marker. C. utilis protoplasts were also marked with anti-mannan antibodies. Again the distribution of mannan was random. This experiment indicated also that plasma membrane mannan has the same immunochemical determinants as cell wall mannan. It is hypothesized that mannan is mainly located in the outer layer of plasma membranes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Archives of microbiology 109 (1976), S. 31-35 
    ISSN: 1432-072X
    Schlagwort(e): Scanning electron microscopy ; Chlamydomonas ; Cell agglutination ; Cell fusion ; Flagella
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A technique has been developed by which mating gametes of Chlamydomonas eugametos can be studied in the Scanning Electron Microscope. A detailed description of the mating process, from the initial flagellar agglutination until the release of free vis-à-vis pairs, is presented. Flagella appear to agglutinate at random points on their surface. This is followed by a rapid increase of the contact area such that they “line-up” tip to tip. Flagella always exhibit a typical position prior to cell fusion. After cell fusion the flagella of a pair separate rapidly while the female have shortened about 33%. In a vis-à-vis pair the plasma bridge has contracted. The observations are interpreted in terms of a specific reorganization of the sexuale aggregate.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 6
    ISSN: 1573-4927
    Schlagwort(e): chromosome substitution ; nitrate reductase ; nitrite reductase ; acid proteinase ; Triticum aestivum
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The levels of nitrate reductase, nitrite reductase, and acid proteinase were compared in the primary leaves of 8-day-old wheat seedlings of Chinese Spring, Hope, and the 21 disomic substitution lines of Hope in Chinese Spring. Two chromosomes, 7B and 7D, were considered to contain genes controlling the level of nitrate reductase. Substitution of Hope chromosome 7B caused a highly significant increase in the in vitro stability of nitrate reductase. Nitrite reductase appeared to be controlled by two major genes, located on chromosomes 4D and 7D, and two minor genes, located on chromosomes 3D and 5A. In the case of acid proteinase, substitution of chromosome 1D caused a significant reduction in enzyme activity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 170 (1976), S. 145-159 
    ISSN: 1432-0878
    Schlagwort(e): Neurogenesis ; Retina ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Fixed retinae of chick embryos and chicks of the first week after hatching were fractured and examined with the scanning electron microscope. The matrix cells of the retina proliferate up to the beginning of the second week. The migrating cells are oriented in cell cords. This columnar organization prevails up to the development of the plexiform layers formed as a consequence of the outgrowth of the dendritic and axonal cell processes. Special attention was paid to the differentiation of the ganglion, bipolar and receptor cells, and the radial fibers (Müller cells). Two main morphological patterns are significant for the organization of the retina during neurogenesis: a) the cell to cell contacts of migrating cells and b) the spatial arrangement of Müller cells which could provide guidelines for migration of neuronal elements.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 174 (1976), S. 129-137 
    ISSN: 1432-0878
    Schlagwort(e): Pineal organ, human ; Acervuli ; Scanning electron microscopy ; Transmission electron microscopy ; Electron probe microanalysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Untreated, decalcified and trypsinized acervuli from human pineal bodies were studied with the scanning and transmission electron microscope as well as by electron probe microanalysis. The mulberry-like acervuli are composed of a various number of spherical lobes (135–800 μm) between which clustered groups of globuli (4–14 urn in diameter) are observed. The acervular lobes are very probably formed by an aggregation of these globuli. Small round particles 125–500 Å in diameter are observed on the surface of the pineal concretions. These are not influenced by either decalcification or trypsin treatment. The acervular mineral corresponds morphologically to hydroxyapatite. The electron probe microanalysis reveals the existence of calcium and phosphorus as main components of the acervuli. Small quantities of magnesium and strontium were also detected.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 170 (1976), S. 1-16 
    ISSN: 1432-0878
    Schlagwort(e): Tissue culture cells ; Mycoplasma ; Light microscopy ; Transmission electron microscopy ; Scanning electron microscopy ; Morphometry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The host-parasite relationship of HeLa M cells artificially infected with a bovine species of Mycoplasma was studied by light microscopy, transmission electron microscopy and scanning electron microscopy. The use of morphometry to quantitate some of the findings was explored. The parasites were seen in locations extracellular to the cell surface. The detection of small numbers of organisms by light microscopy was well demonstrated by use of the fluorescent antibody technique. Scanning electron microscopy proved to be an excellent method for revealing the surface details of cell-parasite morphology. Ultra-thin sections showed that the parasites are aligned mostly parallel to the plasma membrane of the host cell but separated by a gap of 10 nm. Morphometry indicated an average of 69 organisms per cell surface occupying 1.7% of the surface area. An increase of 26% in diameter of the HeLa cells, possibly as a result of infection, was observed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 10
    ISSN: 1432-0878
    Schlagwort(e): Axons ; Scanning electron microscopy ; Neurones, afferent ; Nerve regeneration ; Spinal nerve roots
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Rat dorsal spinal nerve roots were cut and the tip on the ganglionic side of the cut was examined by scanning electron microscopy at 0, 7, 20 and 48 h after operation. Seven hours after cutting, free axonal sprouts had started to protrude from the cut end of the nerve. After 20 h the free sprouts were more profuse than at 7 h but were smaller and had a rougher surface. At both 7 and 20 h many of the sprouts consisted of a stalk 2–7 μm in diameter with a bulbous end 5–20 μm in diameter. A few branching sprouts were seen. At 48 h the sprouts were shrunken with a deeply furrowed surface. The significance of the surface structure of the sprouts is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 11
    ISSN: 1432-0878
    Schlagwort(e): Epididymal epithelium ; Castration ; Androgen-substitution ; Japanese monkey ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The caput epididymidis from castrated and androgen-supplemented, castrated Japanese monkeys was observed with the scanning electron microscope. The experimental findings were compared with the normal structures in control animals. The epididymal lumen of control animals was lined by a tall, pseudostratified columnar epithelium possessing long, slender stereocilia which were densely arranged in a tuft-like form. After castration, the epididymal epithelium was decreased in height to one-fifth of controls. The stereocilia were also considerably reduced in length and in number, resulting in a flattened epithelial surface with polygonal boundaries. Frequent projection of a long, single cilium from an epithelial cell into the lumen was also a prominent feature in the epididymal ducts of the castrated animals. Administration of testosterone to the castrated animals resulted in almost complete recovery of the epididymal epithelium as well as regeneration of the stereocilia which regained a tuft-like arrangement.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 12
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 172 (1976), S. 379-388 
    ISSN: 1432-0878
    Schlagwort(e): Chitons ; Receptors ; Shell surface ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The shells of the chitons Lepidochitona cinereus, Sypharochiton pelliserpentis, Amaurochiton glaucus and Onithochiton neglectus were examined by scanning electron microscopy. In all species the surface terminations of the megalaesthete and micraesthete organs could be identified lying flush with the shell surface, as well as, lenses of the shell eyes in O. neglectus. Periostracal debris and encrusting diatoms were a usual feature of the shell surfaces. The micraesthete subsidiary caps normally appear featureless, but the megalaesthete apical caps sometimes appear to be perforated. The reasons for this perforate appearance are discussed and it is concluded that it provides no evidence for the normal passage of substances out of or into the megalaesthete.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 13
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 166 (1976), S. 65-70 
    ISSN: 1432-0878
    Schlagwort(e): Collagen ; Bone ; Cell culture ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Embryonic and young rat bone cells have been grown in culture and examined in the scanning electron microscope (SEM). Compared with cells fixed in situ and taken directly from the animal, the cultured osteoblastic cells were smoother, flatter and more extensive and showed tighter intercellular contacts. Some matrix is formed in culture and undergoes at least partial mineralization as judged by the accumulation of Ca and P measured by energy dispersive x-ray analysis. Findings concerning the morphology of the collagen arrangement were indecisive. Some superficial cells, free of surrounding matrix, resembled osteocytes in normal in vivo bone. This may indicate that a proportion of the extracellular matrix produced by the cultured cells failed to polymerise into recognizable bone matrix, and that osteocytic morphology is not dependent upon the physical characteristics of the bone matrix.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 14
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 169 (1976), S. 277-287 
    ISSN: 1432-0878
    Schlagwort(e): Rabbit gametes ; Cryofractography ; Scanning electron microscopy ; Transmission electron microscopy ; Zona pellucida
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Rabbit ova fertilized in vitro were prepared for scanning electron microscopy by ethanol-cryofracturing and critical-point drying methods and were also embedded and sectioned for transmission electron microscopy. Study of a region of interaction between sperm and zona pellucida with scanning electron microscopy reveals the latter to be composed of a complex network of fibers interspersed with numerous pores. Transmission electron microscopy of the same region reveals a “typical” homogeneous composition of the zona pellucida. Ultrastructural observations of thin sections passing through the region of sperm-egg interactions or through other regions of the ovum or its investments reveals very little methodological distortion of the various intracellular organelles or matrix. Application of the procedures described provides not only an elucidation of surface detail but also reveals intracellular cytoplasmic information about the same specimen during in vitro fertilization.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 15
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 169 (1976), S. 449-465 
    ISSN: 1432-0878
    Schlagwort(e): Bone ; Osteoblasts ; Cell surface ; Cell shape ; Calcitonin ; Parathyroid extract ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Neonate rat endocranial osteoblasts were cultured on their bone surfaces in control medium (CC) or medium to which either parathyroid extract (PTE) or calcitonin (CT) had been added for 2, 4, 8 or 24 h. Some were cultured for 24 h in CC, then for 2, 4, 8 or 24 h in either CT or PTE medium; or for 24 h in PTE, then for 2, 4, 8 or 24 h in either CC or CT; or 24 h in CT and 2, 4, 8 or 24 h in CC. The dorsal ruffling of the cells in CC was found to be suppressed by later culturing with PTE and the disoriented cells reorganized to form arrays of parallel cells. The effects of PTE were also reversed by CC or CT: the osteoblasts in the second culture (CC) lost elongation and order, and proceeded through a proliferative phase before exhibiting the ruffling form similar to a single CC 24 h culture. PTE-cultured osteoblasts showed an increase in cell overlap and contact so that a more competent barrier was formed separating the bone from the medium. In control or CT medium, however, intercellular gaps were greater than in vivo.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 16
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 166 (1976), S. 91-100 
    ISSN: 1432-0878
    Schlagwort(e): Kidney (rat) ; Uriniferous tubule ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The fine structure of luminal surface of clearly identified portions of uriniferous tubules has been studied by scanning electron microscopy to elucidate some controversies concerning the topography of certain surface formations. The results show a characteristic pattern of the luminal surface in the region of Henle's loop, which was assumed by previous authors, to belong to the collecting tubule. Furthermore it is demonstrated that no cilia are present within the terminal portion of the collecting tubules.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 17
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 174 (1976), S. 499-518 
    ISSN: 1432-0878
    Schlagwort(e): Fibroblast ; Human ; Transmission electron microscopy ; Scanning electron microscopy ; Aggregation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The different stages during aggregation of diploid human skin fibroblasts have been examined by transmission and scanning electron microscopy. As a result of aggregation, fibroblasts form a complex tissue configuration. Numerous intercellular junctions can be observed, while the cells remain polygonal and do not develop an organised intracellular cytoskeleton. Cell division occurs only rarely. After aggregation, signs of progressive auto-digestion develop. Adhesion to a substrate results in outgrowth of the cells and monolayer formation, even when extensive cell damage had occurred. The morphology of fibroblasts in aggregates and in the monolayers, from which they were derived, is compared and the contribution of the aggregate system to the study of fibroblast behavior is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 18
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 166 (1976), S. 299-314 
    ISSN: 1432-0878
    Schlagwort(e): Renal glomerulus (Rat) ; Endothelial cells ; Blood capillaries ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The rat kidney was perfused with saline and glutaraldehyde, treated with Murakami's tannin-osmium impregnation method, ethanol-freeze cracked and dried by the critical point method. Gold-palladium evaporated specimens were observed in a field-emission scanning electron microscope. The glomerular filtration membrane, fractured in different planes was observed with the following results: 1. Adjacent pedicles originate from different podocytes. No interpedicular bridges of apparent cytoplasmic nature could be found. 2. The basement membrane, in grazing fractures shows a horizontally layered architecture. 3. The attenuated endothelial sheet (lamina fenestrata) is divided into compartments, which we suggest should be called “areolae fenestratae”, by cytoplasmic crests radiating from the nucleated portion of the endothelial cell. A crest also occurs along the cell margin, which contacts a similar crest at the margin of the adjacent cell. 4. The pores in the areolae fenestratae are variable in size (30−150 nm diameter). A knob-like projection from the apparently naked basement membrane is found in a portion of the pores. 5. Numerous microvilli may occur on the endothelium. Some of them anastomose and fuse with one another to form a net whose meshes appear identical with the endothelial pores. Domes and shelves formed of a fenestrated cytoplasmic sheet also occur above the ordinary level of the endothelial lining. A hypothesis implicating microvilli in partial renewal of the endothelial sheet is proposed. This study was assisted by Mr. K. Adachi of the SEM Laboratory at the Niigata University School of Medicine.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 19
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 167 (1976), S. 425-438 
    ISSN: 1432-0878
    Schlagwort(e): Scanning electron microscopy ; Crystalline lens ; Microphthalmos
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The surface features of cortical fibers from lenses of normal adult rats and microphthalmic rats of the Browman strain have been studied by scanning electron microscopy. In the normal lenses, superficial cortical fibers follow a straight course from inner to outer pole whereas the deeper cortical fibers, while straight near the poles, pursue an undulating or zig-zag course at and near the equator. Almost all of the fibers are hexagonal in cross section and all fibers throughout their entire length are bound by interdigitating processes at each corner of the hexagon to corners of two adjacent fibers. Some fibers are also affixed by a single row of ball and socket junctions located on their broad outer and inner surfaces. Lens fibers from Browman rats display both minor and major abnormalities. These included segmentation, formation of incisures and lateral protrusions, corrugation and villous-like alteration of the broad fiber surface and development of parallel ridges on broad surfaces in a basket-weave pattern.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 20
    ISSN: 1432-0878
    Schlagwort(e): Retina ; Haplochromis burtoni ; Photoreceptor cells ; Light-adaption, dark-adaption ; Scanning electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The photoreceptor layer in the retina of Haplochromis burtoni (Cichlidae, Teleostei) was studied by scanning electron microscopy. Three types of receptors were identified: rods, single-cones and double-cones. The three-dimensional arrangement of these photoreceptors is described in the light- and dark-adapted retina. The surface of the inner segment of the photoreceptor cells displays fine vertical fissures which give rise to slender processes. These so called calycal processes which are of different lengths in rods and cones, surround the beginning of the smooth-surfaced outer segment. The myoid, the contractile part of the receptor, which is located beneath the ellipsoid, was examined in the single-cones of the dark-adapted retina. It is a slender structure with surface infoldings. The myoid, studied by transmission electron microscopy, contains bundles of parallel myofilaments, which are thought to be contractile.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 21
    Digitale Medien
    Digitale Medien
    Springer
    Bulletin of experimental biology and medicine 81 (1976), S. 938-940 
    ISSN: 1573-8221
    Schlagwort(e): interstitial cells of the kidney ; lipid granules ; hypertension ; electron-microscopic morphometry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract The content of lipid granules in the interstitial cells (IC) of the renal medulla of rats with genetic spontaneous hypertension (rats of the SHR strain) was studied by electron-microscopic morphometry. At the age of 1.5 months no difference was found in the volume of the lipid granules in SHR and Wistar (control) rats. At the age of 1 year the total volume of lipid granules in hypertensive SHR rats exceeded their volume in the control. At the same time, features of hypertrophy and hyperplasia of the rough and smooth endoplasmic reticulum and Golgi complex were found in the SHR rats, especially in the period of formation of hypertension. It is evidently not the degree of reduction in the volume of lipid granules, as was hitherto considered, but the state of the organelles of synthesis and secretion that must be used as the morphological criterion of IC function in arterial hypertension.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 22
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 387-391 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; Hordeum vulgare ; barley ; screening nursery ; distance between control plots ; protein content ; correlation coefficient
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Correlation coefficients were calculated in two seasons, between protein content of control plots of ‘Kyperounda’ durum wheat and ‘Athenais’ barley sown at distances of from 0.6 m to 68.4 m. Simple correlation coefficients were high (0.737, 0.710 and 0.311) and significant at the 1% level of probability for plots 0.6 m apart, but decreased rapidly with increasing distances between plots. The correlation in four nurseries was significant for plots 7.2 m, 4.2m, 4.2 m and 1.8 m apart. It was concluded that a control plot provides a fairly good measure of the protein content of adjacent plots.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 23
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 375-386 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; gametocide ; pollen stainability ; male sterility ; female sterility ; hybrid seed ; hybrid wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The gametocidal effects of RH-531, RH-532, and RH-2956 were studied with three rates and times of foliar application on two spring wheat (Triticum aestivum L.) varieties, Anza and Yecora 70. RH-531 and RH-532 applied at or before booting stage caused rather large reduction in plant height while RH-2956 had a small effect on height. Application of any of the three chemicals on ‘Anza’ at meiotic stages reduced self-pollination (SP) fertility by 97–99%. If 90% SP fertility reduction is acceptable, the application time could vary from premeiosis to postmeiosis for ‘Anza’. ‘Yecora 70’ was less sensitive than ‘Anza’ to gametocide treatments. The lowest SP fertility obtained in ‘Yecora 70’ with RH-531, RH-532, and RH-2956 was by treatment at booting (4 kg/ha), at premeiosis (2 kg/ha), and heading (8 kg/ha), and the corresponding SP fertility reductions were 74, 89, and 71%. Pollen stainability-determined by aceto-carmine, IKI, and Alexander's stains-was not affected by gametocide treatment and was not useful in evaluating sterility induced by these chemicals. For the RH-531-treated ‘Anza’ and ‘Yecora 70’ and the RH-532-treated ‘Anza’, more than 94% of the seeds produced by open-pollination on treated plants were from self-or sib-pollination as determined by progeny testing. However, RH-532-treated ‘Yecora 70’ and RH-2956-treated ‘Anza’ and ‘Yecora 70’ did result in more crossed seeds, with a maximum of 20% outcrossing. It was believed that spike compactness induced by the chemicals and the related poor flower opening were the major limitations for outcrossing. Artificial pollinations made to the test varieties showed that RH-531 induced both male and female sterility and was undesirable for practical use. RH-532, however, could be applied at the booting stage to avoid severe female sterility, and RH-2956 clearly was the best of the three chemicals, with the female fertility very close to those of the untreated checks of both ‘Anza’ and ‘Yecora 70’. Of the three chemicals, RH-2956 gave the highest percentage of hybrid plants in the progeny of hand-or open-pollinated spikes. Its practical use for hybrid seed production, however, will depend largely on improvement of methods to increase cross pollination in wheat.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 24
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 457-461 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; leaf angle ; erect leaves ; diallel ; additive gene effects
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary A 6×6 diallel was prepared to study the inheritance of leaf angle in T. aestivum L. Genetic analysis in terms of diallel cross parameters and graphic analysis indicated the control of additive gene effects in the expression of this character. The results of F1 analysis were supported by the analysis of F2 data.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 25
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 471-483 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat hybrid weekness ; hybrid grass-clump dwarfness ; hybrid dwarfness ; physiology ; genetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The growth of all grass-clump dwarfs is sensitive to temperature with low temperature giving rise to the grass-clump phenotype and high temperature producing normal phenotype. A continuous temperature of 26°C is required for normal growth of Type 1 dwarfs, a continuous temperature of 21°C is required for normal growth of Ty[e 2 dwarfs and a continuous temperature of 16°C is required for normal growth of Type 3 dwarfs. Genetic studies show that the inheritance of the grass-clump characteristic is due to three complementary dominant genes. The grass-clump growth habit is produced as a result of the temperature sensitivity of the apical meristem. In grass-clump plants low temperature treatment results in the cessation of cell division, DNA synthesis and phospholipid synthesis in the apical meristem. The primary temperature lesion has not been identified. Prolonged low temperature treatment of grass-clump plants results in extensive cell necrosis in a region just below the apical meristem; this cell death results in the permanent inactivation of the apical meristem.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 26
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 489-498 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; photoperiodic sensitivity ; maturity ; genetics ; adaptation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Photoperiodic respose, as assessed by a regression technique, exhibited complete dominance averaged over the crosses of an eight parent diallel in the vernalized condition. Photoperiodic response as final leaf number for the vernalized 8-hour photoperiod diallel was closely related to photoeriodic response of the regression method. However, the diallel analyses of both sets of data showed little agreement in terms of respectieve array positions. The inheritance of photoperiodic response in diallels using regression values showed little agreement between the vernalized and unvernalized conditions. This difference was postulated to be due to interaction of vernalization and photoperiodic response in the unvernalized situation. In the unvernalized condition photoperiodic response exhibited non-allelic interaction, attributable mainly to the cultivar Pinnacle in general behaviour in its crosses. Its removal gave a situation of high average dominance for photoperiodic response with a clear indication that high photoperiodic sensitivity was dominant to comparative insensitivity. Days to ear emergence (vernalized and 18-hour photoperiod) exhibited non-allelic interaction in its expression, due mainly to the general behaviour of the cultivar Pinnacle in its crosses. Removal of its array gave a situation of a moderately strong degree of overdominance in the expression of days to ear emergence. Maturity differences amongst parents and F1's, vernalized and under 18-hour photoperiod, are postulated to be due to a factor other than vernalization or photoperiodic response beheved to be growth temperature in differentially in fluencing growth and/or developmental rates between genotypes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 27
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 565-576 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; chromosome substitution lines ; kernel hardness ; baking absorption ; dough stability ; baking quality ; genetic analysis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary An attempt was made to identify the chromosomal location of genetic control of a few components of wheat quality, using chromosome substitution lines of Cappelle Desprez, Cheyenne, Hope, and Timstein into the recipient variety Chinese Spring. Major factors for kernel hardness and increased baking absorption were found on chromosomes 5D of Cheyenne and Hope, and on 3B, 5D and 7D of Timstein. In Timstein, the presence of one of these chromosomes sufficed to make the wheat kernels hard. Factors for favourable dough properties were identified on a few other chromosomes, different in various varieties. These were 1A of Cappelle Desprez and Cheyenne, 3B of Hope, and 2D of Timstein. All but one of these chromosomes showed an increase in loaf volume to a level in-between those of the recipient variety Chinese Spring and the donor varieties. No relationship was found between kernel hardness and dough-making and baking properties. It was assumed that wheat quality is due to a combination of kernel hardness and favourable dough-making properties. As the genes for these factors are located on different chromosomes, it should not be too difficult to introduce both factors in existing varieties with poor baking properties. In a wheat breeding programme, the quality of new lines can be assessed in a rather simple way by determining kernel hardness and dough stability.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 28
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 415-418 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; germination ; immature grains
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The results indicated that acceleration of generation time in wheat was practical. The method developed by Mukade et al. (1973) was improved by extending the hydrogen peroxide treatment at low temperature.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 29
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; chromosome substitution ; protein content ; grain weight ; genetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The 21 intervarietal chromosome substitution lines of the cultivar Hope in Chinese Spring were used to analyse the genetic differences between the two cultivars Hope and Chinese Spring in grain protein content and grain weight. Only one chromosome of ‘Hope, 5D’, significantly influenced grain protein content of ‘Chinese Spring’. Its influence was of only minor effect and was to decrease protein content expression of ‘Chinese Spring’. It has been postulated that the genetic control of protein content, in this instance, is most likely due to many genes each of small effect. Five chromosomes of ‘Hope’ influenced the 1000 grain weight value of normal ‘Chinese Spring’, all increasing its expression. Chromosomes 1A, 4A and 5B were of major effect and 3A and 6A of comparatively minor effect. A minimal estimate of five genes determines the difference in grain size between these cultivars. The possible evolutionary significance of the contribution of the A genome of bread wheat to grain size determination is discussed. On the basis of certain findings of this study, proposals are made for breeding for increased grain size in hexaploid wheat.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 30
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 769-775 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; Alternaria triticina ; leaf blight ; resistance ; genetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Genetics of field resistance to Alternaria triticina was studied in a diallel set of crosses using ten cultivars of wheat which included eight resistant and two susceptibles. Susceptibility if NP 830 was found to be controlled by a dominant gene and that of NP 891 by two dominant complementary genes. The resistant cultivars NP 824, NP 835, NP 852, C 281, E 5477, E 5550, E 5878 and UP 303 carry the recessive alleles of the genes present in NP 830 and NP 891. All the resistant cultivars used in the study carried identical gene(s) for resistance to A. triticina. The gene(s) responsible for resistance appear to have come from NP 4 and Turkey, both of which seem to have evolved simultaneously in nature. The gene(s) for susceptibility in NP 830 and NP 891 were found to be different. It is assumed that these genes come from either Motia (Triticum durum) or Khapli (T. dicoccum) in NP 830 and from Gaza (T. durum) in NP 891.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 31
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 41-50 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat harvest index ; pattern of variation ; degree of dominance ; heritability ; genetic coefficient of variation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Harvest index was studied in F1 and F2 generations of eight wheat (Triticum aestivum L.) crosses and their reciprocals. The parental varieties involved in the crosses represented a fairly wide range of character expression for plant height, tillering potential, grain yield per plant and harvest index. Differences between reciprocal crosses were not evident for the expression of harvest index of the crosses under study. Means and degrees of dominance of F1 and F2 populations suggested partial dominance of high harvest index over low harvest index. The pattern of variation among F2 segregates was quantitative and the distribution was normal. The gene action governing the expression of harvest index was largely additive. Evidence was obtained for non-additive gene action in some crosses. There was complete absence of high parent heterosis for harvest index in the F1's but midparent heterosis was found to be present in all crosses. Estimates of heritability and genetic advance were moderate to high. Usefulness of selecting for harvest index as a measure of yield efficiency particularly in early generations is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 32
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 73-82 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; Heterodera avenae ; cyst nematode ; resistance breeding
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The progress of a backcross breeding programme to introduce resistance against the cereal cyst nematode into wheat is described. Methods of resistance screening and criteria for selection are detailed and the results discussed with reference to alternative procedures for the introduction of new resistance genes into major breeding programmes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 33
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; Secale cereale ; rye ; intergeneric cross ; crossability ; pollen grain germination ; pollen tube growth
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The crossing of common wheat (Triticum aestivum L.) with rye (Secale cereale L.), and especially the action of the crossability genes of wheat, was studied using the readily crossable wheat cv Chinese Spring (genotype kr 1 kr 1 kr 2 kr 2 〉), the poorly crossable wheat cv Hope (genotype Kr 1 Kr 1 Kr 2 Kr 2 ), as well as the disomic substitution line of chromosome 5B of Hope into Chinese Spring (CS/Hope 5B, genotype Kr 1 Kr 1 kr 2 kr 2 ). By comparing crossability and actual fertilization, the poor crossability with rye of both cv Hope and the CS/Hope 5B substitution line was shown to result from absence of fertilization. Studies of pollen grain germination and pollen tube growth showed that the dominant alleles of the crossability genes manifested themselves through retardation and eventually inhibition of pollen tube growth at the style base and in the ovary wall. In Hope the growth of all pollen tubes was inhibited, whereas in CS/Hope 5B rarely fertilization was achieved. The recessive alleles of the crossability genes do not seem to have an influence on the growth of rye pollen tubes in wheat pistils.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 34
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 679-684 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; seedling emergence ; coleoptile length ; plant height ; genetic control ; phenotypic correlations ; selection
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Seedling emergence was closely correlated with coleoptile length and plant height among parents, F2 and F3, populations of crosses involving dwarf wheats Olesen Dwarf (CI 14497), Norin 10 derivative D6301, Tom Thumb derivative D6899, and the standard-height varieties Ramona 50 and Nainari 60. Genetic mechanisms that governed plant height also influenced coleoptile length, but the relative effects of genes showing dominant or epistatic effects appeared to be different. With respect to the two parents involved in each of 15 crosses, mean F2 coleoptile lengths were consistently closer to the low parent value than were corresponding mean F2 plant heights. A slight curvilinear relationship was also found between coleoptile length and plant height of F3 lines. The results suggest that selection of semidwarf wheats with long coleoptiles and improved emergence properties from crosses involving the dwarf wheats of this study would be unlikely.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 35
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 25 (1976), S. 685-691 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat flour color ; flour pigment content ; variation ; genetics
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Variation in pigment content of the flour of bread wheats (Triticum aestivum L.) was studied in the progenies of F1 and F2 of three crosses and their reciprocals. Reciprocal differences in pigment content were observed in the F1 and F2 means. Low pigment content was found to be partially dominant or over dominant in the crosses studied. There was evidence of substantial mid-parent F1 heterosis in all crosses and betterparent F1 heterosis in three crosses. In the F2, heritability estimates were moderate to high. The F2 frequency distributions were not normal. Estimation of effective factor pairs indicated the presence of one or two major gene pairs involved in the expression of pigment content in the flour. Action of modifiers was also assumed in one cross and its reciprocal. A factorial approach to metrical character suggested that the F2 segregation ratios of low pigment content to high pigment content were 3:1, 15:1, 13:3 and 9:7 for the different crosses. Utilization of the findings in a wheat breeding program is briefly discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 36
    Digitale Medien
    Digitale Medien
    Springer
    Bulletin of experimental biology and medicine 81 (1976), S. 23-25 
    ISSN: 1573-8221
    Schlagwort(e): emotional stress ; hypercholesteremia ; hypertension
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract In experiments on freely moving rabbits, exposed to prolonged (for 2 h) interrupted stimulation of negative emotiogenic zones of the hypothalamus through implanted electrodes daily for 4 months, the development of a lasting endogenous hypercholesteremia and of a mild but lasting hypertension was observed. Changes in the cholesterol concentration were greater if stimulation continued in conjunction with daily feeding of the rabbits with small doses of methylthiouracil.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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