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71.
Pamela J. Letts Les Pinteric Harry Schachter 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,372(2):304-320
Golgi fractions prepared from rat testis have been shown to be enriched in the following glycoprotein glycosyltransferases: N-acetylglucosaminyltransferase, 47-fold, galactosyltransferase, 33-fold, and N-acetylglucosaminide fucosyltransferase, 15-fold. Appreciably lower transferase levels were obtained in other subcellular fractions. In the mouse, Golgi fractions were prepared from testis homogenates, testis cell suspensions and partially purified testis germinal cells; these fractions were also enriched in the above glycoprotein glycosyltransferases. Electron microscopic analysis indicated that a major portion of the total transferase activity was located in the Golgi apparatus of both rat and mouse testis although these experiments could not rule out the possible presence of some transferase activity in other organelles. 相似文献
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Morphometrisch-ultrastrukturelle Untersuchungen am Nucleus supraopticus der Ratte nach Dehydratation
Zusammenfassung Der Nucleus supraopticus der Ratte, die einer Dehydratation ausgesetzt war, wurde ultrastrukturell-morphometrisch analysiert. Dabei zeigte sich, daß die relativen Volumenanteile der einzelnen Zellkompartimente während der fünftägigen Durstperiode eine auffallende Konstanz aufweisen. Hingegen läßt sich eine absolute Zunahme der Einzelzellvolumina und somit auch der an der Synthese und Sekretion der Neurohormone beteiligten Zellkompartimente feststellen. Die vorliegenden Befunde sprechen für einen beschleunigten Abtransport des neurosekretorischen Materials bei gesteigerter Synthese. Auf eine optimale Standardisierung der Perfusionsmethode bei Untersuchungen am neurosekretorischen Zwischenhirnsystem wird hingewiesen.
Morphometric-ultrastructural investigations on the supraoptic nucleus of dehydrated rats
Summary The supraoptic nucleus of the dehydrated rat has been analysed by electron microscopy and morphometry. With that it appears, that the relative volumes of the different cell compartments are striking constant. Otherwise one can see an absolute increase of the cell volume together with the cell compartments which take part at the synthesis and secretion of the neurohormones. These results are expression of an accelerated move of the neurosecretory material during increased synthesis. The importance of an optimal standardization of the perfusion-method in investigations of the neurosecretory system is demonstrated.
Wesentliche Teile der vorliegenden Arbeit werden von H. F. Reinhardt der Medizinischen Fakultät der Universität Basel als Dissertation vorgelegt. 相似文献
75.
Ch. Garbarsch 《Histochemistry and cell biology》1969,18(2):168-173
Summary Large intestines from 30 fetuses with crown-rump lengths ranging from 26 to 180 mm have been studied histochemically as to their epithelial content of lipids. These lipids have been localized intracellularly and basally in the cells, and comparative studies of the colon and the small intestine have demonstrated that there are considerable amounts of lipids in the colon as compared with the small intestine.It is concluded that the main part of the lipids consist of saturated and unsaturated constituents.The possible explanations of the lipids as absorbed material, biological active material synthetized de novo or as material involved in the metabolism of fetal surface cells are discussed.This work was supported by a grant from the Aid of the Crippled Children, New York. 相似文献
76.
Initiation of Germination and Inactivation of Bacillus pumilus Spores by Hydrostatic Pressure 总被引:5,自引:3,他引:2
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The effect of hydrostatic pressures as high as 1,700 atm at 25 C on the heat and radiation resistance of Bacillus pumilus spores was studied. Phosphate-buffered spores were more sensitive to compression than spores suspended in distilled water. Measurements of the turbidity of suspensions, the viability, refractility, stainability, dry weight, and respiratory activity of spores, and calcium and dipicolinic acid release were made for different pressures and times. Initiation of germination occurred at pressures exceeding 500 atm and was the prerequisite for inactivation by compression. The rate of initiation increased with increasing pressure at constant temperature. This result is interpreted as a net decrease in the volume of the system during initiation as a result of increased solvation of the spore components. 相似文献
77.
Summary Ganglia from Auerbach's plexus of the large intestine (caecum, appendix vermiformis, colon transversum and rectum) in man, rhesus monkey and guinea-pig are composed of nerve cells and their processes, typical Schwann cells and a vast neuropil. The neuropil consists of dendrites and axons of intrinsic nerve cell perikarya and axons of extrinsic neurons. Axonal profiles in large nerve fibre bundles are of uniform size and appearance, embedded in infoldings of Schwann cell cytoplasm and contain occasional large granular vesicles, mitochondria and neurotubules. Preterminal axons widen into vesicle filled varicosities, some of which establish synaptic contact with intrinsic nerve cell bodies.At least three different types of neuronal processes can be distinguished in the myenteric neuropil according to the size, appearance and commutual proportion of vesicles present in axonal varicosities, and their ability to accumulate exogenous 5- and 6-hydroxydopamine and 5-hydroxydopa: 1. Axonal enlargements containing a major population of small electron lucent synaptic vesicles (350–600 Å in diameter) together with a small number of membrane-bound, opaque granules (800–1,100 Å). These profiles have been identified as cholinergic axons. The boutons establish synaptic contacts with dendritic processes of intrinsic nerve cell bodies; membrane specializations are found at the preand postsynaptic sites. 2. Axonal beads of sometimes very large diameter, containing an approximately equal amount of large granular vesicles (850–1,600 Å) and small, electron lucent or faintly opaque vesicles (400–600 Å). The granular core of the large vesicles is of medium electron density and may either fill the entire vesicle or is separated from the limiting membrane by a more or less clear interspace. The fibres probably belong to intrinsic neurons, and because of the similarity of the large, membrane-bound vesicles with neurosecretory elementary granules, they have been designated p-type fibres (polypeptide fibres). The granular core of the vesicles in these fibres becomes more electron dense after treatment with 5-OH-dopa. The accumulation of an amine precursor analogue in combination with a possible storage of a polypeptide substance (or an ATP-like substance) resembles the situation in several diffusely distributed endocrine cell systems. 3. Varicosities of axons equipped with small (400–600 Å) empty or sometimes granular vesicles, medium sized (500–900 Å) vesicles with highly electron dense cores and occasional large (900–1,300 Å) granular vesicles. Pretreatment with 5-OH-dopamine increases the electron density in almost all medium-sized granular vesicles and some of the large granular vesicles; an osmiophilic core develops in some small vesicles. 6-hydroxydopamine results in degenerative changes in the varicosities of this type of neurons. Concomitantly, both catecholamine analogues markedly reduce neuronal noradrenaline in the large intestine, as demonstrated by fluorescence histochemistry and in fluorimetric determinations. The ultrastructural features of these varicosities and their reaction to 5- and 6-OH-dopamine indicate that they belong to adrenergic, sympathetic nerves. No membrane specializations could be detected at sites of close contact of the adrenergic boutons with dendrites and cell bodies of intrinsic nerve cells.Supported by grants from the Deutsche Forschungsgemeinschaft.Supported by a grant from Albert Pahlsson's Foundation, Sweden. The work was carried out within a research organization sponsored by the Swedish Medical Research Council (projects No. B70-14X-1007-05B, B70-14X-712-05, and B70-14X-56-06). 相似文献
78.
A marked increase in the isolation of Group B streptococci from patients in the University Hospital, Saskatoon, has been noted over the past four years, and no change in technical methods has been found to explain this increase. Group B streptococci have been isolated from 242 patients, in 53 of whom the streptococcus was considered the cause of the infection. Infections occurred predominantly in the urinary tract, female genital tract and upper respiratory tract. There was a low incidence of infections in newborn infants, and only four infections were in patients under 1 year old. Infections were more frequent in women than men and in patients over 40 years of age. No particular affinity of Group B streptococci for diabetics was demonstrated. 相似文献
79.
80.
Conclusions Incubation of competent cells ofB. subtilis with a DNA-like subviral entity from vaccinia virus leads to the formation of complete vaccinia virus in the bacteria. The significance of this finding in regard to the concept of a universal genetic code is discussed.With 2 Figures in the TextA preliminary report of these results was presented at the XI. International Congress of Genetics in The Hague, September, 1963.Habilitandenstipendiat 1962/63 of Deutsche Forschungsgemeinschaft. 相似文献