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81.
Dr. Christoph Schubert 《Cell and tissue research》1974,156(1):103-112
Summary Dorsal tubercle and skin of Mertensiella caucasica have been investigated with the electron microscope and enzyme histochemical methods. The epidermis of the tubercle consists of 8–9 cell layers, that of normal dorsal skin of 5–6. The tubercle is filled with large mucous glands which are surrounded by an almost complete layer of smooth muscle cells (myoepithelial cells). Their glandular cells undergo cyclical changes and are characterized by specific secretory granules, which differ from those of the relatively small mucous glands of the normal dorsal skin.In the connective tissue of the tubercle a relatively rich supply of nerve fibres has been found, which in part contain synaptic and dense core vesicles or accumulations of mitochondria. In the normal dorsal skin nerve fibres occur less frequently.The following enzymes have been demonstrated in the mucous glands of the tubercle: SDH, acid phosphatase, unspecific esterases, E 600 resistant esterase.The tubercle seems to stimulate the female cloaca chemically and mechanically. 相似文献
82.
83.
As a consequence of polyploidization, the carp is endowed with three genetic loci coding for LDH in most tissues (and additional ones in liver). However, each such duplicated gene may not be functionally essential for the organism and could be eliminated. In a population survey, an electrophoretic polymorphism was detected which may best be interpreted by the assumption of a null allele, which is apparently not subject to selective pressure. Thus this originally duplicated gene would have diverged in the course of evolution without the origin of differences in function, so that one or the other of the genes is dispensable. 相似文献
84.
Dielectric properties of hemoglobin and myoglobin. I. Influence of solvent and particle size on the dielectric dispersion 总被引:2,自引:0,他引:2
Dielectric dispersion measurements with aqueous solutions of hemoglobin and myoglobin have been performed in the frequency range from 100 kcps to 15 Mcps. The influence of preparation, particle size, and solvent conditions was studied. The results are analyzed in terms of an orientational polarization mechanism. 相似文献
85.
86.
Tissues were obtained by open biopsy of a series of human intracranial neoplasms, fixed in Veronal-buffered osmium tetroxide, and embedded in Vestopal-W. In two instances in which specimens were obtained from oligodendrogliomas in regions where the tumor had infiltrated but not entirely destroyed cortical tissues, glial processes were found to be arranged in a highly organized laminar fashion. This feature was not observed in two additional oligodendrogliomas nor in other types of intracerebral neoplasms. Three types of laminar structures were recognized: (a) perikaryal sheaths composed of several layers of overlapping or concentrically orientated glial processes, (b) layers of longitudinally orientated glial processes along the outer aspect of myelinated axons, and (c) small laminated figures composed of several concentrically disposed glial processes. Spirally constituted lamellar systems were not demonstrated. These findings indicate that under certain circumstances glial cells have the capacity to form sheaths and sheath-like structures by concentric lamination of several processes, rather than by spiraling of a single process. 相似文献
87.
Ohne ZusammenfassungTeile dieser Arbeit wurden von Fräulein M. Kurth im Rahmen ihrer medizinischen Doktordissertation erarbeitet.Die Untersuchungen der Verfasser zum Mutationsproblem werden durch die Deutsche Forschungsgemeinschaft gefördert. 相似文献
88.
89.
Zusammenfassung In den verschiedenen Zellarten im Gebiet der neuro-muskulären Synapsen des mit OsO4 fixierten Maus-Diaphragmas werden Mikropinozytose-Vesikel dargestellt, die durch eine besondere Membrandifferenzierung ausgezeichnet sind. Vorkommen, Feinstruktur und Entstehung dieser coated vesicles werden beschrieben. Ihre mögliche Funktion sowie die Bedeutung des Saumes werden in Zusammenhang mit der bereits vorliegenden Literatur diskutiert.
Wir danken dem Schweizerischen Nationalfonds zur Förderung der wissenschaftlichen Forschung (Nr. 3806) für die Unterstützung dieser Arbeit. 相似文献
Summary Coated vesicles were demonstrated in various cell types in the region of the neuro-muscular junctions of the mouse diaphragm fixed with osmium tetroxide. These vesicles are characterized by a membrane which is specially differentiated. The occurrence, fine structure, and formation of these coated vesicles are described; their possible function and the nature of the coat are discussed in the light of existing literature.
Wir danken dem Schweizerischen Nationalfonds zur Förderung der wissenschaftlichen Forschung (Nr. 3806) für die Unterstützung dieser Arbeit. 相似文献
90.
A Rapid Screening Test for Aflatoxin-synthesizing Aspergilli of the flavus-oryzae Group 总被引:1,自引:1,他引:0
P. de Vogel Renée van Rhee W. A. A. Blanche Koelensmid 《Journal of applied microbiology》1965,28(2):213-220
A rapid test for the recognition of aflatoxin-synthesizing strains of the Aspergillus flavus–oryzae group is described. For this purpose the strains are cultivated on Czapek–Dox agar enriched with an aqueous extract of groundnuts, and in which sodium nitrate is replaced by ammonium chloride. Toxin production is observed by the production of a bright blue fluorescence in the medium when placed under an ultraviolet lamp. 相似文献