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161.
162.
Jan Zarzycki Alina Peryt Barbara Klubińska Teresa Hajac Krystyna Żak 《Histochemistry and cell biology》1969,18(4):314-320
Zusammenfassung Es wurden mit histochemischen Methoden Milchdrüsen von Meerschweinchen in physiologischer und durch Kastration während der Laktationsperiode hervorgerufener Involution untersucht. Nachgewiesen wurden alkalische und saure Phosphatase (APh und SPh), unspezifische Esterase, Sukzinodehydrase, SH-Gruppen, Nukleinsäuren und Lipide. — Die Aktivität der SPh nimmt während der Involution zu. Die Bedeutung dieses Enzyms für den Rückbildungsprozeß des Drüsengewebes wird diskutiert. — Das Vorkommen der APh-Aktivität in Drüsenendstücken im Involutionsstadium kann auf die Beteiligung dieses Enzyms an der Rückresorption der mit der Milch ausgeschiedenen Substanzen hinweisen. — Zwischen der Aktivität der unspezifischen Esterase und dem Gehalt sowie der Lokalisation von Lipiden besteht eine Abhängigkeit. — Es konnten keine Unterschiede in der Sukzinodehydraseaktivität und dem DNS-Gehalt aufgezeigt werden. — Die Verminderung von SH-Gruppen und RNS hängt mit dem Aufhören der Sekretionsproduktion durch die Zellen der Drüsenendstücke der Milchdrüsen zusammen.
Histochemical studies on the involution mechanism of the mammary gland
Summary Histochemical methods were used to study mammary glands of guinea pigs in the course of physiologic involution and that induced by castration during lactation. Alkaline and acid phosphatases, unspecific esterase, succinic dehydrogenase, SH groups, nucleic acids and lipids were determined. Acid phosphatase activity was found to be increased in mammary glands, subject to involution. The participation of the enzyme in the involutionary process of the gland tissue is discussed. The distribution of alkaline phosphatase in the secretory sections of the gland during involution would suggest the participation of the enzyme in the reabsorption of the substance secreted with milk. A correlation existing between the activity of unspecific esterase, the level and distribution of lipids in the mammary gland could be established. No differences were detected in the activity of succinic dehydrogenase and DNA level. A decrease in SH groups and RNA content is related to cessation of milk secretion.相似文献
163.
164.
165.
166.
K Marczyński J Cielecki A Balasz 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1967,22(50):1935-1936
167.
B. Bilińska 《Histochemistry and cell biology》1989,93(1):105-110
Summary Effect of LH, vinblastine and cytochalasin B on the cytoskeleton of cultured Leydig cells was investigated using monoclonal antibodies and fluorescence microscopy. After LH addition and treatment with cytoskeletal disrupting drugs, three main effects were observed: 1) increase of androgen level secreted by cultured mouse Leydig cells, 2) changes of cell-shape towards regular and rounded, 3) increase of 5,3-HSD activity. The results are discussed in respect to possible involvement of cytoskeleton in the regulation of steroidogenesis. 相似文献
168.
W Gasiorowski T Krzemińska W Ostrowska J Woy-Wojciechowski 《Endokrynologia Polska》1989,40(4):199-212
Scintigraphic and gammagraphic (gamma-camera) techniques have been applied in diagnosing "hot" non-TSH dependent thyroid nodules. On the basis of frequent uneven accumulation of isotopic tracer observed in scintigraphic studies it was concluded that the structure of these nodules is heterogeneous. In some cases paradoxical patterns have been obtained following the dynamic tests of suppression and stimulation of the thyroid: after the administration of thyroid preparations paranodular thyroid tissue appears, while TSH administration causes an increase in the iodine uptake by the nodule. Ultrasonographic and gamma-camera studies have been carried out in 50 cases of "hot" autonomic thyroid nodules previously diagnosed by scintigraphy. Ultrasonographic studies revealed a weaker echogenicity in some cases and an intensified echo in the other. Sometimes by using this technique it was possible to demonstrate the occurrence of heterogeneous structures suggesting a cystic degeneration of the nodule. Paranodular thyroid tissue, invisible in scintigraphic scanning, could usually be observed by applying gamma-camera. It was concluded that both gamma camera and ultrasonographic studies confirm heterogeneous structure of intranodular tissue producing paradoxical patterns in scintigraphic scanning, with the latter technique usually aiding the detection of paranodular thyroid tissue without the necessity of application of the TSH test. 相似文献
169.
A Kasprowicz J Owsiński A Bia?ecka P B Heczko 《Medycyna do?wiadczalna i mikrobiologia》1990,42(3-4):108-115
In this study a participation of anaerobic bacteria in respiratory tract diseases is presented. Bronchial washings collected by ++fibrobronchoscope constituted material for the study. Immediately after collection the material was plated onto two media for aerobic bacteria (hemomedium) and anaerobic bacteria (anaeromedium). Then, the samples were centrifuged and a sediment was plated on solid media suitable for aerobic and anaerobic bacteria. Bacterial anaerobic isolates were identified by using API 20E and their sensitivity to antibiotics was tested. From the material described above the most frequently isolated anaerobic bacteria were such as: Streptococcus intermedius, Bacteroides melaninogenicus, Veilonella sp. Among aerobic bacteria the most frequently isolated were Gram-negative rods, Streptococcus faecalis, Branhamella catarrhalis. It is worth to underline that in about 25% of cases anaerobic bacteria were the only isolates. 相似文献
170.
Summary During cell division in antheridial filaments ofChara vulgaris an increase in DNA content occurs in both shield cells and manubria within an antheridium, reaching 16C–64C and 8C–32C levels, respectively. Endoreplication ceases prior to the formation of spermatids and initiation of spermiogenesis, probably as a result of symplasmic isolation of the antheridium from the thallus. As the DNA content of the nuclei increases, the shield cells3H-leucine incorporation increases, and they grow intensively in the tangential plane. Translation decreases considerably after termination of shield cell growth. DNA content of mature manubria is half of that in shield cells, although their size is 10 times that of manubria. Translational activity of manubria also increases as DNA content rises and cells grow. However, during spermiogenesis, this activity remains at its maximum, which is associated with the secretory function of the manubria. Spermiogenesis is also accompanied by far-reaching ultrastructural changes within the manubrial cytoplasm.The level of endopolyploidy in both shield cells and manubria of antheridia formed in the spring is higher by one replication cycle, than in autumnal antheridia. AMO-1618, at a concentration of 10–5M reduces the DNA content in the autumnal manubria. The higher the manubrial level of endopolyploidy in spermiogenesis, the greater their size, and the higher the translational activity and number of joined spermatids. The number of spermatozoids in the antheridium is also positively correlated with the internal volume of an antheridium, which is itself dependent on the endopolyploidy level of shield cells.The results obtained confirm the assumption that endoreplication favours the higher growth dynamics and potential translational activity, which occurs in the dynamic growth phase only in shield cells, while in manubria, i.e. cells producing substances necessary to spermatozoids development, it remains high until the end of spermiogenesis. 相似文献