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11.
12.
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
13.
Zagrodzki Paweł Mietelski Jerzy W. Krośniak Mirosław Petelenz Barbara 《Biological trace element research》1994,(1):273-277
The aim of this work was to check whether the stable cesium content in forest litter affects the value of radiocesium from
litter-to-mushroom transfer factorTf or not. Total cesium in litter, measured by AAS, varied from 0.1–2.7 μg/g. These data, combined with earlier results for
mushrooms, showed no simple correlation forTf. More complex relationships provided very high correlation coefficients, but their validity needs further investigation. 相似文献
14.
Graźyna Zimowska Paul David Shirk Donald LeRoy Silhacek Eli Shaaya 《Development genes and evolution》1994,203(4):215-226
We describe a provitellogenic stage, a previously unrecognized stage of follicle development in moths, and show that oocytes begin yolk sphere formation prior to the development of patency by the follicular epithelium. The vitellogenic activities of follicles from pharate adult femalePlodia interpunctella (Hübner) were determined by visualizing the subunits of vitellin (YP1 and YP3) and the follicular epithelium yolk protein (YP2 and YP4) using monospecific antisera to each subunit to immunolabel whole-mounted ovaries or ultrathin sections. At 92 h after pupation, yolk spheres that contained only YP2 began to proliferate in the oocytes. The inter-follicular epithelial cell spaces were closed at 92 h making vitellogenin inaccessible to the oocyte, and consequently, the vitellin subunits were not observed in the yolk spheres. YP2 uptake most likely occurred across the brush border from the follicular epithelial cells to the oocyte at this time. At 105 h, the inter-follicular epithelial cell spaces appeared closed yet trace amounts of labeling for vitellin were observed in the spaces and also in the yolk spheres along with YP2. Equivalent labeling for all four YPs in yolk spheres was finally observed at 112 h after pupation when the follicular epithelium had become patent. These data indicate that the provitellogenic stage is an extended transition period between the previtellogenic and vitellogenic stages that lasts for approximately 13 h, and it is marked at the beginning by YP2 yolk sphere formation in the oocyte and at the end by patency in the follicular epithelium. 相似文献
15.
Anna Barańczyk-Kuźma Dorota Drobisz Kenneth L. Audus Ronald T. Borchardt 《Neurochemical research》1993,18(7):783-786
The substrate specificity and affinity of two forms of phenol sulfotransferase (PST) from Rhesus macaque brain cortex were studied. Catecholamines, their methylated metabolites (normetanephrine, metanephrine) and methylated precursor, -methylDOPA, were examined as substrates for both the cationic (PST I) and the anionic (PST II) forms of the enzyme. Sulfation of hypertensive drugs (phenylephrine, octopamine, metaraminol), hypotensive drugs (-methylDOPA, minoxidil), and related agents without a free hydroxy group on the benzene ring were also studied. Results indicated that both PST forms sulfated -methylDOPA and minoxidil, but only PST II transferred the sulfate group to catecholamines and most of the adrenergic agents examined. 相似文献
16.
Marek S. Zie¸tara Jadwiga Gronczewska Krystyna Stachowiak Edward F. Skorkowski 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,114(4):395-401
In crayfishOrconectes limosus and shrimpCrangon crangon abdominal muscle, lactate dehydrogenase (LDH, EC 1.1.1.27) is encoded by one locus. No polymorphism was detected. The enzymes were purified to homogeneity. The specific activities for purified crayfish and shrimp LDHs were 472 and 414 μmol NADH min−1 mg−1, respectively, at 30°C. Their physicochemical and kinetic properties did not resemble fish (Gadus morhua) LDH-A4 isoenzyme. Their amino acid composition indicated greater similarity to fish LDH-C4 isoenzymes. 相似文献
17.
1-acid glycoprotein (AGP) is a serum acute phase glycoprotein which possesses five N-linked complex type heteroglycan side chains which may be present as bi-, tri- and tetraantennary structures. Depending upon the content of biantennary structure on AGP, up to four glycoforms of AGP are present in serum. These glycoforms can be easily estimated in body fluids by means of crossed affinity-immunoelectrophoresis (CAIE) with the lectin, Concanavalin A (Con A). Con A selectively binds biantennary structures; the more biantennary structures on AGP, the stronger the binding. In acute inflammation, a relative increase of AGP glycoforms with biantennary units is observed - a type I glycosylation change. In some chronic inflammatory states there is an relative decrease of AGP glycoforms with biantennary heteroglycans — a type II glycosylation change. Moreover, in certain other states such as pregnancy, estrogen administration or liver damage, type II glycosylation changes are also seen. A detailed analysis of the clinical applications of the assessment of AGP glycoforms in sera of patients with rheumatic diseases, AIDS and various types of cancers is presented. Accumulated data shows that AGP glycoforms may be very useful in the detection of intercurrent infections in the course of rheumatoid arthritis, systemic lupus erythematosus, or myeloblastic leukaemia, and in the detection of secondary infections in human immunodeficiency virus infected individuals. AGP glycoforms are also very useful in differentiation between various forms of trophoblastic disease and are helpful in monitoring the treatment of these patients. Finally, AGP glycoforms provide valuable information for differentiation between primary and secondary liver cancer. 相似文献
18.
Danuta Sosnowska Andrzej Mysliwski Krystyna Dzierzbicka Aleksander M. Kolodziejczyk 《Biotherapy》1997,10(2):161-168
The modulation of NK activity by muramyl dipeptides derivatives against Ab (amelanotic) Bomirski melanoma and human erythroleukemia
K562 cells was studied in vitro. The stimulatory effect was observed for 3 of 7 muramyl dipeptides: MDP(L-Ala)C921, MDPC857
and L18-MDP(Ala) in relation to cytotoxic activity of NK cells obtained from peripheral blood and spleen of healthy and Ab
Bomirski melanoma bearing hamsters. An increased of cytotoxic activity NK cells isolated from animals before and during the
transplantable phase of the tumor against K562 was found. A similar stimulation was received for NK cells obtained from animals
against their own melanoma cells. The most significant influence of examined MDP derivatives on the cytotoxic activity of
NK cells were obtained from animals between 10 to 12 days of tumor growth. The extent of the modulation of cytotoxic activity
of NK cells was dependent on its initial value both in healthy control and Ab Bomirski melanoma bearing hamsters. If natural
cytotoxic activity was high the stimulatory effect of the examined MDP derivatives was only slightly expressed. 相似文献
19.
Krystyna Harmata 《Vegetation History and Archaeobotany》1995,4(4):235-243
The pollen diagram from Tarnowiec concentrates on human impact on vegetation, and is supported by the archaeological background. The earliest evidence of human activities dated at ca. 6500 B.P. was probably connected with the Neolithic Linearbandkeramik culture. Further periods of settlement are recorded at ca. 5200 B.P. and at 4800 B.P. The next very distinct period of intensification in human impact at ca. 4200-3800 B.P. was most certainly connected with the presence of the Corded Ware culture. The next period of settlement occurred during the late Bronze Age, in connection with the development of the Lusatian culture from ca. 3200 B.P. but is recorded only faintly in the pollen diagram. The next colonization phase at ca. 2600 B.P. is possibly the result of Scythian invasions. The widest expansion of human impact came during the period of Roman influence. After this, anthropogenic indicators decreased during the Migration period. The youngest part of the pollen diagram reveals an intensification of anthropogenic indicators connected with early Medieval settlement. 相似文献
20.