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81.
E L Gregoraszczuk A Wojtusiak A Rózańska 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》1988,26(4):193-202
The effect of PGF2 alpha and its analogues on progesterone, estradiol and androgen production in cow corpus luteum in vitro was investigated. The cells derived from cow corpora lutea (CL) and collected in the early and middle luteal phases of the oestrus cycle were cultured as monolayers. The inhibitory effect was not apparent during the first 48 hr of culture, but appeared after this time and persisted through the remainder of the culture period. The direct luteolytic influence of PGF2 alpha was observed in the cultured cells and showed that this compound can act independently of the blood supply. 相似文献
82.
E Wielgus-Serafińska G Nowaczyk-Dura M Kamiński 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》1988,26(1):11-18
Most of the biological processes in the living organisms of both animals and man are known to be of rhythmical nature. Variability of enzymatic activity in circadian cycle depends on many factors among other on age, sexual maturity, diet as well as medication. The results obtained in our studies indicate, that the activity changes of acid phosphatase and ATP-ase Mg++ dependent in the liver of all the examined age groups were of 24 hour circadian rythm. As to the acid phosphatase activity the results of this experiments showed that in circadian cycle in all examined age groups there is only one peak of elevated activity. ATP-ase Mg++ dependent showed two activity peaks appearing at the same hour both in 30 and 60 days old animals. It should be noticed that the activities of ATP-ase Mg++ dependent in 100 day old animals were two times higher than in 30 and 60 days old rats. 相似文献
83.
Piotr Borsuk Marek Gniadkowski Ewa Bartnik Piotr P. Stępień 《Journal of molecular evolution》1988,28(1-2):125-130
Summary AllAspergillus nidulans 5S rRNA pseudogenes known so far are the result of integration of an approx. 0.2-kbp-long DNA sequence into the 5S rRNA genes. This sequence, called block C, is present in at least five copies in theA. nidulans genome and seems to be associated either with 5S rRNA genes or pseudogenes. In contrast to the 78% sequence conservation of the C-block in pseudogenes, the truncated 5 halves of the pseudogenes are very highly conserved (96.9–100%). We postulate that the 5S rRNA pseudogenes are still a subject of concerted evolution. The C-block sequence shows similarity to the switch region of the mouse heavy chain immunoglobulin gene. A characteristic motif GGGTGAG is repeated several times in both sequences; the sequence conservation is 63%. 相似文献
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88.
Molecular genetic analysis in the diagnosis of lymphoma in fine needle aspiration biopsies. II. Lymphomas versus nonlymphoid malignant tumors 总被引:1,自引:0,他引:1
J Lubiński M Chosia K Huebner 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1988,10(6):399-404
The configurations of immunoglobulin genes and T-cell receptor beta chain genes were analyzed by Southern blotting in DNA derived from nonlymphoid malignant tumors and lymphomas. Gene rearrangements were not detected in any of the 35 cases of nonlymphoid malignant tumors. On the contrary, they were shown in all 14 cases of non-Hodgkin's lymphomas, 2 of 3 cases of Hodgkin's disease and 2 cases diagnosed as non-Hodgkin's lymphoma or angioimmunoblastic lymphadenopathy. The differentiation by light microscopy between lymphoma and nonlymphoid malignant tumors was a diagnostic problem in five cases; the molecular genetic analysis of DNA was contributory in all five diagnostically difficult aspirates. By gene rearrangement studies, the diagnosis of lymphoma was confirmed in two cases and nonlymphoid malignant tumors were accurately indicated in aspirates diagnosed finally as rhabdomyosarcoma (one case) and carcinoma (two cases). 相似文献
89.
J. B. Warchol Ch. Pilgrim W. J. Ginda R. Brelińska 《Histochemistry and cell biology》1988,88(3-6):571-573
Summary Wistar rats were injected intraperitoneally with 2-(14C)deoxyglucose and their thymuses were processed for thaw-mount autoradiography after 5, 10 or 35 min. Highest levels of radioactivity were demonstrated in the thymic medulla (5-fold higher than in the cortex). Scanning of autoradiograms for regional differences in grain densities indicated particularly intense glucose utilization in the cortico-medullary zone. Differences in glucose utilization between individual thymic zones seem to reflect differences in cellular composition, i. e., ratio of stroma cells to thymocytes.Dedicated to Professor Dr. T.H. Schiebler on the occasion of his 65th birthday 相似文献
90.
J Lewin-Kowalik A L Sieroń M Krause J J Barski D Górka 《Acta physiologica Hungarica》1992,79(3):219-231
The present work has a twofold aim: 1. To ascertain whether the stimulative influence of peripheral nerve grafts on injured hippocampal neurons depends on the time lapse after transection and; 2. To examine whether the mentioned effect runs parallel to the time-dependent changes of proteins contents and composition in the submicrosomal fraction from transected rat sciatic nerves. Fluorescence microscope examination revealed that FITC-HRP labeled cells extending their neurites into the implanted peripheral nerve segments were particularly numerous among the hippocampal neurons when 7- and 35-day-old predegenegated distal stumps were used as grafts. Discontinuous SDS-slab polyacrylamide gel electrophoresis of submicrosomal fraction proteins obtained from distal stumps of rat sciatic nerves was performed at the 7, 14, 21 and 35 days after transection. Among the obtained protein fractions the most interesting seem to be the ones of 47 and 54 kDa, which reached maximal levels at the 7th day and the 50 kDa fraction with a maximum at the 35th experimental day. It is possible that the growth promoting power of the employed grafts depends on the presence of proper proteins. 相似文献