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121.
Differential distribution of dihydrotestosterone and estradiol binding sites in the epididymis of the mouse 总被引:1,自引:0,他引:1
Summary The distribution of androgen and estrogen binding sites in the mouse epididymis was assessed by autoradiography with 3H dihydrotestosterone (3H DHT) and 3H estradiol (3H E2). Nuclear labeling with 3H DHT in principal cells of the epithelium is high in the caput, low in the corpus, and high again in the cauda. 3H E2 also binds to the nuclei of principal cells. The pattern is distinct from 3H DHT: nuclear labeling is highest in the ductulus efferens and high in the caput, but low or absent in corpus and cauda. Apical cells in caput and clear cells in corpus and cauda are moderately labeled with 3H DHT but heavily labeled with 3H E2. Connective tissue cells show variable labeling with both hormones, being more pronounced with 3H E2. Smooth muscle cells are also labeled to varying degrees with both hormones.The different binding patterns of 3H DHT and 3H E2 and the results of the competition studies with unlabeled compounds demonstrate that in the epididymis besides the specific nuclear receptors for androgen also estrogen receptors are present.Supported by US P.H.S. grant NS 09914 and Deutsche Forschungsgemeinschaft Dr 94/4 相似文献
122.
Transcriptional activation and nuclear targeting signals of the human androgen receptor 总被引:28,自引:0,他引:28
J A Simental M Sar M V Lane F S French E M Wilson 《The Journal of biological chemistry》1991,266(1):510-518
123.
Composite structure of the human thyrotropin receptor gene 总被引:9,自引:0,他引:9
B Gross M Misrahi S Sar E Milgrom 《Biochemical and biophysical research communications》1991,177(2):679-687
124.
The supernatant fluids of cultures of four bacterial strains isolated from the skin of barracuda contained extracellular polymer concentrations of 0.2–0.5 mg/ml and reduced factional drag by 2.5–22% in a turbulent flow rheometer. The production and properties of one of the drag-reducing polymers, referred to as PS-6, were studied further. Polymer PS-6 was produced by strain NS-31 in minimal salts medium supplemented with ethanol or glucose. The polymer began to accumulate in the culture medium during exponential phase and continued to be produced during stationary phase. It reduced drag by 55% at a concentration of 0.75 mg/ ml. Acid-base titration of the deproteinized polymer PS-6A gave two inflection points: pK1=3.26 (2.4 eq/mg) and pK2=9.66 (0.8 eq/mg).13C-NMR spectroscopy of PS-6A resolved 25 peaks, including three methyl groups, three carbonyl groups, and four signals in the anomeric region (99–103 ppm), indicating the presence of four different monosaccharides. Strong acid hydrolysis of PS-6A yielded an amino acid, pyruvate, and four reducing sugars: a hexosamine, a uronic acid, and two hexoses which migrated on TLC similarly to glucose and galactose. The possible role of bacteria in production of drag-reducing mucus is discussed. 相似文献
125.
Frederic A. Reid Ye Soon Kim Walter E. Stumpf Michael E. Selzer Madhabananda Sar 《Acta zoologica》1980,61(4):247-253
Reid, F. A., Kim, Y. S., Stumpf, W. E., Selzer, M. E., Sar, M. 1980. Autoradiographic studies with 3H estradiol in the body of lamprey, Ichthyomyzon unicuspis. (Departments of Anatomy and Pharmacology, University of North Carolina, Chapel Hill, North Carolina, and Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, U.S.A.) — Acta zool. (Stockh.) 61 (4): 247–253. Female and male lampreys, Ichthyomyzon unicuspis, in the parasitic feeding stage were injected with 3H estradiol-17β. Autoradiograms were prepared from the trunk region of animals sacrificed 2.5 hours after injection. Nuclei of cells show concentrations of radioactivity which can be abolished with pre-injection of unlabeled estradiol. 3H estradiol-concentrating cells are found in connective tissues associated with aorta, cardinal veins, muscle septa, dermis, intestine, kidney, and ovary, as well as in kidney tubules, epithelial lining of the body cavity, epidermis and notochord. The results demonstrate the extensive presence of estrogen target cells in this cyclostome. These estrogen target sites correspond to tissues known to undergo drastic morphological changes during the spawning migration. 相似文献
126.
Summary Immunocharacteristics of the pars distalis cells of the pituitary of the male lizard A. carolinensis are determined by employing the immunoperoxidase technique with antisera to mammalian pituitary hormones. On the basis of their immunoreactivity, 5 different cell types with characteristic anatomical distribution are recognized. ACTH cells are found in the rostral half of the pars distalis, and PRL cells in the rostral two thirds of the pars distalis. GH and TSH cells are located in the caudal half of the pars distalis. GTH cells are distributed throughout the gland. When consecutive sections are stained with antiserum to ovine FSH or its -subunit and to ovine LH, the same cells show immunoreactivity to all the three antisera. None of the GTH cells show positive immunoreactivity to ovine -LH antiserum. The results suggest the existence of one gonadotropic cell type in the pituitary of this lizard.Supported by U.S. Council for International Exchange of Scholars (to D.R.N.) and PHS Grant NS09914 相似文献
127.
Summary After intravenous injection of 3H-estradiol in the 12-day old chick embryo, radioactivity is concentrated in nuclei of certain cells in the cloacal area. The nuclear labeling is observed in mesenchymal cells along the different portions of the cloaca, and in an unidentified tissue located laterally to the cloaca. The labeled mesenchymal cells display a definite pattern of distribution along the epithelial wall of the cloaca, identical both in male and in female embryos. In the adjacent bursa of Fabricius, cells do not concentrate labeled hormone in their nuclei. The presence of estrogen receptors in the cloacal area of embryos of either sex adds evidence, at the cellular level, to support the concept of a neutral, or undifferentiated, sex with estradiol inhibiting this neutral male differentiation.Visiting scientistSupported by a Fellowship from the Délégation Générale à la Recherche scientifique et technique, Paris, France 相似文献
128.
Sureyya Sarıhan Ahmet Sami Bayram Cengiz Gebitekin Omer Yerci Deniz Sıgırlı 《Reports of Practical Oncology and Radiotherapy》2018,23(2):97-104
Aim
The aim of this study was to evaluate thymic epithelial tumors (TETs) for treatment outcomes and prognostic factors on survival.Background
TETs are very rare neoplasms and multidisciplinary approach is recommended according to prognostic factors.Materials and methods
Between 1995 and 2013, 31 patients were treated with median 5400 cGy (range: 1620–6596 cGy) radiotherapy (RT). Eleven patients received adjuvant or concurrent chemotherapy. There were 25 thymomas, 4 thymic carcinomas and 2 thymic neuroendocrin carcinomas. According to Masaoka, staging and WHO classification, cases were divided to good (n: 10), moderate (n: 9) and poor (n: 12) prognostic risk groups. Survival was calculated from diagnosis.Results
In January 2016, 22 cases were alive with median 51.5 months (range: 2–170.5) follow-up. Recurrences were observed in 29% of patients in median 29.5 months (range: 6.5–105). Local control, mean overall (OS) and disease-free survival (DFS) rates were 86%, 119 and 116 months, respectively. There was a significant difference for R0 vs. R+ resection (81% vs. 43%, p = 0.06, and 69% vs. 46%, p = 0.05), Masaoka stage I–II vs. III–IV (75% vs. 52%, p = 0.001, and 75% vs. 37%, p < 0.001), and also prognostic risk groups (100% vs. 89% vs. 48%, p = 0.003, and 100% vs. 87% vs. 27%, p = 0.004) in terms of 5-year OS and DFS, respectively.Conclusion
In our study, prognostic risk stratification was shown to be a significant predictor of survival. There is a need to investigate subgroups that may or may not benefit from adjuvant RT. 相似文献129.
Sibel Erdoğan Serhat Karaca Mehtap Güney Aşkın Kor Cihan Çakmakçı Muammer Sarıbey 《Archives of animal nutrition》2018,72(5):351-367
This study aimed to evaluate the effects of adding dried distillers’ grains with solubles (DDGS) to the nutritional regimens of ewes at different time periods on reproductive traits, serum hormones and serum metabolites. In Experiment 1, 100 ewes were divided into 4 groups (n = 25) according to diet. The four diets were grass hay (H) alone (group H), H with barley (group H + B), H with DDGS for the whole feeding period (27 d) (group H + DDGS) or H and DDGS for 5 d (d 8–12 of oestrus cycle) (group H + DDGS5). Serum progesterone concentrations were affected by oestrus cycle (p < 0.001), but not by dietary treatments. However, feeding H + DDGS caused significant increases in serum insulin, leptin and growth hormone concentrations (p < 0.05). In Experiment 2, 30 ewes were divided into 2 groups (n = 15), receiving DDGS or soybean meal (SBM) during the prepartum period. Diets had no significant effect on weights of dams or lambs at birth; however, the weaning weights of lambs born from ewes of group DDGS were significantly higher (p < 0.05). Moreover, serum glucose, blood urea nitrogen, triglyceride and beta hydroxybutyric acid (BHBA) concentrations during the prepartum period were affected by dietary treatments and by time (p < 0.001). During the prepartum period, BHBA concentrations of ewes fed SBM were higher, while BHBA levels decreased during the last weeks of pregnancy regardless of diet. Lamb serum immunoglobulin G concentrations increased from 1 h to 24 h after birth (p < 0.001). Colostrum of ewes fed SBM had higher fat-free dry matter (DM) and protein contents in comparison to colostrum of ewes fed DDGS (p < 0.05). In conclusion, DDGS can be included as protein source in pregnancy rations up to 15% of DM to obtain reproductive performance outcomes equal to or exceeding those obtained with SBM. 相似文献
130.
Arindam Samanta Achintya Mahanti Souvick Chatterjee Siddhartha Narayan Joardar Samiran Bandyopadhyay Tapas Kumar Sar Guru Prasad Mandal Tapan Kumar Dutta Indranil Samanta 《Annals of microbiology》2018,68(11):781-791
The present study was undertaken to detect the occurrence of beta-lactamase-/AmpC-producing Klebsiella and Escherichia coli in healthy pigs, feed, drinking water, and pen floor or surface soil. The study also intended to detect the clonal relationship between the environmental and porcine isolates to confirm the route of transmission. Rectal swabs and environmental samples were collected from apparently healthy pigs kept in organized or backyard farms in India. The pigs had no history of antibiotic intake. Production of phenotypical beta-lactamase, associated genes, and class I integron gene was detected in E. coli and Klebsiella isolates. The phylogenetic relationship among the isolates was established on the basis of Random amplification of polymorphic DNA banding pattern. Beta-lactamase-producing Klebsiella were isolated from healthy pigs (20.0%), pen floor swabs/surface soil swabs (14.0%), and drinking water (100%). Escherichia coli isolated from healthy pigs (14.4%), pen floor/surface soil (8.0%), and drinking water (33.3%) were detected as beta-lactamase producers. Majority of beta-lactamase-producing isolates possessed blaCTX-M-9. Further, 35 (81%) Klebsiella and all the E. coli isolates were detected as AmpC beta-lactamase ACBL producers and possessed blaAmpC. Sixteen beta-lactamase-producing Klebsiella (37.20%) and 13 E. coli (86.67%) possessed class I integron. Few resistant isolates from environmental sources (surface soil swab and drinking water) and the studied pigs were detected within the same cluster of the dendrogram representing their similarities. The study indicated about the possible role of contaminated environment as a source of beta-lactamase/AmpC-producing Klebsiella and E. coli in pigs. 相似文献