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131.
Assessment of oestrogenic potency of chemicals used as growth promoter by in-vitro methods 总被引:7,自引:0,他引:7
Three in-vitro bioassays were used to compare the oestrogenic potency of chemicals used as growth promoter in beef cattle in certain non-European Union countries (17beta-oestradiol, alpha-zearalanol, testosterone, trenbolone, trenbolone acetate, melengestrol acetate) or found as food contaminant such as the mycotoxin zearalenone and some of their metabolites (17alpha-oestradiol, oestrone, 17alpha-epitestosterone, 19-nortestosterone, androstendione, zearalanone, alpha-zearalanol, beta-zearalanol, alpha-zearalenol, beta-zearalenol). The strong oestrogens 17alpha-ethinyl oestradiol and diethylstilboestrol were used as standards. The first bioassay was based on the activation of a reporter gene by oestrogens in recombinant yeast expressing human or rainbow trout oestrogen receptor. In the second bioassay, the vitellogenin gene induction of rainbow trout hepatocyte cultures was used as a biomarker for the exposure to oestrogens. The third bioassay was based on the alkaline phosphatase gene induction by oestrogens in the human endometrial Ishikawa cell line. The assessment of oestrogenic potency of these chemicals clearly demonstrates the strong oestrogenicity of the mycotoxin zearalenone and its metabolites and particularly alpha-zearalenol which was as potent as ethinyl oestradiol and diethylstilboestrol in the human endometrial Ishikawa cell line. 相似文献
132.
Yu. P. Denisov P. V. Sergeev N. P. Saksonov G. V. Shutko 《Bulletin of experimental biology and medicine》1980,89(2):147-150
Parameters of binding of cortisone and estradiol to plasma membranes of rat hepatocytes were studied by the method of liquid scintillation radiometry. The presence of two systems for the binding of these hormones in the membranes was demonstrated. One system is specific (saturable) and binds hormones in physiological concentrations. The capacity and affinity of this system for cortisone are significantly higher than for estradiol. The binding parameters within the temperature range from 4 to 37°C for cortisone and estradiol respectively are: Dissociation constant 2.1–3 and 2.7–4.5 nM, number of binding sites 2–2.4 and 0.14–0.18 nmoles/mg protein. Experiments with p-chloromercuribenzoate demonstrate the role of proteins in the working of this system. The second (unsaturable) system is nonspecific and its function is determined by the lipid component of the membranes. The affinity of corticosteroids for hepatocytes is probably due to the activity of the (saturable) specific system of the plasma membranes of these cells.Department of Molecular Pharmacology and Radiobiology, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Yudaev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 2, pp. 172–174, February, 1980. 相似文献
133.
Per Jensen M.D. Søren Buus Jensen M.D. Per Soelberg Sørensen M.D. Birgitte D. Bjerre M.D. Dominick A. Rizzi M.D. Anne Stub Sørensen M.D. Rene Klysner M.D. Kim Brinch M.D. Bo Jespersen M.D. Henrik Nielsen M.D. 《Archives of sexual behavior》1990,19(1):1-14
Sexual dysfunction is a well-known complication of chronic somatic illness. Eighty-six consecutive epileptic outpatients, 38 men and 48 women, without accompanying disorders, were studied. The frequency and symptoms of sexual dysfunction were compared with results from previous studies using identical sexological methodology. The previous studies were of diabetic patients and healthy controls. Eight percent of the epileptic men reported a sexual dysfunction compared to 44% of the diabetics and 13% of the controls. Epileptic women, diabetic women, and controls showed no significant differences in sexual dysfunction (29%, 28%, and 25%, respectively). In both sexes, the sexual function measured by frequencies of coitus and masturbation was normal. Most patients had good control of epileptic attacks on a treatment of monotherapy. Hormonal status was generally within normal limits in both men and women; only a few minor differences were found and they showed no correlation with sexual dysfunction. Psychologically and socially the patients did not differ appreciably from normals, and they exhibited a high degree of disease acceptance. This study, using a biopsychosocial approach in understanding sexual dysfunctions, is in contrast with previous, mainly uncontrolled, studies of epileptic patients that reported high frequencies of hyposexuality in males. We conclude that epilepsy does not necessarily increase the risk of sexual dysfunction in male or female. 相似文献
134.
垂体hGH分泌受中枢神经介质调控。兴奋胆碱能系统可使hGH增加。本文试用胆碱酯酶抑制剂吡啶斯的明兴奋hGH,并与胰岛素兴奋试验进行比较,观察了13名正常青少年和10名垂体性侏儒症患者对两种兴奋试验的反应。结果显示口服吡啶斯的明2mg/kg体重能迅速有效地兴奋垂体hGH释放。其作用较胰岛素兴奋试验更强,是一项值得推荐的判定青少年垂体hGH储备功能的试验。 相似文献
135.
目的 :了解促排卵治疗对黄体中期子宫内膜雌激素受体 (estrogenreceptor,ER)、孕激素受体 (progesteronereceptor,PR)及其mRNA表达的影响。方法 :应用光学显微镜检测着床窗口子宫内膜、采用免疫组化及原位杂交方法检测正常及多囊卵巢综合征 (polycysticovariansyndrome ,PCOS)妇女促排卵治疗后子宫内膜黄体中期ER、PR及其mRNA的表达 ,放射免疫法测定同期血中雌激素 (estradiol,E2 )及孕激素 (progesterone,P)水平。 结果 :正常妇女黄体中期子宫内膜组织形态 2 2例中有 2 0例为分泌中期改变 ,2例为分泌早期改变。ER、PR弱表达 ,ERmR NA及PRmRNA的表达也较弱 ,而PCOS妇女治疗后黄体中期氯米芬 9/人绒毛膜促性腺激素组及氯米芬 /绝经期促性腺激素 /人绒毛膜促性腺激素组各 15例分别有 8/ 15及 7/ 15光镜下为分泌中期改变 ,其它为分泌早期改变。ER、PR的表达增强 ,其基因的表达也明显增强 ,血清P的水平相对较低。促性腺激素释放激素激动剂 /绝经期促性腺激素 /人绒毛膜促性腺激素组共 10例 ,E2 、P及P/E2 接近对照组 ,上述标志物的表达与对照组相似。但 3组PCOS分泌中期子宫内膜均有不同程度的间质增生、致密 ,腺体与间质发育不同步 ,且间质致密处ER、PR及其mR NA表达均下降。结论 :氯米芬 /人绒毛膜促性腺 相似文献
136.
目的 观察儿童体外循环心脏手术前后甲状腺激素的变化,了解体外循环心脏手术对儿童甲状腺功能的影响并探讨其临床意义。方法 用放射免疫方法测定25例外循环心脏手术儿童术前、术中、术后甲状腺激素和促甲状腺激素的含量。结果 体外循环期间血浆三碘甲状腺原氨酸(tetrodothyronine,T3)、游离三碘甲状腺原氨酸(frii triiodothyronine,FT3)、四碘甲状腺原氨酸(tetraiod 相似文献
137.
类固醇激素在变应性鼻炎治疗中的应用 总被引:1,自引:0,他引:1
目的:对类固醇激素在变应性鼻炎治疗中的应用作一综述,方法:对类固醇激素在变应性鼻炎治疗中的应用加以分析,整理。结果:展现类固醇激素在变应性鼻炎治疗领域的最新成果,结论:选择合适的应用方法,有地临床医师运用类固醇激素在主为应性鼻炎的治疗中提高疗效,避免或尽量减少副作用的发生。 相似文献
138.
目的 探讨沂蒙山区新生儿血液中甲状腺激素的水平和碘缺乏状态 ,为消灭新生儿碘缺乏症提供依据。方法 利用放射免疫 (或免疫放射 )分析方法 ,对沂蒙山区 2 0 0 0例新生儿脐血中TT3、TT4 、FT3、FT4 、rT3、TSH进行综合检测。结果 男女两性新生儿脐血中的甲状腺激素和促甲状腺激素无显著性差异 ;山区居民新生儿脐血中TT3、TT4 、FT3、FT4 、rT3 值均低于城镇居民新生儿 ,TSH值高于城镇居民新生儿 ,山区与城镇居民新生儿脐血中的TT3、TT4 之间存在显著性差异 (P <0 .0 5) ;有 6例 ( 0 .30 % )新生儿存在缺碘状况。结论 检测新生儿脐血中TT4 、FT4 、TSH ,是判断新生儿是否存在碘缺乏的重要依据。 相似文献
139.
140.
目的:探讨鼻咽血管纤维瘤与体内性激素的临床关系。方法:采集24例鼻咽血管纤维瘤患手术后外周静脉血标本(术前24例,术后20例)及24例健康男性青年作为对照组,用放射免疫测定法分别检测鼻咽血管纤维瘤患手术前后对照组血清性激素水平。结果:(1)鼻咽血管纤维瘤患手术前后血清性激素水平变化不大(P>0.05);(2)血清雌二醇,孕酮术前水平较正常对照组低(P<0.05),血清睾酮术前水平与正常对照组水平变化不大(P>0.05);(3)鼻咽血管纤维瘤患后术性激素水平与正常对照组水平变化不大(P>0.05)。结论:鼻咽血管纤维瘤发病机制与体内性激素水平可能存在一定程度的相关关系。 相似文献