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141.
文章克隆得到家蚕(Bombyx mori)神经肽促咽侧体素受体基因(Allatotropin receptor,BommoATR),开放阅读框全长为1 254 bp,编码416个氨基酸.Bommo-ATR氨基酸序列的二级结构预测为7次穿膜蛋白,符合GPCR家族成员的典型特征.实时荧光定量PCR结果表明,家蚕脑-咽下神经节复合体中的ATR mRNA在5龄幼虫期表达量最高,其次为蛹后期,蛹前期和成虫阶段表达量最低.其中5龄幼虫第2天表达量最高,1~5 d持续维持较高的表达水平,这可能与保幼激素的合成有关.  相似文献   
142.
目的探讨高脂饮食对法尼醇受体(farnesoid X receptor,FXR)敲除小鼠糖脂代谢及肝脏脂肪变性的影响。方法正常饮食(normal diet,ND)组:C57BL/6(wild type,WT)小鼠(n=6)和FXR -/- 小鼠(n=6)给予辐照灭菌维持饲料喂养12周。高脂饮食(high fat diet,HFD)组:C57BL/6小鼠(n=6)和FXR -/- 小鼠(n=6)给予45%高脂饲料喂养12周。小鼠处死后全自动生化分析仪检测血清总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、高密度脂蛋白胆固醇(High density lipoprotein cholesterol,HDL-C)、谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate aminotransferase,AST)和总胆汁酸(total bile acid,TBA)指标; RT-PCR检测肝脏炎症因子TNF-α、TLR4和FXR下游基因小分子异源二聚体(small heterodimer partner,SHP)、胆固醇7α-羟化酶(cholesterol 7α-hydroxylase,CYP7A1)的相对表达量; HE染色观察肝脏脂肪变性情况。结果高脂饮食喂养条件下,C57BL/6小鼠和FXR -/- 小鼠体质量变化无差异,但相比C57BL/6小鼠,FXR -/- 小鼠表现出更为严重糖耐量受损(P <0. 01)、脂质代谢紊乱(P <0. 01)、血清胆汁酸增高(P <0. 01)、肝脏炎症(P <0. 01)和肝脏脂肪变性。结论 FXR的缺失引起小鼠糖脂代谢紊乱、胆汁酸代谢异常、肝脏脂肪变性,但这种改变需要高脂饮食的诱导。  相似文献   
143.
We report that receptors for vitamin D exist in distinct regions of the heart in female and male mice, predominantly in the right atrium where most of the cardial atrial natriuretic peptide (ANF) is produced. Tritiated 1,25-dihydroxyvitamin D3 (1,25-D3, vitamin D, soltriol) and ANF are colocalized in nuclei and cytoplasm respectively in identical cardiomyocytes. Changes of ANF tissue and blood levels under dietary deficiency and treatment with 1,25-D3 suggest direct genomic actions of vitamin D on myoendocrine cells of the atrium for the regulation of ANF manufacture and secretion. These results were obtained by combining thaw-mount autoradiography with immunocytochemistry using tritiated 1,25-D3 and an antibody against rat ANF. This antibody was also used in a radioimmunoassay to determine atrial natriuretic factor in plasma, atria and ventricles of normal or vitamin D-deficient mice.  相似文献   
144.
145.
Summary Small intestinal explants from pre- and post-natal rats were incubated in an organ culture system in the absence and presence of epidermal growth factor (EGF). The rate of synthesis of small intestinal DNA and protein as well as the activity of lactase and alkaline phosphatase increased rapidly between 17 and 20-day gestational age, whereafter they declined. The maximal incorporation of3H-thymidine and14C-alanine into DNA and protein, respectively, was significantly stimulated by EGF (100 ng/ml). EGF had no effect on the activity of either lactase or alkaline phosphatase in the small intestinal explants.Acknowledgment. The project was supported by grants from the Veterans Administration Research Service. The authors wish to thank Dr. M. C. Geokas, Chief, Department of Medicine, Veterans Administration Medical Center, Martinez, CA, for providing us with excellent laboratory facilities and for his encouragement in this study.  相似文献   
146.
应用^125I-CKL对正常人和不育患者精子膜上凝集素受体进行研究的结果表明,不育精子膜上凝集素受体的差异,可能是不育的原因之一。  相似文献   
147.
Summary This is a selective review of recent trends in research on the cellular receptor for the alpha-beta interferons. It deals mainly with work published in the last three years (1985–88), and therefore mainly with receptors for the human interferons. The binding characteristics of several human alpha interferons are examined, and the importance of in vitro experimental models for establishing the relationship between receptor binding and the cellular response is emphasized.  相似文献   
148.
Summary The platelet membrane insulin receptors of healthy and non-insulin dependent (type 2) diabetic patients were studied. Receptor number and affinity proved to be decreased in type 2 diabetes mellitus. The changes in platelet insulin receptor characteristics are in good correlation with the alterations reported in other tissues or cells. The possible role of these phenomena in the pathogenesis of disturbed platelet function in diabetics needs further investigation.  相似文献   
149.
Effects of anti-EGF serum on newborn mice   总被引:2,自引:0,他引:2  
Summary Administration of anti-EGF serum to newborn mice led to delay of eyelid opening and incisor tooth eruption, acceleration of hair growth and delay of weight gain. These results indicate that in the first week after birth EGF still has a physiological function, which can be abrogated by anti-EGF serum.  相似文献   
150.
Summary On each day of the estrous cycle hCG binding to follicle increased from 09.00 to 21.00 h; then hCG binding was static until 09.00 h of the next day. FSH binding did not exhibit rhythmicity. This pattern of hCG binding may be related to the pulsing of LH on each cycle day.Acknowledgments. This work was supported by grants from NICHD (15 526, KO478) to P.F.T. and Center grant to the Kansas Center of Mental Retardation and Human Development (HD 02528). A. K. was supported in part by the Council for International Exchange of Scholars (Fulbright Foundation).  相似文献   
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