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In some pathophysiological processes such as severe shock, the patients and animal experimental models fail to respond to pressor medicine. Vascular hyporesponse or vasodilation is one of the key problems in treatment of these patents. Although considerable progress had been made in recent years, the precise mechanisms of vascular contractile hyporeactivity have not been completely elucidated. A number of studies indicate that vascular hyporesponse or vasodilation correlate with many factors. In this review, the possible mechanisms about vascular hyporesponse or vasodilation during shock and other pathphysiolgoical processes were discussed. 相似文献
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AIM:To investigate the effects of FK506 on anti-glomerular basement membrane(GBM) nephritis in rats. METHODS: Anti-GBM nephritis model was elaborated by rabbit anti-rat GBM antibody injection in SD rats in this study. The rats were divided into three groups: FK506 treated group(0.5 mg·kg-1·d-1, sc), untreated nephritis control group and normal control group. FK506 was administered daily six hours after injection of anti-GBM IgG. All the rats were observed urinary protein at the 4th day, the 14th day and the 21st day. At the same time, the kidney specimens were collected, and T cell transforming function was also monitored.RESULTS:Rats injected with rabbit anti-GBM Ab developed heavy proteinuria by 4 days, and serum creatinine and serum urea appeared which kept on the rising. Glmerular hypercellularity, crescents, and protein casts were observed in nephritic rats. By electron microscopy, the thickening of GBM and loss of foot processes were seen. T cell transforming function was higher than normal. But, all pathological changes obviously turned for the better in FK506 treated group. CONCLUSION:FK506 could inhibit the progression of rat anti-GBM nephritis. 相似文献
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利用远缘杂交创造核果类果树新种质的研究 总被引:5,自引:0,他引:5
以桃、杏、李、樱桃、杏梅等果树的 1 4个品种为亲本 ,3年来共进行了 80余个组合的远缘杂交试验 ,探讨了核果类果树远缘杂交的亲和性 ,并对远缘杂种幼胚进行了胚抢救。结果表明 ,铃铛花期授粉的坐果率显著高于初花期授粉 ;同一杂交组合 ,正反交坐果率差异显著 ,母本对远缘杂交亲和性影响很大 ,选择自交亲和或自然坐果率高的种或品种做母本容易克服远缘杂交的不亲和性 ;适宜场强的静电场、He -Ne激光处理及60 Coγ射线与He -Ne激光联合处理花粉 ,均能显著提高花粉离体萌芽率 ,用上述处理的花粉进行的远缘杂交坐果率也明显高于对照 ;60 Coγ射线单独处理则降低了花粉离体萌芽率 ,远缘杂交的坐果率也低于对照 ;对远缘杂种幼胚及时地进行胚抢救 ,并诱导形成多丛芽 ,是克服核果类果树远缘杂种不育性的有效方法。研究并筛选出了李、樱桃胚萌发与生长、多丛芽诱导与增殖以及生根培养等最佳培养基配方。目前已将欧洲甜樱桃×中国樱桃、大石早生李×泰安巴旦水杏及凯特杏×总统李等一批核果类果树远缘杂种定植于露地 ,其中欧洲甜樱桃与中国樱桃的种间杂种是国内外首次获得 相似文献
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The present study examines the contribution of the nucleus to meiotic competence in mouse oocytes that were reconstructed using nuclear transfer. Three types of reconstructed oocytes were produced: MP‐GV, by transplanting the male pronucleus (MP) into germinal vesicle (GV) stage oocytes; 3T3‐GV, by transplanting the nucleus of a National Institute of Health (NIH) 3T3 cell into a GV stage oocyte; and 3T3‐MII, by transplanting the nucleus of an NIH 3T3 cell into a metaphase II (MII) stage oocyte. The fusion rates differed, but not significantly, in the MP‐GV, 3T3‐GV, and 3T3‐MII groups (77, 63, 56%, respectively). Then, meiotic competence was compared in MP‐GV, 3T3‐GV and non‐manipulated GV stage oocytes as a control. Nuclear envelope breakdown occurred in all the reconstructed oocytes, as well as the control ones. The percentage of first polar body extrusion differed between the MP‐GV (100%), 3T3‐GV (72%), and control (67%) groups. DNA staining with Hoechst 33342 revealed that in the MP‐GV‐group oocytes that had reached MII stage, the chromosomes were condensed and aligned in a regular array similar to the normal metaphase plate. By contrast, in 3T3‐GV group oocytes, the condensed chromosomes were irregularly scattered in the cytoplasm. These results suggest that the donor nucleus affects meiotic competence in reconstructed oocytes. 相似文献
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以猪胸膜肺炎放线杆菌血清7型25-4株基因组DNA为模板,PCR方法扩增外膜蛋白(OMP)5′末端保守区基因片段(OMPc),酶切及核苷酸序列分析鉴定后,与原核表达载体质粒pGEX-6P-1进行连接,构建成重组表达载体pGEX-OM-Pc,转入大肠杆菌BL21中,以IPTG进行诱导,SDS-PAGE电泳分析发现,转化了重组质粒的菌株所表达的融合蛋白相对分子量为34 kD,与实际预测相符,命名为GST-OMPc.GST亲和层析柱进行纯化,ELISA方法对纯化蛋白进行检测.结果表明:纯化蛋白GST-OMPc能够与兔抗猪胸膜肺炎放线杆菌血清7型的阳性血清反应.OMPc蛋白的成功表达为其功能的研究打下基础. 相似文献
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