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51.
目的:在大肠杆菌中表达人B组轮状病毒WH-2株VP7蛋白并制备其兔抗血清。方法:根据B组轮状病毒(GBRV)WH-2株vp7基因的全序列设计引物,用PCR的方法扩增得到vp7基因的编码区。将其克隆到原核GST融合表达载体pGEX-KG内,转化大肠杆菌E.coliDH5α,IPTG诱导表达人B组轮状病毒WH-2株VP7蛋白,经SDS-PAGE分离纯化表达的蛋白免疫新西兰兔,制备人B组轮状病毒WH-2株VP7蛋白抗血清。结果:经鉴定确认,vp7基因以正确的方式插入到载体中,此重组表达载体经IPTG诱导后,可表达相对分子量为53.4 kDa的GST-VP7融合蛋白。制备的抗血清经同样诱导表达的表达载体pGEX-KG表达产物吸收后1:500倍稀释后用Western Blot分析,与53.4 kDa的GST-VP7融合蛋白获得特异性显色信号。结论:人B组轮状病毒WH-2株VP7蛋白成功在大肠杆菌中GST融合表达,所表达的蛋白和制备的抗体不但为研究结构与功能提供了物质基础,也为GBRV所引起的疾病预防、诊断和治疗等流行病学研究和临床诊断奠定了基础,具有重要实际应用价值。 相似文献
52.
C Y Chai A M Lin C K Su S R Hu C Yuan L S Kao J S Kuo D S Goldstein 《Journal of the autonomic nervous system》1991,33(1):35-46
Effects of stimulation of brainstem sites on hemodynamics and plasma catecholamine levels were assessed in cats under chloralose-urethane anesthesia. Pressor areas of the dorsal medulla (DM) and ventrolateral medulla (VLM) and the depressor area of the paramedian reticular nucleus (PRN) were stimulated electrically using a monopolar electrode, or chemically using sodium glutamate microinjection. Plasma levels of norepinephrine (NE) and epinephrine (EPI) were measured in caval blood above the adrenal veins. Electrical stimulation of the DM and VLM produced increases in blood pressure and in plasma NE and EPI levels that were enhanced after acute vagotomies. The NE and EPI responses were attenuated after acute, bilateral adrenalectomies, confirming augmented adrenomedullary secretion, whereas the pressor responses were intact. Injection of sodium glutamate into the same pressor regions of the DM or VLM also produced pressor responses and elevated plasma catecholamine levels, indicating that the responses resulted from activation of neuronal perikarya. Stimulation of the PRN attenuated pressor and catecholamine responses during stimulation of the DM and VLM. The results indicate that pressor responses during stimulation of the DM and VLM are due at least partly to activation of perikarya in these regions, are associated with but not dependent on adrenomedullary activation, and are enhanced after vagotomy; and that neurons of the PRN exert inhibitory modulation of the pressor and adrenomedullary responses during stimulation of VLM and DM. 相似文献
53.
A slow-moving gamma chain variant was discovered in the cord blood of an infant born to parents of the Han nationality from Jiangsu. The variant, which migrated electrophoretically at alkaline pH between Hb A and Hb D, was characterized by an Asp----His substitution at gamma 73, while residues gamma 75 and gamma 136 were occupied by Ile and Ala, respectively. As the A gamma T-chain was also present, this baby has two types of abnormal gamma-chain. The variant was named Hb F-Xin-Su. 相似文献
54.
55.
F Nakhoul L H Kayne N Brautbar M S Hu A McDonough P Eggena M S Golub M Berger C T Chang N Jamgotchian 《Toxicology and industrial health》1992,8(1-2):89-102
Chronic lead exposure may cause hypertension in normotensive rats. This hypertensinogenic effect has been attributed to perturbations in the renin-angiotensin axis, the contractile response of the vascular smooth muscle, or the intracellular Ca2+ homeostasis as a consequence of the inhibition of Na(+)-K(+)-ATPase activity. In this study we examined the short-term effect of lead exposure on blood pressure, plasma renin activity, vascular contractility, and renal Na(+)-K(+)-ATPase activity and abundance in the spontaneously hypertensive rat. Our data indicate that modest lead exposure caused blood pressure elevation within two weeks in this rat strain that is genetically susceptible to the development of hypertension. This rapid blood pressure-elevating effect did not appear to depend on the mechanisms described in hypertension associated with more chronic lead exposure listed above. This acute model provides an additional approach to the study of lead-induced hypertension. 相似文献
56.
为探索天然超氧化物岐化酶(SOD)岐化超氧离子的机理,及用于临床的可能性,我们合成了乳酸、柠檬酸和酒石酸的锰(Ⅱ)配合物作为Mn-SOD的模拟物,用光照法测定了它们的活性,得到了有意义的结果:锰配合物作为Mn-SOD的模拟物,有肯定的活性,其中以乳酸锰配合物活性最高。 相似文献
57.
P C Hu 《中华结核和呼吸杂志》1992,15(3):163-4, 191-2
In our study, we observed that (1) High RCIA were discovered in these two groups. (2) In the group of pulmonary tuberculosis, the C3b receptor activities remained no change after antituberculous therapy, but the amounts of immune complexes bearing on RBC decreased. In the patients with the high RCIA, CIC was discharged rapidly and the lesions of tissue produced by CIC were prevented. In the patients with silicotuberculosis, both silica and tuberculous bacilli may act as immune adjuvant and enhance the hypersensitivity. So the C3b receptor activities were higher in silicotuberculosis patients. 相似文献
58.
“软骨康”对损伤关节软骨修复机制的初探 总被引:3,自引:0,他引:3
我们用中药软骨康,对全层缺损的兔膝关节股骨髁关节软骨,进行三周治疗,取得较为满意的效果。实验结果表明,软骨康在促进成纤维细胞分泌大量胶原纤维,促进组织再生;对血管增生和扩张血管加速局部血循环以及提高滑膜的增生和活性,使其参与损伤组织的再建,均有独到作用。 相似文献
59.
四种可溶性载体对骨形态发生蛋白在小鼠体内诱导成骨活性的影响 总被引:28,自引:0,他引:28
以四种可溶性物质作为牛骨形态发生蛋白(bBMP)的载体,通过实验观察哪种物质是bBMP的有效缓释载体。将聚乙烯吡咯烷酮(PVP)、葡聚糖、羟乙基淀粉(HES)、甘露醇分别与等量bBMP复合后,注射入小鼠股部肌肉,观察组织学成骨及测定标本内钙含量。结果,bBMP/PVP有良好成骨,吸收较快,未见炎症及排斥反应,其混悬液较稳定,具有良好的适针性及可注射性,bBMP/甘露醇只有很低成骨率。其余各组未见成骨。PVP对bBMP具有满意助溶、助悬及缓释载体作用,对bBMP活性无损害,生物相容性好。 相似文献
60.
5例强直性肌营养不良患者的腓肠肌活检标本超微结构研究结果发现,除肌纤维变性、萎缩和结缔组织增生外,毛细血管病变特别突出。血管壁严重增厚,基板呈多层性改变,周细胞增生。有些复层的毛细血管基板多达9层。内皮细胞外可有多层周细胞半包绕血管,有些周细胞又发出分支沿管壁延伸。周细胞一般位于内皮细胞下第一层基板之外,也可位于复层基板之中,周细胞与周细胞之间有多层基板。内皮细胞和周细胞内富含吞饮小泡。血管病变程度与肌纤维变性程度呈平行关系。 相似文献