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目的:原核表达人类肥胖基因瘦素蛋白,方法:以携人类肥胖基因的pUC119-ob为模拟,PCR扩增瘦素蛋白基因片段,并克隆到pET-32a构建重组表达质粒pET-32a-ob,经酶切和测序鉴定后,转化至大肠埃希菌DH5α中表达,SDS-PAGE电泳鉴定表达产物。结果:测序和限制性分析均证明了pET-32a-ob的序列正确,转化的DH5α可高效表达一个30kD融合蛋白,与预期结果一致。结论:经pET-32a-ob转化的DH5α可有效表达重组人类瘦素蛋白,为进一步研究瘦素蛋白的生物活性提供了基础。 相似文献
85.
目的:比较急性心肌梗死介入治疗中冠脉内常规给予以及必要时给予血小板膜糖蛋白(GP)Ⅱb/Ⅲa受体拮抗剂替罗非班两种给药方式对冠脉血流异常的影响,寻找较好的替罗非班用药方式。方法:入选九四医院2005年1月至2008年10月急性心肌梗死直接PCI患者58例,随机分成常规给药组(血管开通前所有患者冠状动脉内均注射替罗非班,n=30)与必要时给药组(血管开通后即时造影显示TIMI血流≤2级者冠脉内注射替罗非班,TIMI血流3级者不给药,n=28),观察支架植入后30分钟TIMI血流、30天内主要不良心血管事件(MACE)、出血以及血小板减少情况。结果:必要给药组冠脉内给药可显著改善冠脉血流(TIMI3级给药前46.4%,给药后75%,P〈0.05),常规给药组支架植入后30分钟TIMI3级获得率高于必要给药组(96.7%比75%,P〈0.05),MACE、出血和血小板减少事件两组之间差异无统计学意义。结论:冠脉内给予替罗非班可有效降低急性心肌梗死PCI术中血流异常情况,血管开通前冠脉内常规给药方式优于必要时给药方式。 相似文献
86.
HaiYan Shan Siyang Zhang Xuelian Li Kai yu Xin Zhao Xinyue Chen Bo Jin XiaoJuan Bai 《Journal of cellular and molecular medicine》2014,18(6):1071-1080
Angiotensin II (Ang II) plays important roles in ageing‐related disorders through its type 1 receptor (AT1R). However, the role and underlying mechanisms of AT1R in ageing‐related vascular degeneration are not well understood. In this study, 40 ageing rats were randomly divided into two groups: ageing group which received no treatment (ageing control), and valsartan group which took valsartan (selective AT1R blocker) daily for 6 months. 20 young rats were used as adult control. The aorta structure were analysed by histological staining and electron microscopy. Bcl‐2/Bax expression in aorta was analysed by immunohistochemical staining, RT‐PCR and Western blotting. The expressions of AT1R, AT2R and mitogen‐activated protein kinases (MAPKs) were detected. Significant structural degeneration of aorta in the ageing rats was observed, and the degeneration was remarkably ameliorated by long‐term administration of valsartan. With ageing, the expression of AT1R was elevated, the ratio of Bcl‐2/Bax was decreased and meanwhile, an important subgroup of MAPKs, extracellular signal‐regulated kinase (ERK) activity was elevated. However, these changes in ageing rats could be reversed to some extent by valsartan. In vitro experiments observed consistent results as in vivo study. Furthermore, ERK inhibitor could also acquire partial effects as valsartan without affecting AT1R expression. The results indicated that AT1R involved in the ageing‐related degeneration of aorta and AT1R‐mediated ERK activity was an important mechanism underlying the process. 相似文献
87.
Association of SLC22A4 Gene Polymorphism with Rheumatoid Arthritis in the Chinese Population 下载免费PDF全文
Tian‐li Ren Zhi‐jun Han Cheng‐jian Yang Yuan‐xing Hang De‐yu Fang Ke Wang Xue Zhu Xiao‐jing Ji Fan‐fan Zhou 《Journal of biochemical and molecular toxicology》2014,28(5):206-210
Rheumatoid arthritis (RA) is a chronic inflammatory disease with complex genetic factors. Single‐nucleotide polymorphisms (SNPs) in the SLC22A4 gene have been previously reported to be associated with RA in Japanese but not European populations. This study further investigated the association of SLC22A4 polymorphisms, in particular slc2F1/slc2F2, with RA in the Chinese population, the largest Asian population. A total of 160 human subjects with 95 RA patients and 65 healthy controls were genotyped for slc2F1‐G/A and slc2F2‐C/T polymorphisms. The results showed that there was a significant difference in the genotype distribution of these two polymorphisms between the two groups. In addition, the presence of slc2F1 A allele and slc2F2 T allele carries a 1.93‐fold and 2.14‐fold increased risk for anticyclic citrullinated peptide (CCP) positivity, respectively. Overall, this study provided evidence that SLC22A4 gene polymorphisms played important roles in the etiology of RA in the largest Asian population, the Chinese population. 相似文献
88.
用就Q-Sepharose Fast Flow对Vero细胞基质制备的I型口服脊髓灰质炎减毒活疫苗悬液进行纯化。病毒液经滤过澄清和超浓缩,获得85%的病毒感染性滴度回收率,而经Q-Sepharose F.F.纯化的病毒悬液,病毒感染性滴度回收率达100%。纯化后的病毒液用α-^32PdATP标记DNA探针膜杂交法测定,宿主Vero细胞基质DNA残余含量远低于100pg/剂量的标准;rct/40特征 相似文献
89.
苦瓜冻干粉对动物的降血糖作用及急性毒性 总被引:21,自引:0,他引:21
对药食同源植物苦瓜(Momordica charantia L.)的鲜汁冻干粉对动物的降血糖作用及急性毒性进行了药理实验,苦瓜冻干粉(生药量20g/kg和40g/kg)对药物性高血糖小鼠具有显著的降血糖作用,同时对正常小鼠血糖没有影响;苦瓜冻干粉的小鼠口服LD50为生药量704.8g/kg(95%可信限生药量618.4~804g/kg),其产生降糖药效的剂量仅为其LD50的1/35~1/17。 相似文献
90.
毒死蜱对家白蚁毒杀作用的时间与剂量效应 总被引:2,自引:0,他引:2
用含不同毒死蜱浓度的毒土对家白蚁(Coptoternes foumosamus Shiraki)进行了生物测定,浓度范围为0.015-0.48mg/kg。观察2周。实验观察发现土壤中毒死蜱浓度为0.48-0.06mg/kg时,白蚁接触毒土出现的死亡高峰为4小时至2天;在0.03mg/kg时,死亡高峰在1周以后;而浓度为0.015mg/kg时,2周内仍观察不到白蚁死亡。所获的生物测定数据很好地拟合时 相似文献