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61.
本研究目的在于探讨丝裂素活化蛋白激酶(MAPK)是否在AngⅡ(10-8mol/L)诱导的培养新生大鼠心肌成纤维细胞(FB)的增殖反应中起重要作用。实验以FB数目和DNA合成速率(3H-胸腺嘧啶掺入率)为增殖指标,[γ-32P]ATP掺入法和免疫印迹法分别测定FBMAPK的活性和含量,结果发现(1)AngⅡ处理FB24h后,DNA合成速率和细胞数比对照组分别增加60%和39%;(2)AngⅡ处理FB5min后,MAPK活性比对照组增高203%;(3)培养新生大鼠FB含有两个MAPK同型体-p44mapk和p42mapk,其中p44mapk含量高于p42mapk,分别为总量的58%和42%。AngⅡ处理5min后,MAPK蛋白含量(p44+p42〕增高429%,其中p44mapk的增加明显大于p42mapk的增加,分别比相应对照增高486%和349%。以上结果表明,AngⅡ诱导的MAPK活性和含量的增加,参与了FB的增殖反应,其中p44mapk的作用较为显著  相似文献   
62.
INTRoDUCTIONThichosanthin(Tk),aplantproteinisolatedfromaChinesemedicinalherbTh-1.Correspondenceaddress:Dr.KuangYenCHoU,ShanghaiInstituteofImmunology,Shang-haiSecondMedicalUniversity28oSouthChongqingRoad,Shanghai2ooo25,China.Fax:(8621)63846383,E-mail:my@sh…  相似文献   
63.
广布中剑水蚤对裸腹和秀体的摄食(英文)   总被引:2,自引:0,他引:2  
1995年6月至9月,在武汉东湖,通过摄食实验和野外调查,作者研究了广布中剑水蚤对裸腹和秀体的摄食。研究结果证实,广布中剑水蚤能够抓取和摄食裸腹和秀体。广布中剑水蚤对小型裸腹的平均摄食率高于大型裸腹。多重统计分析结果表明,广布中剑水蚤对小型和大型裸腹的摄食率有显著差异(P=00335),捕食者喜食小型猎物。由于广布中剑水蚤的摄食习性,它对裸腹和秀体的种群动态有重要影响,但随着鱼产量增加,广布中剑水蚤对猎物摄食的影响效果被减弱了。  相似文献   
64.
结合纳米技术开发新剂型药物已成为提高免疫逃逸能力和增加治疗效率低的天然化合物局部药物浓度的有效策略。青蒿素和原花青素具有良好的抗动脉粥样硬化活性,但是两者药物体内清除速度快,生物利用度低,对动脉粥样硬化的治疗有限。  相似文献   
65.
<正>背景:使用23价肺炎球菌多糖疫苗(PPV23)的好处是有争议的。作者研究了PPV23在年龄大于等于60岁人群中预防社区获得性肺炎(CAP)的临床效果。方法 :研究是在西班牙的塔拉戈纳地区,从2008年11月1日到2011年12月30日,年龄≥60岁人群中选取27 204人作为队列研究的人群基础。主要结果来自肺炎球菌CAP(有菌血症和非菌血  相似文献   
66.
Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a good agreement among the laboratories participating in the study. Since test standardization represents a key step for future application in clinical practice, further studies of the patients' samples are in progress to establish the real meaning and utility of the proviral DNA load for clinical management of HIV-1 infected patients.  相似文献   
67.
The Assessment of Lescol in Renal Transplantation clinical trial demonstrated the efficacy of fluvastatin in reducing cardiovascular (CV) disease in renal transplant recipients. The study included a voluntary pharmacogenetic component, enrolling 1,404 patients, which allowed association testing of baseline measures and longitudinal analysis of the 707 fluvastatin-treated and 697 placebo-treated individuals. A candidate gene approach, examining 42 polymorphisms in 18 genes, was used to test for association between selected polymorphisms and major adverse cardiac events, graft failure, change in LDL and HDL cholesterol, and baseline LDL and HDL cholesterol. Reported associations between cholesteryl ester transfer protein (CETP) and baseline HDL cholesterol were replicated, with four previously implicated single nucleotide polymorphisms significantly associated in males and one in females; tests of reported associations between CETP and CV disease yielded varying results. We found no evidence for genetic factors affecting fluvastatin response. Polymorphisms in 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) previously reported to affect the efficacy of pravastatin did not show a similar effect on the reduction of LDL cholesterol by fluvastatin.  相似文献   
68.
Circulating levels of inflammatory markers can predict cardiovascular disease risk. To identify genes influencing the levels of these markers, we genotyped 1,343 single-nucleotide polymorphisms (SNPs) in 1,184 African Americans from the Health, Aging and Body Composition (Health ABC) Study. Using admixture mapping, we found a significant association of interleukin 6 soluble receptor (IL-6 SR) with European ancestry on chromosome 1 (LOD 4.59), in a region that includes the gene for this receptor (IL-6R). Genotyping 19 SNPs showed that the effect is largely explained by an allele at 4% frequency in West Africans and at 35% frequency in European Americans, first described as associated with IL-6 SR in a Japanese cohort. We replicate this association (P<1.0x10-12) and also demonstrate a new association with circulating levels of a different molecule, IL-6 (P<3.4x10-5). After replication in 1,674 European Americans from Health ABC, the combined result is even more significant: P<1.0x10-12 for IL-6 SR, and P<2.0x10-9 for IL-6. These results also serve as an important proof of principle, showing that admixture mapping can not only coarsely localize but can also fine map a phenotypically important variant.  相似文献   
69.
The genome of a new SV40 strain (SV-IMB) isolated from a rhesus monkey was completely sequenced and compared with other isolates. The results showed that the whole genome contains 5246bp, and the average identity of SV-IMB was 98.1% as compared to other SV40 isolates. Its regulatory region is composed of a complete enhancer and a defective enhancer. Amino acid changes occurred to some extent in both the large T antigen (T-Ag) and VP1 region. The findings demonstrate that the SV-IMB is a new SV40 isolate.  相似文献   
70.
Insect viruses are attractive as biological control agents and could be a feasible alternative to chemical insecticides in the management of insect infestations. This review describes recent advances in the development of wild-type and genetically modified viruses as insecticides. A new strategy of application of insect viruses in China is reviewed. Also, the assessment of biosafety of genetically modified Helicoverpa armigera Nucleopolyhedovirus (HearNPV) is emphasized as a case-study.  相似文献   
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