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1.
G. V. Petrova V. A. Adarichev A. A. Krivenko G. S. Dymshits A. L. Markel' G. S. Yakobson 《Bulletin of experimental biology and medicine》1997,124(2):773-775
Sensitivity of normotensive Wistar rats and NISAG rats (with hereditary arterial hypertension) to heat stress is compared
at the organism and cell levels. High temperature sensitivity of NISAG rats correlates with a low content of the main heat
shock protein HSP70. This relationship can serve as a biochemical marker of predisposition to arterial hypertension.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 171–173, August, 1997 相似文献
2.
目的观察Agilent 2100 Bioanalyzer 芯片分析系统(以下简称Bioanalyzer)在基因差异表达研究中的应用。方法应用限制性显示技术分别从正常和热休克处理后的酿酒酵母细胞中分离出cDNA片段,然后再用Bioanalyzer和传统的琼脂糖凝胶电泳技术对RD-PCR产物进行检测分析。结果Bioanalyzer能更快速、敏感地分离和显示差异表达的基因片段,并且通过对差异片段进行定量比较,发现了数个表达有明显差异的基因片段。结论Bioanalyzer在基因差异表达研究中具有重要的应用价值。 相似文献
3.
目的:建立一种简单、稳定、可靠的PON1基因多态性分析法。方法:取外周静脉血100μl,用ROSE法提取基因组DNA,用两对引物:P192F 5′-TAT TGT TGC TGT GGG ACC TGA G-3′,P192R 5′-CAC GCT AAA CCC AAA TAC ATC TC-3′;P55F 5′-GAA GAG TGA TGT ATA GCC CCA G-3′,P55R 5′-TTT AAT CCA GAG CTA ATG AAA GCC-3分别进行PCR扩增,用限制性内切酶AlwI,NlaⅢ对两种PCR产物分别进行酶切,3%琼脂糖凝胶电泳。结果:扩增的两个PCR产物在192、55多态性位点大小分别为99bp、170bp。Alw I酶切后,凝胶电脉得到完全酶切(66bp,33bp),部分酶切(99bp、66bp、33bp),未被酶切(99bp)三种类型DNA片段(RR,QR,QQ基因型);NlaⅢ酶切后,凝胶电脉得到部分酶切(170bp,126bp,44bp),未被酶切(170bp)两种类型DNA片段(LM,LL基因型)。经双盲重复检测,结果一致。应用此方法对胃癌患者血样标本检测,发现其PON1基因多态性在192位点频率较高。结论:采用一步PCR-RFLP技术可以建立简单、稳定、可靠的PON1基因多态性分析法。 相似文献
4.
Restriction maps of the rDNA cistron of twelve species of mosquitoes in six genera of the subfamily Culicinae were constructed using eight 6 bp recognition restriction enzymes. Anopheles albimanus was used as an outgroup. The size of the rDNA cistron ranged from 8.5 kb in Aedes katherinensis to 12.9 kb in Ae. polynesiensis. A total of twenty-six sites were scored; eighteen were polymorphic among ingroup taxa. The proportion of polymorphic nucleotide sites (Pnuc) was 0.059 and the heterozygosity per nucleotide site (Hnuc) was 0.028. Wagner and Fitch Parsimony, Dollo Parsimony and Nei-Li distance/neighbour-joining methods were used to construct phylogenetic trees. The rDNA RFLP dataset did not provide a well-supported phylogeny among culicine taxa. The RFLP phylogenies are incongruent with the morphology character based and molecular phylogenies and derived relationships did not correspond with current taxonomic classifications. The lack of resolution was due to homoplasy arising from frequent independent loss or gain of restriction sites among unrelated taxa. 相似文献
5.
Donna M. Ballantine Shelley A. Klemm Terry J. Tunny Michael Stowasser Richard D. Gordon 《Clinical and experimental pharmacology & physiology》1994,21(3):215-218
1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension. 相似文献
6.
目的:研究中国汉族群体中α艾杜糖苷酶基因D4S111位点的遗传多态性。方法:采用扩增片段长度多态性(AmpFLP)分析技术,检测了广州地区汉族无血缘关系健康个体97名。结果:D4S111位点,在97名无关个体中发现5个等位基因和9种基因型,等位基因片段长度为830~510bp,基因频率为00052~03608,PIC为05966,杂合性为078。结论:中国汉族群体中D4S111位点具有高度多态性,并与其它种族间存在差异性。 相似文献
7.
Zhong Q. Wang Audrey D. Bell-Farrow William Sonntag William T. Cefalu 《Experimental gerontology》1997,32(6):E966-684
We report on the effect of age and chronic caloric restriction (CR) on insulin binding and glucose transporter content in both diaphragm and heart muscle membrane of young (11 months), mid-age (17 months), and old (29 month) ad libitum fed and CR Brown-Norway rats. The control animals received rat chow ad lib and CR animals were allowed 60% of ad libitum food. The CR regimen was initiated at four months of age and the animals were maintained on their respective diets until necropsy. There was no effect of age on insulin binding for either ad libitum or CR animals at each age evaluated. Caloric restriction significantly lowered insulin levels at each age studied when compared to the ad libitum-fed rats. However, CR animals were noted to have increased insulin binding (p < 0.001) compared to ad libitum-fed animals at each age for diaphragm muscle. For the heart, there appeared to be a decreased binding, particularly at higher insulin concentrations, in CR-fed animals. There was no net change in Glut-1 or Glut-4 levels for heart muscle membrane, or Glut-4 levels for diaphragm muscle membrane between ad libitum or CR animals. This data indicates that caloric restriction may have tissue-specific effects for insulin receptor binding, and that the improved insulin sensitivity in CR states is not a result of altered glucose transporter protein content. 相似文献
8.
S. Leskinen-Kallio 《Clinical physiology and functional imaging》1994,14(3):329-335
Summary. The particular advantages of positron emission tomography (PET) technique are that it has higher sensitivity, higher resolution, and a higher quality of image than that found in conventional nuclear medicine. The possibility of quantification and the wide range of useful tracers have raised expectations of this new method. To date, most of the human PET cancer studies have been performed with [18F]fluorodeoxyglucose (FDG) or [11CJmethionine. These are good imaging agents for tumours. However, more specific radiopharmaceuticals are required if other features of tumour metabolism are to be observed, f11Thymidine may prove to be a good tracer for quantitative measurements of tumour proliferation and [18F]misonidazole has been suggested for imaging of hypoxia. 相似文献
9.
正常人及胃癌患者胃蛋白酶原C基因多态性研究 总被引:2,自引:0,他引:2
以PGC301为探讨,对10例胃癌组织及11例正常人体组织基因组DNA中胃蛋白酶原C基因的EcoR I限制性片段长度多态性作了观察分析。发现在正常人体有三种常见等位片段,分别为20kb、5.7kb及3.6kb;一种稀有片段,3.5kb。在胃癌患者,未发现与正常人体不同的等位片段。但是,稀有片段及稀有杂交带型的出现频率高于正常组。这一结果对深入探讨胃蛋白酶原C基因稀有片段及稀有杂交带型对胃癌的诊断价 相似文献
10.
GEORGE STAVROPOULOS KOSTAS KARAGIANNIS PAUL CORDOPATIS DAVID HALLE CHAIM GILON GIORA BAR-AKIVA ZVI SELINGER MICHAEL CHOREV 《Chemical biology & drug design》1991,37(3):180-184
The analogues [Glu(OBzl)11]SP6–11 and [Glu(OBzl)11]SP5–11 of the C-terminal hexapeptide and heptapeptide of Substance P have been synthesized by conventional solution methods. In each analogue the SCH3 group of Met11 is replaced by the COOCH2C6H5 group. The in vitro activity of both analogues has been determined on three biological preparations: guinea pig ileum (GPI), rat vas deferens (RVD), and rat portal vein (RPV). The selectivity for the different receptors has been studied by utilizing atropine-treated guinea pig ileum (GPI + At). The results showed that both analogues are mainly active on GPI through the NK-1 receptor and that both analogues are equipotent to Substance P. 相似文献