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91.
Summary A male patient with an interstitial deletion 13q14q31 is described. Our necropsy findings included a left retinoblastoma and several gross internal malformations. In this paper we reaffirm that band 13q14 is involved in cases of retinoblastoma and we propose, after studying accompanying cases of total or partial long arm trisomies 13, that the loss of specific 13q bands, from 13q14 to 13q31 is responsible for the congenital defects we are describing.  相似文献   
92.
人心肌肌球蛋白轻链1的克隆,表达纯化和单抗制备   总被引:4,自引:2,他引:2  
报道了中国人心肌肌球蛋白轻链1cDNA的核苷酸序列,并由此推算的氨基酸序列。与国外发表的人心肌肌球蛋白轻链的氨基酸序列比较,发现有两处差异,即在24位,由谷氨酸变为丙氨酸,则从98位起至101位有4个氨基酸序列的连续差异,即由天冬酰胺-精氨酸-丝氨酸-赖氨酸变为赖氨酸-脯氨酸-精氨酸-谷氨酰妥,推测可能是由于人种差异而引起的。利用该cDNA在大肠杆菌内的表达产物,已获得一株高效的抗中国人心肌肌球蛋  相似文献   
93.
糖脂修饰的脂肪酶在有机溶剂中催化酯化反应   总被引:8,自引:0,他引:8  
本文研究了不同糖脂化合物修饰的脂肪酶在有机溶剂中催化长碳链脂肪酸和脂肪醇的酯化反应,不同的脂肪酶经糖脂修饰后,催化活性均有不同程度的提高。在4种糖脂和6种脂肪酶中,以蔗糖酯SE-7修饰脂肪酶CES活性最高,本文还对pH、溶剂和温度等对修饰脂肪酶生的影响进行了研究。  相似文献   
94.
范祖森  敖世洲 《生命科学》1999,11(5):193-196
p27基因位于人类染色体12p13,其编码的蛋白对cyclinsCDKs具有广泛的抑制活性,是细胞周期调控的抑制蛋白。它以化学剂量的方式调节细胞周期的进程,参与细胞的生长、分化等过程。对p27基因的发现、基因结构、对细胞周期和细胞分化的调控机制以及与肿瘤的关系作一介绍。  相似文献   
95.
Analysis by two-dimensional gel electrophoresis revealed that Mycobacterium avium expresses several proteins unique to an intracellular infection. One abundant protein with an apparent molecular mass of 50 kDa was isolated, and the N-terminal sequence was determined. It matches a sequence in the M. tuberculosis database (Sanger) with similarity to the enzyme isocitrate lyase of both Corynebacterium glutamicum and Rhodococcus fascians. Only marginal similarity was observed between this open reading frame (ORF) (termed icl) and a second distinct ORF (named aceA) which exhibits a low similarity to other isocitrate lyases. Both ORFs can be found as distinct genes in the various mycobacterial databases recently published. Isocitrate lyase is a key enzyme in the glyoxylate cycle and is essential as an anapleurotic enzyme for growth on acetate and certain fatty acids as carbon source. In this study we express and purify Icl, as well as AceA proteins, and show that both exhibit isocitrate lyase activity. Various known inhibitors for isocitrate lyase were effective. Furthermore, we present evidence that in both M. avium and M. tuberculosis the production and activity of the isocitrate lyase is enhanced under minimal growth conditions when supplemented with acetate or palmitate.  相似文献   
96.
Y Zu  M Kohno  I Kubota  E Nishida  M Hanaoka  Y Namba 《Biochemistry》1990,29(4):1055-1062
We have characterized the cellular proteins which are rapidly phosphorylated by interleukin 2 (IL 2) in a human IL 2 dependent cell line. When treated with IL 2, the phosphorylation of five proteins, 65, 50, 37, 24, and 21 kDa, was found in IL 2 dependent cell lines by two-dimensional gel electrophoretic analysis. After cell conversion from an IL 2 dependent state to an IL 2 independent state, one of the five phosphoproteins, the 65-kDa protein, became constitutively phosphorylated even without addition of IL 2. Also, in other IL 2 independent cell lines, such as KUT-2 and HUT-102, constitutive phosphorylation of the 65-kDa protein occurred without IL 2-stimulation. So our researchers were focused on biochemical characterization of the 65-kDa protein. It was found that the 65-kDa protein was one of the major cellular proteins by comparing the results of two-dimensional gel electrophoretic analysis of [32P]Pi-labeled and [3H]leucine-labeled cellular proteins and peptide mapping analysis. Subcellular fractionation studies indicated that the 65-kDa protein is a cytosol protein. The 65-kDa protein was purified from cytosol of a human T cell line, and its amino acid composition and amino acid sequences of its three oligopeptides were determined. It was found that the 65-kDa protein is identical with 1-plastin.  相似文献   
97.
ABSTRACT: BACKGROUND: As a known regulator of apoptosis, survivin has positive relationship with lymphatic metastasis in breast cancer. This study aims to detect the difference in expression between survivin and vascular endothelial growth factor-C (VEGF-C) in treated breast cancer cells and tissues, and to analyze the correlation among survivin, VEGF-C and lymphatic metastasis. METHODS: Plasmid with survivin and VEGF-C shRNA and lentivirus with survivin gene were constructed and transfected into breast cancer cell ZR-75-30. Then the expressions of the two genes were examined using western blot analysis and real-time PCR. The change of invasiveness of breast cancer cells was assessed using matrigel invasion assay. Using immunohistochemistry, the expression of survivin and VEGF-C were analyzed in 108 clinical breast cancer cases with breast cancer tissue and lymph node. RESULTS: Survivin regulated the expression of VEGF-C at both protein and mRNA levels in breast cancer cells. Immunohistochemical analysis showed that the level of VEGF-C expression was significantly related with that of survivin in breast cancer tissues (p<0.05). VEGF-C was found to participate in the process of breast cancer cells invasion mediated by survivin. The co-expression of the two and the single expression of any one took significant difference in positive lymph node (p<0.05). CONCLUSIONS: Survivin takes an important part in regulating the expression of VEGF-C. VEGF-C could influence the invasive ability mediated by survivin. The co-expression of survivin and VEGF-C is more statistically significant to assess lymphatic metastasis in breast cancer. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/9193530897100952.  相似文献   
98.
Although genome-wide association studies (GWAS) have identified hundreds of complex trait loci, the pathomechanisms of most remain elusive. Studying the genetics of risk factors predisposing to disease is an attractive approach to identify targets for functional studies. Intracranial aneurysms (IA) are rupture-prone pouches at cerebral artery branching sites. IA is a complex disease for which GWAS have identified five loci with strong association and a further 14 loci with suggestive association. To decipher potential underlying disease mechanisms, we tested whether there are IA loci that convey their effect through elevating blood pressure (BP), a strong risk factor of IA. We performed a meta-analysis of four population-based Finnish cohorts (n(FIN) = 11 266) not selected for IA, to assess the association of previously identified IA candidate loci (n = 19) with BP. We defined systolic BP (SBP), diastolic BP, mean arterial pressure, and pulse pressure as quantitative outcome variables. The most significant result was further tested for association in the ICBP-GWAS cohort of 200 000 individuals. We found that the suggestive IA locus at 5q23.2 in PRDM6 was significantly associated with SBP in individuals of European descent (p(FIN) = 3.01E-05, p(ICBP-GWAS) = 0.0007, p(ALL) = 8.13E-07). The risk allele of IA was associated with higher SBP. PRDM6 encodes a protein predominantly expressed in vascular smooth muscle cells. Our study connects a complex disease (IA) locus with a common risk factor for the disease (SBP). We hypothesize that common variants in PRDM6 can contribute to altered vascular wall structure, hence increasing SBP and predisposing to IA. True positive associations often fail to reach genome-wide significance in GWAS. Our findings show that analysis of traditional risk factors as intermediate phenotypes is an effective tool for deciphering hidden heritability. Further, we demonstrate that common disease loci identified in a population isolate may bear wider significance.  相似文献   
99.
目的:监测中国南极冰盖考察预选队员心血管系统随海拔增高的变化,探讨筛查低氧易感队员和急性高原病的防治。方法:用无创血流动力学监护仪和十二导联心电图机,在北京(40 m)、拉萨(3 650 m)、羊八井(4 300 m)对第25次和26次南极冰盖考察预选队员心血管功能进行连续动态性监测。结果:随着海拔的增高,心率、收缩压、舒张压、平均动脉压、外周血管阻力、外周血管阻力指数显著升高(P0.05),心输出量、心指数、搏出量、搏出指数、加速度指数、速度指数、左心射血时间显著降低(P0.05),预射血期呈降低趋势(P0.05)。结论:随着海拔的增高,预选队员的外周血管阻力显著升高,左心泵血和收缩功能减弱且与Q-TC间期呈负相关。  相似文献   
100.
目的:探讨有氧运动对大鼠胸主动脉内皮依赖性舒张功能影响的机制。方法:12只SD大鼠随机分为有氧运动和对照两组(n=6),经过8周每天1 h的游泳训练后(每周5天),测定比较2组间大鼠胸主动脉舒张功能的改变。结果:有氧运动组一氧化氮(NO)和前列环素PGI2途径胸主动脉舒张功能的Rmax值较对照组明显提高(P<0.05)。结论:有氧运动对大鼠胸主动脉舒张功能的有益影响,主要是由NO和PGI2途径介导的。  相似文献   
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