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71.
利用PCR方法,从阴离子交换蛋白1(AE1)全长cDNA中扩增出约350bp c末端cDNA片段,测序后将其克隆至pGADT7载体上,用醋酸锂法构建好的pADT7-AE1-c末端转染酵母菌HA109,观察其在选择性培养基上的表达情况。结果表明,获得了530bp AE1c-末端cDNA,pGADT7-AE1-c末端对酵母无毒性,不能激活检测基因,可作为酵母双杂合系统中的靶基因。  相似文献   
72.
Summary Kinematic variables of the vertical jump (jumping height, jump phase durations and joint angles) were measured on 39 male physical education students. In addition, kinetic parameters of the hip and knee extensors, and of the plantar flexors (maxima voluntary force and its rate of development) were recorded on the same subjects, in isometric conditions. The results demonstrated significant positive correlations between kinetic parameters of the active muscle groups and jumping height (r=0.217−0.464). The dominant effect on these correlations was due to the knee extensors. Correlations between these parameters and the duration of the jump phases were much weaker. Correlation coefficients between kinetic parameters and limb angles in the lowest body position showed that fast force production in one muscle group was related to a significant decrease in the joint angles of distant body segments. Multiple correlation coefficients between leg extensor parameters and kinematic variables (ranging between 0.256 for the duration of the counter-movement phase and 0.616 for jump height) suggested that kinetic parameters could explain more than a quarter of the variability of this complex human movement. Therefore, the conclusion was drawn that an extended set of measurements of the relevant musculo-skeletal system parameters could predict a considerable amount of the variability of human movement. However, high correlation coefficients between the same kinetic parameters of different muscle groups suggest that not all active muscle groups have to be included in the measurements.  相似文献   
73.
Zebrafish SmyD1 is a SET and MYND domain-containing protein that plays an important role in myofiber maturation and muscle contraction. SmyD1 is required for myofibril organization and sarcomere assembly during myofiber maturation. Whole-mount in situ hybridization revealed that smyd1 mRNAs are specifically expressed in skeletal and cardiac muscles in zebrafish embryos. However, it is unknown if smyd1 is expressed in other striated muscles, such as cranial and fin muscles, and moreover, the regulatory elements required for its muscle-specific expression. We report here the analyses of smyd1 expression using smyd1-gfp transgenic zebrafish. smyd1-gfp transgenic zebrafish were generated using the 5.3-kb smyd1 promoter and its 5'-flanking sequence. GFP expression was found in the skeletal and cardiac muscles of smyd1-gfp transgenic embryos. GFP expression appeared stronger in slow muscles than fast muscles in transgenic zebrafish larvae. In addition, GFP expression was also detected in cranial and fin muscles of smyd1-gfp transgenic zebrafish larvae. In situ hybridization confirmed smyd1 mRNA expression in these tissues, suggesting that the expression of the smyd1-gfp transgene recapitulated that of the endogenous smyd1 gene. Deletion analysis revealed that the 0.5-kb sequence in the proximal promoter of smyd1 was essential for its muscle specificity. Together, these data indicate that smyd1 is specifically expressed in most, if not all, striated muscles, and the muscle specificity is controlled by the 5.3-kb promoter and flanking sequences.  相似文献   
74.
Human malignant glioma grown in athymic nude mice (NHG-1) and three freshly resected human solid gliomas were used in the study of factors influencing the direct preparation (DP) for chromosome analysis of human solid tumors. The results showed that: 1) the length of time after the blood supply was obstructed was a major factor in reducing the success rate of DP, i.e., a 2-hour delay resulted in a significantly lowered metaphase number and after 4 hours almost no metaphases could be seen; 2) preserving tumor cells at 4 degrees C may prolong the time limit to about 4 hours; 3) culture medium (RPMI 1640 and Eagle MEM) and bovine calf serum concentration (0%, 10%, 20%, and 30%) did not influence the success rate significantly; 4) colchicine concentration (0.025 micrograms/mL, 0.05 micrograms/mL, 0.1 micrograms/mL) and time of treatment (30 min, 90 min, or 180 min) mainly affected the quality of chromosomes observed but had little effect on the quantity of metaphases that might be obtained. Based on these results, we had a success rate of more than 80% in 72 xenografts and 22 human brain tumors.  相似文献   
75.
76.
向大白鼠脊髓的颈、腰膨大和胸髓右侧半分别注入HRP或WGA—HRP,研究了脊髓向延髓外侧网状核的投射。 1.双侧的三叉神经下亚核同时接受颈、胸和腰髓来的投射。 2.大白鼠脊髓主要投射于外侧网状核的尾侧半,有一定的体部定位关系。颈髓投射于双侧大细胞亚核的外侧2/3及与共相邻接的一部分小细胞亚核内,以同侧投射为主。胸髓投射于双侧的大细胞亚核的内侧2/3和与之相邻接的一部分小细胞亚核内,两侧无明显差別。腰髓投射于双侧小细胞亚核和与之相邻接的部分大细胞亚核内,以对侧投射为主。它们相互间有部分重叠。 3.颈、胸和腰髓内外侧网状核投射的神经元位于从背角至腹角的灰质内,越边投射的神经元比不越边投射的神经元位置更靠腹侧。  相似文献   
77.
Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is important for downregulation of T-cell activation, and CTLA-4 gene polymorphisms have been implicated as risk factors for rheumatoid arthritis (RA). Previous studies of the association between the +49 polymorphism of the CTLA-4 gene in RA have provided conflicting results. In order to determine association of the CTLA-4 gene with RA in Chinese Han population, we used denaturing gradient gel electrophoresis (DGGE) to genotype polymorphisms of four SNPs (MH30, +49, CT60 and JO31) of the CTLA-4 gene in 326 RA patients and 250 healthy controls. Furthermore, meta-analysis of all available studies relating +49 polymorphism to the risk of RA was performed to confirm the disease association. Among the SNPs examined, the genotype frequencies of CTLA-4 +49 and CT60 in RA patients differed significantly from controls (P=0.028 and 0.007). In addition, the distribution of four haplotypes constructed by these two SNPs was significantly different between patients and controls (chi(2)=10.58, d.f. =3, P=0.014). The meta-analysis also revealed that in both European and Asian populations, the CLTA-4 +49 G allele was associated with the risk of RA. These results suggested that the CTLA-4 gene might be involved in the susceptibility to RA in the Chinese Han population and both +49 and CT60 of CTLA-4 gene might be the causal variants in RA disease.  相似文献   
78.
白细胞介素1刺激破骨细胞性骨吸收作用的实验研究   总被引:3,自引:2,他引:1  
目的:了解白细胞介素1β(IL-1β)在破骨细胞性骨吸收中的刺激作用及其相应的作用机制。方法:分别将新生大鼠破骨细胞单独以及和成骨细胞联合接种于预置象牙片的培养板中。24h后培养液中加入不同浓度的IL-1β。继续培养48h,然后取出象牙片,超声处理后行甲苯胺蓝染色,光镜下观察骨吸收陷窝的数目并计算其部面积。结果:IL-1β能够明显增加坡骨细胞和成骨细胞联合培养组象牙片上吸收陷窝的数目和面前,且刺激作用呈剂量依赖性,但对单独培养的破骨细胞无明显刺激作用。结论:IL-1β的刺激骨吸收作用由成骨细胞所介导,而非直接作用于破骨细胞。  相似文献   
79.
目的 分析小儿再发性腹痛的病因以及相关的因素为临床选择辅助检查及诊断提供依据或参考。方法 268例再发性腹痛患儿选人调查对象,对其进行病因学调查,调查内容包括年龄、性别、季节、诱因、部位等8个因素,进行分析。选择相关的辅助检查确定病因。结果 有52例有器质性疾病(19.4%),以慢性胃炎居首位。与发作有关的因素有季节、年龄、情绪反应。结论 小儿再发性腹痛绝大多数属于功能性疾病,只有少数由器质性原因引起,但仍应引起足够重视,谨慎的选择辅助检查,避免漏诊。  相似文献   
80.
1987年1月至2000年4月,共施行人工机械瓣膜替换手术700例,其中二尖瓣替换术398例,主动脉瓣替换术81例,二尖瓣和主动脉瓣替换术213例,三尖瓣替换术8例.158例患者术中和术后早期发生并发症,发生率为22.6%,死亡44例,死亡率6.3%.死亡原因主要为低心排出量综合征、严重感染和心律失常等.  相似文献   
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