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991.
Transcriptome analysis in blastocyst hatching by cDNA microarray 总被引:1,自引:0,他引:1
Chen HW Chen JJ Yu SL Li HN Yang PC Su CM Au HK Chang CW Chien LW Chen CS Tzeng CR 《Human reproduction (Oxford, England)》2005,20(9):2492-2501
BACKGROUND: Hatching is an important process for early embryo development, differentiation and implantation. However, little is known about its regulatory mechanisms. By integrating the technologies of RNA amplification and cDNA microarrays, it has become possible to study the gene expression profile at this critical stage. METHODS: Pre-hatched and hatched ICR mouse embryos (25 blastocysts in each group were used in the triplicate experiments) were collected for RNA extraction, amplification, and microarray analysis (the mouse cDNA microarray, 6144 genes, including expressed sequence tags). RESULTS: According to cDNA microarray data, we have identified 85 genes that were expressed at a higher level in hatched blastocyst than in pre-hatched blastocysts. In this study, 47 hatching-related candidate genes were verified via re-sequencing. Some of these genes have been selected and confirmed by real-time quantitative RT-PCR. These hatching-specific genes were also expressed at a lower level in the delayed growth embryos (morula or blastocyst without hatching at day 6 post hCG). These genes included: cell adhesion and migration molecules [E-cadherin, neuronal cell adhesion molecule (NCAM), lectin, galactose binding, soluble 7 (Lgals7), vanin 3 and biglycan], epigenetic regulators (Dnmt1, and SIN3 yeast homolog A), stress response regulators (heme oxygenase 1) and immunoresponse regulators [interleukin (IL)-2-inducible T-cell kinase, IL-4R, interferon-gamma receptor 2, and neurotrophin]. The immunostaining of E-cadherin and NCAM showed strong and specific localization in hatched blastocyst. CONCLUSIONS: This work provides important information for studying the mechanisms of blastocyst hatching and implantation. These hatching-specific genes may have potential as new drug targets for controlling fertility. 相似文献
992.
This study analyzed the expression of anti-islet autoantibodies and HLA-DR and -DQ genotypes in Korean children with type 1 diabetes mellitus (T1DM). The positivity of the anti-ICA512, anti-GAD65, and anti-insulin autoantibodies in the newly onset T1DM patients (n = 15) was 66.7%, 86.7%, and 46.7%, respectively, and all of them had one or more of the autoantibodies. HLA analysis showed higher frequencies of HLA-DRB1*0301, *0405, *09012 and -DQB1*0201, *0401, *03032 alleles in T1DM patients compared to controls (P(c) < 0.05). Because HLA-DQB1*0401, *03032 alleles carry aspartic acid at position 57 of DQB, susceptibility to T1DM in Korean children was not related to the presence of aspartic acid at position 57 of DQB1 locus. We suggest this unique HLA-DR, -DQ allele distribution might be an important factor for the low incidence of T1DM in Korea, and the combined anti-islet autoantibody assays could be valuable screening markers for the early detection of T1DM in Korea. 相似文献
993.
A microplate enzyme-linked immunosorbent assay was developed to detect chicken anti-rovirus antibodies. Studies of the parameters which affect the outcome of the assay with avian serum revealed two aspects for a successful assay. First, enzyme-antibody conjugates prepared by the periodate oxidation technique were found to have retained far more immunological activity than conjugates produced by a glutaraldehyde cross-linking. Second, the results indicated an unusually high affinity of chicken immunoglobulin for the microplate plastic which was mostly eliminated by a pretreatment technique with fixed fetal calf serum. The enzyme-linked immunosorbent assay compared favorably with the latex passive agglutination test, yielding a titration endpoint of 1:511,000, or approximately 1,300 times more sensitive than the latex passive agglutination assay. The assay proved not only to be sensitive to less than 1 ng of specific antibody, but also to have low to moderate variance and high reliability. 相似文献
994.
如何从脑电信号中快速准确地识别出P300成分是脑-机接口研究中的一个热点问题.针对P300的识别问题,我们提出了一种将F-score特征选择与支持向量机相结合的判别方法,该方法采用F-score特征选择减少输入特征的维数,以克服支持向量机算法判别速度慢的缺点;然后借助支持向量机算法良好的分类性能实现P300的识别.本文在BCI Competition 2003的P300实验数据集上对该方法进行了验证,结果表明,在5次重复实验中该方法的识别准确率达到了100%,且判别速度与未经特征选择的传统支持向量机算法相比提高了近2倍. 相似文献
995.
Recurrent genetic alterations in 26 colorectal carcinomas and 21 adenomas from Chinese patients 总被引:5,自引:0,他引:5
He QJ Zeng WF Sham JS Xie D Yang XW Lin HL Zhan WH Lin F Zeng SD Nie D Ma LF Li CJ Lu S Guan XY 《Cancer Genetics and Cytogenetics》2003,144(2):112-118
Colorectal cancer (CRC) is one of the most common malignancies worldwide. The incidence of CRC in the Chinese population has increased dramatically during the last two decades; however, nonrandom chromosomal alterations in Chinese patients have not been described. In the present study, comparative genomic hybridization (CGH) was applied to detect recurrent chromosome alterations in 26 primary colorectal carcinomas and 21 colorectal adenomas from Chinese patients. In CRC, several recurrent chromosomal changes were found, including gains of 8q (14/26 cases, 54%), 20q (54%), 3q (50%), 13q (50%), 5p (46%), 7p (42%), 7q (42%), and 12p (38%) and losses of 18q (65%) and 17p (42%). From comparison with previous CGH studies, the frequent gains of 3q and 12p might be distinctive occurrences in Chinese patients. The distribution of frequently found chromosomal alterations in different locations was studied. The gain of 20q was more frequently found in colon cancer (P<0.01) and the gain of 12p was more frequently found in rectal cancer. Chromosomal alterations were found in 19/21 of adenomas; the most frequent chromosomal alteration was the loss of 18q (9/21 cases, 43%). These recurrent alterations provide several starting points for the isolation of candidate oncogenes and tumor suppressor genes. 相似文献
996.
背景:目前临床上多数认为,肩部疾病如肩锁关节脱位、肩峰下撞击综合征等与肩锁关节的解剖形态有很大的关系,但国内外文献很少有关于肩锁关节的形态学数据支持,特别对于肩锁关节关节盘的解剖学研究。同时肩锁关节属于微动关节,参与肩关节的联合运动,现临床上有关肩锁关节脱位的手术方式繁多,较流行的手术方式多为刚性固定,并未保留其微动特点以及锁骨和肩胛骨的运动特点,其中关节盘的取舍目前国内外并无大样本多中心对照研究。目的:对肩锁关节及关节盘行相关解剖学研究,用于更好地指导肩部疾病的诊治。方法:对58具肩锁关节尸体标本(同济大学解剖教研室提供)进行形态学及组织结构研究,共获得58个肩峰、58个锁骨和36个关节盘(包括完全型和不完全型)。采用BIGLIANI肩峰形态分型、DEPALMA锁骨形态分型、EMURA肩锁关节盘分型,获得各肩峰与锁骨组合下关节盘出现的频率并行苏木精-伊红染色(上海市普陀区人民医院提供)。结果与结论:①在58个肩锁关节尸体中,肩锁关节盘type1型共15例,所占比例最高,为25.9%;type3a型共4例,所占比例最少,为6.9%。②Ⅰ型肩峰32个,所占比例最高,为55.2%;Ⅲ型肩峰3个,所占比例最低,为5.2%。③Ⅰ型锁骨27个,所占比例最高,为46.6%;Ⅲ型锁骨9个,所占比例最低,为15.5%。④以Ⅰ型及Ⅱ型肩峰与Ⅰ型锁骨组合所占比例较大,分别为24.1%和22.4%,以Ⅲ型肩峰对Ⅰ型锁骨所占比例最小,为0%。⑤而在Ⅰ型肩峰与Ⅰ型锁骨组合下type1型和type2b型关节盘所占比例最大,分别为35.7%和28.6%;Ⅱ型肩峰与Ⅰ型锁骨组合下type2a型和type1型关节盘所占比例最大,分别为38.5%和23.1%。⑥苏木精-伊红染色在组织切片中可以发现,关节盘中的细胞外基质清晰可辨,细胞形态饱满,含有丰富的细胞质,提示为软骨细胞,即形成纤维软骨的主要成分。此外,从关节囊顶端和底端两侧可见部分骨膜纤维层移行至关节盘内侧,考虑共同组成关节盘结构,即关节盘由近骨面的软骨细胞及远离骨面的纤维层共同构成。 相似文献
997.
益尔力口服液主治强力疲劳、气血虚损引起的肢体疲倦、精神不振、举动乏力。用葸酮法研究表明,其对肝糖原合成有明显促进作用,可作为扶正固本指标之一。 相似文献
998.
人工假肢膝关节微电脑控制装置的研究 总被引:1,自引:0,他引:1
高位截肢的伤残病人,即使安装了人工假肢,也因为人工假肢的关节不能自由活动,因而行走起来很吃力,动作不协调,姿态不美观。如果在人工假肢的关节处安装一个步进电机,采用微电脑控制技术,使步进电机按照人的意志转动,那么人在行走(或奔跑、弹跳、上下楼梯、下蹬起立等)时,假肢的逼真程度将会大大提高,动作也就十分自然。本文就这种构想谈了制作过程。 相似文献
999.
本文报道以RDS立体图作为检测图形,用液晶开关实现其三维立体显示的一些探索性研究,用液晶开关眼镜作为立体图的同步分离部件。使得本系统建立于继时法成像的基础上,因而消除了“红绿竞争”等影响检出精度的因素;系统采用帧频作为同步切换的总控信号,使CRT的视页切换与液晶眼镜开关同步,为此而开发出的显示寄存器编程技术解决了CRT视页切换的超高速要求。 相似文献
1000.