首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   121篇
  免费   4篇
  国内免费   1篇
  2021年   1篇
  2020年   1篇
  2019年   12篇
  2018年   4篇
  2017年   3篇
  2016年   1篇
  2015年   1篇
  2014年   29篇
  2013年   29篇
  2012年   11篇
  2011年   8篇
  2010年   7篇
  2009年   6篇
  2008年   3篇
  2007年   4篇
  2006年   3篇
  2005年   1篇
  2003年   1篇
  2002年   1篇
排序方式: 共有126条查询结果,搜索用时 15 毫秒
51.
The mouse prostate develops from a component of the lower urinary tract (LUT) known as the urogenital sinus (UGS). This process requires androgens and signaling between mesenchyme and epithelium. Little is known about DNA methylation during prostate development, including which factors are expressed, whether their expression changes over time, and if DNA methylation contributes to androgen signaling or influences signaling between mesenchyme and epithelium. We used in situ hybridization to evaluate the spatial and temporal expression pattern of mRNAs which encode proteins responsible for establishing, maintaining or remodeling DNA methylation. These include DNA methyltrasferases, DNA deaminases, DNA glycosylases, base excision repair and mismatch repair pathway members. The mRNA expression patterns were compared between male and female LUT prior to prostatic bud formation (14.5 days post coitus (dpc)), during prostatic bud formation (17.5 dpc) and during prostatic branching morphogenesis (postnatal day (P) 5). We found dramatic changes in the patterns of these mRNAs over the course of prostate development and identified examples of sexually dimorphic mRNA expression. Future investigation into how DNA methylation patterns are established, maintained and remodeled during the course of embryonic prostatic bud formation may provide insight into prostate morphogenesis and disease.  相似文献   
52.
The inactivation of tumor suppressor genes (TSGs) plays a vital role in the progression of human cancers. Nevertheless, those ubiquitous TSGs have been shown with limited roles in various stages of diverse carcinogenesis. Investigation on identifying unique TSG, especially for early stage of carcinogenesis, is imperative. As such, the search for organ-specific TSGs has emerged as a major strategy in cancer research. Prostate cancer (PCa) has the highest incidence in solid tumors in US males. Cellular prostatic acid phosphatase (cPAcP) is a prostate-specific differentiation antigen. Despite intensive studies over the past several decades on PAcP as a PCa biomarker, the role of cPAcP as a PCa-specific tumor suppressor has only recently been emerged and validated. The mechanism underlying the pivotal role of cPAcP as a prostate-specific TSG is, in part, due to its function as a protein tyrosine phosphatase (PTP) as well as a phosphoinositide phosphatase (PIP), an apparent functional homologue to phosphatase and tensin homolog (PTEN) in PCa cells. This review is focused on discussing the function of this authentic prostate-specific tumor suppressor and the mechanism behind the loss of cPAcP expression leading to prostate carcinogenesis. We review other phosphatases' roles as TSGs which regulate oncogenic PI3K signaling in PCa and discuss the functional similarity between cPAcP and PTEN in prostate carcinogenesis.  相似文献   
53.
54.
Defects in apoptotic pathway contribute to development and progression of oral cancer. Survivin, a member of the inhibitors of apoptosis protein (IAP) family, is increased in many types of cancers. However, it is unclear whether increased survivin is associated with oral squamous cell carcinomas (OSCC), and what mechanisms may involve in. In this study, we examined survivin expression in OSCC compared with normal oral tissues via immunohistochemical staining. The results showed that, not only total survivin is increased in OSCCs, but also the subcellular location of survivin is changed in OSCCs compared with normal oral tissues. In most of normal oral tissues, survivin staining was either negative, or cytoplasmic positive/nuclear negative; whereas in most of OSCC tissues, survivin staining was nuclear positive. Statistic analysis indicates that nuclear survivin, rather than total or cytoplasmic one, correlates with tumor TNM stage and differentiation grade. Consistently, in vitro analysis showed that survivin is in cytoplasm in normal human oral kinotinocyte (HOK) cells; whereas it is in nucleus in OSCC HN6 cells. Importantly, treatment of HOK cells with HDAC inhibitor Trichostatin A (TSA) induces survivin acetylation and promotes its nuclear localization. Moreover, nuclear survivin in OSCC cells was acetylated at K129 in its C-terminal, suggesting that the acetylation is important for nuclear location of survivin. Our study demonstrates that it is nuclear survivin, rather than total or cytoplasmic one, associates with TNM stage and tumor grade of OSCC. Thus, we propose nuclear survivin as a prognostic marker for the progression of OSCC.  相似文献   
55.
Prion diseases are transmissible spongiform encephalopathies (TSEs) characterized by fatal, progressive neurologic diseases with prolonged incubation periods and an accumulation of infectious misfolded prion proteins. Antemortem diagnosis is often difficult due to a long asymptomatic incubation period, differences in the pathogenesis of different prions, and the presence of very low levels of infectious prion in easily accessible samples. Chronic wasting disease (CWD) is a TSE affecting both wild and captive populations of cervids, including mule deer, white-tailed deer, elk, moose, muntjac, and most recently, wild reindeer. This study represents a well-controlled evaluation of a newly developed real-time quaking-induced conversion (RT-QuIC) assay as a potential CWD diagnostic screening test using rectal biopsy sections from a depopulated elk herd. We evaluated 69 blinded samples of recto-anal mucosa-associated lymphoid tissue (RAMALT) obtained from USDA Veterinary Services. The results were later un-blinded and statistically compared to immunohistochemical (IHC) results from the USDA National Veterinary Services Laboratories (NVSL) for RAMALT, obex, and medial retropharyngeal lymph node (MRPLN). Comparison of RAMALT RT-QuIC assay results with the IHC results of RAMALT revealed 92% relative sensitivity (95% confidence limits: 61.52–99.8%) and 95% relative specificity (95% confidence limits: 85.13–99%). Collectively, our results show a potential utility of the RT-QuIC assay to advance the development of a rapid, sensitive, and specific prion diagnostic assay for CWD prions.  相似文献   
56.
目的对比研究免疫组织化学(IHC)与荧光原位杂交(FISH)方法检测乳腺癌中C-erbB-2蛋白表达和HER2基因扩增,评估两种方法的实际应用价值。方法 IHC和FISH法分别检测58例乳腺癌组织中C-erbB-2蛋白表达和HER2基因扩增状况,并进行一致性分析。结果IHC检测蛋白阳性2+和3+共22例,占总病例的37.9%,58例乳腺癌中FISH检测出HER2基因扩增17例,占29.3%。IHC检测C-erbB-2蛋白3+的12例中11例HER2基因扩增阳性,1例无扩增;C-erbB-2蛋白2+者10例,其中5例可见HER2基因扩增;C-erbB-2蛋白1+者11例HER2基因扩增仅1例。C-erbB-2蛋白阴性病例共25例均未检测到基因扩增。结果显示IHC检测C-erbB-2蛋白与FISH检测HER2基因扩增状态有较高的一致性(k=0.681,P0.01),C-erbB-2蛋白阴性和3+标本与HER2基因扩增阳性率比较差异无统计学意义(P0.05);而C-erbB-2蛋白1+和2+病例与其HER2基因扩增差异具有统计学意义(P0.05)。结果 IHC检测C-erbB-2蛋白强阳性(3+)和阴性(0)与HER2基因扩增有较高的一致性,可作为临床是否应用Herceptin治疗的依据,而C-erbB-2蛋白2+和1+病例必须进一步行HER2基因扩增检测。  相似文献   
57.
Jing JJ  Li M  Yuan Y 《Gene》2012,497(2):237-242
Toll-like receptor 4 (TLR4) is critical in the recognition of Gram-negative bacteria serving as a key immune system effector. Recently, a number of case-control studies were conducted to investigate the association between TLR4 gene polymorphism and cancer risk, especially Asp299Gly and Thr399Ile polymorphisms. However, published data were still conflicting. In this paper, we summarized 9463 cancer cases and 10,825 controls from 22 studies and attempted to assess the susceptibility of TLR4 gene polymorphism to cancers by a synthetical meta-analysis. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the relationship. Our results suggested that Asp299Gly represented a risk factor on cancers in digestive system (G allele versus A allele, OR=1.64, 95% CI: 1.02-2.64; GA+GG versus AA, OR=1.64, 95% CI: 1.00-2.71) but tend to have a protective effect on prostate cancer (GG versus AA, OR=0.37, 95% CI: 0.14-0.98; GG versus GA+AA, OR=0.37, 95% CI: 0.14-0.98). Thr399Ile polymorphism was significantly associated with an elevated cancer risk in overall analysis (T allele versus C allele, OR=1.72, 95% CI: 1.27-2.33; TC versus CC, OR=1.63, 95% CI: 1.18-2.26; TT+TC versus CC, OR=1.70, 95% CI: 1.24-2.34) and especially in gastrointestinal subgroup (T allele versus C allele, OR=2.01, 95% CI: 1.40-2.89; TC versus CC, OR=1.86, 95% CI: 1.26-2.74; TT+TC versus CC, OR=1.97, 95% CI: 1.35-2.88). Further prospective researches with larger numbers of worldwide participants are warranted to draw comprehensive and true conclusions.  相似文献   
58.
Sha K  Conner WC  Choi DY  Park JH 《Gene》2012,497(2):191-199
In this article, we characterized structure and expression of genes encoding the neuropeptide Corazonin (MdCrz) and its putative receptor (MdCrzR) in the House Fly, Musca domestica. The MdCrz gene contains two introns, one within the 5' untranslated region and the other within the open reading frame. The 150-amino-acid precursor consists of an N-terminal signal peptide, and mature Crz followed by Crz-associated peptide (CAP). The CAP region is highly diverged from those of other insect precursors, whereas the mature Crz is identical in other dipteran members. In situ hybridization and immunohistochemistry consistently found a group of three MdCrz-producing neurons in the dorso-lateral protocerebrum, and eight pairs of bi-lateral neurons in the ventral nerve cord in the larvae. In adults, the expression was found exclusively in a cluster of five to seven neurons per brain lobe. Comparable expression patterns observed in other dipteran species suggest conserved regulatory mechanisms of Crz expression and functions during the course of evolution. MdCrzR deduced from the full-length cDNA sequence is a 655-amino acid polypeptide that contains seven trans-membrane (TM) domains and other motifs that are characteristics of Class-A G-protein coupled receptors. Although the TMs and loops between the TMs are conserved in other CrzRs, N-terminal extracellular domain is quite dissimilar. Tissue-specific RT-PCR revealed a high level of MdCrzR expression in the larval salivary glands and a moderate level in the CNS. In adults, the receptor was expressed both in the head and body, suggesting multifunctionality of the Crz signaling system.  相似文献   
59.
60.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号