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   60636篇
  免费   3854篇
  国内免费   1058篇
耳鼻咽喉   555篇
儿科学   1445篇
妇产科学   1538篇
基础医学   6849篇
口腔科学   1408篇
临床医学   5109篇
内科学   14656篇
皮肤病学   879篇
神经病学   5929篇
特种医学   2239篇
外国民族医学   2篇
外科学   8651篇
综合类   2111篇
现状与发展   1篇
一般理论   3篇
预防医学   2900篇
眼科学   840篇
药学   4685篇
  8篇
中国医学   967篇
肿瘤学   4773篇
  2023年   537篇
  2022年   1239篇
  2021年   2227篇
  2020年   1381篇
  2019年   1617篇
  2018年   1774篇
  2017年   1445篇
  2016年   1517篇
  2015年   1864篇
  2014年   2443篇
  2013年   3095篇
  2012年   4121篇
  2011年   4217篇
  2010年   2432篇
  2009年   2256篇
  2008年   3398篇
  2007年   3433篇
  2006年   3115篇
  2005年   2989篇
  2004年   2772篇
  2003年   2331篇
  2002年   2112篇
  2001年   1498篇
  2000年   1383篇
  1999年   1308篇
  1998年   574篇
  1997年   448篇
  1996年   438篇
  1995年   343篇
  1994年   318篇
  1993年   258篇
  1992年   702篇
  1991年   594篇
  1990年   573篇
  1989年   580篇
  1988年   472篇
  1987年   431篇
  1986年   421篇
  1985年   325篇
  1984年   277篇
  1983年   229篇
  1982年   141篇
  1981年   110篇
  1979年   219篇
  1978年   134篇
  1977年   114篇
  1974年   124篇
  1973年   128篇
  1972年   124篇
  1971年   111篇
排序方式: 共有10000条查询结果,搜索用时 225 毫秒
991.
Puppa G, Senore C, Sheahan K, Vieth M, Lugli A, Zlobec I, Pecori S, Wang L M, Langner C, Mitomi H, Nakamura T, Watanabe M, Ueno H, Chasle J, Conley S A, Herlin P, Lauwers G Y & Risio M
(2012) Histopathology  61, 562–575 Diagnostic reproducibility of tumour budding in colorectal cancer: a multicentre, multinational study using virtual microscopy Aims: Despite the established prognostic relevance of tumour budding in colorectal cancer, the reproducibility of the methods reported for its assessment has not yet been determined, limiting its use and reporting in routine pathology practice. Methods and results: A morphometric system within telepathology was devised to evaluate the reproducibility of the various methods published for the assessment of tumour budding in colorectal cancer. Five methods were selected to evaluate the diagnostic reproducibility among 10 investigators, using haematoxylin and eosin (H&E) and AE1‐3 cytokeratin‐immunostained, whole‐slide digital scans from 50 pT1–pT4 colorectal cancers. The overall interobserver agreement was fair for all methods, and increased to moderate for pT1 cancers. The intraobserver agreement was also fair for all methods and moderate for pT1 cancers. Agreement was dependent on the participants’ experience with tumour budding reporting and performance time. Cytokeratin immunohistochemistry detected a higher percentage of tumour budding‐positive cases with all methods compared to H&E‐stained slides, but did not influence agreement levels. Conclusions: An overall fair level of diagnostic agreement for tumour budding in colorectal cancer was demonstrated, which was significantly higher in early cancer and among experienced gastrointestinal pathologists. Cytokeratin immunostaining facilitated detection of budding cancer cells, but did not result in improved interobserver agreement.  相似文献   
992.
993.
994.
995.
996.
997.
998.
Acute pancreatitis is being diagnosed more frequently in pediatrics and there is limited published research to guide management. In contrast, multiple prospective studies in the adult population have resulted in significant changes in the way the disease is managed, especially with regard to severe disease. The nutritional management of pediatric acute pancreatitis appears to lag behind current adult recommendations, likely resulting from a lack of awareness of the adult data, inherent differences between pediatric and adult pancreatitis, and the paucity of research performed in children. The purpose of this review is to examine the adult literature regarding the nutritional management of acute pancreatitis and discuss the possible relevance of this data in the pediatric population.  相似文献   
999.
1000.
Background Glutamine (Gln) is an abundant nutrient used by cancer cells. Breast cancers cells and particularly triple-receptor negative breast cancer (TNBC) are reported to be dependent on Gln to produce the energy required for survival and proliferation. Despite intense research on the role of the intracellular Gln pathway, few reports have focussed on Gln transporters in breast cancer and TNBC.Methods The role and localisation of the Gln transporter SLC38A2/SNAT2 in response to Gln deprivation or pharmacological stresses was examined in a panel of breast cancer cell lines. Subsequently, the effect of SLC38A2 knockdown in Gln-sensitive cell lines was analysed. The prognostic value of SLC38A2 in a cohort of breast cancer was determined by immunohistochemistry.Results SLC38A2 was identified as a strongly expressed amino acid transporter in six breast cancer cell lines. We confirmed an autophagic route of degradation for SLC38A2. SLC38A2 knockdown decreased Gln consumption, inhibited cell growth, induced autophagy and led to ROS production in a subgroup of Gln-sensitive cell lines. High expression of SLC38A2 protein was associated with poor breast cancer specific survival in a large cohort of patients (p = 0.004), particularly in TNBC (p = 0.02).Conclusions These results position SLC38A2 as a selective target for inhibiting growth of Gln-dependent breast cancer cell lines.Subject terms: Breast cancer, Cancer metabolism  相似文献   
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