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   361619篇
  免费   19216篇
  国内免费   11346篇
耳鼻咽喉   2530篇
儿科学   9168篇
妇产科学   5112篇
基础医学   41565篇
口腔科学   4924篇
临床医学   35919篇
内科学   55870篇
皮肤病学   2734篇
神经病学   24835篇
特种医学   15161篇
外国民族医学   82篇
外科学   45037篇
综合类   35714篇
现状与发展   44篇
一般理论   17篇
预防医学   32647篇
眼科学   7271篇
药学   31213篇
  175篇
中国医学   12048篇
肿瘤学   30115篇
  2024年   736篇
  2023年   2825篇
  2022年   7122篇
  2021年   9125篇
  2020年   6918篇
  2019年   5906篇
  2018年   27621篇
  2017年   22958篇
  2016年   24615篇
  2015年   9083篇
  2014年   11061篇
  2013年   11033篇
  2012年   21274篇
  2011年   35984篇
  2010年   29695篇
  2009年   20612篇
  2008年   29965篇
  2007年   32167篇
  2006年   10292篇
  2005年   10902篇
  2004年   9946篇
  2003年   10642篇
  2002年   7893篇
  2001年   4711篇
  2000年   4252篇
  1999年   3396篇
  1998年   2209篇
  1997年   2323篇
  1996年   1598篇
  1995年   1543篇
  1994年   1394篇
  1993年   931篇
  1992年   1170篇
  1991年   1134篇
  1990年   1051篇
  1989年   931篇
  1988年   804篇
  1987年   722篇
  1986年   649篇
  1985年   531篇
  1984年   443篇
  1983年   376篇
  1982年   319篇
  1981年   259篇
  1980年   269篇
  1979年   225篇
  1978年   225篇
  1977年   231篇
  1976年   212篇
  1974年   189篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
993.
Thirty-five posters were presented at the Workshop on Brain Uptake And Utilization Of Fatty Acids, Lipids, and Lipoproteins. They were grouped into four categories: (1) mechanisms of lipid uptake and transport to the brain, (2) lipoproteins and polyunsaturated fatty acids, (3) eicosanoids in brain function, and (4) fatty acids and lipids in brain disorders. This article summarizes the highlights of the research presented in these posters. The individual abstracts follow these synopses.  相似文献   
994.
目的:探讨MEBO治疗骨外露的临床疗效。方法:对2005年10月至2006年2月处置外伤性指(趾)骨外露3例采用MEBO治疗。结果:3例创面全部愈合,时间均为3周。结论:MEBO治疗外伤性末节指(趾)骨外露简便,实用,疗效可靠,不影响美观。  相似文献   
995.
996.
997.
Not many data exist to guide us in the management of patients with chronic hepatitis B virus infection and “normal” alanine aminotransferase levels. Many of these patients may not have normal levels on long-term follow-up or when the upper limit of normal is determined from a truly healthy reference population. These patients may have significant histologic disease and benefit from further investigation or treatment. This article focuses on the disease course of such patients.  相似文献   
998.
Genes influencing the autonomic nervous system continue as a focus of research. Recent publications applied different methods to identify genes influencing autonomic cardiovascular regulation in humans. Two reports relied on a candidate gene approach. Common genetic polymorphisms in the promoter region of the tyrosine hydroxylase gene were shown to influence catecholamine synthesis and blood pressure. The same group tested the hypothesis that the GTP cyclohydrolase 1 (GCH1) gene influences catecholamine excretion and cardiovascular regulation. GCH1 affects tyrosine hydroxylase function indirectly. The authors concluded that the GCH1 gene may influence cardiovascular autonomic regulation through changes in nitric oxide production rather than a change in tyrosine hydroxylase activity. The third genetic study used a single nucleotide polymorphism chip to analyze 100,000 genetic polymorphisms scattered throughout the genome in participants of the Framingham study. The authors identified several polymorphisms that may influence QT interval duration, heart rate, and heart rate variability. The respective genes have not been identified with certainty. Another study suggested that catecholamines may be released from phagocytes and regulate pulmonary inflammation through alpha-2 adrenoreceptor activation in an autocrine or paracrine fashion.  相似文献   
999.
目的 建立检测人CEA的T7 RNA聚合酶催化的荧光扩增技术.方法 以亲和素作为连接分子,连接生物素化的检测抗体和生物素化的DNA,加入T7RNA聚合酶进行转录扩增反应,对生成的RNA产物进行荧光检测,并同时进行夹心ELISA方法检测人CEA.结果 成功的建立了检测人CEA的T7 RNA聚合酶催化的荧光扩增技术,其检测CEA的灵敏度达2×10 -3 ng/ml,比夹心EL ISA 方法灵敏度高125倍.结论 T7 RNA聚合酶催化的荧光扩增技术较夹心ELISA方法具有更高的敏感性,有可能作为一种新的检测方法用于临床的早期诊断.  相似文献   
1000.
Examination is a cornerstone in the manual procedures leading to mobilisation/manipulation of the low back. The observer variation of the more specific segmental tests remains to be investigated. Two skilled specialists in manual medicine examined the segmental changes in the lumbar spine. The patients were unknown to the examiners and no information of the case history was given. All test results were recorded by an observer present in the room who ensured that no conversation was allowed during the examination. The primary outcome measures were the kappa values for each test. The matching was defined as acceptable (acc) within two neighbouring levels and perfect (per) on the same level. Intra-observer variation (tested in 33 patients and 10 subjects without low-back pain): The agreement between first and second segmental diagnosis examination was 70% (per) and 82% (per + acc). Kappa values were: segmental diagnosis 0.60 (per) and 0.70 (per + acc), multifidus test 0.51 (per) and 0.60 (per + acc), sideflexion 0.57 (per) and 0.69 (per + acc), and ventral flexion 0.31 (per) and 0.45 (per + acc). Inter-observer variation (tested in 60 patients): The agreement for segmental diagnosis between the examiner A and B was 42% (per) and 75% (per + acc). Kappa values were: segmental diagnosis 0.21 (per) and 0.57 (acc), multifidus test 0.12 (per) and 0.48 (acc), sideflexion 0.22 (per) and 0.45 (acc), and ventralflexion 0.22 (per) and 0.44 (acc). By manual tests, skilled examiners seem to be able to diagnose segmental dysfunctions in the low back. The clinical implication of these dysfunctions remains to be clarified.  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