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   4799篇
  免费   412篇
  国内免费   54篇
耳鼻咽喉   11篇
儿科学   187篇
妇产科学   78篇
基础医学   552篇
口腔科学   284篇
临床医学   508篇
内科学   794篇
皮肤病学   85篇
神经病学   327篇
特种医学   425篇
外国民族医学   1篇
外科学   542篇
综合类   182篇
现状与发展   1篇
一般理论   1篇
预防医学   463篇
眼科学   60篇
药学   337篇
  2篇
中国医学   77篇
肿瘤学   348篇
  2023年   56篇
  2022年   123篇
  2021年   153篇
  2020年   120篇
  2019年   78篇
  2018年   110篇
  2017年   75篇
  2016年   73篇
  2015年   105篇
  2014年   113篇
  2013年   153篇
  2012年   154篇
  2011年   172篇
  2010年   130篇
  2009年   100篇
  2008年   157篇
  2007年   188篇
  2006年   170篇
  2005年   169篇
  2004年   151篇
  2003年   136篇
  2002年   143篇
  2001年   116篇
  2000年   149篇
  1999年   129篇
  1998年   96篇
  1997年   94篇
  1996年   106篇
  1995年   87篇
  1994年   65篇
  1993年   79篇
  1992年   114篇
  1991年   111篇
  1990年   128篇
  1989年   128篇
  1988年   109篇
  1987年   75篇
  1986年   81篇
  1985年   92篇
  1984年   55篇
  1983年   54篇
  1982年   33篇
  1981年   40篇
  1980年   40篇
  1979年   40篇
  1978年   49篇
  1977年   44篇
  1976年   33篇
  1974年   33篇
  1973年   31篇
排序方式: 共有5265条查询结果,搜索用时 15 毫秒
1.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome.  相似文献   
2.
3.
Abstract: Data from the National Education Longitudinal Study were combined with census data at the zip code level to examine the impact of neighborhood racial and ethnic diversity and consolidated inequality, in addition to individual, family, and school factors, on the likelihood of dropping out of high school. Results indicate that while the effects for diversity and consolidated inequality did not support the stated hypotheses, main effects for family risk and prior academic achievement were significant and in the stated direction. Also, when controlling for individual, family, school, and neighborhood characteristics, African Americans were less likely than White students to drop out of school. Implications for contextual effects research and educational outcomes are discussed.  相似文献   
4.
5.
Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
  相似文献   
6.
This review focuses on selected areas that should interest both the scientist and the clinician alike: polymorphisms within the factor VIII and factor IX genes, their linkage, and their ethnic variation; a general assessment of mutations within both genes and a detailed inspection of the molecular pathology of certain mutations to illustrate the diverse cause–effect relations that exist; a summary of current knowledge on molecular aspects of inhibitor production; and an introduction to the new areas of factor VIII and factor IX catabolism. An appendix defining various terms encountered in the molecular genetics of the haemophilias is included, together with an appendix providing accession numbers and locus identification links for accessing gene and sequence information in the international nucleic acid databases.  相似文献   
7.
To better understand the potential environmental health risk presented by West Nile virus (WNV)-contaminated feces, we quantified the amount of WNV present in the feces of experimentally infected American crows (Corvus brachyrhynchos) and fish crows (Corvus ossifragus). Peak fecal titers ranged from 10(3.5) to 10(8.8) plaque-forming units (PFU)/g for 10 American crows and from 10(2.3) to 10(6.4) PFU/g for 10 fish crows. The presence of infectious WNV in bird feces indicates a potential for direct transmission of WNV. Thus, handlers of sick or dead birds should take appropriate precautions to avoid exposure to fecal material.  相似文献   
8.
9.
There is evidence that long-term maintenance of a low-fat diet reduces preference for high-fat foods. Sensory evaluation of the taste of fat, and preference for high and low-fat foods were studied in a group of former participants in a randomized dietary intervention trial aimed at lowering fat consumption. Intervention subjects consuming less than 25% of daily calories as fat and control subjects consuming more than 35% of daily calories as fat agreed to be in a "taste perception" study. In Study 1, subjects tasted 20 dairy solutions containing different levels of fat and sugar. Subjects rated the perceived intensity of fat taste, and of liking, for each of the solutions. In Study 2, subjects were asked to taste and rate 4 high-fat and 4 low-fat snack foods, and were then allowed to freely consume these foods in a preference test. Intervention and control subjects were similar in their sensory evaluation of the taste of fat in Study 1. In Study 2, intervention subjects reported a reduced hedonic rating of the taste of high-fat snack foods compared to control subjects, yet intervention subjects consumed the same amount of high-fat snack foods as control subjects. We conclude that a successful outcome in a dietary intervention may be due to social and cognitive factors, in addition to potential changes in hedonic response to fat.  相似文献   
10.
苑玉清  蔡博文  游潮 《四川医学》2004,25(8):842-843
目的 探讨急性重型颅脑损伤 (ASBI)患者血浆中内皮素 (ET)和降钙素基因相关肽 (CGRP)的含量变化及其临床意义。方法 用放免法测定 2 8例ASBI患者伤后 6~ 2 4h血浆中ET及CGRP含量。结果 ASBI患者ET含量明显增多 ,差别有显著性 (P <0 .0 5 ) ;CGRP也有一定的增多 ,但无显著性差异。结论 ET和CGRP共同参与ASBI病理生理反应过程 ,ET释放增加是加重脑继发性损害的重要因素  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