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   55142篇
  免费   4936篇
  国内免费   101篇
耳鼻咽喉   703篇
儿科学   1712篇
妇产科学   1296篇
基础医学   7278篇
口腔科学   1280篇
临床医学   5911篇
内科学   11037篇
皮肤病学   756篇
神经病学   4641篇
特种医学   1799篇
外国民族医学   9篇
外科学   7874篇
综合类   1041篇
一般理论   47篇
预防医学   5786篇
眼科学   1294篇
药学   4064篇
中国医学   55篇
肿瘤学   3596篇
  2022年   357篇
  2021年   900篇
  2020年   506篇
  2019年   909篇
  2018年   1047篇
  2017年   815篇
  2016年   805篇
  2015年   921篇
  2014年   1424篇
  2013年   2059篇
  2012年   3077篇
  2011年   3099篇
  2010年   1686篇
  2009年   1526篇
  2008年   2823篇
  2007年   2993篇
  2006年   2967篇
  2005年   2835篇
  2004年   2617篇
  2003年   2411篇
  2002年   2351篇
  2001年   1366篇
  2000年   1416篇
  1999年   1247篇
  1998年   598篇
  1997年   506篇
  1996年   506篇
  1995年   452篇
  1994年   449篇
  1993年   418篇
  1992年   1054篇
  1991年   1055篇
  1990年   958篇
  1989年   890篇
  1988年   813篇
  1987年   815篇
  1986年   799篇
  1985年   777篇
  1984年   664篇
  1983年   533篇
  1982年   427篇
  1981年   380篇
  1980年   333篇
  1979年   611篇
  1978年   400篇
  1976年   320篇
  1975年   374篇
  1974年   402篇
  1973年   357篇
  1972年   324篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   
3.
4.
Epidermolysis bullosa simplex (EBS) is a skin fragility disorder resulting from mutations of structural proteins in the epidermis. We provide a brief report of long‐term survival and reproduction in a mother with EBS due to keratin 5 (KRT5) c.1429G > A (p.E477K) mutation, which causes a particularly severe form of the disease.  相似文献   
5.
6.
7.
ABSTRACT

Abortion is legal in South Africa, but negative abortion attitudes remain common and are poorly understood. We used nationally representative South African Social Attitudes Survey data to analyze abortion attitudes in the case of fetal anomaly and in the case of poverty from 2007 to 2016 (n = 20,711; ages = 16+). We measured correlations between abortion attitudes and these important predictors: religiosity, attitudes about premarital sex, attitudes about preferential hiring and promotion of women, and attitudes toward family gender roles. Abortion acceptability for poverty increased over time (b = 0.05, p < .001), but not for fetal anomaly (b = ?0.008, p = .284). Highly religious South Africans reported lower abortion acceptability in both cases (Odds Ratio (OR)anomaly = 0.85, p = .015; ORpoverty = 0.84, p = .02). Premarital sex acceptability strongly and positively predicted abortion acceptability (ORanomaly = 2.63, p < .001; ORpoverty = 2.46, p < .001). Attitudes about preferential hiring and promotion of women were not associated with abortion attitudes, but favorable attitudes about working mothers were positively associated with abortion acceptability for fetal anomaly ((ORanomaly = 1.09, p = .01; ORpoverty = 1.02, p = .641)). Results suggest negative abortion attitudes remain common in South Africa and are closely tied to religiosity, traditional ideologies about sexuality, and gender role expectations about motherhood.  相似文献   
8.
Quality of Life Research - This study investigated the PROMIS Self-Efficacy Measure for Managing Chronic Conditions (PROMIS-SE) domain distributions and examined the factor structure of the...  相似文献   
9.
10.
Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc.  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