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   185570篇
  免费   34105篇
  国内免费   2668篇
耳鼻咽喉   5423篇
儿科学   5987篇
妇产科学   2775篇
基础医学   8010篇
口腔科学   2501篇
临床医学   28678篇
内科学   56190篇
皮肤病学   8313篇
神经病学   17205篇
特种医学   7633篇
外科学   47188篇
综合类   378篇
现状与发展   72篇
一般理论   2篇
预防医学   7975篇
眼科学   4072篇
药学   3115篇
中国医学   146篇
肿瘤学   16680篇
  2024年   524篇
  2023年   4941篇
  2022年   1582篇
  2021年   3920篇
  2020年   6435篇
  2019年   2777篇
  2018年   8177篇
  2017年   7940篇
  2016年   9131篇
  2015年   9166篇
  2014年   16482篇
  2013年   16904篇
  2012年   7615篇
  2011年   8024篇
  2010年   11751篇
  2009年   15347篇
  2008年   7979篇
  2007年   6444篇
  2006年   8730篇
  2005年   6217篇
  2004年   5409篇
  2003年   4405篇
  2002年   4520篇
  2001年   4220篇
  2000年   3432篇
  1999年   3772篇
  1998年   4228篇
  1997年   3933篇
  1996年   3810篇
  1995年   3580篇
  1994年   2285篇
  1993年   1871篇
  1992年   1663篇
  1991年   1675篇
  1990年   1303篇
  1989年   1412篇
  1988年   1220篇
  1987年   1036篇
  1986年   1059篇
  1985年   885篇
  1984年   710篇
  1983年   646篇
  1982年   601篇
  1981年   503篇
  1980年   455篇
  1979年   390篇
  1978年   385篇
  1977年   444篇
  1975年   304篇
  1972年   312篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
Gray platelet syndrome (GPS) is a rare (<1/1 000 000) and inherited platelet function disorder characterized by macrothrombocytopenia, α-granule deficiency, and hemorrhages. Bleeding intensity does not correlate with platelet count nor with functional test results. We hereby describe the perioperative bleeding prevention and management of a patient with GPS requiring multiple redo cardiac surgeries.  相似文献   
64.
65.
66.
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   
67.
68.
69.
Sessile serrated adenoma/polyps (SSA/Ps) are early precursor lesions in the serrated neoplasia pathway, which results in BRAF‐mutated colorectal carcinomas with not only high levels of microsatellite instability but also microsatellite stable. SSA/Ps with advanced histology, including cytological dysplasia or minimally invasive carcinomas, are important lesions because SSA/Ps are considered major contributors to “interval cancers” and these lesions can rapidly become dysplastic or invasive carcinomas. Clinicopathologically, SSA/Ps with dysplasia or invasive carcinoma were associated with advanced age, female sex, and proximal colon. Although SSA/Ps with submucosal invasive carcinoma were smaller and invaded less deeply into the submucosal layer than conventional tubular adenomas with submucosal invasive carcinoma, SSA/Ps with submucosal invasive carcinoma frequently had a mucinous component and exhibited a higher potential for lymphatic invasion and lymph node metastasis. In an SSA/P series, endoscopic characteristics, including (semi)pedunculated morphology, double elevation, central depression, and reddishness, may help accurately diagnose SSA/Ps with advanced histology. Removal of SSA/Ps with dysplasia or invasive carcinoma was recommended. Endoscopic treatment such as endoscopic mucosal resection or endoscopic submucosal dissection is useful for those lesions. However, surgical resection with lymph node dissection might be indicated when SSA/Ps with invasive carcinoma are endoscopically suspected, because these have the high risk of lymph node metastasis. Greater awareness may promote further research into improving the detection, recognition, and complete resection rates of SSA/Ps with dysplasia or invasive carcinoma and reduce the interval cancer rates.  相似文献   
70.
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