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   538361篇
  免费   28798篇
  国内免费   515篇
耳鼻咽喉   6783篇
儿科学   17465篇
妇产科学   12747篇
基础医学   94003篇
口腔科学   12438篇
临床医学   48952篇
内科学   96991篇
皮肤病学   12092篇
神经病学   34488篇
特种医学   20064篇
外国民族医学   54篇
外科学   79056篇
综合类   8038篇
现状与发展   2篇
一般理论   113篇
预防医学   39109篇
眼科学   12276篇
药学   42269篇
  1篇
中国医学   1201篇
肿瘤学   29532篇
  2021年   4209篇
  2019年   4082篇
  2018年   6003篇
  2017年   4317篇
  2016年   5107篇
  2015年   5623篇
  2014年   7480篇
  2013年   10961篇
  2012年   16193篇
  2011年   18068篇
  2010年   10337篇
  2009年   9146篇
  2008年   16208篇
  2007年   18005篇
  2006年   17465篇
  2005年   16704篇
  2004年   16281篇
  2003年   15628篇
  2002年   15122篇
  2001年   22680篇
  2000年   23214篇
  1999年   19116篇
  1998年   5311篇
  1997年   4427篇
  1996年   4459篇
  1995年   4172篇
  1992年   14547篇
  1991年   15951篇
  1990年   16050篇
  1989年   15725篇
  1988年   14431篇
  1987年   14289篇
  1986年   13270篇
  1985年   12790篇
  1984年   9474篇
  1983年   8047篇
  1982年   4210篇
  1979年   8992篇
  1978年   6423篇
  1977年   5180篇
  1976年   5543篇
  1975年   6647篇
  1974年   7466篇
  1973年   7211篇
  1972年   6635篇
  1971年   6361篇
  1970年   5938篇
  1969年   5496篇
  1968年   5177篇
  1967年   4642篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Treatment guidelines for management of uncomplicated gonorrhoeae have been recently modified owing to alarming upsurge in azithromycin resistance. This study investigated the prevalence and genetic determinants of gonococcal azithromycin resistance in India. Four (5.7%) of 70 gonococcal isolates were resistant to azithromycin. Of 16 isolates investigated for molecular mechanisms of resistance, 13 (81.3%) and 6 (37.5%) isolates exhibited mutations in coding and promoter regions of mtrR gene, respectively. However, ermA, ermB and ermC genes or mutations in rrl gene were absent in all isolates. Azithromycin resistance is low in India posing no immediate threat to use of dual-therapy for syndromic management.  相似文献   
2.
Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses...  相似文献   
3.
The adrenal cortex gives rise to a biologically heterogenous group of neoplasms, each with a distinct morphology, antigen expression and molecular profile. Adrenal cortical adenomas have excellent prognosis and are usually cured by surgical resection alone, while adrenal cortical carcinomas are very aggressive tumors with a poor prognosis regardless of therapy. These tumors are rare and often challenging for a pathologist to diagnose, as significant overlap exists between benign and malignant lesions in some cases. In this review, we attempt to summarize most important histologic and clinical features of adrenal cortical adenomas and carcinomas, clarify the use of different grading systems, the use of special stains and the differential diagnosis for practicing pathologists. Most relevant hereditary syndromes associated with adrenal cortical tumors are listed. Updates in molecular alterations in adrenal cortical neoplasms and hyperplastic diseases as well as their clinical significance and potential therapeutic implications are also discussed.  相似文献   
4.
5.
6.
Journal of Immigrant and Minority Health - COVID-19 has disproportionally affected underrepresented minorities (URM) and low-income immigrants in the United States. The aim of the study is to...  相似文献   
7.
Microbial co-infections are another primary concern in patients with coronavirus disease 2019 (COVID-19), yet it is an untouched area among researchers. Preliminary data and systematic reviews only show the type of pathogens responsible for that, but its pathophysiology is still unknown. Studies show that these microbial co-infections are hospital-acquired/nosocomial infections, and patients admitted to intensive care units with invasive mechanical ventilation are highly susceptible to it. Patients with COVID-19 had elevated inflammatory cytokines and a weakened cell-mediated immune response, with lower CD4+ T and CD8+ T cell counts, indicating vulnerability to various co-infections. Despite this, there are only a few studies that recommend the management of co-infections.  相似文献   
8.
9.
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was...  相似文献   
10.
Bulletin of Experimental Biology and Medicine - Ammonium, an end-product of catabolism, in low doses can promote adaptation of metabolic pathways in erythrocytes under conditions of extreme...  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