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   6535篇
  免费   713篇
  国内免费   6篇
耳鼻咽喉   163篇
儿科学   419篇
妇产科学   213篇
基础医学   575篇
口腔科学   523篇
临床医学   649篇
内科学   1298篇
皮肤病学   156篇
神经病学   462篇
特种医学   258篇
外科学   1467篇
综合类   33篇
一般理论   1篇
预防医学   268篇
眼科学   179篇
药学   350篇
中国医学   9篇
肿瘤学   231篇
  2023年   139篇
  2022年   71篇
  2021年   214篇
  2020年   173篇
  2019年   204篇
  2018年   421篇
  2017年   324篇
  2016年   409篇
  2015年   403篇
  2014年   418篇
  2013年   817篇
  2012年   357篇
  2011年   351篇
  2010年   417篇
  2009年   220篇
  2008年   119篇
  2007年   54篇
  2006年   205篇
  2005年   144篇
  2004年   67篇
  2003年   62篇
  2002年   84篇
  2001年   139篇
  2000年   107篇
  1999年   132篇
  1998年   132篇
  1997年   102篇
  1996年   132篇
  1995年   83篇
  1994年   93篇
  1993年   80篇
  1992年   57篇
  1991年   58篇
  1990年   44篇
  1989年   25篇
  1988年   33篇
  1987年   15篇
  1986年   24篇
  1985年   21篇
  1984年   27篇
  1983年   21篇
  1982年   26篇
  1981年   26篇
  1980年   22篇
  1979年   19篇
  1978年   10篇
  1977年   10篇
  1976年   12篇
  1974年   11篇
  1947年   7篇
排序方式: 共有7254条查询结果,搜索用时 31 毫秒
81.
82.
Kounis syndrome is a life-threatening medical condition that causes severe allergic reaction and acute coronary syndrome. Benzathine penicillin G is one of the most widely used antibiotics in clinical practice, but it can enhance both allergic and hypersensitivity complications. In this report, we describe the case of a 42-year-old man admitted to our hospital who presented with cryptic tonsillitis accompanied by angioneurotic edema, chest pain, and electrocardiographic variations. The patient was diagnosed with Kounis syndrome and treated with oral antihistamines and prednisolone. He was discharged following a complete recovery and regression of electrocardiographic abnormalities within 72 hours.  相似文献   
83.
Abstract

Synthetic micro/nanomotors (MNMs) are novel, self-propelled nano or microscale devices that are widely used in drug transport, cell stimulation and isolation, bio-imaging, diagnostic and monitoring, sensing, photocatalysis and environmental remediation. Various preparation methods and propulsion mechanisms make MNMs “tailormade” nanosystems for the intended purpose or use. As the one of the newest members of nano carriers, MNMs open a new perspective especially for rapid drug transport and gene delivery. Although there exists limited number of in-vivo studies for drug delivery purposes, existence of in-vitro supportive data strongly encourages researchers to move on in this field and benefit from the manoeuvre capability of these novel systems. In this article, we reviewed the preparation and propulsion mechanisms of nanomotors in various fields with special attention to drug delivery systems.  相似文献   
84.
85.
BackgroundEmerging evidence suggests that sex steroid hormones may influence respiratory symptoms. The existing literature about the role of oral contraceptive pill (OCP) on respiratory disease is scarce and conflicting especially during the adolescent period. In this study, we aimed to investigate the effect of OCPs on current wheezing among adolescents and young adults.MethodsA questionnaire was administered face-to-face to adolescents and young women by a physician. The questionnaire included ISAAC survey-comprised questions on ever wheezing, current wheezing, allergic diseases, smoking history (active or passive), and family history of allergic diseases and questions on OCP usage status. The effect of OCPs on wheezing was evaluated by logistic regression analysis.ResultsA total of 487 subjects aged between 11.3 and 25.6 years participated in the study and 196 (40.2%) reported that they had used OCPs. 7.4% of the participants had physician-diagnosed asthma and 10.3% of them were active smokers. It was detected that OCPs were associated with increased risk for current wheezing (odds ratio, 2.36; 95% CI, 1.25–4.47 adjusted for asthma and current smoker) and this risk was related with the usage during the past year.ConclusionYoung women taking oral contraceptives had a higher rate of current wheezing, suggesting that sex steroids may be of importance for respiratory health.  相似文献   
86.
87.
88.
89.
90.
Purpose: The aim of the study was to investigate whether maternal serum TSP-1 level was associated with PE.

Materials and methods: In our case control study, 84 pregnant women in the third trimester were included. Forty-one of them were healthy and 43 of them were with the diagnosis of PE. The diagnosis was based on the definitions of the National High Blood Pressure Education Program working Group on High Blood Pressure in Pregnancy. Preeclamptic patients were divided into two subgroups as mild and severe. Blood pressure (BP) of pregnant women were obtained in left-side lying position using a mercury sphygmomanometer after at least 10 minutes of rest. Ten milliliters of venous blood was taken from every pregnant women and dispensed into lithium heparin and serum was obtained. Samples were stored at ?80?°C until analyzed. Serum TSP-1 level was measured using enzyme-linked immunosorbent assay (ELISA). All tests were two-tailed and p < .05 was considered to be statistically significant.

Results: TSP-1 level was significantly lower in PE group than in controls (p?=?.003). Platelet counts were similar in two groups (p = .26). TSP-1 levels were significantly lower in severe PE than in mild PE cases. According to the subgroup analysis, TSP-1 level was found significantly lower in severe preeclampsia group compared to control group (p = .015).

Conclusions: In light of the association between endothelial dysfunction and preeclampsia, we claim that lower levels of TSP-1 which is released mostly from endothelial cells seem to reflect disease severity in PE. Our study reveals that maternal serum TSP-1 levels decrease in pregnant women presenting with PE and TSP-1 may be a new biomarker for the detection of PE and even severity of it. Further studies especially prospective ones with greater numbers of cases are needed.  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