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   4702篇
  免费   379篇
  国内免费   10篇
耳鼻咽喉   46篇
儿科学   269篇
妇产科学   97篇
基础医学   593篇
口腔科学   83篇
临床医学   479篇
内科学   848篇
皮肤病学   141篇
神经病学   383篇
特种医学   165篇
外科学   430篇
综合类   111篇
一般理论   3篇
预防医学   737篇
眼科学   85篇
药学   373篇
肿瘤学   248篇
  2021年   46篇
  2020年   43篇
  2019年   65篇
  2018年   74篇
  2017年   62篇
  2016年   80篇
  2015年   70篇
  2014年   105篇
  2013年   166篇
  2012年   210篇
  2011年   254篇
  2010年   122篇
  2009年   133篇
  2008年   190篇
  2007年   230篇
  2006年   221篇
  2005年   251篇
  2004年   213篇
  2003年   194篇
  2002年   178篇
  2001年   170篇
  2000年   164篇
  1999年   150篇
  1998年   43篇
  1997年   29篇
  1996年   43篇
  1995年   39篇
  1994年   44篇
  1993年   39篇
  1992年   102篇
  1991年   112篇
  1990年   78篇
  1989年   92篇
  1988年   86篇
  1987年   82篇
  1986年   100篇
  1985年   93篇
  1984年   67篇
  1983年   59篇
  1982年   29篇
  1981年   30篇
  1980年   24篇
  1979年   47篇
  1978年   35篇
  1977年   26篇
  1976年   28篇
  1974年   28篇
  1973年   36篇
  1972年   51篇
  1971年   22篇
排序方式: 共有5091条查询结果,搜索用时 15 毫秒
101.
102.
The substantial morbidity and mortality associated with rheumatoid arthritis (RA), while not widely appreciated, provide adequate justification for consideration of high-dose immunoablative therapy followed by hematopoietic stem cell transplantation. While some patients with RA follow a benign course, selected subsets of patients have been identified with 5-year survival rates of 40-70%. A number of factors that can be easily determined serve as useful prognostic indicators for poor outcome. These include the presence of many involved joints (total joint count), the degree of functional disability as measured by the health assessment questionnaire and the presence of rheumatoid factor. This article summarises the present status of hematopoietic stem cell transplantation for rheumatoid arthritis and proposes future directions for research.  相似文献   
103.
The recent development of several novel approaches for in vivo gene transfer into the coronary arteries and myocardium has led to new possibilities for the treatment of both acquired and inherited cardiovascular diseases. This review summarizes the current state of the art of in vivo gene transfer into the heart and coronary arteries with particular emphasis on antisense oligonucleotide-mediated suppression of gene expression in vascular smooth muscle cells, liposome-mediated gene transfer into the vasculature, and percutaneous transluminal gene transfer (PTGT) into the heart with the use of replication-defective adenoviruses.  相似文献   
104.
Ventricular intramural and epicardial potential distributions were measured during normal excitation and repolarization in intact dogs. Potential distributions were chosen because they can be unambiguously measured, are useful in understanding the shapes of wave forms at many specific sites, and provide a direct measure of repolarization. Unipolar wave forms were recorded from intramural and epicardial electrodes and converted into potential distributions. Well-known shapes of wave forms recorded at the inner and outer layers of the ventricles as well as peak-to-peak voltages were shown by the potential distributions to be determined primarily by superposition effects of distant excitation waves. These effects were most prominent before epicardial breakthrough and then receded during the last half of the QRS complex. However, the potential distributions became more complex as excitation waves merged, collided, and terminated. During terminal depolarization, there were scattered positive repolarization potentials intramurally. Normal repolarization was characterized by positive potentials over the ventricular epicardium while there were changes intramurally and on the atrium. Throughout the T wave, there was a predominant transmural unidirectional gradient with the inner wall being more negative than the outer wall. This finding confirms that the sequence of repolarization is from the epicardium to the endocardium with the middle layers having an intermediate time.  相似文献   
105.
106.
Summary: Immune thrombocytopenia induced by cotrimoxazole. A. L. Barr and M. Whineray. Aust. N.Z. J. Med ., 1980, 10 , pp. 54–55.
Cotrimoxazole administration is occasionally associated with thrombocytopenia. Interference with folate metabolism has been postulated.2 The drug has also been postulated to induce an autoantibody by acting as a hapten3, but proof has not been forthcoming. A case is reported in which the serum has been shown to contain an anti-platelet autoantibody requiring sulphamethoxazole or cotrimoxazole for activity.  相似文献   
107.
This report describes a prospective randomized trial of 503 patients who underwent a cardiac catheterization or interventional procedure at a single institution. In an effort to study femoral complications postprocedure, we evaluated three methods of femoral artery hemostasis as well as 38 variables that were felt to potentially relate to local complications. Only a marginally significant relationship between the hemostasis method and complication rate was found. The factors that contributed to femoral artery complications were: restarting heparin postsheath removal, number of procedures done during one hospitalization, noncompliance of the patient with bedrest after the procedure, number of arterial punctures to initiate the procedure, and preprocedure treatment with corticosteroids.  相似文献   
108.
BACKGROUNDThe significant risks posed to mothers and fetuses by COVID-19 in pregnancy have sparked a worldwide debate surrounding the pros and cons of antenatal SARS-CoV-2 inoculation, as we lack sufficient evidence regarding vaccine effectiveness in pregnant women and their offspring. We aimed to provide substantial evidence for the effect of the BNT162b2 mRNA vaccine versus native infection on maternal humoral, as well as transplacentally acquired fetal immune response, potentially providing newborn protection.METHODSA multicenter study where parturients presenting for delivery were recruited at 8 medical centers across Israel and assigned to 3 study groups: vaccinated (n = 86); PCR-confirmed SARS-CoV-2 infected during pregnancy (n = 65), and unvaccinated noninfected controls (n = 62). Maternal and fetal blood samples were collected from parturients prior to delivery and from the umbilical cord following delivery, respectively. Sera IgG and IgM titers were measured using the Milliplex MAP SARS-CoV-2 Antigen Panel (for S1, S2, RBD, and N).RESULTSThe BNT162b2 mRNA vaccine elicits strong maternal humoral IgG response (anti-S and RBD) that crosses the placenta barrier and approaches maternal titers in the fetus within 15 days following the first dose. Maternal to neonatal anti-COVID-19 antibodies ratio did not differ when comparing sensitization (vaccine vs. infection). IgG transfer ratio at birth was significantly lower for third-trimester as compared with second trimester infection. Lastly, fetal IgM response was detected in 5 neonates, all in the infected group.CONCLUSIONAntenatal BNT162b2 mRNA vaccination induces a robust maternal humoral response that effectively transfers to the fetus, supporting the role of vaccination during pregnancy.FUNDINGIsrael Science Foundation and the Weizmann Institute Fondazione Henry Krenter.  相似文献   
109.

Objectives

To identify the proportion of breast cancer patients that used the Internet for breast cancer information; to classify patterns of use based on patient demographics; and to evaluate whether using the Internet for this purpose was beneficial or problematic. Also to recognize whether a specific demographic group was more likely to experience problems when using the Internet for breast cancer information.

Methods

A 10-item questionnaire was given to patients who attended the breast unit at the University Hospital of South Manchester between May and June 2011 following breast cancer treatment within the last 5 years.

Results

200 questionnaires were completed. 50.5% of patients had used the Internet for breast cancer information, with younger (p < 0.001) patients with a higher household income (p < 0.001) being most likely to do so. The majority (73%) found it beneficial; however 31% had experienced problems. Ethnicity affected the likelihood of experiencing problems with white patients encountering fewer problems (25%) than non-white patients (64%) (p = 0.008).

Conclusion

A significant proportion of breast cancer patients will encounter difficulties when using the Internet for breast cancer information, particularly those from ethnic minorities.

Practice implications

Health professionals need to include a discussion about Internet use in consultations with breast cancer patients.  相似文献   
110.
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