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   701篇
  免费   82篇
  国内免费   4篇
耳鼻咽喉   3篇
儿科学   45篇
妇产科学   126篇
基础医学   103篇
口腔科学   4篇
临床医学   52篇
内科学   181篇
皮肤病学   6篇
神经病学   54篇
特种医学   3篇
外科学   74篇
综合类   8篇
预防医学   35篇
眼科学   1篇
药学   55篇
中国医学   1篇
肿瘤学   36篇
  2021年   8篇
  2020年   6篇
  2019年   8篇
  2018年   8篇
  2017年   8篇
  2016年   11篇
  2015年   7篇
  2014年   11篇
  2013年   20篇
  2012年   30篇
  2011年   29篇
  2010年   16篇
  2009年   33篇
  2008年   25篇
  2007年   36篇
  2006年   24篇
  2005年   27篇
  2004年   24篇
  2003年   25篇
  2002年   30篇
  2001年   28篇
  2000年   16篇
  1999年   30篇
  1998年   11篇
  1997年   10篇
  1996年   10篇
  1995年   15篇
  1994年   7篇
  1993年   9篇
  1992年   28篇
  1991年   15篇
  1990年   18篇
  1989年   14篇
  1988年   11篇
  1987年   15篇
  1986年   13篇
  1985年   10篇
  1984年   9篇
  1983年   16篇
  1982年   12篇
  1980年   9篇
  1979年   18篇
  1978年   13篇
  1977年   6篇
  1976年   9篇
  1975年   13篇
  1974年   4篇
  1973年   4篇
  1972年   4篇
  1967年   5篇
排序方式: 共有787条查询结果,搜索用时 62 毫秒
11.
12.
Focal pulmonary alveolar proteinosis in pulmonary tuberculosis   总被引:1,自引:0,他引:1  
  相似文献   
13.
Japanese men long resident in Honolulu, Hawaii have significantly more ischemic heart disease but significantly fewer small cardiac scars than men in Hiroshima, Japan. These scars occur in three forms:(1)small scars in the mural myocardium which account for the difference in frequency of small lesions in the two cities and are of uncertain etiology; (2)areas of diffuse fibrosis in the papillary muscles. These are equally frequent in the two cities and are associated with advancing age and sclerosis of papillary muscle arteries; and(3)focal scars in the papillary muscles. These are more frequent in Honolulu than Hiroshima. They are healed infarcts due to ischemic heart disease and are associated with a severe degree of extramural coronary artery atherosclerosis. Small mural myocardial scars, when present, are usually found in multiple sites. Their increased frequency in Hiroshima is not explained by differences in age or heart weight. They are more common in the presence of sclerosis of intramural small arteries, but this association also fails to explain the intercity difference. It is supected that the excess of these small cardiac scars in Hiroshima males reflects past privation. There is no evidence that is is related to A-bomb radiation exposure.  相似文献   
14.
Tissue macrophages, which participate in chronic synovial inflammation, differentiate from haemopoietic precursors in bone marrow and subsequently in tissue. During this process, they acquire attributes which are essential for their function in inflammation. Modulation of this process may represent a means of regulating inflammatory competence of macrophages in inflammatory joint disease. The action of aurothiomalate (ATM), an anti-rheumatic gold compound, on the differentiation of a promonocytic cell line (U937) was, therefore, examined inin vitro systems. U937 cells exposed to retinoic acid (RA) for 4 days or to phorbol myristate acetate (PMA) for 2 days acquired characteristics of macrophages, including the capacity to produce superoxide (O 2 ), responsiveness to formyl-methionyl-leucyl-phenylalanine (fMLP) and reduced proliferation. The activity of transglutaminase also increased in RA-exposed cultures. The effect of ATM exposure on acquisition of these characteristics was small and differed between RA- and PMA-stimulated cells.  相似文献   
15.
In order to achieve a clinical pregnancy rate higher than that achieved following initial adoption of in-vitro fertilization embryo transfers, more than one embryo is transferred. This has led to a substantial increase in unwanted multiple pregnancy rates with IVF as compared with natural conception. What is therefore required is a simple, clinically useful embryo scoring system, to reflect embryo developmental potential, which will enable the selection of the optimal number of embryos to transfer in order to achieve the maximum pregnancy rate with a low incidence of high order multiple pregnancies. We believe that the Cumulative Embryo Score (CES) achieves these aims. On the day of embryo transfer the grade of each embryo transferred was multiplied by the number of blastomeres to produce a score for each embryo, and summation of the scores obtained for all the embryos transferred gave the CES. The grouped pregnancy rates obtained rose as the CES increased to maximum of 42. A continued increase in the CES above 42 did not result in any further rise in the pregnancy rate. However, an analysis of all our IVF pregnancies showed that the multiple pregnancy rate continued to rise above a CES of 42. By restricting the CES per embryo transfer to 42, 78% of triplet pregnancies and 100% of the quadruplet IVF pregnancies could have been predicted and potentially avoided.  相似文献   
16.
We report a case in which thrombelastography (TEG) and Sonoclot analysis were used for diagnosis and treatment decisions in a patient with abruptio placentae and disseminated intravascular coagulation. In addition to providing enough information for evaluation and treatment of this patient, the TEG and Sonoclot results were obtained more quickly, with smaller blood samples and with less expense to the patient in comparison to the standard coagulation tests in our institution. Although the TEG and Sonoclot results were assessed independently of the other test and each provided similar information in this case, the TEG may be the preferred tool in evaluating coagulopathies, based on computerization and strong literature support.  相似文献   
17.
To ascertain how effective the Beck Depression Inventory for Primary Care (BDI-PC) was in screening for DSM-IV major depression disorders (MDD) in outpatients who were scheduled for routine office visits with physicians specializing in internal medicine, the BDI-PC was administered to 60 male and 60 female outpatients. The internal consistency of the BDI-PC was high (alpha 0.85), and the Mood Module from the Primary Care Evaluation of Mental Disorders was used to diagnose MDD. The BDI-PC scores were not significantly correlated with sex, age, ethnicity, or total number of medical diagnoses. A BDI-PC cutoff score of 4 and above yielded 98% maximum clinical efficiency with 97% (95% CI 82%-99%) sensitivity and 99% (95% CI 94%-99%) specificity rates, respectively, for identifying patients with and without MDD. The BDI-PC is discussed as an effective case-finding instrument for screening primary care patients for MDD.  相似文献   
18.
19.
The major burden of preterm birth is in the developing world, where most of the increasing death and morbidity is secondary to infectious diseases such as malaria, HIV, tuberculosis, bacterial vaginosis and intestinal parasites. In some developing countries, the growth of medical care has outstripped the growth of preventive public health, with an associated increase in iatrogenic preterm births. In developed countries, more than one-third of preterm births are medically indicated because of conditions such as fulminating pre-eclampsia or severe intrauterine growth restriction. Neither of these conditions is currently preventable. One in five preterm births is associated with multiple pregnancy, and these have been greatly increased by assisted reproduction techniques. The use of tocolytics has proved disappointing perhaps because inflammation rather than spontaneous uterine activity is increasingly recognised as the final common pathway. Inappropriate antibiotics used late in pregnancy are ineffective and may have adverse effects. Currently, the most promising interventions are public health related and include reducing the transmission of communicable diseases, improvements in the management of diabetes and reduction in harmful behaviours such as smoking and drug abuse.  相似文献   
20.
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