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   20213篇
  免费   1390篇
  国内免费   38篇
耳鼻咽喉   123篇
儿科学   599篇
妇产科学   441篇
基础医学   2430篇
口腔科学   459篇
临床医学   3199篇
内科学   3281篇
皮肤病学   208篇
神经病学   1932篇
特种医学   541篇
外科学   2025篇
综合类   719篇
一般理论   36篇
预防医学   2430篇
眼科学   438篇
药学   1449篇
  2篇
中国医学   10篇
肿瘤学   1319篇
  2023年   100篇
  2022年   188篇
  2021年   375篇
  2020年   232篇
  2019年   362篇
  2018年   457篇
  2017年   331篇
  2016年   361篇
  2015年   394篇
  2014年   538篇
  2013年   914篇
  2012年   1349篇
  2011年   1551篇
  2010年   809篇
  2009年   755篇
  2008年   1361篇
  2007年   1450篇
  2006年   1450篇
  2005年   1437篇
  2004年   1469篇
  2003年   1407篇
  2002年   1232篇
  2001年   257篇
  2000年   174篇
  1999年   202篇
  1998年   249篇
  1997年   184篇
  1996年   137篇
  1995年   145篇
  1994年   111篇
  1993年   123篇
  1992年   124篇
  1991年   89篇
  1990年   97篇
  1989年   81篇
  1988年   72篇
  1987年   73篇
  1986年   95篇
  1985年   72篇
  1984年   78篇
  1983年   78篇
  1982年   61篇
  1981年   66篇
  1980年   78篇
  1979年   45篇
  1978年   50篇
  1977年   38篇
  1976年   34篇
  1975年   34篇
  1973年   38篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
The anti-granulocyte activity of serum from patients with B-cell chronic lymphocytic leukaemia (CLL) and other lymphoproliferative disorders was investigated. Granulocyte-binding IgG was measured in 34 patients with CLL, 13 patients with hairy cell leukaemia, one patient with prolymphocytic leukaemia, two patients with Sézary cell leukaemia, and seven patients with chronic T-cell lymphocytosis who had a predominance of circulating large granular lymphocytes. Anti-granulocyte activity was absent in CLL and its variants, but present in the majority of granulocytopenic patients with chronic T-cell lymphocytosis. In one of these patients, granulocytopenia was associated with complement-activating IgG granulocyte antibody. Thus, antibody-mediated granulocyte injury appears to be an unusual occurrence in chronic lymphocytic leukaemia, but is a frequent complication of chronic T-cell lymphocytosis.  相似文献   
12.
Abstract:  The risks of developing malignant melanoma (MM) include ultraviolet irradiation and genetic factors. To examine the contribution of rare and common variation within known MM genes in sporadic US MM patients, coding regions of known MM susceptibility genes [cyclin-dependent kinase inhibitor 2A ( CDKN2A ), cyclin-dependent kinase 4, melanocortin 1 receptor ( MC1R ) and tyrosinase ( TYR )] were resequenced in 109–135 MM cases. The significance of variants was examined by comparing their frequencies in 390 cancer-free controls. Potential deleterious mutations in CDKN2A were found in two patients and two others had variants of unknown significance. Cases were more likely than controls to harbour the MC1R 'R' variants known or predicted to alter its function ( P  = 0.002), particularly the R160W variant ( P  = 0.0035). The associated TYR R402Q variant (rs1126809*A) was found in 29% of cases, similar to what has been described previously. One MM patient with a family history of MM, who had developed other skin cancers, was homozygous for a novel TYR variant (P406L) of unknown significance. Hence, rare variants in TYR may be important risk factors for skin cancer.  相似文献   
13.
Objective To assess the availability of resources that support the provision of basic neonatal care in eight first‐referral level (district) hospitals in Kenya. Methods We selected two hospitals each from four of Kenya’s eight provinces with the aim of representing the diversity of this part of the health system in Kenya. We created a checklist of 53 indicator items necessary for providing essential basic care to newborns and assessed their availability at each of the eight hospitals by direct observation, and then compared our observations with the opinions of health workers providing care to newborns on recent availability for some items, using a self‐administered structured questionnaire. Results The hospitals surveyed were often unable to maintain a safe hygienic environment for patients and health care workers; staffing was insufficient and sometimes poorly organised to support the provision of care; some key equipment, laboratory tests, drugs and consumables were not available while patient management guidelines were missing in all sites. Conclusion Hospitals appear relatively poorly prepared to fill their proposed role in ensuring newborn survival. More effective interventions are needed to improve them to meet the special needs of this at‐risk group.  相似文献   
14.
15.
A peculiarly effective intervention by the author's psychoanalyst is explored and discussed in terms of its implicitly expressive properties. It is placed in the context of the classical concept of opacity and more flexible Sullivanian ideas, as expanded and clarified by Havens.  相似文献   
16.
17.
18.
Popliteal artery aneurysms representing 80% of peripheral artery aneurysms rarely rupture (a reported incidence of 0.1–2.8 %) and second commonest in frequency after aorto-iliac aneurysms. They usually present with pain, swelling, occlusion or distal embolisation and can cause diagnostic difficulties. We report a 78 year old man who was previously admitted to hospital with a pulmonary embolus secondary to deep venous thrombosis. He was heparinized then warfarinised and was readmitted with a ruptured popliteal aneurysm leading to a large pseudo aneurysm formation. The pulmonary embolus had been due to popliteal vein thrombosis and propagation of the clot. A thorough review of literature identified only one previously reported case of ruptured popliteal artery aneurysm and subsequent large pseudo aneurysm formation. We feel it is important to exclude a popliteal aneurysm in a patient with DVT. This may be more common than the published literature suggests.  相似文献   
19.
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