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   1280628篇
  免费   97891篇
  国内免费   1998篇
耳鼻咽喉   18449篇
儿科学   44411篇
妇产科学   35043篇
基础医学   182392篇
口腔科学   33637篇
临床医学   111407篇
内科学   258551篇
皮肤病学   28036篇
神经病学   100560篇
特种医学   51292篇
外国民族医学   660篇
外科学   196623篇
综合类   27063篇
现状与发展   1篇
一般理论   380篇
预防医学   95849篇
眼科学   27917篇
药学   94891篇
  2篇
中国医学   2422篇
肿瘤学   70931篇
  2018年   13147篇
  2017年   9988篇
  2016年   10926篇
  2015年   12402篇
  2014年   17208篇
  2013年   26280篇
  2012年   36088篇
  2011年   38145篇
  2010年   22847篇
  2009年   21855篇
  2008年   36706篇
  2007年   39323篇
  2006年   39574篇
  2005年   38523篇
  2004年   37683篇
  2003年   36522篇
  2002年   35869篇
  2001年   64042篇
  2000年   66555篇
  1999年   56471篇
  1998年   15156篇
  1997年   13766篇
  1996年   14204篇
  1995年   13471篇
  1994年   12788篇
  1993年   11803篇
  1992年   44592篇
  1991年   43501篇
  1990年   42252篇
  1989年   40137篇
  1988年   36924篇
  1987年   36264篇
  1986年   33668篇
  1985年   32314篇
  1984年   24155篇
  1983年   20295篇
  1982年   11733篇
  1981年   10707篇
  1980年   9521篇
  1979年   21368篇
  1978年   14843篇
  1977年   12547篇
  1976年   11703篇
  1975年   12642篇
  1974年   14670篇
  1973年   14125篇
  1972年   12963篇
  1971年   11737篇
  1970年   11061篇
  1969年   10041篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved.  相似文献   
962.
In a study of 66 patients with systemic lupus erythematosus (SLE) and 80 controls it was found that the presence of two deficiency (null) alleles of C4 had a significant effect on mean C4 concentrations in serum. In six controls who each had two C4 null alleles the mean C4 concentration in serum was 56% lower than in 43 controls without C4 null alleles; the nadir of the C4 concentration in four patients with SLE with two null alleles was also lower by a mean of 55% than in 32 patients who did not have null alleles. Reduced production of C4 allotypes in subjects with two null alleles may be an important determinant of total C4 concentration in patients with SLE. For optimal interpretation of C4 concentrations in SLE, C4 allotyping appears to be indicated, particularly to identify patients who have two null alleles of C4.  相似文献   
963.
964.
965.
Plasma D-dimer (DD) and thrombin--antithrombin III complex (TAT) were measured with ELISAs in 99 patients investigated by 102 ventilation--perfusion lung scintigraphy because of suspected pulmonary embolism. High-probability lung scan was associated with increased DD (more than 500 ng/ml) and TAT (more than 4.1 ng/ml) levels (sensitivity of 100 and 70%, respectively). The corresponding figures of specificity were 81 and 42%. In the 56 patients with low-probability or indeterminate probability scans, 31 (55%) had DD concentrations of less than 500 ng/ml. These preliminary data suggest that a plasma DD concentration of less than 500 ng/ml might rule out the diagnosis of pulmonary embolism in suspected patients with an inconclusive lung scanning.  相似文献   
966.
J N Harvey  M E Denyer    P DaCosta 《Gut》1989,30(5):691-694
We describe a patient with extensive ischaemic necrosis of the ileum as a result of elastic vascular sclerosis (EVS). A 2 cm carcinoid tumour was located nearby with microscopic evidence of spread to regional lymph nodes. Severe intestinal ischaemia caused by carcinoid associated EVS may be the presenting feature of small carcinoid tumours resulting in their early diagnosis.  相似文献   
967.
968.
969.
Patients suffering from pain due to osteoarthritis of the hip and knee participated in a double-blind placebo controlled trial using daily Codetron home care units for 6 weeks over the tibial, saphenous, popliteal and sciatic nerves, and tender points. Seventy-four percent of patients in the real Codetron (Group A) and 28% of the patients in sham Codetron (Group B) improved their pain level more than 25% as measured by visual analogue scale. The difference in pain improvement in the two groups was statistically significant (p less than 0.02 using Fisher's exact probability ratio). Other functional parameters proved to be insensitive to change in this study. This is highly suggestive of beneficial effect of nonhabituating Codetron as a complementary modality in the therapy of chronic pain conditions such as osteoarthritis.  相似文献   
970.
Sexual victimization is a singularly traumatic event. At times, however, the implicit danger of the trauma experience itself gets exaggerated. For the victim the more lasting damage frequently stems from how he or she was treated by friends, family, health care providers, and public authorities following the incident. Treating the victimized patient as quickly and sensitively as possible is essential to minimizing the potential for further victimization. The Emergency Department at Boston City Hospital is frequently the site for the acute management of sexual assault victims. The Victim Care Service is designed to prevent secondary traumatization of such victims. The five-phase program and the fundamental assumptions upon which the phases are based are presented.  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