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   1829231篇
  免费   137071篇
  国内免费   12910篇
耳鼻咽喉   22749篇
儿科学   57602篇
妇产科学   47592篇
基础医学   253631篇
口腔科学   51300篇
临床医学   170450篇
内科学   349423篇
皮肤病学   40246篇
神经病学   135924篇
特种医学   68430篇
外国民族医学   286篇
外科学   267445篇
综合类   68106篇
现状与发展   44篇
一般理论   541篇
预防医学   137260篇
眼科学   43841篇
药学   139024篇
  243篇
中国医学   15227篇
肿瘤学   109848篇
  2021年   19298篇
  2020年   13391篇
  2019年   17544篇
  2018年   23991篇
  2017年   19719篇
  2016年   20395篇
  2015年   25239篇
  2014年   33938篇
  2013年   45936篇
  2012年   64601篇
  2011年   67988篇
  2010年   42462篇
  2009年   38712篇
  2008年   60352篇
  2007年   63331篇
  2006年   62817篇
  2005年   59271篇
  2004年   55271篇
  2003年   52363篇
  2002年   49816篇
  2001年   94285篇
  2000年   95672篇
  1999年   78550篇
  1998年   20681篇
  1997年   18269篇
  1996年   18145篇
  1995年   17395篇
  1994年   15880篇
  1993年   14425篇
  1992年   57686篇
  1991年   55549篇
  1990年   53223篇
  1989年   50946篇
  1988年   46321篇
  1987年   45093篇
  1986年   42327篇
  1985年   40064篇
  1984年   29406篇
  1983年   24964篇
  1982年   13934篇
  1979年   25544篇
  1978年   17591篇
  1977年   14925篇
  1976年   13892篇
  1975年   14580篇
  1974年   17647篇
  1973年   16960篇
  1972年   15688篇
  1971年   14461篇
  1970年   13436篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
The treatment of genito-urinary tuberculosis with streptomycin alone   总被引:1,自引:0,他引:1  
  相似文献   
932.
933.
SMYTH FS  BOWEN 《Pediatrics》1948,2(1):119-131
  相似文献   
934.
Osteochondromatosis   总被引:5,自引:0,他引:5  
  相似文献   
935.
936.
937.
OBJECTIVES: Local anaesthetic infiltration into the carotid sinus during carotid endarterectomy (CEA) has been recommended to minimise blood pressure fluctuations but its use remains controversial. The aim of this meta-analysis was to determine whether intra-operative administration of local anaesthetic reduces the incidence of haemodynamic instability following CEA. MATERIALS AND METHODS: A search of the Medline, Pubmed and Embase databases and the Current Controlled Trials register identified four trials, which met the pre-defined inclusion criteria for data extraction. Pooled odds ratios with 95 per cent confidence intervals (c.i.) for the development of post-operative hypotension and hypertension were calculated using a random-effects model. RESULTS: Outcomes of 432 patients were studied. Local anaesthetic blockade of the carotid sinus was associated with a pooled odds ratio of 1.25 (95 per cent c.i. 0.496 to 3.15); p=0.216) and 1.28 (95 per cent c.i. 0.699 to 2.33; p=0.428) for the development of post-operative hypotension and hypertension respectively. Although none reach significance there was a trend towards increased risk of developing a complication in those patients who received local anaesthetic. CONCLUSIONS: There are insufficient data to determine the role of intra-operative local anaesthetic administration in reducing post-operative blood pressure lability following CEA. Conversely, the possibility of harm cannot be excluded on the basis of the currently available data.  相似文献   
938.
939.
Human leukocyte antigen (HLA) compatibility has no clinically significant impact in cadaveric liver transplantation. Less is known regarding living-donor liver transplantation (LDLT). Our prior analysis of the Organ Procurement and Transplantation Network (OPTN) database suggested a higher graft failure rate in patients who underwent LDLT from donors with close HLA match. We further investigated the effect of HLA-A, -B, and -DR matching on 5-yr graft survival in adult LDLT by analyzing OPTN data regarding adult LDLT performed between 1998 and 2005. We evaluated associations between 5-yr graft survival and total, locus-specific, and haplotype match levels. Separate analyses were conducted for recipients with autoimmune (fulminant autoimmune hepatitis, cirrhosis secondary to autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis) or nonautoimmune liver disease. Multivariable Cox proportional hazard models were used to evaluate interactions and adjust for potential confounders. Among 631 patients with available donor/recipient HLA data, the degree of HLA match had no significant effect on 5-yr graft survival, even when analyzed separately in recipients with autoimmune vs. nonautoimmune liver disease. To be able to include all 1,838 adult LDLTs, we considered a first-degree related donor as substitute for a close HLA match. We found no difference in graft survival in related vs. unrelated pairs. In conclusion, our results show no detrimental impact of close HLA matching on graft survival in adult LDLT, including in recipients with underlying autoimmune liver disease.  相似文献   
940.
Klippel-Feil syndrome (KFS) is a heterogeneous entity, characterized by specific congenital anomalies of segmentation of the cervical spine. We report a case of KFS plus atretic meningocele in one identical twin and anencephaly in the other. These identical twins were both male with no chromosome defect. One of them had anencephaly diagnosed at the gestational age of 17 weeks and died soon after birth, whereas the co-twin had KFS with multiple congenital anomalies including short neck with low hairline, occipital atretic meningocele, butterfly vertebrae, hemivertebrae, cervico-thoracic scoliosis, left thumb preaxial polydactyly, and right undescended testis. He received rehabilitation during infancy and could walk at the age of 15 months. Both of these infants had preaxial polydactyly, which is an uncommon anomaly associated with KFS. In conclusion, iniencephaly and anencephaly are probably the extreme manifestations of KFS rather than different dysraphisms. Prompt clinical suspicion with early diagnostic imaging for spine lesions and occult opening of neural tube is mandatory for further intervention and rehabilitation.  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