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   1079938篇
  免费   72161篇
  国内免费   1502篇
耳鼻咽喉   15143篇
儿科学   34805篇
妇产科学   28695篇
基础医学   153936篇
口腔科学   29749篇
临床医学   95398篇
内科学   204617篇
皮肤病学   24502篇
神经病学   81788篇
特种医学   43164篇
外国民族医学   203篇
外科学   163887篇
综合类   22157篇
现状与发展   2篇
一般理论   264篇
预防医学   74919篇
眼科学   24637篇
药学   86497篇
  11篇
中国医学   2962篇
肿瘤学   66265篇
  2019年   7902篇
  2018年   11439篇
  2017年   9047篇
  2016年   10242篇
  2015年   11434篇
  2014年   15519篇
  2013年   22487篇
  2012年   30846篇
  2011年   32553篇
  2010年   19103篇
  2009年   17949篇
  2008年   30128篇
  2007年   32289篇
  2006年   32913篇
  2005年   31232篇
  2004年   30049篇
  2003年   28911篇
  2002年   27805篇
  2001年   60262篇
  2000年   61646篇
  1999年   51042篇
  1998年   12508篇
  1997年   11049篇
  1996年   11045篇
  1995年   10342篇
  1994年   9358篇
  1993年   8876篇
  1992年   37817篇
  1991年   36290篇
  1990年   35757篇
  1989年   34307篇
  1988年   30888篇
  1987年   30002篇
  1986年   28240篇
  1985年   26458篇
  1984年   19198篇
  1983年   16123篇
  1982年   8830篇
  1979年   17039篇
  1978年   11412篇
  1977年   10234篇
  1976年   8840篇
  1975年   10073篇
  1974年   11658篇
  1973年   11277篇
  1972年   10763篇
  1971年   10096篇
  1970年   9254篇
  1969年   8942篇
  1968年   7919篇
排序方式: 共有10000条查询结果,搜索用时 2 毫秒
111.
The amount of endothelial cell loss that occurs to the donor cornea during the trephination process was evaluated in 40 porcine eyes. A vital staining technique (alizarin red S and acid violet 19) was used to quantify the extent of endothelial damage and removal. Two types of corneal punches (Weck and H&I0 were used for trephination. The average amount of endothelial loss from the peripheral cornea was 7.9%, accounting for only a 3% loss of endothelial cells over the total surface area of the corneal button. a comparison of the Weck and H&I corneal punches showed no significant difference (P greater than 0.1) by Student's test for both endothelial cell damage and removal.  相似文献   
112.
Multicentricity of hepatocellular carcinoma (HCC) is considered, especially in patients with liver cirrhosis. This paper describes an operative case of a male patient with probable multicentric development of HCC in precirrhotic fibrosis. The main tumors inside the capsule were completely necrotic due to transarterial embolization (TAE). Histologic examination disclosed discrete tiny nodules of HCC that were not detected grossly. They showed highly differentiated trabecular arrangements: Edmondson I. A scirrhous type was noted in the center of the tumors. At the borders of the tumors the carcinoma cells exhibited replacing growth patterns and it was thought that they developed multicentrically. Partial resection must be performed as extensively as possible in a case such as the present one.  相似文献   
113.
The effect of psychosocial factors on lung cancer mortality at one year   总被引:1,自引:0,他引:1  
In this study newly diagnosed male and female lung cancer patients admitted to two Ontario Cancer Foundation treatment clinics were interviewed. Information was obtained on demographic variables, presence of other chronic illness and the following psychosocial attributes: locus of control, social support and personality traits. From the clinic charts, information on stage of disease and pathological diagnosis was obtained. After controlling for the effects of stage and pathological diagnosis, the following psychological variables were found to increase the odds of death from lung cancer among males and females combined at one year after diagnosis: a high need for one aspect of social support, a reserved personality and the extremes of the personality trait soberness vs enthusiasm.  相似文献   
114.
Recently, we demonstrated that spaghetti caused significantly lower glycaemic response than rice and potato in insulin-dependent diabetic (IDDM) subjects and that this difference was also present when spaghetti and potato were taken as part of a mixed meal. We have now compared the blood glucose and insulin responses to 50 g of carbohydrate in the form of white bread, potato and white spaghetti in 6 non-insulin-dependent diabetic (NIDDM) patients. The blood glucose response after white spaghetti observed over a 3-h period was only 60 +/- 10 per cent (P less than 0.02) of that seen in response to potato (395 +/- 116 mmol/l x 180 min vs 641 +/- 108 mmol/l x 180 min) and 47 +/- 9 per cent (P less than 0.01) of that seen in response to white bread (395 +/- 116 mmol/l x 180 min vs 805 +/- 93 mmol/l x 180 min). Insulin responses showed an identical pattern reflecting the glycaemic responses. To see if the difference in the glucose responses in NIDDM patients is preserved if these carbohydrate-rich foods are taken as part of a mixed meal we looked at the blood glucose and insulin responses to 50 g of carbohydrate in the form of potato and white spaghetti when ingested together with bolognese sauce (167 g) in 7 NIDDM patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
115.
116.
117.
118.
Previously, we prepared two different monoclonal antibodies (mAbs) against human 4-1BB (CD137): an agonistic mAb BBK-1 and an antagonistic mAb BBK-2. In this paper, we describe the molecular cloning of these two mAbs and present comparisons of their amino acid sequences. cDNAs encoding the heavy (H) and light (L) chains of the two mAbs were cloned by screening of cDNA libraries constructed from hybridomas secreting these mAbs. Comparisons of amino acid sequences of the two mAbs showed that, while the constant regions of the H and L chains were identical between the two mAbs, the variable region showed 45% identity in H chains and 48% identity in L chains. This suggests that these two mAbs recognize different epitopes of 4-1BB and may have different effects on the activity of 4-1BB.  相似文献   
119.
Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst...  相似文献   
120.
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