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   15943篇
  免费   1029篇
  国内免费   57篇
耳鼻咽喉   330篇
儿科学   436篇
妇产科学   236篇
基础医学   2130篇
口腔科学   416篇
临床医学   1312篇
内科学   3269篇
皮肤病学   351篇
神经病学   1308篇
特种医学   1060篇
外国民族医学   10篇
外科学   2497篇
综合类   118篇
一般理论   2篇
预防医学   1070篇
眼科学   282篇
药学   1075篇
中国医学   22篇
肿瘤学   1105篇
  2021年   240篇
  2020年   140篇
  2019年   194篇
  2018年   256篇
  2017年   216篇
  2016年   281篇
  2015年   302篇
  2014年   362篇
  2013年   447篇
  2012年   710篇
  2011年   712篇
  2010年   389篇
  2009年   405篇
  2008年   701篇
  2007年   700篇
  2006年   703篇
  2005年   730篇
  2004年   669篇
  2003年   658篇
  2002年   636篇
  2001年   611篇
  2000年   603篇
  1999年   521篇
  1998年   221篇
  1997年   190篇
  1996年   170篇
  1995年   139篇
  1994年   140篇
  1993年   134篇
  1992年   328篇
  1991年   303篇
  1990年   325篇
  1989年   318篇
  1988年   271篇
  1987年   257篇
  1986年   242篇
  1985年   231篇
  1984年   194篇
  1983年   161篇
  1982年   114篇
  1981年   94篇
  1979年   155篇
  1978年   117篇
  1977年   92篇
  1976年   91篇
  1975年   110篇
  1974年   104篇
  1973年   100篇
  1970年   96篇
  1969年   94篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
Seventy-six patients with severely comminuted distal radial fractures were treated at two institutions, of which the overwhelming majority were Frykman class VIII. Fifteen fractures were open. Thirty patients were seen at the University Hospital; 17 had pins and plaster and 13 had external fixation. Forty-six patients were seen at Kaiser Hospital; all had pins and plaster treatment. The complication rate for those with pins and plaster at the University Hospital was 53%; the complication for external fixation rate was 62%. The affiliated-hospital complication rate was 52%. All patients with ipsilateral forearm shaft and carpal fractures developed a nonunion of the carpal fracture. Few patients maintained anatomic reduction, and many had significant intra-articular malalignment. External fixation with threaded half pins did not obviate pin problems in our series. These methods may help manage severely comminuted distal radial fractures, but complications should be anticipated and alternative treatment considered, especially when ipsilateral carpal or forearm shaft fractures are present.  相似文献   
65.
Comminuted intraarticular fractures of the distal radius   总被引:1,自引:0,他引:1  
The comminuted intraarticular fracture of the distal radius requires early, accurate reduction of the articular surfaces and sustained restoration of anatomic position. The most commonly employed methods are pins and plaster, external fixation, percutaneous pinning, and open reduction and internal fixation. There are pitfalls, advantages, and disadvantages inherent in each method. Careful preoperative analysis of individual patients and fractures determines the therapeutic options.  相似文献   
66.
67.
68.
Epidemiologic and laboratory data suggest that coprodiagnostic methods may fail to detect Cryptosporidium oocysts in stool specimens of infected patients. To improve the efficacy of stool concentration procedures, we modified different steps of the Formalin-ethyl acetate (FEA) stool concentration technique and evaluated these modifications by examining stool samples seeded with known numbers of Cryptosporidium oocysts. Because these modifications failed to improve oocyst detection, we developed a new stool concentration technique that includes FEA sedimentation followed by layering and flotation over hypertonic sodium chloride solution to separate parasites from stool debris. Compared with the standard FEA procedure, this technique improved Cryptosporidium oocyst detection. The sensitivities of the two concentration techniques were similar for diarrheal (watery) stool specimens (100% of watery stool specimens seeded with 5,000 oocysts per g of stool were identified as positive by the new technique, compared with 90% of stools processed by the standard FEA technique). However, the most significant improvement in diagnosis occurred with formed stool specimens that were not fatty; 70 to 90% of formed stool specimens seeded with 5,000 oocysts were identified as positive by the new technique, compared with 0% of specimens processed by the standard FEA technique. One hundred percent of formed specimens seeded with 10,000 oocysts were correctly diagnosed by using the new technique, while 0 to 60% of specimens processed by the standard FEA technique were found positive. Similarly, only 50 to 90% of stool specimens seeded with 50,000 oocysts were identified as positive by using the standard FEA technique, compared with a 100% positive rate by the new technique. The new stool concentration procedure provides enhanced detection of Cryptosporidium oocysts in all stool samples.  相似文献   
69.
Ascites and plasma concentrations of soluble tumor necrosis factor receptors p55 and p75 were measured in a prospective study in 34 patients (35 occasions of ascites) with hepatic (5 infected and 21 uninfected) and malignancy-related (9) ascites. All patients had high concentrations of both soluble tumor necrosis factor receptors in ascites and plasma; these were about 500 times higher than the corresponding tumor necrosis factor-alpha concentrations. Ascites levels of soluble tumor necrosis factor receptors p55 and soluble tumor necrosis factor receptors p75 were significantly elevated in patients with malignancy-related (p55: 26.0 +/- 8.6 ng/ml; p75: 20.5 +/- 17.4 ng/ml; mean +/- S.D.) and infected ascites (p55: 25.1 +/- 10.9 ng/ml, p75: 22.6 +/- 11.0 ng/ml) compared with patients with uncomplicated hepatic ascites (p55: 10.1 +/- 4.4 ng/ml; p75: 6.0 +/- 2.6 ng/ml). Patients with infected or malignancy-related ascites also showed higher soluble tumor necrosis factor receptor concentrations in plasma than did patients with plain hepatic ascites. Successful antibiotic treatment of peritonitis reduced soluble tumor necrosis factor receptor p55 and p75 ascites levels in three patients from 24.2 +/- 15.2 ng/ml to 10.7 +/- 1.9 ng/ml and from 20.2 +/- 14.4 ng/ml to 7.5 +/- 1.8 ng/ml, respectively. Soluble tumor necrosis factor receptors p55 and p75 at cutoff levels of 16.5 ng/ml and 9.5 ng/ml, respectively, differentiated between infected or malignant and plain hepatic ascites with diagnostic accuracies of 94% and 89%, respectively. They did not differentiate between infected and malignant ascites. The concentrations of soluble tumor necrosis factor receptor p55 were usually higher in ascites than in plasma in all subgroups of patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
70.
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