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   911篇
  免费   47篇
  国内免费   5篇
耳鼻咽喉   6篇
儿科学   27篇
妇产科学   14篇
基础医学   124篇
口腔科学   7篇
临床医学   69篇
内科学   137篇
皮肤病学   51篇
神经病学   186篇
特种医学   18篇
外科学   150篇
综合类   7篇
预防医学   85篇
眼科学   2篇
药学   50篇
中国医学   1篇
肿瘤学   29篇
  2022年   8篇
  2021年   12篇
  2020年   10篇
  2019年   12篇
  2018年   19篇
  2017年   16篇
  2016年   11篇
  2015年   21篇
  2014年   23篇
  2013年   27篇
  2012年   65篇
  2011年   47篇
  2010年   30篇
  2009年   37篇
  2008年   33篇
  2007年   48篇
  2006年   56篇
  2005年   40篇
  2004年   38篇
  2003年   34篇
  2002年   28篇
  2001年   30篇
  2000年   22篇
  1999年   12篇
  1998年   6篇
  1997年   7篇
  1995年   8篇
  1994年   7篇
  1993年   7篇
  1992年   26篇
  1991年   20篇
  1990年   17篇
  1989年   15篇
  1988年   11篇
  1987年   15篇
  1986年   9篇
  1985年   10篇
  1984年   7篇
  1982年   4篇
  1981年   8篇
  1979年   10篇
  1978年   8篇
  1977年   5篇
  1976年   4篇
  1975年   4篇
  1974年   5篇
  1905年   4篇
  1904年   5篇
  1903年   8篇
  1902年   5篇
排序方式: 共有963条查询结果,搜索用时 15 毫秒
1.
This third part of this series of articles on laboratory diagnostics of rheumatic diseases considers the rheumatic diseases caused by infection by microorganisms, or reactive arthritides. The basis for laboratory diagnostics of infection-reactive arthritides is the investigation of anti-infection antibodies. In some situations, DNA amplification methods may be helpful. Bacterially infected joints should be immediately examined by arthrocentesis and microscopic examination and laboratory culture of the synovial fluid.  相似文献   
2.
3.
Heterotopes Pankreasgewebe der Magenwand   总被引:2,自引:0,他引:2  
Heterotopic pancreas is an uncommon cause of gastrointestinal complaints such as epigastric pain, nausea, vomiting, and upper gastrointestinal bleeding. Despite the development of modern diagnostic procedures, it is still difficult to differentiate heterotopic pancreatic tissue from other benign or malignant gastric tumors. Local excision of the gastric wall is regarded as the diagnostic and therapeutic procedure of choice. We present two cases and an overview of the literature.  相似文献   
4.
In a multicenter study we selected 84 patients with fluctuating Parkinson's disease in order to evaluate the effects of controlled-release Sinemet 50/200 (=CR) versus standard Sinemet 25/100 (=STD) in an open-label 8-week titration period, followed by a double-blind, double-dummy 24-week treatment period. In contrast with previous double-blind studies, the efficacy of Sinemet CR proved to be significantly superior to that of Sinemet-STD according to NYUPDS and NUDS rating scales. This higher efficacy of Sinemet CR was not achieved at the expense of safety and/or tolerability. Actual total daily levodopa dosage in patients treated with Sinemet CR was increased by 33%; however, the plasma level of this dosage is calculated to be similar to that of the previous dosage of Sinemet-STD (bio-availability of Sinemet CR is 71%). Mean numbers of daily doses, off-hours, and off-periods were decreased significantly during Sinemet CR treatment. Although all other variables suggest that the number of on-hours had to be increased, statistical significance could not be reached in this respect.  相似文献   
5.
6.
We report a case of paraballism in a young female, which became apparent 4 months after initiating oral contraception. When the oral contraceptive was discontinued, the paraballism decreased and was replaced by choreic movements for a period of approximately 2 weeks. The abnormal movements disappeared gradually. Only 13 cases of paraballism have been reported in medical literature, and none has been attributed to the use of oral contraceptives.  相似文献   
7.
8.
Several procedures have been described for the culture of Clostridium difficile from stool specimens. The goal of this study was to determine the effectiveness of five of these methods for the isolation of C. difficile from feces of patients suspected of having C. difficile-associated illness. A total of 564 stool specimens were cultured by using heat shock, ethanol treatment (ET), and direct plating on Carr-Scarborough cycloserine-cefoxitin-fructose agar (CCFA) with horse blood (C/S medium), BBL CCFA medium, and Remel C. difficile agar. Cytotoxin assays were performed on all specimens. A total of 113 specimens (20%) were positive for C. difficile by one or more methods. The numbers of positive cultures by using heat shock, ET, and direct plating on C/S medium, BBL CCFA medium, and Remel C. difficile agar were 79 (70%), 89 (79%), 91 (81%), 79 (70%), and 52 (46%), respectively. We concluded that ET and direct plating on C/S medium were the most effective procedures for isolating C. difficile from stool specimens and found significant variation in the performance of modified CCFA from different manufacturers.  相似文献   
9.
Urinary dysfunction is very common in idiopathic Parkinson's disease (PD) and manifests primarily with symptoms of overactive bladder (OAB). Affection of central serotonergic systems has been suggested to play a role in OAB. The objective of this study was to evaluate whether in PD patients with OAB symptoms a specific alteration of the brainstem raphe (BR), which contains serotonergic neurons, can be detected with transcranial sonography (TCS). Of 116 PD patients enrolled, 19 had PD-related OAB symptoms (OAB+) unlike remaining 97 patients (OAB−). Patients were examined by a sonographer blinded to the clinical data. Reduced echogenicity of BR was found in 12 (63%) OAB+ patients but only in 18 (19%) of 93 assessable OAB− patients (Mann–Whitney U -test, P  < 0.001). In OAB+ patients, lower raphe echogenicity score was associated with longer duration of OAB symptoms ( anova , P  = 0.033). Other TCS findings such as echogenicity of substantia nigra, thalami, lenticular and caudate nuclei, and widths of third and lateral ventricles did not differ between OAB+ and OAB− patients. TCS findings suggest a pathogenetic role of BR in OAB related to PD. Alterations may reflect disturbance of its central serotonergic system.  相似文献   
10.
Seven different density gradient-forming materials were compared as to their efficacy for rat islet purification. Continuous density gradients were used in order to determine the bouant densities of the different pancreatic tissue components. Hand-picked islets served as a control. A significant separation of large numbers of slets from the exocrine tissue band was only seen in the albumin, dextran-40, and metrizamide gradients. Pure islet preparations could not be obtained with any of the gradients studied as none of the gradients completely separated lymph nodes, vessels, and ducts from the islets. Gradients containing sucrose resulted in low islet yields. The islet yields obtained with the other gradients were in the same range as those obtained by hand-picking. Metrizamide gave significantly higher yields than the widely used Ficoll. Judged both in terms of numbers of islets and their in vitro function, the best results were obtained with metrizamide and dextran-40.  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