首页 | 官方网站   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   3726篇
  免费   154篇
  国内免费   65篇
医药卫生   3945篇
  2022年   13篇
  2021年   86篇
  2020年   31篇
  2019年   59篇
  2018年   83篇
  2017年   49篇
  2016年   43篇
  2015年   60篇
  2014年   98篇
  2013年   138篇
  2012年   175篇
  2011年   217篇
  2010年   123篇
  2009年   126篇
  2008年   158篇
  2007年   188篇
  2006年   195篇
  2005年   197篇
  2004年   172篇
  2003年   163篇
  2002年   161篇
  2001年   145篇
  2000年   130篇
  1999年   112篇
  1998年   54篇
  1997年   30篇
  1996年   37篇
  1995年   34篇
  1994年   22篇
  1993年   13篇
  1992年   41篇
  1991年   55篇
  1990年   63篇
  1989年   65篇
  1988年   60篇
  1987年   74篇
  1986年   49篇
  1985年   65篇
  1984年   33篇
  1983年   30篇
  1982年   21篇
  1981年   14篇
  1980年   13篇
  1979年   33篇
  1978年   13篇
  1977年   14篇
  1974年   28篇
  1973年   21篇
  1972年   22篇
  1971年   25篇
排序方式: 共有3945条查询结果,搜索用时 16 毫秒
1.
2.
3.
4.
5.
6.
In the presented paper the authors evaluate the long-term results of treatment for inflammatory and thromboembolic complications in knee joint alloplasty with cemented endoprostheses. The clinical material spanning the years 1998-2003 are 15 patients with analysed complications, it determine 9% of all operated. They have evaluated achieved results using the HSS knee rating scale in their own modification. As far as the authors are concerned, venographic examination is a prerequisite for appropriate care of the patients following knee joint alloplasty who might have deep venous thrombosis. It is necessary to provide similar treatment when developing infections are suspected in the perioperative period and in cases of late infections. Consequently, antibiotic therapy and a possible quick bacteriological checkup for healing a postoperative wound is a prerequisite for successful treatment. Achieved results induce statement, that thromboembolic and inflammatory complications caused at most operated chronic vein insufficiency, deficit of range of motion at operated joint and gait insufficiency. Thromboembolic complications was always related with inflammation of knee joint alloplasty in our own material.  相似文献   
7.
PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors.  相似文献   
8.
Each year more than 1 million people in the United States suffer from acute myocardial infarction (MI) with most of the deaths occurring within hours of symptom onset. Over the last 25 years, different prehospital systems have evolved throughout the world which allow early cardiac monitoring and treatment of acute MI patients. Thrombolytic therapy in acute MI has been shown to decrease mortality and preserve left ventricular function when administered early after onset of symptoms. The potential role of Emergency Medical Services or Mobile Coronary Care Units in achieving early thrombolysis is under investigation. Several studies of prehospital interventions to achieve early thrombolysis are reviewed. The use of thrombolytics by prehospital personnel has been found to be feasible, safe, and effective in reducing time delays. However, whether this translates into clinical benefit remains to be seen.  相似文献   
9.
Existing guidelines advise adolescents with asthma and allergies against high-risk occupations. The aim of the current authors' analyses was to investigate the resulting self-selection in a prospective cohort study. The participants of Phase II of the International Study of Asthma and Allergies in Childhood in Germany (aged 9-11 yrs at baseline) were re-contacted after 7 yrs (response rate was 77%) and were asked to complete a questionnaire, which included items on atopic diseases. The subjects were also asked about the type of job they would like to have in the future (preferred job choice). Exposure to agents with potential asthma risk was evaluated using a job exposure matrix. The analyses were restricted to those in school-based vocational training programmes without occupational exposures. A total of 33% of subjects chose jobs with high asthma risk, 23% selected low asthma risk jobs and the remaining adolescents indicated jobs without known asthma risk (reference category). There were no statistically significant associations between asthma, allergic rhinitis or atopic dermatitis and selecting jobs with asthma risk. Participants with allergic rhinitis tended to select high risk jobs less frequently. In conclusion, self-selection into low risk jobs seems to play a minor role in teenagers with asthma or allergies.  相似文献   
10.
The purpose of the present paper was to demonstrate the antitumor activity of lymphocytes and antibodies in the antibody-dependent cell-mediated cytotoxicity test (ADCC) in relation to the tumor growth in adult and aging rats bearing a methylcholanthrene-induced sarcoma (MC-Sa). In the syngeneic system using the ADCC test effector spleen lymphocytes, 51Cr labeled MC-Sa target cells and anti-MC-Sa serum were derived from inbred male Wistar rats. It was found that adult and aging tumor-bearing rats possessed lymphocytes (LSa) and antibodies (Ab) which were active in ADCC. In comparative studies between the groups of adult and aging rats a reverse relationship between tumor growth and activity of LSa and Ab in the ADCC test has been found. Thus, the larger weight of tumors in the group of adult rats was followed by lower LSa and Ab activities in the ADCC test. On the other hand, the smaller tumor growth in the group of aging rats was followed by higher activities of LSa and Ab in this test. We suggest that the ADCC phenomenon could be one of the antitumor mechanisms especially effective in aging rats.  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-23

京公网安备 11010802026262号