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   2572篇
  免费   166篇
  国内免费   25篇
耳鼻咽喉   18篇
儿科学   169篇
妇产科学   37篇
基础医学   307篇
口腔科学   52篇
临床医学   237篇
内科学   520篇
皮肤病学   28篇
神经病学   126篇
特种医学   499篇
外科学   232篇
综合类   40篇
一般理论   1篇
预防医学   157篇
眼科学   22篇
药学   118篇
中国医学   4篇
肿瘤学   196篇
  2022年   8篇
  2021年   23篇
  2020年   19篇
  2019年   19篇
  2018年   27篇
  2017年   25篇
  2016年   32篇
  2015年   38篇
  2014年   46篇
  2013年   90篇
  2012年   80篇
  2011年   70篇
  2010年   104篇
  2009年   89篇
  2008年   81篇
  2007年   78篇
  2006年   81篇
  2005年   60篇
  2004年   55篇
  2003年   55篇
  2002年   46篇
  2001年   44篇
  2000年   57篇
  1999年   56篇
  1998年   142篇
  1997年   123篇
  1996年   132篇
  1995年   96篇
  1994年   80篇
  1993年   87篇
  1992年   48篇
  1991年   48篇
  1990年   44篇
  1989年   85篇
  1988年   64篇
  1987年   71篇
  1986年   60篇
  1985年   56篇
  1984年   35篇
  1983年   40篇
  1982年   36篇
  1981年   21篇
  1980年   38篇
  1979年   16篇
  1978年   22篇
  1977年   22篇
  1976年   30篇
  1975年   25篇
  1972年   7篇
  1965年   6篇
排序方式: 共有2763条查询结果,搜索用时 15 毫秒
1.
In 17 cases the author has removed intraglandular submandibular calculi by an oral route utilizing blunt soft tissue dissection after an incision of the mucosa only. General anesthesia is used and the patient discharged after an overnight stay. No complications were encountered. All patients were back on full diet in 48 hours.  相似文献   
2.
PURPOSE: Bevacizumab, a monoclonal antibody against vascular endothelial growth factor, increases survival when combined with irinotecan-based chemotherapy in first-line treatment of metastatic colorectal cancer (CRC). This randomized, phase II trial compared bevacizumab plus fluorouracil and leucovorin (FU/LV) versus placebo plus FU/LV as first-line therapy in patients considered nonoptimal candidates for first-line irinotecan. PATIENTS AND METHODS: Patients had metastatic CRC and one of the following characteristics: age > or = 65 years, Eastern Cooperative Oncology Group performance status 1 or 2, serum albumin < or = 3.5 g/dL, or prior abdominal/pelvic radiotherapy. Patients were randomly assigned to FU/LV/placebo (n = 105) or FU/LV/bevacizumab (n = 104). The primary end point was overall survival. Secondary end points were progression-free survival, response rate, response duration, and quality of life. Safety was also assessed. RESULTS: Median survival was 16.6 months for the FU/LV/bevacizumab group and 12.9 months for the FU/LV/placebo group (hazard ratio, 0.79; P = .16). Median progression-free survival was 9.2 months (FU/LV/bevacizumab) and 5.5 months (FU/LV/placebo); hazard ratio was 0.50; P = .0002. Response rates were 26.0% (FU/LV/bevacizumab) and 15.2% (FU/LV/placebo) (P = .055); duration of response was 9.2 months (FU/LV/bevacizumab) and 6.8 months (FU/LV/placebo); hazard ratio was 0.42; P = .088. Grade 3 hypertension was more common with bevacizumab treatment (16% v 3%) but was controlled with oral medication and did not cause study drug discontinuation. CONCLUSION: Addition of bevacizumab to FU/LV as first-line therapy in CRC patients who were not considered optimal candidates for first-line irinotecan treatment provided clinically significant patient benefit, including statistically significant improvement in progression-free survival.  相似文献   
3.
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
4.
5.
6.
7.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
8.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
  相似文献   
9.
10.
Localized 1H NMR spectra of glutamate in the human brain.   总被引:2,自引:0,他引:2  
Localized 1H NMR spectra at TE = 12 ms were obtained from cerebral cortex of human subjects using ISIS with surface suppression. The 2.29-ppm resonance was assigned to C4 glutamate with contributions from C4 glutamine and GABA using in vivo spectral editing and comparison of chemical shift with pure compounds. The measured intensity ratio between the 2.29 resonance and the creatine resonance at 3.03 ppm was in good agreement with the ratio predicted from previously reported measurements of glutamate, glutamine, and GABA concentrations in biopsied human brain tissue.  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