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   2084篇
  免费   118篇
  国内免费   24篇
耳鼻咽喉   3篇
儿科学   167篇
妇产科学   26篇
基础医学   204篇
口腔科学   47篇
临床医学   208篇
内科学   484篇
皮肤病学   25篇
神经病学   66篇
特种医学   501篇
外科学   227篇
综合类   31篇
预防医学   68篇
眼科学   22篇
药学   66篇
中国医学   3篇
肿瘤学   78篇
  2022年   9篇
  2021年   16篇
  2020年   14篇
  2019年   13篇
  2018年   24篇
  2017年   23篇
  2016年   27篇
  2015年   29篇
  2014年   34篇
  2013年   64篇
  2012年   34篇
  2011年   38篇
  2010年   83篇
  2009年   66篇
  2008年   50篇
  2007年   40篇
  2006年   45篇
  2005年   29篇
  2004年   24篇
  2003年   16篇
  2002年   28篇
  2001年   23篇
  2000年   37篇
  1999年   29篇
  1998年   136篇
  1997年   118篇
  1996年   124篇
  1995年   93篇
  1994年   74篇
  1993年   84篇
  1992年   36篇
  1991年   30篇
  1990年   27篇
  1989年   73篇
  1988年   57篇
  1987年   66篇
  1986年   58篇
  1985年   66篇
  1984年   34篇
  1983年   47篇
  1982年   39篇
  1981年   23篇
  1980年   41篇
  1979年   23篇
  1978年   22篇
  1977年   25篇
  1976年   34篇
  1975年   33篇
  1973年   7篇
  1971年   9篇
排序方式: 共有2226条查询结果,搜索用时 62 毫秒
1.
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   
2.
The renal and hemodynamic effects of dopamine were measured during the immediate postoperative period in six infants following repair of congenital cardiac defects. Dopamine was infused at rates of 5, 10, and 15 micrograms/kg/min. Cardiac index (CI) increased significantly at a dopamine infusion rate of 15 micrograms/kg/min. The glomerular filtration rate (GFR) and urine output increased at dopamine infusion rates of 5 and 10 micrograms/kg/min and returned to baseline at 15 micrograms/kg/min. No significant changes occurred in right atrial pressure (RAP), left atrial pressure (LAP), systemic artery pressure, systemic vascular resistance (SVR), or pulmonary vascular resistance (PVR). Heart rate (HR) increased slightly at a dopamine infusion rate of 15 micrograms/kg/min. Pulmonary artery pressure (PAP) increased significantly in only one patient. These data demonstrate that infants require high doses of dopamine to produce the hemodynamic effects seen in adults and that these higher doses may be used without adverse renal effects.  相似文献   
3.
4.
5.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
6.
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   
7.
8.
9.
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
10.
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