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   600篇
  免费   50篇
耳鼻咽喉   2篇
儿科学   43篇
妇产科学   14篇
基础医学   67篇
口腔科学   11篇
临床医学   52篇
内科学   135篇
皮肤病学   29篇
神经病学   17篇
特种医学   83篇
外科学   43篇
综合类   28篇
预防医学   33篇
眼科学   7篇
药学   69篇
中国医学   1篇
肿瘤学   16篇
  2023年   2篇
  2021年   5篇
  2020年   5篇
  2019年   3篇
  2017年   7篇
  2016年   8篇
  2015年   10篇
  2014年   19篇
  2013年   37篇
  2012年   16篇
  2011年   11篇
  2010年   30篇
  2009年   27篇
  2008年   30篇
  2007年   20篇
  2006年   19篇
  2005年   16篇
  2004年   10篇
  2003年   21篇
  2002年   18篇
  2001年   11篇
  2000年   7篇
  1999年   9篇
  1998年   21篇
  1997年   43篇
  1996年   31篇
  1995年   20篇
  1994年   25篇
  1993年   21篇
  1992年   9篇
  1991年   5篇
  1990年   10篇
  1989年   26篇
  1988年   13篇
  1987年   11篇
  1986年   13篇
  1985年   14篇
  1984年   6篇
  1982年   2篇
  1981年   4篇
  1980年   6篇
  1979年   2篇
  1978年   4篇
  1977年   9篇
  1976年   4篇
  1975年   4篇
  1963年   1篇
  1956年   1篇
  1955年   1篇
  1932年   1篇
排序方式: 共有650条查询结果,搜索用时 750 毫秒
31.
We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs.  相似文献   
32.
Elevated circulating cholesterol can have profound effects on the health of an individual. Such excess cholesterol can promote coronary artery disease, production and accumulation of β-amyloid in the brain, and possibly Alzheimer’s disease (AD). In a clinical trial evaluating the benefit of a cholesterol-lowering drug in the treatment of AD, mean cholesterol levels at baseline among individuals participating in the trial were found to be relatively high. Based on this observation we suggest that cholesterol levels should be actively monitored in the elderly, as many individuals with AD are over 65 years of age and therefore excluded by currently accepted guidelines.  相似文献   
33.
Buddhism, the Thai state religion, teaches that use of intoxicants should be avoided. Nonetheless, many Thai people drink alcohol, and a proportion are alcohol-dependent or hazardous or harmful drinkers. This study examines the relationship between Buddhist upbringing and beliefs and alcohol use disorders in Thai men. Three groups, comprising 144 non/infrequent/light drinkers, 77 hazardous/ harmful drinkers and 91 alcohol dependents were interviewed regarding their early religious life and current religious practices and beliefs. No protective association was shown between early religious life and later alcohol use disorders; indeed, having lived as a boy in a temple for a period was commoner in those with adult alcohol problems. Few subjects reported frequent involvement in current religious activities (9, 8 and 6% in the non/infrequent/light drinkers, hazardous/harmful drinkers, and alcohol dependents respectively). Hazardous/harmful drinkers [odds ratio (OR) = 0.4, 95% confidence interval (CI) = 0.2-0.9] and alcohol dependents (OR = 0.5, 95% CI = 0.2-0.9) were less likely to report being moderately to strongly religious, than were non/infrequent/light drinkers. Understanding the association between religious beliefs and drinking behaviour can potentially assist in the development of prevention and treatment programmes.  相似文献   
34.
Using data from a 12-year prospective study, we determined the importance of the pattern of alcohol consumption as a risk factor for type 2 diabetes in a cohort of 46,892 U.S. male health professionals who completed biennial postal questionnaires. Overall, 1,571 new cases of type 2 diabetes were documented. Compared with zero alcohol consumption, consumption of 15-29 g/day of alcohol was associated with a 36% lower risk of diabetes (RR = 0.64; 95% CI 0.53-0.77). This inverse association between moderate consumption and diabetes remained if light drinkers rather than abstainers were used as the reference group (RR = 0.60, CI 0.50-0.73). There were few heavy drinkers, but the inverse association persisted to those drinking >/=50 g/day of alcohol (RR = 0.60, CI 0.43-0.84). Frequency of consumption was inversely associated with diabetes. Consumption of alcohol on at least 5 days/week provided the greatest protection, even when less than one drink per drinking day was consumed (RR = 0.48, CI 0.27-0.86). Compared with infrequent drinkers, for each additional day per week that alcohol was consumed, risk was reduced by 7% (95% CI 3-10%) after controlling for average daily consumption. There were similar and independent inverse associations for beer, liquor, and white wine. Our findings suggested that frequent alcohol consumption conveys the greatest protection against type 2 diabetes, even if the level of consumption per drinking day is low. Beverage choice did not alter risk.  相似文献   
35.
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover.  相似文献   
36.
37.
38.
Rotator cuff tear: clinical experience with sonographic detection   总被引:5,自引:0,他引:5  
Soble  MG; Kaye  AD; Guay  RC 《Radiology》1989,173(2):319-321
Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury.  相似文献   
39.
40.
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