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   517283篇
  免费   34303篇
  国内免费   619篇
耳鼻咽喉   6937篇
儿科学   16982篇
妇产科学   13618篇
基础医学   85736篇
口腔科学   14520篇
临床医学   45072篇
内科学   94133篇
皮肤病学   12204篇
神经病学   36498篇
特种医学   18570篇
外国民族医学   63篇
外科学   77345篇
综合类   8496篇
一般理论   126篇
预防医学   39472篇
眼科学   12197篇
药学   40791篇
中国医学   1015篇
肿瘤学   28430篇
  2018年   5056篇
  2016年   4171篇
  2015年   4623篇
  2014年   6230篇
  2013年   9794篇
  2012年   13226篇
  2011年   14665篇
  2010年   8498篇
  2009年   7945篇
  2008年   14039篇
  2007年   15018篇
  2006年   15267篇
  2005年   14683篇
  2004年   14340篇
  2003年   13666篇
  2002年   13554篇
  2001年   24114篇
  2000年   25105篇
  1999年   20600篇
  1998年   5477篇
  1997年   4750篇
  1996年   5086篇
  1995年   4651篇
  1994年   4344篇
  1992年   15746篇
  1991年   16328篇
  1990年   16442篇
  1989年   15813篇
  1988年   14585篇
  1987年   14442篇
  1986年   13607篇
  1985年   12991篇
  1984年   9649篇
  1983年   8265篇
  1982年   4575篇
  1981年   4222篇
  1979年   9414篇
  1978年   6847篇
  1977年   5763篇
  1976年   5593篇
  1975年   6382篇
  1974年   7642篇
  1973年   7128篇
  1972年   6955篇
  1971年   6683篇
  1970年   6167篇
  1969年   5886篇
  1968年   5559篇
  1967年   5009篇
  1966年   4449篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.

Background and aims

Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.

Methods and results

In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.

Conclusion

SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE.  相似文献   
95.
The Latin American population has a double way of immigration, one toward the United States by proximity and another toward Spain by sociocultural affinity. This population increase is affecting organ donation and transplantation in receiving countries.

Objective

To analyze the brain death (BD) concept knowledge in the Dominican Republic immigrant population in Florida (United States) and Spain.

Method

Population under study: Population born in the Dominican Republic, resident in Florida (United States) and in Spain. Inclusion criteria: Population older than 15 years stratified by age and sex. Assessment instrument: Donation attitude questionnaire PCID-DTO-Ríos. Fieldwork: Random selection based on stratification. Immigration support association collaboration in Florida and Spain was needed to locate potential respondents. Completion was anonymous and self-administered, with verbal consent.

Results

A total of 123 respondents, 57 residents in Spain and 66 in Florida, have been included in the study. The 27% (n = 33) of the respondents knowledgeable of the BD concept consider it the death of an individual. Of the remainder, 52% (n = 64) do not know about it, and the remaining 21% (n = 26) believe it does not mean the death of a patient. No differences were observed regarding migration countries (P > .05). There was no association of the BD concept with other psychosocial factors analyzed or with the attitude toward organ donation.

Conclusions

Knowledge of the BD concept among the Dominican immigrant population is similar in Spain and Florida, and, unlike most studies, there is no objective association with the attitude toward organ donation.  相似文献   
96.
97.
98.
99.
100.
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