| 收费全文 | 511728篇 |
| 免费 | 33967篇 |
| 国内免费 | 608篇 |
| 耳鼻咽喉 | 6892篇 |
| 儿科学 | 16825篇 |
| 妇产科学 | 13521篇 |
| 基础医学 | 84806篇 |
| 口腔科学 | 14455篇 |
| 临床医学 | 44107篇 |
| 内科学 | 92986篇 |
| 皮肤病学 | 12145篇 |
| 神经病学 | 36169篇 |
| 特种医学 | 18447篇 |
| 外国民族医学 | 63篇 |
| 外科学 | 76916篇 |
| 综合类 | 8440篇 |
| 一般理论 | 118篇 |
| 预防医学 | 38831篇 |
| 眼科学 | 12101篇 |
| 药学 | 40468篇 |
| 中国医学 | 992篇 |
| 肿瘤学 | 28021篇 |
| 2018年 | 4927篇 |
| 2015年 | 4512篇 |
| 2014年 | 6062篇 |
| 2013年 | 9546篇 |
| 2012年 | 12877篇 |
| 2011年 | 14285篇 |
| 2010年 | 8305篇 |
| 2009年 | 7778篇 |
| 2008年 | 13707篇 |
| 2007年 | 14707篇 |
| 2006年 | 14944篇 |
| 2005年 | 14366篇 |
| 2004年 | 14058篇 |
| 2003年 | 13398篇 |
| 2002年 | 13277篇 |
| 2001年 | 24072篇 |
| 2000年 | 25082篇 |
| 1999年 | 20557篇 |
| 1998年 | 5426篇 |
| 1997年 | 4687篇 |
| 1996年 | 4757篇 |
| 1995年 | 4592篇 |
| 1994年 | 4306篇 |
| 1993年 | 4123篇 |
| 1992年 | 15706篇 |
| 1991年 | 16307篇 |
| 1990年 | 16418篇 |
| 1989年 | 15788篇 |
| 1988年 | 14568篇 |
| 1987年 | 14412篇 |
| 1986年 | 13587篇 |
| 1985年 | 12974篇 |
| 1984年 | 9612篇 |
| 1983年 | 8236篇 |
| 1982年 | 4543篇 |
| 1981年 | 4215篇 |
| 1979年 | 9405篇 |
| 1978年 | 6838篇 |
| 1977年 | 5754篇 |
| 1976年 | 5588篇 |
| 1975年 | 6379篇 |
| 1974年 | 7630篇 |
| 1973年 | 7124篇 |
| 1972年 | 6953篇 |
| 1971年 | 6680篇 |
| 1970年 | 6166篇 |
| 1969年 | 5886篇 |
| 1968年 | 5557篇 |
| 1967年 | 5009篇 |
| 1966年 | 4449篇 |
下载免费PDF全文 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 下载免费PDF全文 Visible light spectroscopy (VLS) represents a sensitive, non-invasive method to quantify tissue oxygen levels and detect hypoxemia. The aim of this study was to assess the microperfusion patterns of the gastric pouch during laparoscopic Roux-en-Y gastric bypass (LRYGB) using the VLS technique.
MethodsTwenty patients were enrolled. Tissue oxygenation (StO2%) measurements were performed at three different localizations of the gastric wall, prior and after the creation of the gastric pouch, and after the creation of the gastro-jejunostomy.
ResultsPrior to the creation of the gastric pouch, the lowest StO2% levels were observed at the level of the distal esophagus with a median StO2% of 43 (IQR 40.8–49.5). After the creation of the gastric pouch and after the creation of the gastro-jejunostomy, the lowest StO2% levels were recorded at the level of the His angle with median values of 29% (IQR 20–38.5) and 34.5% (IQR 19–39), respectively. The highest mean StO2 reduction was recorded at the level of the His angle after the creation of the gastric pouch, and it was 18.3% (SD ± 18.1%, p < 0.001). A reduction of StO2% was recorded at all localizations after the formation of the gastro-jejunostomy compared to the beginning of the operation, but the mean differences of the StO2% levels were statistically significant only at the resection line of the pouch and at the His angle (p = 0.044 and p < 0.001, respectively).
ConclusionGastric pouch demonstrates reduction of StO2% during LRYGB. VLS is a useful technique to assess microperfusion patterns of the stomach during LRYGB.
Graphical abstract