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   859433篇
  免费   54650篇
  国内免费   1639篇
耳鼻咽喉   11254篇
儿科学   27666篇
妇产科学   21193篇
基础医学   132365篇
口腔科学   25099篇
临床医学   72561篇
内科学   168029篇
皮肤病学   20333篇
神经病学   61821篇
特种医学   29471篇
外国民族医学   77篇
外科学   122248篇
综合类   15561篇
现状与发展   2篇
一般理论   186篇
预防医学   69943篇
眼科学   20368篇
药学   65817篇
  3篇
中国医学   2955篇
肿瘤学   48770篇
  2021年   7691篇
  2019年   8047篇
  2018年   12492篇
  2017年   8986篇
  2016年   9656篇
  2015年   10724篇
  2014年   13750篇
  2013年   20758篇
  2012年   29922篇
  2011年   31459篇
  2010年   17627篇
  2009年   15469篇
  2008年   28137篇
  2007年   30290篇
  2006年   30308篇
  2005年   28492篇
  2004年   27452篇
  2003年   25953篇
  2002年   25148篇
  2001年   40733篇
  2000年   41844篇
  1999年   34140篇
  1998年   8537篇
  1997年   7058篇
  1996年   7383篇
  1995年   6990篇
  1994年   6397篇
  1992年   25029篇
  1991年   24797篇
  1990年   24158篇
  1989年   23663篇
  1988年   21545篇
  1987年   20826篇
  1986年   19916篇
  1985年   18660篇
  1984年   13673篇
  1983年   11587篇
  1982年   6371篇
  1979年   12657篇
  1978年   8885篇
  1977年   7571篇
  1976年   7294篇
  1975年   8099篇
  1974年   9584篇
  1973年   9263篇
  1972年   8727篇
  1971年   8164篇
  1970年   7851篇
  1969年   7344篇
  1968年   6849篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
1.
2.
3.
4.
5.

Aims

To examine the influence of pre-existing psychiatric disorder on the choice of treatment in patients with gynaecological cancer.

Materials and methods

The analyses were based on all patients who underwent surgical treatment for endometrial, ovarian or cervical cancer who were registered in the Danish Gynecological Cancer Database in the years 2007–2014 (3059 patients with ovarian cancer, 5100 patients with endometrial cancer and 1150 with cervical cancer). Logistic regression model and Cox regression model, adjusted for relevant confounders, were used to estimate the effect of pre-existing psychiatric disorder on the course of cancer treatment. Our outcomes were (i) presurgical oncological treatment, (ii) macroradical surgery for patients with ovarian cancer, (iii) radiation/chemotherapy within 30 days and 100 days after surgery and (iv) time from surgery to first oncological treatment.

Results

In the group of patients with ovarian cancer, more patients with a psychiatric disorder received macroradical surgery versus patients without a psychiatric disorder, corresponding to an adjusted odds ratio of 1.24 (95% confidence interval 0.62–2.41) and the chance for having oncological treatment within 100 days was odds ratio = 1.26 (95% confidence interval 0.77–2.10). As for patients with endometrial cancer, all outcome estimates were close to unity. The adjusted odds ratio for oncological treatment within 30 days after surgery in patients with cervical cancer with a history of psychiatric disorder was 0.20 (95% confidence interval 0.03–1.54).

Conclusions

We did not find any significant differences in the treatment of ovarian and endometrial cancer in patients with pre-existing psychiatric diagnoses. When it comes to oncological treatment, we suggest that increased attention should be paid to patients with cervical cancer having a pre-existing psychiatric diagnosis.  相似文献   
6.
7.
8.
Abstract

This study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos.  相似文献   
9.
10.

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   
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