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   728966篇
  免费   49903篇
  国内免费   1461篇
耳鼻咽喉   9411篇
儿科学   23907篇
妇产科学   18051篇
基础医学   113144篇
口腔科学   20671篇
临床医学   65431篇
内科学   140364篇
皮肤病学   16464篇
神经病学   51544篇
特种医学   26679篇
外国民族医学   76篇
外科学   108231篇
综合类   14902篇
现状与发展   2篇
一般理论   170篇
预防医学   52555篇
眼科学   16581篇
药学   55273篇
  3篇
中国医学   2411篇
肿瘤学   44460篇
  2021年   6223篇
  2019年   6059篇
  2018年   8684篇
  2017年   6652篇
  2016年   7424篇
  2015年   8266篇
  2014年   11227篇
  2013年   16533篇
  2012年   22394篇
  2011年   23298篇
  2010年   13819篇
  2009年   12875篇
  2008年   21533篇
  2007年   23022篇
  2006年   23364篇
  2005年   21795篇
  2004年   21161篇
  2003年   20017篇
  2002年   19513篇
  2001年   36451篇
  2000年   36981篇
  1999年   30514篇
  1998年   8048篇
  1997年   6807篇
  1996年   7106篇
  1995年   6766篇
  1994年   6206篇
  1992年   23030篇
  1991年   22974篇
  1990年   22385篇
  1989年   22128篇
  1988年   20091篇
  1987年   19450篇
  1986年   18523篇
  1985年   17342篇
  1984年   12750篇
  1983年   10787篇
  1982年   5977篇
  1979年   11544篇
  1978年   8161篇
  1977年   6854篇
  1976年   6612篇
  1975年   7285篇
  1974年   8504篇
  1973年   8163篇
  1972年   7676篇
  1971年   7137篇
  1970年   6889篇
  1969年   6314篇
  1968年   5785篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
5.
6.

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   
7.
8.
9.
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   
10.

Introduction

In the United States there has been a large increase in participation in lacrosse for both males and females. The purpose of this study was to analyze the number of head injuries, injury rates (calculated using the reported number of participants) and types of head injuries that are seen in emergency departments in the United States.

Methods

We compared injuries between male and female lacrosse participants. This was a retrospective study using a publicly available database produced by the US Consumer Product Safety Commission and information about lacrosse participation from US Lacrosse.

Results

A linear regression was performed and showed a positive correlation between number of head injuries to males and time from 2002 to 2010 (R2?=?0.823; p?=?0.001). While the number of injuries to the head in female lacrosse participants was not significant. There was a negative correlation between the number of head injuries to males from 2010 to 2016 (R2?=?0.800; p?=?0.007), but again, there was no significance for female injury count (R2?=?0.417; p?=?0.117). Other significant differences between head injuries in males and females included the mechanism of injury and the type of injury recorded.

Conclusion

The most recent data from 2010 to 2016, suggest that both males and females have had a decrease in injury rate. However the total number of female head injuries is not significantly decreasing and as the sport continues to grow there will likely be more total head injuries and visits to the emergency department.  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