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   20244篇
  免费   1276篇
  国内免费   138篇
耳鼻咽喉   162篇
儿科学   500篇
妇产科学   413篇
基础医学   2300篇
口腔科学   779篇
临床医学   1918篇
内科学   4531篇
皮肤病学   410篇
神经病学   1198篇
特种医学   466篇
外国民族医学   5篇
外科学   2757篇
综合类   527篇
一般理论   15篇
预防医学   1637篇
眼科学   755篇
药学   1884篇
中国医学   218篇
肿瘤学   1183篇
  2024年   30篇
  2023年   262篇
  2022年   726篇
  2021年   1123篇
  2020年   742篇
  2019年   902篇
  2018年   1067篇
  2017年   746篇
  2016年   805篇
  2015年   825篇
  2014年   1098篇
  2013年   1274篇
  2012年   1729篇
  2011年   1782篇
  2010年   1064篇
  2009年   814篇
  2008年   1191篇
  2007年   1068篇
  2006年   922篇
  2005年   784篇
  2004年   627篇
  2003年   515篇
  2002年   462篇
  2001年   87篇
  2000年   105篇
  1999年   92篇
  1998年   79篇
  1997年   60篇
  1996年   58篇
  1995年   52篇
  1994年   34篇
  1993年   42篇
  1992年   47篇
  1991年   31篇
  1990年   40篇
  1989年   45篇
  1988年   39篇
  1987年   21篇
  1986年   22篇
  1985年   22篇
  1984年   25篇
  1983年   27篇
  1982年   22篇
  1981年   15篇
  1980年   17篇
  1979年   16篇
  1978年   12篇
  1976年   13篇
  1974年   14篇
  1973年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Lasers in Medical Science - Melasma is a chronic, dark brown–pigmented patches and macules commonly on the face. Many treatment modalities for melasma have been used as hydroquinone, laser...  相似文献   
2.
3.
4.
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.

Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.

Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.

Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion.  相似文献   
5.
ABSTRACT

Purpose

To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR).  相似文献   
6.
7.
8.
9.
10.
Purpose: Traffic accidents are one of the major health problems in the world, being the first cause of burden of illness and the second leading cause of death in Iran. The Sistan-Baluchestan province is one of the most accidental provinces of Iran with the highest rate of accidents-caused deaths. This study was conducted to determine the risk factors associated with traffic accidents in Zahedan through 2013 to 2016. Methods: This analytical cross-sectional study was carried out on 223 drivers from Zahedan who were traumatized by traffic accident and sent to Zahedan hospitals. The data were obtained through interviews taken by the trained interviewers via refereeing to the medical records and collected in the researcher-made checklist. Census was obtained from the study subjects. For data analysis, independent t-test, one-way ANOVA, Chi-square and logistic regression were used with the Stata software version 11.0. Results: In this study, 223 male subjects with the mean age of (32.54 ± 12.95) years, 39.8% single and 60.2% married, entered for investigation. Most accidents (38.8%) occurred between 12:00 to 17:59. While driving, 47.1% of the study subjects were using cell phones, 89.1% had manual use of mobile phones, 21.9% had a habit of sending short message service (SMS) and 23.4% had sent SMS within 10 min before the accident. The one way analysis of variance showed that the mean age of individuals with marital status, driving experience, education and accident with motorcycle were significantly different (p < 0.05). Also, the multivariate logistic regression test indicated a significant relationship of smoking, ethnicity, insurance and SMS typing while driving with motorcycle accident (p < 0.05). Conclusion: In this study, SMS and smoking while driving had the highest risk among the variables studied in the motorcycle accidents. Therefore, effective education attempting to enhance people''s awareness about the consequences of using cell phone and smoking during driving to reduce traffic accidents seems necessary.  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