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   72657篇
  免费   4700篇
  国内免费   521篇
耳鼻咽喉   821篇
儿科学   2299篇
妇产科学   1663篇
基础医学   10358篇
口腔科学   1513篇
临床医学   6775篇
内科学   15329篇
皮肤病学   1544篇
神经病学   6222篇
特种医学   2563篇
外国民族医学   17篇
外科学   9408篇
综合类   1489篇
现状与发展   2篇
一般理论   16篇
预防医学   5849篇
眼科学   1364篇
药学   5259篇
  6篇
中国医学   739篇
肿瘤学   4642篇
  2023年   575篇
  2022年   1040篇
  2021年   2025篇
  2020年   1219篇
  2019年   1640篇
  2018年   2193篇
  2017年   1629篇
  2016年   1675篇
  2015年   1854篇
  2014年   2361篇
  2013年   3259篇
  2012年   4826篇
  2011年   4921篇
  2010年   2756篇
  2009年   2318篇
  2008年   3815篇
  2007年   3966篇
  2006年   3814篇
  2005年   3718篇
  2004年   3385篇
  2003年   3243篇
  2002年   3071篇
  2001年   1934篇
  2000年   1959篇
  1999年   1656篇
  1998年   589篇
  1997年   491篇
  1996年   443篇
  1995年   394篇
  1994年   371篇
  1993年   302篇
  1992年   871篇
  1991年   845篇
  1990年   768篇
  1989年   746篇
  1988年   688篇
  1987年   643篇
  1986年   607篇
  1985年   608篇
  1984年   416篇
  1983年   322篇
  1982年   223篇
  1981年   197篇
  1979年   360篇
  1978年   212篇
  1977年   235篇
  1975年   199篇
  1974年   249篇
  1973年   190篇
  1972年   215篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
European Radiology - The strongest adverse prognostic factor in myxoid/round cell liposarcomas (MRC-LPS) is the presence of a round cell component above 5% within the tumor bulk. Its identification...  相似文献   
3.
4.
5.
6.

Objective

To systematically review literature on uptake and timeliness of diphtheria-tetanus-pertussis, measles-mumps-rubella, and/or polio-containing vaccines in infants who were born preterm, with a low birth weight, and/or with chronic health conditions that were diagnosed within the first 6?months of life.

Methods

Using a standardized search strategy developed by a medical librarian, records were extracted from MEDLINE, Embase, Database of Abstracts of Reviews of Effects, and CINAHL up to May 8, 2018.

Results

Out of the 1997 records that were screened, we identified 21 studies that met inclusion criteria. Eleven studies assessed vaccine coverage and/or timeliness in preterm infants, 6 in low birth weight infants, and 7 in children with chronic health conditions. Estimates of coverage in these populations were highly variable, ranging from 40% to 100% across the vaccines and population groups.

Conclusions

There is a lack of studies reporting coverage and timeliness of routine immunizations in special populations of children.

Policy implications

Our review suggests a need for improved surveillance of immunization status in special populations of infants, as well as a need for standardization of reporting practices.  相似文献   
7.
8.
9.
It is hypothesized that persons who use drugs (PWUD) in Vietnam who are also HIV-positive may face additional challenges in psychosocial outcomes, and these challenges may extend to their family members. In this study, we examined depressive symptoms, stigma, social support, and caregiver burden of HIV-positive PWUD and their family members, compared to the outcomes of HIV-negative PWUD and their family members. Baseline, 3-month, and 6-month assessment data were gathered from 83 PWUD and 83 family members recruited from four communes in Phú Th? Province, Vietnam. For PWUD, although we observed a general decline in overall stigma over time for both groups, HIV-positive PWUD consistently reported significantly higher overall stigma for all three periods. Depressive symptoms among family members in both groups declined over time; however, family members of HIV-positive PWUD reported higher depressive symptoms across all three periods. In addition, family members of HIV-positive PWUD reported lower levels of tangible support across all three periods. Caregiver burden among family members of HIV-positive PWUD increased significantly over time, whereas the reported burden among family members of HIV-negative PWUD remained relatively unchanged. The findings highlight the need for future interventions for PWUD and family members, with targeted and culturally specific strategies to focus on the importance of addressing additional stigma experienced by PWUD who are HIV-positive. Such challenges may have direct negative impact on their family members' depressive symptoms, tangible support, and caregiver burden.  相似文献   
10.
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