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   2328765篇
  免费   172312篇
  国内免费   5623篇
耳鼻咽喉   30422篇
儿科学   75804篇
妇产科学   64674篇
基础医学   344348篇
口腔科学   64939篇
临床医学   223244篇
内科学   448163篇
皮肤病学   48352篇
神经病学   191424篇
特种医学   84923篇
外国民族医学   603篇
外科学   325379篇
综合类   50441篇
现状与发展   4篇
一般理论   978篇
预防医学   197980篇
眼科学   52111篇
药学   171480篇
  13篇
中国医学   4784篇
肿瘤学   126634篇
  2019年   19163篇
  2018年   26287篇
  2017年   20030篇
  2016年   21752篇
  2015年   24953篇
  2014年   34637篇
  2013年   53510篇
  2012年   73081篇
  2011年   77796篇
  2010年   45205篇
  2009年   42512篇
  2008年   72053篇
  2007年   76733篇
  2006年   76462篇
  2005年   74364篇
  2004年   71204篇
  2003年   67964篇
  2002年   65780篇
  2001年   101829篇
  2000年   104434篇
  1999年   87989篇
  1998年   25225篇
  1997年   22934篇
  1996年   22983篇
  1995年   21809篇
  1994年   20367篇
  1993年   19088篇
  1992年   70288篇
  1991年   69220篇
  1990年   67134篇
  1989年   64245篇
  1988年   59549篇
  1987年   58395篇
  1986年   55699篇
  1985年   53107篇
  1984年   40135篇
  1983年   34783篇
  1982年   20863篇
  1979年   37553篇
  1978年   27224篇
  1977年   22465篇
  1976年   21546篇
  1975年   22591篇
  1974年   27611篇
  1973年   27200篇
  1972年   25370篇
  1971年   23729篇
  1970年   22208篇
  1969年   20614篇
  1968年   19441篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
9.
Objectives: The steeling effect suggests that early-life adversity can have a beneficial impact later in life. However, little is known about its underlying mechanisms and long-term outcomes . The study aimed to examine the role of early-life adversity (ELA) on successful aging, and whether this relationship can be explained by mental and physical health.

Method: Socio-demographics, early-life adversity (ELA), individual quality of life (iQoL), and mental and physical health of 270 individuals (Mage = 66.82 years, 71.5% female) were assessed. Polynomial regressions and mediation analyses were conducted.

Results: Significant inverse U-shaped associations were found between ELA and iQoL (β = ?.59, p = .005) and between ELA and mental health (β = ?.64, p = .002), but not between ELA and physical health. Furthermore, mental health significantly mediated the relationship between ELA and iQoL (b = ?.84, BCa CI [?1.66, ?.27]).

Conclusion: Highest level of individual quality of life (i.e. successful aging) was related to a moderate amount of ELA. Additionally, mental health significantly mediated this relationship. These findings suggest that some amount of ELA could be beneficial for successful aging. Resource-focused interventions are needed to improve health and promote successful aging for an underdetected, at-risk subgroup with low early-life adversity.  相似文献   

10.

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   
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