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   9367篇
  免费   1479篇
  国内免费   191篇
耳鼻咽喉   55篇
儿科学   241篇
妇产科学   116篇
基础医学   544篇
口腔科学   155篇
临床医学   1664篇
内科学   1597篇
皮肤病学   70篇
神经病学   1008篇
特种医学   80篇
外科学   446篇
综合类   857篇
预防医学   846篇
眼科学   147篇
药学   2219篇
  19篇
中国医学   802篇
肿瘤学   171篇
  2024年   69篇
  2023年   350篇
  2022年   458篇
  2021年   698篇
  2020年   721篇
  2019年   576篇
  2018年   548篇
  2017年   519篇
  2016年   482篇
  2015年   440篇
  2014年   783篇
  2013年   812篇
  2012年   538篇
  2011年   540篇
  2010年   446篇
  2009年   411篇
  2008年   359篇
  2007年   312篇
  2006年   314篇
  2005年   245篇
  2004年   172篇
  2003年   154篇
  2002年   166篇
  2001年   130篇
  2000年   103篇
  1999年   72篇
  1998年   65篇
  1997年   54篇
  1996年   53篇
  1995年   37篇
  1994年   39篇
  1993年   30篇
  1992年   45篇
  1991年   27篇
  1990年   23篇
  1989年   24篇
  1988年   19篇
  1987年   20篇
  1986年   18篇
  1985年   34篇
  1984年   30篇
  1983年   13篇
  1982年   16篇
  1981年   16篇
  1980年   14篇
  1979年   7篇
  1978年   5篇
  1977年   6篇
  1975年   6篇
  1974年   6篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
1.
2.
ObjectivesPrior evidence suggests that sleep duration and sleep difficulties may be associated with cognitive function in old age, but little is known about the sleep–cognition association in late mid-life. Our aim was to examine the associations of accelerometer-based sleep duration as well as subjective sleep difficulties with different domains of cognitive function among aging workers.MethodsThe study population consisted of 289 participants (mean age 62.4 years, SD 1.02; 83% women) from the Finnish Retirement and Aging Study (FIREA). Sleep difficulties were measured using Jenkins Sleep Problem Scale (difficulties falling asleep, difficulties maintaining sleep, waking up too early in the morning, and nonrestorative sleep). Sleep duration was measured with wrist-worn accelerometer and self-report, and participants were divided into short (<7 h/night), mid-range (7–9 h/night) and long (≥9 h/night) sleepers. Participants underwent extensive cognitive testing covering three domains: (1) memory, (2) executive function, and (3) attention and information processing.ResultsGreater difficulties in waking up too early in the morning were associated with poorer executive function measured with Spatial Working Memory (SWM) test (p = 0.005). Additionally, nonrestorative sleep was associated with poorer executive function measured with Trail Making Test, B–A, (p = 0.036) and borderline significantly with lower SWM (p = 0.056). Compared to mid-range sleepers, long sleepers tended to have poorer cognitive function (all memory function tests and SWM), but the associations were not statistically significant due to small number of long sleepers.ConclusionsSubjective sleep difficulties may be linked to poorer executive function in a relatively healthy population of older workers in their 60 s. Thus, promoting good sleep quality may translate into better cognitive health in late mid-life.  相似文献   
3.
通过对中医古籍中有关升降散论述的文献梳理,全面探讨其内涵。本方是在大黄、僵蚕为雏形的基础上增加蝉蜕、姜黄而成方,几经易名,终在杨璿《伤寒瘟疫条辨》中为后人所熟知。本方广泛用于治疗瘟疫,以丸剂、散剂为主,方便携带,便于服用;重用大黄旨在祛邪、逐秽;应用时视人之体质强弱和量其毒之轻重而判断用药多寡,并辅以米酒、生蜜等以顾护正气。杨璿将其由治疗“热疫”的专方扩展为治疗“表里三焦大热”的通用方剂,扩大了本方治疗疾病范围。  相似文献   
4.
5.
ObjectivesTo explore the relationships among potentially modifiable factors related to childbirth and effective breastfeeding initiation at approximately 36 hours after birth and duration and exclusivity at hospital discharge, 2 weeks, 2 months, and 6 months after birth in primiparous women and to explore whether modifiable and nonmodifiable secondary factors and covariates influenced the relationships among factors related to childbirth and these breastfeeding outcomes.DesignA prospective, longitudinal, cohort study.SettingThe postpartum units of two general hospitals in eastern Canada.ParticipantsNinety-seven mother–infant dyads.MethodsWe recorded demographic, childbirth, obstetric history, and breastfeeding data through chart review. A breastfeeding observation was completed at approximately 36 hours after birth by unit nurses. Participants maintained breastfeeding logs in hospital and for 6 months after birth and completed three self-report questionnaires before discharge. We analyzed outcomes using backward stepwise linear and logistic regression.ResultsOne childbirth factor, labor induced with oxytocin, was negatively associated with effective initiation of breastfeeding, and none was related to breastfeeding duration and exclusivity at any time point. Maternal weight; professional support; and newborn’s gestational age at birth, 5-minute Apgar score, weight loss, LATCH score, and active feeds (newborn actively suckled at the breast) were significantly associated with breastfeeding outcomes.ConclusionInduction of labor with oxytocin should be used judiciously; when used, nurses must be hypervigilant to assess the mother–infant dyad for breastfeeding issues and to intervene to prevent or remediate them.  相似文献   
6.
7.
青光眼是致盲的主要原因之一,构成视神经的神经节细胞轴突受到多种因素的损伤,其机制尚未完全明了。青光眼最重要的危险因素是眼压升高。由于青光眼的视神经损伤尚不能直接治疗,根据目前提供的唯一已知可治疗的危险因素,可以降低升高的眼压,而眼压与房水流出通道的功能息息相关。这些方面的药物均可以影响青光眼的进展。随着医疗技术的发展以及对青光眼发病机制认识的加深,新型抗青光眼药物也应运而生,为眼科医师提供新的选择。本文将对国内外新型抗青光眼药物从机制、药理特点及临床疗效等方面进行综述。  相似文献   
8.
9.
Low-income food pantry clients are unable to adhere to the diet and physical activity recommendations of the American Diabetes Association. The aim of the study is to test the feasibility of using a mobile phone app to improve diabetes medication adherence. Clients with uncontrolled type 2 diabetes were enrolled in a mobile phone app featuring 70 days of text message reminders and incentives. The app and the 4-item Morisky Medication Adherence Scale evaluated medication adherence. Clinically significant medication adherence of 93% was achieved with use of the app. Phone app use is feasible among urban low-income clients to improve medication adherence.  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