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   230676篇
  免费   5456篇
  国内免费   201篇
耳鼻咽喉   1682篇
儿科学   8729篇
妇产科学   4477篇
基础医学   24036篇
口腔科学   2393篇
临床医学   18685篇
内科学   40907篇
皮肤病学   1530篇
神经病学   22917篇
特种医学   10257篇
外国民族医学   1篇
外科学   34735篇
综合类   2894篇
现状与发展   1篇
一般理论   88篇
预防医学   24856篇
眼科学   4013篇
药学   13513篇
中国医学   705篇
肿瘤学   19914篇
  2024年   92篇
  2023年   698篇
  2022年   1139篇
  2021年   2278篇
  2020年   1349篇
  2019年   1982篇
  2018年   23815篇
  2017年   18695篇
  2016年   20989篇
  2015年   2712篇
  2014年   3274篇
  2013年   4038篇
  2012年   11637篇
  2011年   25476篇
  2010年   20990篇
  2009年   13468篇
  2008年   22790篇
  2007年   25144篇
  2006年   3781篇
  2005年   5278篇
  2004年   6183篇
  2003年   6782篇
  2002年   4805篇
  2001年   626篇
  2000年   706篇
  1999年   574篇
  1998年   690篇
  1997年   588篇
  1996年   400篇
  1995年   445篇
  1994年   347篇
  1993年   338篇
  1992年   250篇
  1991年   266篇
  1990年   299篇
  1989年   242篇
  1988年   188篇
  1987年   191篇
  1986年   171篇
  1985年   201篇
  1984年   185篇
  1983年   176篇
  1982年   221篇
  1981年   215篇
  1980年   229篇
  1979年   120篇
  1978年   125篇
  1977年   134篇
  1976年   115篇
  1975年   76篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Objectives: Currently in Ghana, there is an on-going task-shifting strategy in which nurses are trained in hypertension management. While this study will provide useful information on the viability of this approach, it is not clear how patients in the intervention perceive hypertension, the task-shifting strategy, and its effects on blood pressure management. The objective of this paper is to examine patients’ perceptions of hypertension and hypertension management in the context of an on-going task-shifting intervention to manage blood pressure control in Ghana.

Design: Forty-two patients participating in the Task Shifting Strategy for Hypertension program (23 males, 19 females, and mean age 61. 7 years) completed in-depth, qualitative interviews. Interviews were transcribed, and key words and phrases were extracted and coded using the PEN-3 Cultural Model as a guide through open and axial coding techniques, thus allowing rich exploration of the data.

Results: Emergent themes included patients’ perceptions of hypertension, which encompassed misperceptions of hypertension and blood pressure control. Additional themes included enablers and barriers to hypertension management, and how the intervention nurtured lifestyle change associated with blood pressure control. Primary enabling factors included the supportive nature of TASSH nurses, while notable barriers were financial constraints and difficulty accessing medication. Nurturing factors included the motivational interviewing and patient counseling which instilled confidence in the patients that they could make lasting behavior changes.

Conclusions: This study offers a unique perspective of blood pressure control by examining how patients view an on-going task-shifting initiative for hypertension management. The results of this study shed light on factors that can help and hinder individuals in low-resource settings with long-term blood pressure management.  相似文献   

5.

Background

There are well-established relationships between health and homelessness, and shelters can facilitate the transmission of diseases and contribute to their prevention. Adequate environmental health conditions and hygiene behaviors in homeless shelters are fundamental to the health of their clients, a marginalized population. We report the status of environmental health conditions and hygiene behaviors in homeless shelters and associated health outcomes; interventions to improve these conditions, behaviors, and outcomes; and obstacles to improvement.

Methods

PubMed, Web of Science, Scopus, and EBSCOhost were searched for peer-reviewed studies, and additional sources for grey literature. Studies were included if they reported primary data on one or more environmental health condition or hygiene behavior in homeless shelters.

Results

Twenty-eight studies were included in the review. Insufficient ventilation systems, unhygienic bedding, and overcrowding were the most documented environmental health and hygiene deficiencies in homeless shelters, and tuberculosis infections and skin diseases were the most documented associated health outcomes among clients. Studies frequently recommended or described implementation of behavioral and administrative controls, ventilation system improvements, and ultraviolet germicidal irradiation fixtures.

Discussion

Most studies addressed airborne transmission of tuberculosis and were conducted in high-income countries, revealing an imbalance in the literature. Insufficient resources and the transience of clients are barriers to improving hygiene behaviors and environmental conditions in homeless shelters. Further investment and research into ensuring adequate hygiene and environmental health in this setting can protect and promote the health and well-being of people experiencing homelessness.  相似文献   
6.
Magnetic field generated by neuronal activity could alter magnetic resonance imaging (MRI) signals but detection of such signal is under debate. Previous researches proposed that magnitude signal change is below current detectable level, but phase signal change (PSC) may be measurable with current MRI systems. Optimal imaging parameters like echo time, voxel size and external field direction, could increase the probability of detection of this small signal change. We simulate a voxel of cortical column to determine effect of such parameters on PSC signal. We extended a laminar network model for somatosensory cortex to find neuronal current in each segment of pyramidal neurons (PN). 60,000 PNs of simulated network were positioned randomly in a voxel. Biot–savart law applied to calculate neuronal magnetic field and additional phase. The procedure repeated for eleven neuronal arrangements in the voxel. PSC signal variation with the echo time and voxel size was assessed. The simulated results show that PSC signal increases with echo time, especially 100/80 ms after stimulus for gradient echo/spin echo sequence. It can be up to 0.1 mrad for echo time = 175 ms and voxel size = 1.48 × 1.48 × 2.18 mm3. With echo time less than 25 ms after stimulus, it was just acquired effects of physiological noise on PSC signal. The absolute value of the signal increased with decrease of voxel size, but its components had complex variation. External field orthogonal to local surface of cortex maximizes the signal. Expected PSC signal for tactile detection in the somatosensory cortex increase with echo time and have no oscillation.  相似文献   
7.
8.
9.
10.
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.  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