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   4798篇
  免费   334篇
  国内免费   24篇
耳鼻咽喉   10篇
儿科学   24篇
妇产科学   38篇
基础医学   244篇
口腔科学   19篇
临床医学   365篇
内科学   493篇
皮肤病学   230篇
神经病学   103篇
特种医学   60篇
外科学   105篇
综合类   421篇
一般理论   5篇
预防医学   2806篇
眼科学   16篇
药学   140篇
  1篇
中国医学   9篇
肿瘤学   67篇
  2024年   39篇
  2023年   82篇
  2022年   205篇
  2021年   216篇
  2020年   198篇
  2019年   145篇
  2018年   137篇
  2017年   159篇
  2016年   171篇
  2015年   158篇
  2014年   286篇
  2013年   448篇
  2012年   317篇
  2011年   314篇
  2010年   226篇
  2009年   230篇
  2008年   191篇
  2007年   216篇
  2006年   151篇
  2005年   129篇
  2004年   135篇
  2003年   93篇
  2002年   77篇
  2001年   91篇
  2000年   59篇
  1999年   59篇
  1998年   63篇
  1997年   78篇
  1996年   75篇
  1995年   41篇
  1994年   63篇
  1993年   50篇
  1992年   43篇
  1991年   20篇
  1990年   24篇
  1989年   25篇
  1988年   34篇
  1987年   17篇
  1986年   20篇
  1985年   15篇
  1984年   17篇
  1983年   6篇
  1982年   6篇
  1981年   6篇
  1980年   13篇
  1979年   1篇
  1978年   3篇
  1977年   1篇
  1976年   1篇
  1971年   1篇
排序方式: 共有5156条查询结果,搜索用时 15 毫秒
1.
2.

Introduction

The objective of this article is to present the rationale and baseline results for a randomized controlled pilot trial using economic incentives to reduce HIV and sexually transmitted infection (STI) risk among male sex workers (MSWs) in Mexico City.

Methods

Participants (n=267) were tested and treated for STIs (chlamydia, gonorrhoea, syphilis and HIV) and viral hepatitis (hepatitis B and C), received HIV and STI prevention education and were randomized into four groups: (1) control, (2) medium conditional incentive ($50/six months), (3) high conditional incentive ($75/six months) and (4) unconditional incentive ($50/six months). In the conditional arms, incentives were contingent upon testing free of new curable STIs (chlamydia, gonorrhoea and syphilis) at follow-up assessments.

Results

Participants’ mean age was 25 years; 8% were homeless or lived in a shelter, 16% were unemployed and 21% lived in Mexico City less than 5 years. At baseline, 38% were living with HIV, and 32% tested positive for viral hepatitis or at least one STI (other than HIV). Participants had a mean of five male clients in the previous week; 18% reported condomless sex with their last client. For 37%, sex work was their main occupation and was conducted mainly on the streets (51%) or in bars/discotheques (24%) and hotels (24%). The average price for a sex transaction was $25 with a 35% higher payment for condomless sex.

Conclusions

The findings suggest that economic incentives are a relevant approach for HIV prevention among MSWs, given the market-based inducements for unprotected sex. This type of targeted intervention seems to be justified and should continue to be explored in the context of combination prevention efforts.  相似文献   
3.
Karasek's job demands–control (JDC) model posits that job control can buffer against the harmful effects of demands experienced by employees. A large volume of JDC research has obtained support for the main effects of demands and control, but not the interactive effects. Recent research on the challenge–hindrance stressors framework, however, found that work stressors may not always be deleterious, suggesting alternative hypotheses about the effects of demands and control. The present study therefore examined competing hypotheses concerning the effects of job demands on occupational health outcomes. Using a sample of 316 employees in a Chinese manufacturing company, we found that, consistent with the challenge–hindrance framework, production demands were challenge stressors associated with favourable outcomes (i.e. job satisfaction and psychological well‐being). In addition, results showed that the interactive role of job control depended on the nature of outcome variables. Future recommendations and implications of findings are discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
4.
Background: Work accidents (WA) due to percutaneous or mucocutaneous injury are frequent among health professionals. Accident notification ensures compliance with legal requirements, enabling health institutions to develop, implement and evaluate prevention strategies. This study aimed to estimate the proportion of underreporting of work accidents caused by percutaneous and mucocutaneous lesions in a hospital setting and its determinants. Methods: A self-administered questionnaire was made available to all hospital employees. The multivariate logistic regression models computed age, gender, professional category, and type of service adjusted odds ratios (OR) and 95% confidence intervals (95% CI). Results: Underreporting of WA associated with biological risk factors was high, particularly in accidents by mucocutaneous injury (80.9%). Physicians were the professional category that least reported this type of work accident (OR=4.64; 95% CI2.20-9.78). The main determinants of underreporting were underestimating the risk of transmission and the excessive bureaucracy. Conclusion: The underreporting of work accidents associated with biological risk factors was considerable, and it contributes to a high degree of uncertainty on accidents'' characterization.  相似文献   
5.
Background:The rubber processing workers experience various types of musculoskeletal disorders (MSDs) due to awkward postures, repetitive movements, and manual loads etc. Research on MSDs and ergonomic interventions in this area is limited. Therefore, the present systematic review aims to (i) identify various operations done by rubber processing workers and their associated MSDs, (ii) explore the ergonomic intervention and post-intervention study and its impact among the workers, (iii) identify the research gaps in MSDs and ergonomic interventions through bibliometric analysis.Methods:Comprehensive electronic searches were conducted in Web of Science, ScienceDirect and PubMed for the search term “Ergonomics” or “Musculoskeletal disorder” and “Rubber” for the article published before 2020. Eleven papers were identified for the review of MSDs and ergonomic interventions; data were extracted to summarize sample size, data collection methods, analyzing tools, various operations, MSDs, and ergonomic interventions.Results:The reviewed article is classified according to various operations such as rubber tapping, latex collection, rubber sheeting and sheet pressing. The review reveals that most of the workers experience lower back pain, which involved a traditional way of operating. Every author is trying to recommend some interventions, but post-intervention studies are limited.Conclusions:Due to the limited post-intervention study, there is a scope of ergonomic interventions in every operation. So, the implementation of a proper ergonomic tool with adequate awareness improves the MSDs among the rubber processing workers. The review will help to identify the various intervention gaps in different operations associated with rubber farming.  相似文献   
6.
AimThe study aimed to describe the finger dexterity in office workers of an Asian population.MethodsOne hundred twenty-seven right-handed office workers, aged 21–50 with a similar split of male and female, were recruited with finger dexterity measured by the O’Connor Finger Dexterity Test. The grip strength, tip and lateral pinch strength of both hands were also measured.ResultsThis study provided the percentile score of the O’Connor Finger Dexterity Test of both males and females in the Asian population. Raw scores of below 218 and 213 seconds in male and female participants respectively reach the 90th percentile, and above 237 and 235 seconds in male and female below the 10th percentile. Results showed no significant difference in local mean scores across different age groups, between male and female and with varying hours of working in typing, filing, and writing. A significant difference was only found in finger dexterity and years of working as office workers. No significant correlation was found between the finger dexterity with grip strength, tip and lateral pinch of the dominant right hand. The results were similar to the original normative score with similar work skills and demands.ConclusionThe mean scores could be used as a valid reference for local occupational therapists to evaluate the finger dexterity of office workers. However, caution has to be taken that conclusions drawn can be biased because of the relatively small sample size, and the results cannot be generalized to represent a wider Asian population.  相似文献   
7.
SETTING:Children and adolescents with HIV encounter challenges in initiation and adherence to antiretroviral therapy (ART). A community-based support intervention of structured home visits, aimed at improving initiation, adherence and treatment, was delivered by community health workers (CHWs) to children and adolescents newly diagnosed with HIV.OBJECTIVES:To 1) describe intervention delivery, 2) explore CHW, caregiver and adolescents’ perceptions of the intervention, 3) identify barriers and facilitators to implementation, and 4) ascertain treatment outcomes at 12 months’ post-HIV diagnosis.DESIGN:We drew upon: 1) semi-structured interviews (n = 22) with 5 adolescents, 11 caregivers and 6 CHWs, 2) 28 CHW field manuals, and 3) quantitative data for study participants (demographic information and HIV clinical outcomes).RESULTS:Forty-one children received at least a part of the intervention. Of those whose viral load was tested, 26 (n = 32, 81.3%) were virally suppressed. Interviewees felt that the intervention supported ART adherence and strengthened mental health. Facilitators to intervention delivery were convenience and rapport between CHWs and families. Stigma, challenges in locating participants and inadequate resources for CHWs were barriers.CONCLUSION:This intervention was helpful in supporting HIV treatment adherence among adolescents and children. Facilitators and barriers may be useful in developing future interventions.  相似文献   
8.
9.
The objective of this study was to estimate solid cancer risk attributable to long‐term, fractionated occupational exposure to low doses of ionizing radiation. Based on cancer incidence for the period 1950–1995 in a cohort of 27,011 Chinese medical diagnostic X‐ray workers and a comparison cohort of 25,782 Chinese physicians who did not use X‐ray equipment in their work, we used Poisson regression to fit excess relative risk (ERR) and excess absolute risk (EAR) dose–response models for incidence of all solid cancers combined. Radiation dose reconstruction was based on a previously published method that relied on simulating measurements for multiple X‐ray machines, workplaces and working conditions, information about protective measures, including use of lead aprons, and work histories. The resulting model was used to estimate calendar year‐specific badge dose calibrated as personal dose equivalent (Sv). To obtain calendar year‐specific colon doses (Gy), we applied a standard organ conversion factor. A total of 1,643 cases of solid cancer were identified in 1.45 million person‐years of follow‐up. In both ERR and EAR models, a statistically significant radiation dose–response relationship was observed for solid cancers as a group. Averaged over both sexes, and using colon dose as the dose metric, the estimated ERR/Gy was 0.87 (95% CI: 0.48, 1.45), and the EAR was 22 per 104PY‐Gy (95% CI: 14, 32) at age 50. We obtained estimates of the ERR and EAR of solid cancers per unit dose that are compatible with those derived from other populations chronically exposed to low dose‐rate occupational or environmental radiation.  相似文献   
10.
The COVID-19 outbreak has led to a focus by public health practitioners and scholars on ways to limit spread while facing unprecedented challenges and resource constraints. Recent COVID-19-specific enhanced Traffic Control Bundling (eTCB) recommendations provide a cogent framework for managing patient care pathways and reducing health care worker (HCW) and patient exposure to SARS-CoV-2. eTCB has been applied broadly and has proven to be effective in limiting fomite and droplet transmissions in hospitals and between hospitals and the surrounding community. At the same time, resource constrained conditions involving limited personal protective equipment (PPE), low testing availability, and variability in physical space can require modifications in the way hospitals implement eTCB. While eTCB has come to be viewed as a standard of practice, COVID-19 related resource constraints often require hospital implementation teams to customize eTCB solutions. We provide and describe a cross-functional, collaborative on-the-ground adaptive application of eTCB initially piloted at two hospitals and subsequently reproduced at 16 additional hospitals and health systems in the US to date. By effectively facilitating eTCB deployment, hospital leaders and practitioners can establish clearer ‘zones of risk’ and related protective practices that prevent transmission to HCWs and patients. We outline key insights and recommendations gained from recent implementation under the aforementioned constraints and a cross-functional team process that can be utilized by hospitals to most effectively adapt eTCB under resource constraints.  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