全文获取类型
收费全文 | 1504篇 |
免费 | 169篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 17篇 |
妇产科学 | 27篇 |
基础医学 | 161篇 |
口腔科学 | 25篇 |
临床医学 | 147篇 |
内科学 | 293篇 |
皮肤病学 | 7篇 |
神经病学 | 56篇 |
特种医学 | 68篇 |
外科学 | 279篇 |
综合类 | 72篇 |
一般理论 | 1篇 |
预防医学 | 285篇 |
眼科学 | 38篇 |
药学 | 90篇 |
肿瘤学 | 106篇 |
出版年
2021年 | 17篇 |
2020年 | 18篇 |
2019年 | 24篇 |
2018年 | 22篇 |
2017年 | 25篇 |
2016年 | 30篇 |
2015年 | 22篇 |
2014年 | 39篇 |
2013年 | 48篇 |
2012年 | 63篇 |
2011年 | 83篇 |
2010年 | 40篇 |
2009年 | 38篇 |
2008年 | 55篇 |
2007年 | 54篇 |
2006年 | 61篇 |
2005年 | 61篇 |
2004年 | 72篇 |
2003年 | 53篇 |
2002年 | 66篇 |
2001年 | 49篇 |
2000年 | 42篇 |
1999年 | 44篇 |
1998年 | 22篇 |
1997年 | 15篇 |
1996年 | 14篇 |
1995年 | 17篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 35篇 |
1991年 | 38篇 |
1990年 | 24篇 |
1989年 | 34篇 |
1988年 | 28篇 |
1987年 | 35篇 |
1986年 | 32篇 |
1985年 | 42篇 |
1984年 | 36篇 |
1983年 | 26篇 |
1982年 | 25篇 |
1981年 | 15篇 |
1979年 | 20篇 |
1978年 | 20篇 |
1977年 | 14篇 |
1976年 | 13篇 |
1975年 | 10篇 |
1974年 | 14篇 |
1973年 | 9篇 |
1972年 | 11篇 |
1970年 | 13篇 |
排序方式: 共有1674条查询结果,搜索用时 15 毫秒
991.
Firmstone VR Bullock AD Fielding A Frame JW Gibson C Hall J 《British dental journal》2004,196(12):773-777
INTRODUCTION: This paper reports the impact of course attendance on the practice of dentists. METHOD: Phase One: A survey sent to all general dental practitioners (GDPs) in three deaneries in England. The survey included self-ratings of the impact of course attendance on practice. Phase Two: Interviews with 20 dentists before and two to three months after they had participated in a self-selected course. The response rate to the survey was 54% (n = 2082). Comparisons with national data showed no notable bias in the sample for gender, owners/partners and age/experience. An ordered logit model was used to explore the net effect of factors (including years' experience in general dental practice and gender) on dentists' ratings of course impact. RESULTS: Course attendance was judged to impact on practice. Impact rating was affected by participation rate and years' experience. Barriers to implementation included cost, time, NHS constraints and personal or staff issues. Impact was enhanced when selection of courses was based on learning needs although courses may also serve usefully to confirm current practice. CONCLUSION: There is much that dentists themselves can do to enhance the impact of courses, principally by reflecting on learning needs. They should be supported in the development of personal learning plans. 相似文献
992.
993.
Kim-Farley RJ Celentano JT Gunter C Jones JW Stone RA Aller RD Mascola L Grigsby SF Fielding JE 《Prehospital and disaster medicine》2003,18(4):313-320
The smallpox virus is a high-priority, Category-A agent that poses a global, terrorism security risk because it: (1) easily can be disseminated and transmitted from person to person; (2) results in high mortality rates and has the potential for a major public health impact; (3) might cause public panic and social disruption; and (4) requires special action for public health preparedness. In recognition of this risk, the Los Angeles County Department of Health Services (LAC-DHS) developed the Smallpox Preparedness, Response, and Recovery Plan for LAC to prepare for the possibility of an outbreak of smallpox. A unique feature of the LAC-DHS plan is its explicit use of the Standardized Emergency Management System (SEMS) framework for detailing the functions needed to respond to a smallpox emergency. The SEMS includes the Incident Command System (ICS) structure (management, operations, planning/intelligence, logistics, and finance/administration), the mutual-aid system, and the multi/interagency coordination required during a smallpox emergency. Management for incident command includes setting objectives and priorities, information (risk communications), safety, and liaison. Operations includes control and containment of a smallpox outbreak including ring vaccination, mass vaccination, adverse events monitoring and assessment, management of confirmed and suspected smallpox cases, contact tracing, active surveillance teams and enhanced hospital-based surveillance, and decontamination. Planning/intelligence functions include developing the incident action plan, epidemiological investigation and analysis of smallpox cases, and epidemiological assessment of the vaccination coverage status of populations at risk. Logistics functions include receiving, handling, inventorying, and distributing smallpox vaccine and vaccination clinic supplies; personnel; transportation; communications; and health care of personnel. Finally, finance/administration functions include monitoring costs related to the smallpox emergency, procurement, and administrative aspects that are not handled by other functional divisions of incident command systems. The plan was developed and is under frequent review by the LAC-DHS Smallpox Planning Working Group, and is reviewed periodically by the LAC Bioterrorism Advisory Committee, and draws upon the Smallpox Response Plan and Guidelines of the Centers for Disease Control and Prevention (CDC) and recommendations of the Advisory Committee on Immunization Practices (ACIP). The Smallpox Preparedness, Response, and Recovery Plan, with its SEMS framework and ICS structure, now is serving as a model for the development of LAC-DHS plans for responses to other terrorist or natural-outbreak responses. 相似文献
994.
995.
996.
Maxwell-Armstrong CA Durrant LG Buckley TJ Scholefield JH Robins RA Fielding K Monson JR Guillou P Calvert H Carmichael J Hardcastle JD 《British journal of cancer》2001,84(11):1443-1446
The cancer vaccine 105AD7 is an anti-idiotypic monoclonal antibody that mimics the tumour-associated antigen 791T/gp72 (CD55, Decay Accelerating Factor) on colorectal cancer cells. Phase I studies in patients with advanced disease confirmed that 105AD7 is non-toxic, and that T cell responses could be generated. A prospective, randomized, double-blind, placebo-controlled survival study in patients with advanced colorectal cancer was performed. 162 patients were enrolled between April 1994 and October 1996. Patients attended at trial entry, and at 6 and 12 weeks, where they received 105AD7 or placebo. Study groups were comparable in terms of patient demographics, and time from diagnosis of advanced colorectal cancer (277.1 v 278.6 days). Baseline disease was similar, with 50% of patients having malignancy in at least 2 anatomic sites. Compliance with treatment was poor, with only 50% of patients receiving 3 planned vaccinations. Median survival from randomization date was 124 and 184 days in 105AD7 and placebo arms respectively (P = 0.38), and 456 and 486 days from the date of diagnosis of advanced disease (P = 0.82). 105AD7 vaccination does not prolong survival in patients with advanced colorectal cancer. The reasons for lack of efficacy are unclear, but may reflect the high tumour burden in the patient population, and poor compliance with immunization. Further vaccine studies should concentrate on patients with minimal residual disease. 相似文献
997.
Roche P Krause V Cook H Bartlett M Coleman D Davis C Fielding J Giele C Gilmour R Holland R Kampen R;Enhanced Invasive Pneumococcal Diseases Surveillance Working Group 《Communicable diseases intelligence》2007,31(1):86-100
Enhanced surveillance for invasive pneumococcal disease (IPD) was carried out in all Australian states and territories in 2005 with comparative data available since 2001. There were 1,680 cases of IPD notified to the National Notifiable Diseases Surveillance System in Australia in 2005; a notification rate of 8.3 cases per 100,000 population. The rates varied between states and territories and by geographical region with the highest rates in the Northern Territory, the jurisdiction with the largest proportion of Indigenous people. Invasive pneumococcal disease was reported most frequently in those aged 85 years or over (41 cases per 100,000 population) and in 1-year-old children (36.5 cases per 100,000 population). Enhanced data provided additional information on 1,015 (60%) of all notified cases. The overall rate of IPD in Indigenous Australians was 8.6 times the rate in non-Indigenous Australians. There were 126 deaths attributed to IPD resulting in an overall case fatality rate of 7.5%. While the rate of IPD in the Indigenous under 2-year-old population decreased from 219 cases per 100,000 population since targeted introduction of the 7-valent conjugate pneumococcal vaccine (7vPCV) in 2001, the rate in 2005 (94 cases per 100,000 population) was significantly greater than in non-Indigenous children (20.4 cases per 100,000 population). Rates of disease in all children aged less than 2 years, caused by serotypes in the 7vPCV decreased by 75% between 2004 and 2005 as a result of the introduction of a universal childhood 7vPCV immunisation program. Significant decreases in IPD caused by 7vPCV serotypes also occurred in the 2-14 years and 65 years or over age groups. There is no evidence of replacement disease with non-vaccine serotypes. Serotypes were identified in 90% of all notified cases, with 61% of disease caused by serotypes in the 7vPCV and 88% caused by serotypes in the 23-valent polysaccharide pneumococcal vaccine (23vPPV). Reduced penicillin susceptibility remains low and reduced susceptibility to 3rd generation cephalosporins is rare. 相似文献
998.
Elsa Dent J. E. Morley A. J. Cruz-Jentoft H. Arai S. B. Kritchevsky J. Guralnik J. M. Bauer M. Pahor B. C. Clark M. Cesari J. Ruiz C. C. Sieber M. Aubertin-Leheudre D. L. Waters R. Visvanathan F. Landi D. T. Villareal R. Fielding C. W. Won O. Theou F. C. Martin B. Dong J. Woo L. Flicker L. Ferrucci R. A. Merchant L. Cao T. Cederholm S. M. L. Ribeiro L. Rodríguez-Mañas S. D. Anker L. M. Gutiérrez Robledo I. Bautmans I. Aprahamian J. M. G. A. Schols M. Izquierdo B. Vellas 《The journal of nutrition, health & aging》2018,22(10):1148-1161
999.
Alice Grady Kirsty Seward Meghan Finch Alison Fielding Fiona Stacey Jannah Jones Luke Wolfenden Sze Lin Yoong 《Journal of nutrition education and behavior》2018,50(3):229-237.e1
Objective
To identify perceived barriers and enablers to implementation of dietary guidelines reported by early childhood education center cooks, and barriers and enablers associated with greater implementation based on assessment of center menu compliance.Design
Cross-sectional telephone interview.Setting
Early childhood education centers, New South Wales, Australia.Participants
A total of 202 cooks responsible for menu planning; 70 centers provided a menu for review of compliance with dietary guidelines.Main Outcome Measure
Barriers and enablers to dietary guideline implementation were determined using a tool assessing constructs of the Theoretical Domains Framework (TDF). Higher scores (≥6) for each construct indicated enablers to guideline implementation; lower scores (<6) suggested barriers.Analysis
Multivariable linear regression identified TDF constructs associated with greater guideline implementation.Results
Scores were lowest for reinforcement (mean, 5.85) and goals (mean, 5.89) domains, and highest for beliefs about consequences (mean, 6.51) and social/professional role and identity (mean, 6.50). The skills domain was positively associated with greater implementation of guidelines based on menu review (P?=?.01).Conclusions and Implications
Cooks perceived social/professional role and identity, and beliefs about consequences to be enablers to dietary guideline implementation; however, only the skills domain was associated with greater implementation. There are opportunities to target the incongruence in perceptions vs reality of the barriers and enablers to implementation. Future research could examine the utility of the TDF to identify barriers and enablers to implementation to inform intervention development and for evaluating interventions to examine intervention mechanisms. 相似文献1000.
In stepped‐wedge trials (SWTs), the intervention is rolled out in a random order over more than 1 time‐period. SWTs are often analysed using mixed‐effects models that require strong assumptions and may be inappropriate when the number of clusters is small. We propose a non‐parametric within‐period method to analyse SWTs. This method estimates the intervention effect by comparing intervention and control conditions in a given period using cluster‐level data corresponding to exposure. The within‐period intervention effects are combined with an inverse‐variance‐weighted average, and permutation tests are used. We present an example and, using simulated data, compared the method to (1) a parametric cluster‐level within‐period method, (2) the most commonly used mixed‐effects model, and (3) a more flexible mixed‐effects model. We simulated scenarios where period effects were common to all clusters, and when they varied according to a distribution informed by routinely collected health data. The non‐parametric within‐period method provided unbiased intervention effect estimates with correct confidence‐interval coverage for all scenarios. The parametric within‐period method produced confidence intervals with low coverage for most scenarios. The mixed‐effects models' confidence intervals had low coverage when period effects varied between clusters but had greater power than the non‐parametric within‐period method when period effects were common to all clusters. The non‐parametric within‐period method is a robust method for analysing SWT. The method could be used by trial statisticians who want to emphasise that the SWT is a randomised trial, in the common position of being uncertain about whether data will meet the assumptions necessary for mixed‐effect models. 相似文献