全文获取类型
收费全文 | 6999篇 |
免费 | 1050篇 |
国内免费 | 42篇 |
专业分类
耳鼻咽喉 | 44篇 |
儿科学 | 165篇 |
妇产科学 | 170篇 |
基础医学 | 803篇 |
口腔科学 | 184篇 |
临床医学 | 1620篇 |
内科学 | 969篇 |
皮肤病学 | 24篇 |
神经病学 | 643篇 |
特种医学 | 126篇 |
外科学 | 626篇 |
综合类 | 402篇 |
一般理论 | 2篇 |
预防医学 | 1521篇 |
眼科学 | 29篇 |
药学 | 304篇 |
4篇 | |
中国医学 | 56篇 |
肿瘤学 | 399篇 |
出版年
2024年 | 15篇 |
2023年 | 196篇 |
2022年 | 234篇 |
2021年 | 424篇 |
2020年 | 423篇 |
2019年 | 492篇 |
2018年 | 444篇 |
2017年 | 436篇 |
2016年 | 356篇 |
2015年 | 413篇 |
2014年 | 511篇 |
2013年 | 587篇 |
2012年 | 407篇 |
2011年 | 320篇 |
2010年 | 302篇 |
2009年 | 305篇 |
2008年 | 318篇 |
2007年 | 268篇 |
2006年 | 254篇 |
2005年 | 198篇 |
2004年 | 165篇 |
2003年 | 149篇 |
2002年 | 103篇 |
2001年 | 99篇 |
2000年 | 113篇 |
1999年 | 70篇 |
1998年 | 82篇 |
1997年 | 60篇 |
1996年 | 38篇 |
1995年 | 36篇 |
1994年 | 38篇 |
1993年 | 35篇 |
1992年 | 36篇 |
1991年 | 30篇 |
1990年 | 21篇 |
1989年 | 11篇 |
1988年 | 17篇 |
1987年 | 12篇 |
1986年 | 10篇 |
1985年 | 14篇 |
1984年 | 6篇 |
1983年 | 9篇 |
1982年 | 10篇 |
1981年 | 9篇 |
1980年 | 5篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有8091条查询结果,搜索用时 31 毫秒
21.
Semi-structured interviews were conducted with a cohort of 22 test applicants who requested Huntington's disease (HD) predictive testing in South Wales, and a random sample of 32 non-requesters, drawn from the South Wales HD register. Apart from identifying differences between the groups, the study afforded the opportunity to listen, at length, to at-risk individuals' accounts of living at risk and their thoughts about predictive testing and genetic services. Emergent themes included difficulties in family communication and the uncertainties inherent in being at risk and undergoing testing. Important factors in decision making about testing were: moral imperatives to clarify one's genetic status; views about the controllability of the future; family attitudes and norms; and the impact of a test result on family members. At-risk individuals' perceptions of the genetics service were that contact with the service would result in pressure to be tested and a need for test applicants to present a favourable view of coping capacities to secure testing. In addition, there was an expectation of ongoing contact with HD families at the initiative of the service providers. Implications of the findings for the way in which predictive testing services are structured and introduced to the at-risk population are discussed. 相似文献
22.
PETER M SCALLY 《Journal of Medical Imaging and Radiation Oncology》1993,37(4):336-341
Radiology can be more interesting if the principles of decision making are understood and used to the advantage of the radiologist, referring clinician and patient. This article seeks to revise the principles that radiologists use intuitively. Particular emphasis is placed on the importance of the pre-test probability, as it can be shown to: (i) vary with the referral pool of patients; (ii) be a major determinant of the amount of additional information gained from the test; (iii) alter the sensitivity and specificity of the test; and (iv) determine largely the significance of a positive or negative test result. An investigation helps a clinician by providing information that will move the probability of disease above an action threshold or below its exclusion threshold. If this does not occur as a result of one study, another is selected. This article also describes the factors involved in such a decision tree analysis, as well as discussing the reasons for both selecting a particular examination and deciding when a test should not be performed. 相似文献
23.
24.
The effectiveness of organizational interventions in reducing the adverse consequences of work–family conflict has produced mixed findings. This paper examines the relationship between the use of organizational ‘family friendly’ resources (such as crèche facilities, flexible working hours, and job sharing), with levels of work–family conflict, and job and family satisfaction over time. Using structural equation modelling, these associations were tested in 398 employed men and women who each completed a self‐report questionnaire administered on two occasions. The use of organizational interventions directly predicted increased levels of concurrent (Time 1) work–family interference and increased levels of subsequent (Time 2) job satisfaction. Both organizational interventions and family interventions (i.e. support) positively predicted subsequent family satisfaction. The research demonstrates that the provision of organizational ‘family‐friendly’ practices will produce improved psychological outcomes for employees. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
25.
Decisions about which health-care interventions represent adequate value to collectively funded health-care systems are as widespread as they are unavoidable. In the case of new pharmaceuticals, many countries now require formal cost-effectiveness analysis to inform this decision-making process. This requires evidence on parameters associated with health-related utilities, treatment effects, resource use, and costs, for which data from available regulatory trials are invariably absent or highly uncertain. This uncertainty results from a number of factors including the predominance of intermediate end points in the clinical evidence-base and the limited period of follow-up of patients in clinical studies. Despite these imperfections in the evidence base, decisions about whether new pharmaceuticals are sufficiently cost-effective for reimbursement cannot be side-stepped. Data limitations do, however, require the use of rigorous analytical methods to support decision making. Probabilistic decision models and value of information analysis offer a means of structuring decision problems, synthesizing all available data, characterizing the uncertainty in the decision, quantifying the cost of uncertainty, and establishing the expected value of perfect information. This analytical framework is important because it addresses two fundamental questions about new pharmaceuticals. First, is the product expected to be cost-effective on the basis of existing evidence? Second, is additional research concerning the product itself cost-effective? In addressing these questions, the analytical framework can establish when sufficient evidence exists to sustain a claim for a new pharmaceutical to be cost-effective. 相似文献
26.
B. B. Robbie Rossman Mindy S. Rosenberg 《Journal of child psychology and psychiatry, and allied disciplines》1992,33(4):699-715
While factors such as gender and SES have been studied as moderators of stress for children, their perceptions of control have received little attention. In the current study, children's domain-specific perceptions of their control during marital conflict were investigated as potential moderators of the impact of family stress on children's behavior problems, and perceptions of competence. Ninety-four children aged 6-12 years and mothers from families ranging in level of parental conflict from nondiscordant to discordant to physically violent were interviewed. Multiple regression analyses revealed that higher levels of conflict control beliefs acted as compensatory moderators of stress, being associated with lower levels of problem behaviors across stress levels. However, higher conflict control beliefs acted as vulnerability moderators with regard to children's perceptions of competence. 相似文献
27.
28.
29.
30.
Michael S. Runyon MD Peter B. Richman MD Jeffrey A. Kline MD 《Academic emergency medicine》2007,14(1):53-57
Background Several clinical decision rules (CDRs) have been validated for pretest probability assessment of pulmonary embolism (PE), but the authors are unaware of any data quantifying and characterizing their use in emergency departments. Objectives To characterize clinicians' knowledge of and attitudes toward two commonly used CDRs for PE. Methods By using a modified Delphi approach, the authors developed a two‐page paper survey including 15 multiple‐choice questions. The questions were designed to determine the respondents' familiarity, frequency of use, and comprehension of the Canadian and Charlotte rules. The survey also queried the frequency of use of unstructured (gestalt) pretest probability assessment and reasons why physicians choose not to use decision rules. The surveys were sent to physicians, physician assistants, and medical students at 32 academic and community hospitals in the United States and the United Kingdom. Results Respondents included 555 clinicians; 443 (80%) work in academic practice, and 112 (20%) are community based. Significantly more academic practitioners (73%) than community practitioners (49%) indicated familiarity with at least one of the two decision rules. Among all respondents familiar with a rule, 50% reported using it in more than half of applicable cases. A significant number of these respondents could not correctly identify a key component of the rule (23% for the Charlotte rule and 43% for the Canadian rule). Fifty‐seven percent of all respondents indicated use of gestalt rather than a decision rule in more than half of cases. Conclusions Academic clinicians were more likely to report familiarity with either of these two specific decision rules. Only one half of all clinicians reporting familiarity with the rules use them in more than 50% of applicable cases. Spontaneous recall of the specific elements of the rules was low to moderate. Future work should consider clinical gestalt in the evaluation of patients with possible PE. 相似文献