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   12032篇
  免费   1021篇
  国内免费   29篇
耳鼻咽喉   137篇
儿科学   509篇
妇产科学   328篇
基础医学   1631篇
口腔科学   140篇
临床医学   1959篇
内科学   2199篇
皮肤病学   164篇
神经病学   1217篇
特种医学   203篇
外国民族医学   2篇
外科学   892篇
综合类   147篇
一般理论   18篇
预防医学   1870篇
眼科学   176篇
药学   638篇
中国医学   9篇
肿瘤学   843篇
  2024年   20篇
  2023年   144篇
  2022年   169篇
  2021年   365篇
  2020年   282篇
  2019年   423篇
  2018年   430篇
  2017年   370篇
  2016年   335篇
  2015年   376篇
  2014年   479篇
  2013年   719篇
  2012年   970篇
  2011年   965篇
  2010年   538篇
  2009年   448篇
  2008年   754篇
  2007年   817篇
  2006年   736篇
  2005年   643篇
  2004年   614篇
  2003年   568篇
  2002年   537篇
  2001年   94篇
  2000年   54篇
  1999年   61篇
  1998年   109篇
  1997年   79篇
  1996年   75篇
  1995年   65篇
  1994年   63篇
  1993年   41篇
  1992年   46篇
  1991年   56篇
  1990年   33篇
  1989年   43篇
  1988年   33篇
  1987年   31篇
  1986年   24篇
  1985年   24篇
  1984年   27篇
  1983年   24篇
  1982年   28篇
  1981年   24篇
  1980年   30篇
  1978年   14篇
  1977年   15篇
  1976年   26篇
  1975年   19篇
  1974年   17篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
Identifying environmental factors reflected to alcohol use is important for program planning and evaluation in college alcohol and drug prevention programs. Little has been written concerning uses of data in environmental prevention efforts. This paper presents four brief interrelated case studies of how environmental modifications were used by a college alcohol prevention project to 1) change the marketing practices and service policies of a student-oriented bar, 2) alter the sales practices of a campus bookstore concerning alcohol paraphernalia, 3) to develop a campaign with the goal of reducing risk factors related to heavy drinking at private student parties, and 4) stop an unsafe bus from transporting students to bars in Mexico. Creative use of such environmental prevention approaches has potential benefit to colleges and universities concerned with the primary prevention of alcohol-related problems experienced by students.  相似文献   
22.
23.
Stroke rehabilitation is an area of practice that many occupational therapists encounter during their career. The literature promotes a wide range of management techniques and support devices for people who have a stroke-affected upper limb, but little is known about the validity of those that occupational therapists actually use in practice. A questionnaire was sent to occupational therapists working in Queensland and northern New South Wales facilities (n = 35), in which adults with a stroke were likely to be treated. Eighteen respondents answered questions about the management techniques and support devices used in their facility, and their perception of the benefit of these devices in the reduction of hemiplegic shoulder pain. Results are discussed with reference to evidence-based practice and indicate an urgent need for the collation and dissemination of the best current evidence available for the management techniques and support devices used in this area, as well as further research to extend this evidence.  相似文献   
24.

Objective

To estimate the national prevalence of arthritis‐attributable work limitation (AAWL) among persons ages 18–64 with doctor‐diagnosed arthritis and examine correlates of AAWL.

Methods

Using the 2002 National Health Interview Survey, we estimated the prevalence of AAWL (limited in whether individuals work, the type of work they do, or the amount of work they do) and correlates of AAWL in univariable and multivariable‐adjusted logistic regression analyses. Survey data were analyzed in SAS and SUDAAN to account for the complex sample design.

Results

A total of 5.3% of all US adults ages 18–64 reported AAWL; in this age group, AAWL is reported by ~30% of those who report arthritis. The prevalence of AAWL was highest among people ages 45–64 years (10.2%), women (6.3%), non‐Hispanic blacks (7.7%), people with less than a high school education (8.6%), and those with an annual household income <$20,000 (12.6%). AAWL was substantially increased among people with arthritis‐attributable activity limitations (multivariable‐adjusted odds ratio [OR] 9.1, 95% confidence interval [95% CI] 7.1–11.6). The multivariable‐adjusted likelihood of AAWL was moderately higher among non‐Hispanic blacks (OR 1.6, 95% CI 1.2–2.3), Hispanics (OR 1.8, 95% CI 1.2–2.6), and people with high levels of functional/social/leisure limitations (OR 1.8, 95% CI 1.4–2.3) and was decreased among those with a college education (OR 0.6, 95% CI 0.4–0.8).

Conclusion

AAWL is highly prevalent, affecting millions of Americans and one‐third of adults with doctor‐diagnosed arthritis. Findings suggest the need for more targeted research to better understand the natural history, success of interventions, and effects of policy on AAWL. Public health interventions, including self‐management education programs, may be effective in countering AAWL.  相似文献   
25.
The use of mechanical ventilation in the Emergency Department requires adequate resources in order to maintain patient safety and avoid potential risks. Moreover, developments in technology require increased knowledge of mechanical ventilation techniques to address the complexity of decision-making involved. Organisational issues and system factors have the potential to negatively impact on the ability of the emergency service to provide optimum care to patients receiving mechanical ventilation. These issues include staffing and skill-mix, demand on emergency services, role-delineation, scope of practice, and current mechanisms for monitoring of quality and safety. Furthermore, in response to advances in ventilator technology, current education programs for both nursing and medical staff require review to ensure that they provide comprehensive information about the types of ventilation techniques now available and the relative risks and benefits associated with their application.This article is the second in a two-part series and explores the educational and organisational factors that impact upon safety and quality of care delivered to patients receiving mechanical ventilation in the emergency department. Recommendations for future policy development, curriculum review and reporting mechanisms to support further research in the application of mechanical ventilation in the emergency department are made.  相似文献   
26.
Patients with lung cancer experience considerable distress. Therefore, accurate methods for assessing distress and quality of life over time may play a key role for managing and evaluating palliative care. Alternatives to commonly used standardized questionnaires are individual measures. This study prospectively and retrospectively explored the concerns that 46 patients with inoperable lung cancer spontaneously reported as causing most distress close to diagnosis and 6 months later. Changes in content individually generated through a structured inductive freelisting were compared with EORTC-QLQ-C30+LC13 ratings. The results showed that patients perceived a wide variety of concerns as most distressing and that their concerns changed over time. Between 56 and 62% of these concerns were assessed by items included in the EORTC-QLQ-C30+LC13 questionnaires. Furthermore, patients’ reports of most distress from fatigue, pain and dyspnea were not always reflected in intensity ratings of comparable EORTC-QLQ-C30+LC13 items. These results indicate that items included in standardized measures are not always adequate to assess patients’ concerns, priorities and changes over time. In addition to standardized questionnaires, individualized measures may be useful in the clinical palliative setting for providing detailed information about the individual’s problems and prioritizations.  相似文献   
27.
The controlled treatment outcome studies that examined the efficacy of EMDR in the treatment of posttraumatic stress disorder have yielded a range of results, with the efficacy of EMDR varying across studies. The current study sought to determine if differences in outcome were related to methodological differences. The research was reviewed to identify methodological strengths, weaknesses, and empirical findings. The relationships between effect size and methodology ratings were examined, using the Gold Standard (GS) Scale (adapted from Foa & Meadows, 1997). Results indicated a significant relationship between scores on the GS Scale and effect size, with more rigorous studies according to the GS Scale reporting larger effect sizes. There was also a significant correlation between effect size and treatment fidelity. Additional methodological components not detected by the GS Scale were identified, and suggestions were made for a Revised GS Scale. We conclude by noting that methodological rigor removes noise and thereby decreases error measurement, allowing for the more accurate detection of true treatment effects in EMDR studies.  相似文献   
28.
29.
30.
Polycyclic aromatic hydrocarbons (PAHs) demonstrate carcinogenic activity in animal models. Although some epidemiologic studies have implicated PAHs as risk factors for human cancer, the evidence reported to date has not been consistent. The purpose of this report is to describe the associations between occupational exposure to PAHs in the workplace and each of 14 types of cancer. A population-based, case-control study was carried out in Montreal to investigate associations between a large variety of environmental and occupational exposures on the one hand, and several types of cancer on the other. A detailed job history was obtained from each subject along with information on a number of potential confounders. Each job history was reviewed by a team of experts, who used this information to construct a corresponding history of occupational exposures. Among the PAH exposures considered were benzo(a)pyrene (B(a)P) and five categories of PAHs defined on the basis of the source material, namely, wood, petroleum, coal, other sources, and any source. Altogether, 3,730 cancer patients and 533 population controls were interviewed and their job exposure histories coded. For each of 14 types of cancer analyzed, three control groups were available: other cancer patients, population controls, and the pooled set of cancer and population controls. The associations between 14 cancer types and 6 PAH exposures were analyzed using logistic regression methods. For most types of cancer evaluated, there was no evidence of excess risk due to PAHs at the levels encountered in the occupations in which PAH exposure has been prevalent in the Montreal area. For a few cancer sites–the esophagus, the pancreas, and the prostate gland–there were suggestions of excess risk; these observations are noteworthy hypotheses for further investigation. For lung cancer, there appeared to be an increased risk due to PAHs among nonsmokers and light smokers, but not among heavy smokers.  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