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   8367篇
  免费   556篇
  国内免费   71篇
耳鼻咽喉   21篇
儿科学   188篇
妇产科学   82篇
基础医学   831篇
口腔科学   121篇
临床医学   850篇
内科学   1004篇
皮肤病学   63篇
神经病学   260篇
特种医学   145篇
外科学   381篇
综合类   1039篇
预防医学   2660篇
眼科学   42篇
药学   779篇
  7篇
中国医学   392篇
肿瘤学   129篇
  2023年   126篇
  2022年   245篇
  2021年   311篇
  2020年   282篇
  2019年   299篇
  2018年   260篇
  2017年   228篇
  2016年   216篇
  2015年   249篇
  2014年   610篇
  2013年   642篇
  2012年   618篇
  2011年   706篇
  2010年   559篇
  2009年   463篇
  2008年   404篇
  2007年   383篇
  2006年   314篇
  2005年   259篇
  2004年   266篇
  2003年   231篇
  2002年   163篇
  2001年   112篇
  2000年   92篇
  1999年   77篇
  1998年   61篇
  1997年   69篇
  1996年   39篇
  1995年   54篇
  1994年   61篇
  1993年   31篇
  1992年   40篇
  1991年   34篇
  1990年   22篇
  1989年   27篇
  1988年   27篇
  1987年   21篇
  1986年   26篇
  1985年   37篇
  1984年   53篇
  1983年   22篇
  1982年   28篇
  1981年   19篇
  1980年   34篇
  1979年   19篇
  1978年   22篇
  1976年   20篇
  1975年   19篇
  1974年   25篇
  1973年   17篇
排序方式: 共有8994条查询结果,搜索用时 0 毫秒
101.

Objective

Examine existing reviews of patient engagement methods to propose a model where the focus is on engaging patients in clinical workflows, and to assess the feasibility of advocated patient engagement methods.

Methods

A literature search of reviews of patient engagement methods was conducted. Included reviews were peer-reviewed, written in English, and focused on methods that targeted patients or patient–provider dyads. Methods were categorized to propose a conceptual model. The feasibility of methods was assessed using an adapted rating system.

Results

We observed that we could categorize patient engagement methods based on information provision, patient activation, and patient–provider collaboration. Methods could be divided by high and low feasibility, predicated on the extent of extra work required by the patient or clinical system. Methods that have good fit with existing workflows and that require proportional amounts of work by patients are likely to be the most feasible.

Conclusion

Implementation of patient engagement methods is likely to depend on finding a “sweet-spot” where demands required by patients generate improved knowledge and motivate active participation.

Practice implications

Attention should be given to those interventions and methods that advocate feasibility with patients, providers, and organizational workflows.  相似文献   
102.
A thorough understanding of the EEG signal and its measurement is necessary to produce high quality data and to draw accurate conclusions from those data. However, publications that discuss relevant topics are written for divergent audiences with specific levels of expertise: explanations are either at an abstract level that leaves readers with a fuzzy understanding of the electrophysiology involved, or are at a technical level that requires mastery of the relevant physics to understand. A clear, comprehensive review of the origin and measurement of EEG that bridges these high and low levels of explanation fills a critical gap in the literature and is necessary for promoting better research practices and peer review. The present paper addresses the neurophysiological source of EEG, propagation of the EEG signal, technical aspects of EEG measurement, and implications for interpretation of EEG data.  相似文献   
103.
104.
105.
Synthetic cathinones are new psychoactive substances that represent a health risk worldwide.For most of the 130 reported compounds,information about toxicology and/or metabolism is not available,which hampers their detection(and subsequent medical treatment)in intoxication cases.The principles of forensic analytical chemistry and the use of powerful analytical techniques are indispensable for stab-lishing the most appropriate biomarkers for these substances.Human metabolic fate of synthetic cathinones can be assessed by the analysis of urine and blood obtained from authentic consumers;however,this type of samples is limited and difficult to access.In this work,the metabolic behaviour of three synthetic cathinones(4-CEC,4-CPrC and 5-PPDi)and one amphetamine(3-FEA)has been evalu-ated by incubation with pooled human hepatocytes and metabolite identification has been performed by high-resolution mass spectrometry.This in vitro approach has previously shown its feasibility for obtaining excretory human metabolites.4-CEC and 3-FEA were not metabolised,and for 4-CPrC only two minor metabolites were obtained.On the contrary,for the recently reported 5-PPDi,twelve phase I metabolites were elucidated.Up to our knowledge,this is the first metabolic study of an indanyl-cathinone.Data reported in this paper will allow the detection of these synthetic stimulants in intoxi-cation cases,and will facilitate future research on the metabolic behaviour of other indanyl-based cathinones.  相似文献   
106.
A simple inexpensive trap (Esperanza window trap) was shown recently to collect significant numbers of Simulium ochraceum sensu lato, a major vector of Onchocerca volvulus in Mesoamerica. Here, we report studies optimizing this trap for the collection of Simulium damnosum s.l., the major vector of O. volvulus in Africa. A shortened, blue and black striped version of the Esperanza window trap, when baited with a combination of CO2 and worn trousers, rivalled human landing collections in the number of S. damnosum s.l. females collected. Traps baited with a commercially available human skin lure and CO2 resulted in collections that were not significantly different than those obtained from traps baited with worn trousers and CO2. This suggests that the Esperanza window trap may offer a replacement for human landing collections for monitoring onchocerciasis transmission in Africa.  相似文献   
107.
108.
109.
Objective: To identify approximately 500 cases of incident cognitive impairment (ICI) in a large, national sample adapting an existing cognitive test-based case definition and to examine relationships of vascular risk factors with ICI. Method: Participants were from the REGARDS study, a national sample of 30,239 African-American and White Americans. Participants included in this analysis had normal cognitive screening and no history of stroke at baseline, and at least one follow-up cognitive assessment with a three-test battery (TTB). Regression-based norms were applied to TTB scores to identify cases of ICI. Logistic regression was used to model associations with baseline vascular risk factors. Results: We identified 495 participants with ICI of 17,630 eligible participants. In multivariable modeling, income (OR 1.83 CI 1.27,2.62), stroke belt residence (OR 1.45 CI 1.18,1.78), history of transient ischemic attack (OR 1.90 CI 1.29,2.81), coronary artery disease(OR 1.32 CI 1.02,1.70), diabetes (OR 1.48 CI 1.17,1.87), obesity (OR 1.40 CI 1.05,1.86), and incident stroke (OR 2.73 CI 1.52,4.90) were associated with ICI. Conclusions: We adapted a previously validated cognitive test-based case definition to identify cases of ICI. Many previously identified risk factors were associated with ICI, supporting the criterion-related validity of our definition.  相似文献   
110.
Preterm infants often experience hyperoxia while receiving supplemental oxygen. Prolonged exposure to hyperoxia during development is associated with pathologies such as bronchopulmonary dysplasia and retinopathy of prematurity. Over the last 25 years, however, experiments with animal models have revealed that moderate exposures to hyperoxia (e.g., 30–60% O2 for days to weeks) can also have profound effects on the developing respiratory control system that may lead to hypoventilation and diminished responses to acute hypoxia. This plasticity, which is generally inducible only during critical periods of development, has a complex time course that includes both transient and permanent respiratory deficits. Although the molecular mechanisms of hyperoxia-induced plasticity are only beginning to be elucidated, it is clear that many of the respiratory effects are linked to abnormal morphological and functional development of the carotid body, the principal site of arterial O2 chemoreception for respiratory control. Specifically, developmental hyperoxia reduces carotid body size, decreases the number of chemoafferent neurons, and (at least transiently) diminishes the O2 sensitivity of individual carotid body glomus cells. Recent evidence suggests that hyperoxia may also directly or indirectly impact development of the central neural control of breathing. Collectively, these findings emphasize the vulnerability of the developing respiratory control system to environmental perturbations.  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