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41.
ObjectiveInvestigate the effects of complementary therapies on functional capacity and quality of life among prefrail and frail older adults.Materials and MethodAn electronic search was performed in the PubMed, EMBASE, Web of Science, Cochrane Library, LILACS and PEDro databases for relevant articles published up to September 2019. Only randomized controlled trials with interventions involving complementary therapies for prefrail and frail older adults were included. This review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Cochrane recommendations. The methodological quality of the selected studies was appraised using the PEDro scale and the evidence was synthesized using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) scale.ResultsFifteen studies met the inclusion criteria and were selected for the present review. Six different complementary therapies were identified and the main findings were related to Tai Chi. A very low to moderate level of evidence was found regarding the effectiveness of Tai Chi in terms a functional capacity (balance, mobility, gait speed, functional reach and lower limb muscle strength) and a low level of evidence was found regarding its effect on quality of life. To the other complementary therapies it was not possible to synthetize evidence level.ConclusionTai chi may be used as an important resource to improve functional capacity and quality of life among prefrail and frail older adults.  相似文献   
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In this article, I examine the changing representation of medical error in high circulating North American popular magazines in three time periods 1980–1989, 1990–1999 and 2000–2014. Although there were stories of medical error in all the time periods they differed both in their frequency and in the dominant discourses. In the first decade, medical error was represented as an occasional, unique and unusual event. In the next two and a half decades and progressively over time, medical error was represented as commonplace in all parts of the health care system, at all stages of life and from pre-diagnosis to death. Readers are increasingly expected to take responsibility for managing the risk of such errors by continuous, assiduous monitoring of the possible dangers of mistakes made by doctors, in hospitals, in laboratories, that is everywhere in the medical care system. This changing representation of medical error can be linked to the changes in the health care associated with the medicalisation of everyday life, the implementation of neo-liberal ideology and the expansion of the risk society. The individualisation of citizens as isolated, separate units is a bedrock value and assumption of all three of these major discourses. Medicalisation is based on the assumption that health problems develop in the individual body and the individual should follow medical advice to prevent them and should seek medical treatment if such prevention fails. Neo-liberalism devalues the role of the state in ensuring social welfare, emphasising the importance of individual initiative and self-responsibility for health and well-being. In the risk society, the individual is responsible for identifying and managing the risks of everyday life.  相似文献   
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The Hayling task is traditionally used to assess activation and inhibitory processes efficiency among various populations, such as elderly adults. However, the classical design of the task may also involve the influence of strategy use and efficiency of sentence processing in the possible differences between individuals. Therefore, the present study investigated activation and inhibitory processes in aging with two formats of an adapted Hayling task designed to reduce the involvement of these alternative factors. Thirty young adults (M = 20.7 years) and 31 older adults (M = 69.6 years) performed an adapted Hayling task including a switching block (i.e., unblocked design) in addition to the classical task (i.e., blocked design), and the selection of the response between two propositions. The results obtained with the classical blocked design showed age-related deficits in the suppression sections of the task but also in the initiation ones. These findings can be explained by a co-impairment of both inhibition and activation processes in aging. The results of the unblocked Hayling task, in which strategy use would be reduced, confirmed this age-related decline in both activation and inhibition processes. Moreover, significant correlations between the unblocked design and the Trail Making Test revealed that flexibility is equally involved in the completion of both sections of this design. Finally, the use of a forced-response choice offers a format that is easy to administer to people with normal or pathological aging. This seems particularly relevant for these populations in whom the production of an unrelated word often poses problems.  相似文献   
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To test the validity of published equations, 79 Caucasian adults (40 men and 39 women) aged 50–78 y had muscle thickness (MT) measured by ultrasound at nine sites of the body. Fat-free mass (FFM), lean soft tissue mass (LM) and total muscle mass (TMM) were estimated from MT using equations previously published in the literature. Appendicular LM (aLM) was estimated using dual-energy X-ray absorptiometry (DXA) and this method served as the reference criterion. There were strong correlations (range r = 0.85–0.94) between DXA-derived aLM and estimated FFM, leg LM or TMM. Total error between DXA-derived aLM and TMM (∼2 kg) was lower compared with the three other selected equations (6–10 kg). A Bland-Altman plot revealed that there was no systematic bias between aLM and TMM; however, the other three equations included systematic error. Our results suggest that an ultrasound equation for TMM is appropriate and useful for evaluating skeletal muscle mass in the body.  相似文献   
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Strong consensus exists regarding the most robust environmental intervention for attenuating aging processes and increasing healthspan and lifespan: calorie restriction (CR). Over several decades, this paradigm has been replicated in numerous nonhuman models, and has been expanded over the last decade to formal, controlled human studies of CR. Given that long-term CR can create heavy challenges to compliance in human diets, the concept of a calorie restriction mimetic (CRM) has emerged as an active research area within gerontology. In past presentations on this subject, we have proposed that a CRM is a compound that mimics metabolic, hormonal, and physiological effects of CR, activates stress response pathways observed in CR and enhances stress protection, produces CR-like effects on longevity, reduces age-related disease, and maintains more youthful function, all without significantly reducing food intake, at least initially. Over 16 years ago, we proposed that glycolytic inhibition could be an effective strategy for developing CRM. The main argument here is that inhibiting energy utilization as far upstream as possible provides the highest chance of generating a broad spectrum of CR-like effects when compared to targeting a singular molecular target downstream. As an initial candidate CRM, 2-deoxyglucose, a known anti-glycolytic, was shown to produce a remarkable phenotype of CR, but further investigation found that this compound produced cardiotoxicity in rats at the doses we had been using. There remains interest in 2DG as a CRM but at lower doses. Beyond the proposal of 2DG as a candidate CRM, the field has grown steadily with many investigators proposing other strategies, including novel anti-glycolytics. Within the realm of upstream targeting at the level of the digestive system, research has included bariatric surgery, inhibitors of fat digestion/absorption, and inhibitors of carbohydrate digestion. Research focused on downstream sites has included insulin receptors, IGF-1 receptors, sirtuin activators, inhibitors of mTOR, and polyamines. In the current review we discuss progress made involving these various strategies and comment on the status and future for each within this exciting research field.  相似文献   
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IntroductionThe choroid plexuses, blood vessels, and brain barriers are closely related both in terms of morphology and function. Hypertension causes changes in cerebral blood flow and in small vessels and capillaries of the brain. This review studies the effects of high blood pressure (HBP) on the choroid plexuses and brain barriers.DevelopmentThe choroid plexuses (ChP) are structures located in the cerebral ventricles, and are highly conserved both phylogenetically and ontogenetically. The ChPs develop during embryogenesis, forming a functional barrier during the first weeks of gestation. They are composed of highly vascularised epithelial tissue covered by microvilli, and their main function is cerebrospinal fluid (CSF) production. The central nervous system (CNS) is protected by the blood-brain barrier (BBB) and the blood–CSF barrier (BCSFB). While the BBB is formed by endothelial cells of the microvasculature of the CNS, the BCSFB is formed by epithelial cells of the choroid plexuses. Chronic hypertension induces vascular remodelling. This prevents hyperperfusion at HBPs, but increases the risk of ischaemia at low blood pressures. In normotensive individuals, in contrast, cerebral circulation is self-regulated, blood flow remains constant, and the integrity of the BBB is preserved.ConclusionsHBP induces changes in the choroid plexuses that affect the stroma, blood vessels, and CSF production. HBP also exacerbates age-related ChP dysfunction and causes alterations in the brain barriers, which are more marked in the BCSFB than in the BBB. Brain barrier damage may be determined by quantifying blood S-100β and TTRm levels.  相似文献   
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