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31.
《Journal of the American Medical Directors Association》2020,21(5):621-626.e2
ObjectivesQuantifying the association between muscle weakness and mortality with carefully matched cohorts will help to better establish the impact of weakness on premature death. We used a matched cohort analysis in a national sample of older Americans to determine if those who were weak had a higher risk for mortality compared with control groups with incrementally higher strength capacities.DesignLongitudinal panel.SettingDetailed interviews that included physical measures were conducted in person, whereas core interviews were often performed over the telephone.ParticipantsData from 19,729 Americans aged at least 50 years from the 2006-2014 waves of the Health and Retirement Study were analyzed.MeasuresA handgrip dynamometer was used to assess handgrip strength (HGS) in each participant. Men with HGS <26 kg were considered weak, ≥26 kg were considered not weak, and ≥32 kg were considered strong. Women with HGS <16 kg were classified as weak, ≥16 kg were classified as not-weak, and ≥20 kg were classified as strong. The National Death Index and postmortem interviews determined the date of death. The greedy matching algorithm was used to match cohorts.ResultsOf the 1077 weak and not-weak matched pairs, 401 weak (37.2%) and 296 not-weak (27.4%) older Americans died over an average 4.4 ± 2.5-year follow-up. There were 392 weak (37.0%) and 243 strong (22.9%) persons who died over a mean 4.5 ± 2.5-year follow-up from the 1057 weak and strong matched pairs. Those in the weak cohort had a 1.40 [95% confidence interval (CI) 1.19, 1.64] and 1.54 (CI 1.30, 1.83) higher hazard for mortality relative to persons in the not-weak and strong control cohorts, respectively.Conclusions and ImplicationsOur findings may indicate a causal association between muscle weakness and mortality in older Americans. Health care providers should include measures of HGS as part of routine health assessments and discuss the health risks of muscle weakness with their patients. 相似文献
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The aging process results in multiple traceable footprints, which can be quantified and used to estimate an organism's age. Examples of such aging biomarkers include epigenetic changes, telomere attrition, and alterations in gene expression and metabolite concentrations. More than a dozen aging clocks use molecular features to predict an organism's age, each of them utilizing different data types and training procedures. Here, we offer a detailed comparison of existing mouse and human aging clocks, discuss their technological limitations and the underlying machine learning algorithms. We also discuss promising future directions of research in biohorology — the science of measuring the passage of time in living systems. Overall, we expect deep learning, deep neural networks and generative approaches to be the next power tools in this timely and actively developing field. 相似文献
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Krishna S. Iyer 《Platelets》2020,31(4):474-482
Abstract Platelets are small, anucleated effector cells that play an important role in linking the hemostatic and inflammatory processes in the body. Platelet function is known to be altered under various inflammatory conditions including aging. A gain in platelet function during aging can increase the risk of thrombotic events, such as stroke and acute myocardial infarction. Anti-platelet therapy is designed to reduce risk of serious cerebrovascular and cardiovascular events, but the adverse consequences of therapy, such as risk for bleeding increases with aging as well. Age-associated comorbidities such as obesity, diabetes, and hyperlipidemia also contribute to increased platelet activity and thus can enhance the risk of thrombosis. Therefore, identification of unique mechanisms of platelet dysfunction in aging and in age-associated comorbidities is warranted to design novel antiplatelet drugs. This review outlines some of the current areas of research on aging-related mechanisms of platelet hyperactivity and addresses the clinical urgency for designing anti-platelet therapies toward novel molecular targets in the aging population. 相似文献
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《Anais brasileiros de dermatologia》2020,95(1):91-94
This ecological study aims to analyze both the tendency and the characteristics of leprosy in the elderly population in the state of Bahia, 2001–2017. The tendency was analyzed through joinpoint regression. Epidemiological variables were also included in the study. The average detection rate was 38.73/100,000, with prevalence of men (45.19/100,000). A downward trend occurred in both genders, from 2004, with a greater magnitude in women (annual percent change [APC] = −3.4%). Men presented higher proportions of the multibacillary forms and physical disabilities. The epidemiological scenario indicates the need of implementation of actions that stimulate early diagnosis and treatment of the elderly population. 相似文献
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目的 本研究旨在探讨吸毒人员回归社会后的自我概念及应对方式是否会影响其生活质量。方法 在四川省成都市、德阳市、西昌市、宜宾市等地招募201名已回归社会的男性吸毒人员(平均年龄22.65±8.31岁,年龄16~59岁)进行调查。参与者完成田纳西自我概念量表(TSCS)、特质应对方式问卷(TCSQ)和药物成瘾者生命质量测定量表(QOL-DA)。结果 高自我概念组吸毒人员的积极应对得分和生活质量均高于低自我概念组,差异具有统计学意义(P<0.05);吸毒人员的自我概念在积极应对与生活质量之间的中介效应值为0.224(95%CI:0.063~0.434),中介效应显著,占总效应的26.4%。结论 自我概念介导了回归社会的吸毒人员应对方式与生活质量之间的关系,应在学校和特定社区开展提高自我概念和应对技巧的培训。 相似文献
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AimsNear-infrared spectroscopy (NIRS) is a non-invasive, easy to apply, optical technology for measuring cerebral blood oxygenation, but there is lack of comprehensive population data to aid interpretation and clinical use. Given the importance of cerebral perfusion in the context of evolving guideline recommendations for more aggressive lowering of blood pressure (BP) in hypertension, even in the oldest old, understanding of normative NIRS values is timely. We estimated normative values of cerebral oxygenation measured by NIRS in a large community-dwelling population sample of adults aged > = 50 years (n = 3110). We hypothesized that measurements would be attenuated by cardiovascular risk factors.MethodsData from Wave 3 of The Irish Longitudinal Study on Ageing (TILDA) was utilized. Frontal lobe cerebral oxygenation was continuously measured via a Portalite, while participants rested in the supine position. Beat-to-beat BP was measured simultaneously. Normative data was modelled using generalized additive models for location, scale, and shape (GAMLSS). Multivariate linear regressions were used to examine associations with cardiovascular risk factors.ResultsAll three measures of NIRS (TSI, O2Hb and HHb) declined with increasing age. O2Hb and HHb were significantly lower in males than females. Increased smoking, excess alcohol intake, a higher waist-hip ratio, diabetes, angina, congestive heart failure, transient ischemic attack and total cardiovascular disease burden were all associated with decreased cerebral oxygenation.ConclusionWe present for the first time, normative resting-state NIRS reference data from a large population, which contributes to clinical interpretation of NIRS and advances the use of NIRS as a standard clinical tool. 相似文献