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   202534篇
  免费   12469篇
  国内免费   6022篇
耳鼻咽喉   998篇
儿科学   3363篇
妇产科学   2221篇
基础医学   27364篇
口腔科学   5835篇
临床医学   16058篇
内科学   41443篇
皮肤病学   3225篇
神经病学   15987篇
特种医学   4516篇
外国民族医学   20篇
外科学   21648篇
综合类   22822篇
一般理论   5篇
预防医学   13422篇
眼科学   3343篇
药学   22442篇
  34篇
中国医学   6778篇
肿瘤学   9501篇
  2023年   2396篇
  2022年   3526篇
  2021年   6682篇
  2020年   5805篇
  2019年   9701篇
  2018年   9634篇
  2017年   7755篇
  2016年   5211篇
  2015年   5819篇
  2014年   10414篇
  2013年   11606篇
  2012年   9759篇
  2011年   11046篇
  2010年   8800篇
  2009年   8222篇
  2008年   8477篇
  2007年   8413篇
  2006年   7347篇
  2005年   6670篇
  2004年   5573篇
  2003年   4979篇
  2002年   3887篇
  2001年   3490篇
  2000年   2940篇
  1999年   2565篇
  1998年   2041篇
  1997年   1921篇
  1996年   1587篇
  1995年   1588篇
  1994年   1440篇
  1993年   1185篇
  1992年   1065篇
  1991年   926篇
  1990年   769篇
  1989年   668篇
  1988年   608篇
  1987年   556篇
  1985年   3677篇
  1984年   4206篇
  1983年   3432篇
  1982年   3877篇
  1981年   3489篇
  1980年   2906篇
  1979年   2793篇
  1978年   2313篇
  1977年   1752篇
  1976年   2203篇
  1975年   1690篇
  1974年   1468篇
  1973年   1383篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
1.
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.  相似文献   
2.
3.
The discussion paper will focus on continuity of care relating to previous NZ research, specifically to transitioning complex preterm infants from NICU to home based on parent experiences, and on the practice developments that have occurred, to ensure optimal health outcomes. Previous NZ research discovered parent desire a consistent service delivery for the entire transition journey from NICU and at home.An informative and comprehensive opportunity has occurred for reflective professional practice, evaluation, development and implementation which have transpired in positive change through innovative practice developments and support change implementation in Wellington, NZ. This has resulted in the articulation of a model of care that has both embraced and integrated parental desires for a continuity of care process for complex preterm infants. This has been achieved by having the same Discharge Facilitator/Key Case Manager present within the NICU and external to the NICU for Home-based infants for the entire transition journey.The paper will focus and emphasis additional practice development changes and furthermore, will present a real purpose, for other countries to learn of such practice developments that have exemplified a celebratory success for families of Wellington, NZ.  相似文献   
4.
田玥  邹健 《现代肿瘤医学》2022,(23):4377-4382
胃癌作为临床最常见的肿瘤之一,常因确诊疾病较晚而影响治疗效果,胃镜活检后的病理虽然作为确诊的金标准,但是由于此方式过程痛苦,操作复杂,费用较高,且具有侵入性,可能会导致患者拒绝操作而难普及于临床,因此积极找寻胃癌有效的监测指标十分必要。近年来,很多学者研究维生素与胃癌的相关关系,并试图通过摄取某些维生素降低胃癌发生率,延缓病情及改善预后,也有通过检测血清中维生素的水平给早期胃癌的诊断提供帮助。本文就同型半胱氨酸、维生素D、维生素C、维生素E、维生素B12及叶酸在胃癌中的作用机制,及其在血清中水平与胃癌关系的相关研究进展进行简要综述,为临床胃癌诊疗提供新思路。  相似文献   
5.
Numerous risk variables, including age, medical co-morbidities, and deranged inflammatory response, lead to higher mortality in a senior population with coronavirus disease 2019. C-reactive protein (CRP), an acute phase inflammatory protein secreted by the liver, was tested in the elderly, showing a diagnostic and prognostic role. However, recent research has shed light on new applications for CRP in geriatrics. It was used as a follow-up marker and as a therapeutic target. Early and accurate identification of patients' risks may mitigate the devastation of the invading virus in older cases and permit the implementation of a quick treatment plan for those most likely to deteriorate.  相似文献   
6.
ObjectiveTo evaluate the long-term incidence and outcome of aortic interventions for medically managed uncomplicated thoracic aortic dissections.MethodsBetween January 2012 and December 2018, 91 patients were discharged home with an uncomplicated, medically treated aortic dissection (involving the descending aorta with or without aortic arch involvement, no ascending involvement). After a median period of 4 (first quartile: 2, third quartile: 11) months, 30 patients (33%) required an aortic intervention. Patient characteristics, radiographic, treatment, and follow-up data were compared for patients with and without aortic interventions. A competing risk regression model was analyzed to identify independent predictors of aortic intervention and to predict the risk for intervention.ResultsPatients who underwent aortic interventions had significantly larger thoracic (P = .041) and abdominal (P = .015) aortic diameters, the dissection was significantly longer (P = .035), there were more communications between both lumina (P = .040), and the first communication was significantly closer to the left subclavian artery (P = .049). A descending thoracic aortic diameter exceeding 45 mm was predictive for an aortic intervention (P = .001; subdistribution hazard ratio: 3.51). The risk for aortic intervention was 27% ± 10% and 36% ± 11% after 1 and 3 years, respectively. Fourteen patients (47%) underwent thoracic endovascular aortic repair, 11 patients (37%) thoracic endovascular aortic repair and left carotid to subclavian bypass, 3 patients (10%) total arch replacement with the frozen elephant trunk technique, and 2 patients (7%) thoracoabdominal aortic replacement. We observed no in-hospital mortality.ConclusionsThe need for secondary aortic interventions in patients with initially medically managed, uncomplicated descending aortic dissections is substantial. The full spectrum of aortic treatment options (endovascular, hybrid, conventional open surgical) is required in these patients.  相似文献   
7.
BackgroundAdverse drug reactions (ADRs) and adverse drug events (ADEs) in older people contribute to a significant proportion of hospital admissions and are common following discharge. Effective interventions are therefore required to combat the growing burden of preventable ADRs. The Prediction of Hospitalisation due to Adverse Drug Reactions in Elderly Community Dwelling Patients (PADR-EC) score is a validated risk score developed to assess the risk of ADRs in people aged 65 years and older and has the potential to be utilised as part of an intervention to reduce ADRs.ObjectivesThis trial was designed to investigate the effectiveness of an intervention to reduce ADR incidence in older people and to obtain further information about ADRs and ADEs in the 12–24 months following hospital discharge.MethodsThe study is an open-label randomised-controlled trial to be conducted at the Royal Hobart Hospital, a 500-bed public hospital in Tasmania, Australia. Community-dwelling patients aged 65 years and older with an unplanned overnight admission to a general medical ward will be recruited. Following admission, the PADR-EC ADR score will be calculated by a research pharmacist, with the risk communicated to clinicians and discussed with participants. Following discharge, nominated general practitioners and community pharmacists will receive the risk score and related medication management advice to guide their ongoing care of the patient. Follow-up with participants will occur at 3 and 12 and 18 and 24 months to identify ADRs and ADEs. The primary outcome is moderate-severe ADRs at 12 months post-discharge, and will be analysed using the cumulative incidence proportion, survival analysis and Poisson regression.SummaryIt is hypothesised that the trial will reduce ADRs and ADEs in the intervention population. The study will also provide valuable data on post-discharge ADRs and ADEs up to 24 months post-discharge.  相似文献   
8.
Transition to practice experiences for new primary care nurse practitioners (NPs) is of interest, particularly considering the lack of requirements and options for formal training programs. The purpose of this article is to describe new primary care NPs’ experience and perceived needs of transitioning to practice. New Nebraska NPs were surveyed. The main findings include increased confidence and perceived preparedness after 3 months of practice, as well as challenges and helpful supportive services for transitioning to practice. Additional information on the transition to practice experience was provided and supports developing a formal program.  相似文献   
9.
《Vaccine》2022,40(27):3721-3726
We initiated a randomized, placebo-controlled, phase 1/2 trial to evaluate the safety and immunogenicity of the S-268019-b recombinant protein vaccine, scheduled as 2 intramuscular injections given 21 days apart, in 60 randomized healthy Japanese adults. We evaluated 2 regimens of the S-910823 antigen (5 μg [n = 24] and 10 μg [n = 24]) with an oil-in-water emulsion formulation and compared against placebo (n = 12). Reactogenicity was mild in most participants. No serious adverse events were noted. For both regimens, vaccination resulted in robust IgG and neutralizing antibody production at days 36 and 50 and predominant T-helper 1-mediated immune reaction, as evident through antigen-specific polyfunctional CD4+ T-cell responses with IFN-γ, IL-2, and IL-4 production on spike protein peptides stimulation. Based on the interim analysis, the S-268019-b vaccine is safe, produces neutralizing antibodies titer comparable with that in convalescent serum from COVID-19-recovered patients. However, further evaluation of the vaccine in a large clinical trial is warranted.  相似文献   
10.
目的探讨乙肝相关性肝癌临床病理学特征与溶血磷脂酸(LPA)和高敏C反应蛋白(hs-CRP)表达的相关性。方法选取2019年1月至2020年1月间河南省驻马店市中心医院收治的198例乙肝相关性肝癌患者作为乙肝组,198例酒精相关性肝癌患者作为酒精组。两组患者都进行血清hs-CRP和LPA表达检测,调查患者的病理学特征并进行相关性分析。结果乙肝组患者血清hs-CRP和LPA含量均高于酒精组,差异均有统计学意义(均P <0.05)。两组患者血清ALP、AFP、ALT、AST和GGT含量比较,差异均无统计学意义(P> 0.05)。乙肝组不同临床分期和组织学分化患者的血清hs-CRP和LPA含量比较,差异均有统计学意义(均P <0.05)。乙肝组患者的临床分期和组织学分化与血清hs-CRP和LPA表达均存在相关性,差异均有统计学意义(均P <0.05)。患者的临床分期和组织学分化均为影响hs-CRP和LPA表达的重要因素,差异均有统计学意义(均P <0.05)。结论相对于酒精相关性肝癌,乙肝相关性肝癌的血清hs-CRP和LPA呈现高表达,与患者的临床病理学特征存在相关性。  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