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   77004篇
  免费   5611篇
  国内免费   2131篇
耳鼻咽喉   487篇
儿科学   1430篇
妇产科学   2327篇
基础医学   7085篇
口腔科学   1283篇
临床医学   8081篇
内科学   7090篇
皮肤病学   919篇
神经病学   4450篇
特种医学   1763篇
外国民族医学   7篇
外科学   5024篇
综合类   12995篇
现状与发展   4篇
一般理论   8篇
预防医学   13694篇
眼科学   1731篇
药学   8398篇
  109篇
中国医学   5026篇
肿瘤学   2835篇
  2024年   120篇
  2023年   1047篇
  2022年   1486篇
  2021年   2719篇
  2020年   2808篇
  2019年   2435篇
  2018年   2316篇
  2017年   2381篇
  2016年   2415篇
  2015年   2368篇
  2014年   5146篇
  2013年   5919篇
  2012年   5125篇
  2011年   5383篇
  2010年   4293篇
  2009年   3758篇
  2008年   3807篇
  2007年   3640篇
  2006年   3201篇
  2005年   2777篇
  2004年   2362篇
  2003年   2323篇
  2002年   1651篇
  2001年   1592篇
  2000年   1261篇
  1999年   1160篇
  1998年   990篇
  1997年   981篇
  1996年   898篇
  1995年   845篇
  1994年   707篇
  1993年   593篇
  1992年   543篇
  1991年   508篇
  1990年   512篇
  1989年   423篇
  1988年   308篇
  1987年   276篇
  1986年   330篇
  1985年   455篇
  1984年   435篇
  1983年   264篇
  1982年   340篇
  1981年   273篇
  1980年   301篇
  1979年   221篇
  1978年   179篇
  1977年   167篇
  1976年   160篇
  1975年   113篇
排序方式: 共有10000条查询结果,搜索用时 734 毫秒
71.
Due to the optimal results obtained in kidney transplantation and to the lack of interest of the industries, new innovative drugs in kidney transplantation are difficult to be encountered. The best strategy to find the new drugs recently developed or under development is to search in the sections of kidney transplantation still not completely covered by the drugs on the market. These unmet needs are the prevention of delayed graft function (DGF), the protection of the graft over the long time and the desensitization of preformed anti human leukocyte antigen antibodies and the treatment of the acute antibody-mediated rejection. These needs are particularly relevant due to the expansion of some kind of kidney transplantation as transplantation from non-heart beating donor and in the case of antibody-incompatible grafts. The first are particularly exposed to DGF, the latter need a safe desensitization and a safe treatments of the antibody mediated rejections that often occur. Particular caution is needed in treating these drugs. First, they are described in very recent studies and the follow-up of their effect is of course rather short. Second, some of these drugs are still in an early phase of study, even if in well-conducted randomized controlled trials. Particular caution and a careful check need to be used in trials launched 2 or 3 years ago. Indeed, is always necessary to verify whether the study is still going on or whether and why the study itself was abandoned.  相似文献   
72.
73.
《L'Encéphale》2022,48(2):179-187
Recent contradictory data has renewed discussion regarding the existence of adult hippocampal neurogenesis (AHN) in humans, i.e., the continued production of new neurons in the brain after birth. The present review revisits the debate of AHN in humans from a historical point of view in the face of contradictory evidence, analyzing the methods employed to investigate this phenomenon. Thus, to date, of the 57 studies performed in humans that we reviewed, 84% (48) concluded in favor of the presence of newborn neurons in the human adult hippocampus. Besides quality of the tissue (such as postmortem intervals below 26 hours as well as tissue conservation and fixation), considerations for assessing and quantify AHN in the human brain require the use of stereology and toxicological analyses of clinical data of the patient.  相似文献   
74.
Background and aimPatient decision aids for oncological treatment options, provide information on the effect on recurrence rates and/or survival benefit, and on side-effects and/or burden of different treatment options. However, often uncertainty exists around the probability estimates for recurrence/survival and side-effects which is too relevant to be ignored. Evidence is lacking on the best way to communicate these uncertainties. The aim of this study is to develop a method to incorporate uncertainties in a patient decision aid for breast cancer patients to support their decision on radiotherapy.MethodsFirstly, qualitative interviews were held with patients and health care professionals. Secondly, in the development phase, thinking aloud sessions were organized with four patients and 12 health care professionals, individual and group-wise.ResultsConsensus was reached on a pictograph illustrating the whole range of uncertainty for local recurrence risks, in combination with textual explanation that a more exact personalized risk would be given by their own physician. The pictograph consisted of 100 female icons in a 10 x 10 array. Icons with a stepwise gradient color indicated the uncertainty margin. The prevalence and severity of possible side-effects were explained using verbal labels.ConclusionsWe developed a novel way of visualizing uncertainties in recurrence rates in a patient decision aid. The effect of this way of communicating risk uncertainty is currently being tested in the BRASA study (NCT03375801).  相似文献   
75.
Objectives: The present study aims to evaluate the role of Positron emission tomography (PET) -computed tomography (CT) with 18F-fluorodeoxyglucose (18F-FDG) in the restaging of high-risk testicular cancer. Methods: Forty-five patients (mean age of 38.1±11.3 years and range 23-81 years) with testicular carcinoma, underwent 18F-FDG PET-CT during their clinical course were prospectively selected. PET positivity was defined as a site of abnormal 18F-FDG uptake in tissue histologically proven or clinically or radiographically suspected to represent tissue involvement. The sites of disease were characterized as either nodal or extranodal. All patients were followed-up for at least 12 months with a diagnostic and/or functional imaging modality. Results: Of the 45 patients 38 (84%) patient presented with seminoma and 7 (16%) were Non-seminomatous germ cell tumors. Analysis of secondary disease spectrum showed nodal involvement in 65%, osseous involvement in 23% and mixed visceral/soft tissue lesions in 12% of patients. Nineteen (42%) were negative for any metastatic disease. All negative patients remain disease free in the follow-up of one year. Out of the positive 26/45 patients, PET-CT showed progressive disease in 3/26, stable disease 1/26 and partial response in 2/26 and complete metabolic resolution in 20/26 patients. 18F-FDG PET-CT was able to characterize all patients leading to significant change of primary decision of wait and watch to go for treatment and vice versa. Conclusion: 18F-FDG PET-CT scan is potentially an excellent tool for characterization of equivocal lesions on CT scan in the restaging settings and follow up of high-risk testicular cancer patients.  相似文献   
76.
目的:分析和研究黄芪桂枝汤对于风湿痹证患者的改善作用。方法:选择了56例患者进行研究主要对象,将所有参与研究的56例患者分成了对照组(28例)和观察组(28例),使用的分组方式为随机数字表法。对照组使用的治疗方式为西药,观察组则在西药治疗的基础之上增加了黄芪桂枝汤进行联合治疗。之后对比两个组别患者的治疗疗效以及疼痛积分值。结果:对照组之中有11例患者为治愈,11例患者为好转,剩余6例患者为未愈;观察组之中有15例患者为治愈,12例患者为好转,剩余1例患者为未愈,对照组之中患者的治疗疗效明显低于观察组之中的患者。在进行治疗之前,对照组与观察组患者之间的对比不具有统计学意义,对照组当中患者的疼痛积分值明显低于观察组患者,P <0.05说明数据的差异存在统计学意义。结论:在对风湿痹证患者进行治疗时,加用黄芪桂枝汤能够起到标本兼治以及扶正祛邪的作用,值得推广。  相似文献   
77.
目的 探讨营养风险与腹膜后肿瘤患者住院时间的相关性。方法 采用回顾性研究,选取2012年1月至2018年12月四川大学华西医院血管外科新入院腹膜后肿瘤患者60例,采用营养风险筛查表评估患者营养风险,收集患者体质指数、围术期血红蛋白和白蛋白水平、住院天数、术后恶心呕吐发生情况、术后排气、排便时间和首次进食时间。采用单因素分析比较不同患者住院时间,采用多重线性逐步回归分析患者住院时间的影响因素。结果 纳入的60例腹膜后肿瘤患者中,40例患者(66.7%)术前存在营养风险,52例患者(86.7%)术后存在营养风险;单因素分析显示,患者术前、术后营养风险 (术前P<0.001,术后P=0.043)、术前白蛋白 (P=0.019)、术后血红蛋白 (P=0.019)、术后白蛋白(P=0.025) 水平以及术后恶心呕吐 (P=0.001) 均会影响患者的住院时间;患者住院时间与围术期营养风险筛查工具评分、术后首次进食时间、术后排气时间和排便时间具有相关性,且相关性强(r=0.759~0.770; P<0.01);多因素分析显示术前营养风险是腹膜后肿瘤患者住院时间的重要预测因素(β=0.399)。结论 术前营养风险是腹膜后肿瘤患者住院时间的预测因子。  相似文献   
78.
《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology.  相似文献   
79.
ABSTRACT

Take-Away Points:

1. Geriatric palliative care requires integrating the disciplines of hospital medicine and palliative care in pursuit of delivering comprehensive, whole-person care to aging patients with serious illnesses.

2. Older adults have unique palliative care needs compared to the general population, different prevalence and intensity of symptoms, more frequent neuropsychiatric challenges, increased social needs, distinct spiritual, religious, and cultural considerations, and complex medicolegal and ethical issues.

3. Hospital-based palliative care interdisciplinary teams can take many forms and provide high-quality, goal-concordant care to older adults and their families.  相似文献   
80.
目的 系统评价有关癌症患者心理韧性发展的真实体验,为更好地制定心理韧性干预方案提供理论依据。方法 计算机检索Cochrane Library、Medline、CINAHL、Embase、PubMed、Web of Science、Psyc INFO以及中国生物医学文献数据库、中国知网、维普、万方数据库从建库至2019年6月相关的质性研究。采用澳大利亚乔安娜布里格斯研究所循证卫生保健中心质性研究质量评价标准(2016)对文献进行评价,采用汇集性整合方法进行结果整合。结果 共纳入10篇文献,提炼42个明确的结果,形成8个类别,汇总成3个整合结果。①心理韧性发展是动态循环的过程:危机负性期,调节成长期,积极转化期,循环强化期;②心理韧性的阻碍因素:个体(消极应对,错误认知,症状和体象困扰),环境(传统社会文化,医疗环境,家庭负担);③心理韧性的保护因素:个体(积极心理与应对方式,复原经历,宗教信仰,自我表露,利他主义与行为),环境(家庭因素,医疗照护,人际支持)。结论 心理韧性的发展是动态循环过程,受个体和环境因素影响,医护人员应根据不同阶段的影响因素给予针对性护理措施,促进患者心理韧性的形成和发展,提高患者的生活质量。  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