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   132051篇
  免费   9615篇
  国内免费   4175篇
耳鼻咽喉   763篇
儿科学   3137篇
妇产科学   2848篇
基础医学   14603篇
口腔科学   1419篇
临床医学   13153篇
内科学   12887篇
皮肤病学   1008篇
神经病学   19026篇
特种医学   5247篇
外国民族医学   12篇
外科学   9927篇
综合类   20859篇
现状与发展   4篇
一般理论   6篇
预防医学   9566篇
眼科学   1891篇
药学   13672篇
  95篇
中国医学   10328篇
肿瘤学   5390篇
  2024年   315篇
  2023年   1755篇
  2022年   3101篇
  2021年   4838篇
  2020年   4445篇
  2019年   3970篇
  2018年   3829篇
  2017年   4062篇
  2016年   4188篇
  2015年   4172篇
  2014年   7884篇
  2013年   9322篇
  2012年   7594篇
  2011年   8178篇
  2010年   6701篇
  2009年   6041篇
  2008年   6114篇
  2007年   6211篇
  2006年   5809篇
  2005年   5027篇
  2004年   4138篇
  2003年   3985篇
  2002年   3189篇
  2001年   2928篇
  2000年   2488篇
  1999年   2268篇
  1998年   1956篇
  1997年   2035篇
  1996年   1735篇
  1995年   1634篇
  1994年   1494篇
  1993年   1221篇
  1992年   1160篇
  1991年   998篇
  1990年   967篇
  1989年   845篇
  1988年   775篇
  1987年   683篇
  1986年   754篇
  1985年   954篇
  1984年   981篇
  1983年   614篇
  1982年   786篇
  1981年   658篇
  1980年   647篇
  1979年   441篇
  1978年   356篇
  1977年   324篇
  1976年   281篇
  1975年   201篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
2.
3.
4.
《Cirugía espa?ola》2022,100(3):149-153
IntroductionThe Law for the Regulation of Health Professions (LOPS) indicates that health professionals will carry out continuous training throughout their professional life, and will regularly prove their professional competence. The objective of the study was to carry out a national survey to find out the opinion of Spanish surgeons and thus be able to prepare a recertification project by the Spanish Association of Surgeons (AEC).MethodsCross-sectional observational study carried out in June-July 2020, through a survey sent to the members of the AEC.ResultsThe survey had a total of 1230 visits and an overall completion rate of 784 responses (67.3%). 69.6% were unaware of the LOPS forecasts and 83.4% were unaware of similar initiatives in other specialties and 95.5% agreed to demand adequate information. 71.4% believed it necessary but only 57% believed that it should be mandatory. 82.9% would agree that it should be regulated through an objective and predictable official procedure.ConclusionsThe concept of re-accreditation is not well known in our specialty and in view of the results obtained, adequate and reliable information seems necessary. Therefore, it would be pertinent to propose by the AEC a specific project to assess activities and skills.  相似文献   
5.
《Clinical neurophysiology》2021,132(10):2357-2364
ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents.MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed.ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts.ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential.SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities.  相似文献   
6.
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19.  相似文献   
7.
8.

Background

Hyperglycaemia is common in patients with acute brain injury admitted to an intensive care unit (ICU). Many studies have found associations between development of hyperglycaemia and increased mortality in hospitalised patients. However, the optimal target for blood glucose control is unknown. We want to conduct a systematic review with meta-analysis and trial sequential analysis to explore the beneficial and harmful effects of restrictive versus liberal glucose control on patient outcomes in adults with severe acute brain injury.

Methods

We will systematically search medical databases including CENTRAL, Embase, MEDLINE and trial registries. We will search the following websites for ongoing or unpublished trials: http://www.controlled-trials.com/ , http://www.clinicaltrials.gov/ , www.eudraCT.com , http://centerwatch.com/ , The Cochrane Library's CENTRAL, PubMed, EMBASE, Science Citation Index Expanded and CINAHL. Two authors will independently review and select trials and extract data. We will include randomised trials comparing levels of glucose control in our analyses and observational studies will be included to address potential harms. The primary outcomes are defined as all-cause mortality, functional outcome and health-related quality of life. Secondary outcomes include serious adverse events including hypoglycaemia, length of ICU stay and duration of mechanical ventilation, and explorative outcomes including intracranial pressure and infection. Trial Sequential Analysis will be used to investigate the risk of type I error due to repetitive testing and to further explore imprecision. Quality of trials will be evaluated using the Cochrane Risk of Bias tool, and quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

Discussion

The results of the systematic review will be disseminated through peer-reviewed publication. With the review, we hope to inform future randomised clinical trials and improve clinical practice.  相似文献   
9.
目的:了解流动人口基层首诊现状及其影响因素,为推进流动人口分级诊疗提供实证参考依据。方法:基于2017年全国流动人口动态监测调查数据中82734名最近1次患病(负伤)流动人口数据,利用SPSS 25.0统计软件分析其基层首诊情况及影响因素。结果:82734名最近1次患病(负伤)流动人口中首选到基层医疗卫生机构就诊15936人,基层首诊率仅为19.3%;二分类logistic回归分析结果显示:年龄≥65岁、农业户口、流动时间0~5年、患慢性病、至少参加1项医疗保险,居住地到最近医疗服务机构所需时间≤15 min的流动人口患病后更愿意选择到基层首诊。学历大专及以上、家庭月均收入>10000元、市跨县、东北地区、不愿意落户、自评健康状况为不健康的流动人口患病后更不愿意选择到基层首诊。结论:流动人口患病(负伤)后选择到基层首诊率较低,年龄、受教育程度、户口类型、家庭月均总收入、流动时间、流动范围、流入地区域、落户意愿、自评健康状况、是否患慢性病、有无参加医疗保险、居住地到最近医疗服务机构所需时间是影响流动人口患病(负伤)后选择到基层首诊的主要因素。  相似文献   
10.
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