首页 | 官方网站   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   38955篇
  免费   1657篇
  国内免费   788篇
医药卫生   41400篇
  2023年   314篇
  2022年   586篇
  2021年   937篇
  2020年   865篇
  2019年   730篇
  2018年   795篇
  2017年   922篇
  2016年   1032篇
  2015年   921篇
  2014年   1932篇
  2013年   2477篇
  2012年   1944篇
  2011年   2345篇
  2010年   2121篇
  2009年   2207篇
  2008年   2210篇
  2007年   2234篇
  2006年   2032篇
  2005年   1824篇
  2004年   1438篇
  2003年   1367篇
  2002年   1044篇
  2001年   1094篇
  2000年   898篇
  1999年   755篇
  1998年   665篇
  1997年   578篇
  1996年   473篇
  1995年   489篇
  1994年   417篇
  1993年   325篇
  1992年   340篇
  1991年   281篇
  1990年   267篇
  1989年   200篇
  1988年   199篇
  1987年   215篇
  1986年   176篇
  1985年   203篇
  1984年   188篇
  1983年   117篇
  1982年   148篇
  1981年   133篇
  1980年   127篇
  1979年   130篇
  1978年   99篇
  1977年   107篇
  1976年   103篇
  1975年   85篇
  1973年   87篇
排序方式: 共有10000条查询结果,搜索用时 468 毫秒
1.
2.
This systematic review aims to summarize cognitive reserve (CR) evaluation approaches and to examine the role of seven selected modifiable lifestyle factors (diet, smoking, alcohol consumption, physical activity, cognitive leisure activity, sleep, and meditation) in mitigating the impacts of age- or disease-related brain changes on cognition. Eighteen population-based English empirical studies were included. We summarize the study designs and identify three CR models that were broadly used in these studies, including a residual model assessing lifestyle factors in relation to unexplained variance in cognition after accounting for brain markers, a moderation model testing whether lifestyle factors moderate the relationship between brain status and cognition, and a controlling model examining the associations between lifestyle factors and cognition when controlling for brain measures. We also present the findings for the impact of each lifestyle factor. No studies examined diet, sleep, or meditation, and only two studies focused on smoking and alcohol consumption each. Overall, the studies suggest lifestyle activity factors (physical and cognitive leisure activities) may contribute to CR and attenuate the damaging impact of brain changes on cognition. Standardized measurements of lifestyle factors and CR are needed, and mechanisms underlying CR need to be further addressed as well.  相似文献   
3.
总结1例重型弥漫性轴索损伤伴肺挫裂伤患者的肺康复护理经验。护理要点包括:组建多学科肺康复管理团队,实施个性化呼吸支持与降阶梯序贯氧疗护理,精准廓清呼吸道,开展一体化的早期肺功能康复锻炼。经过多学科团队合作,患者入院后第12天撤离呼吸机,第17天拔除气管插管,第20天下床活动,第37天顺利出院,随访6个月,患者恢复良好。  相似文献   
4.
ObjectiveTo provide consensus on how to plan, organize and implement exercise-based injury prevention program (IPP) in sports.DesignDelphi.SettingLimeSurvey platform.ParticipantsExperienced sports physical therapists from the International Federation of Sports Physical Therapy member countries.Main outcome measuresFactors related to sports IPP planning, organization and implementation.ResultsWe included 305 participants from 32 countries. IPP planning should be based on an athlete's injury history, on pre-season screening results, and on injury rates (respectively, 98%, 92%, 89% agreement). In total 97% participants agreed that IPP organization should depend on the athlete's age, 93% on the competition level, and 93% on the availability of low-cost materials. It was agreed that IPP should mainly be implemented in warm-up sessions delivered by the head or strength/conditioning coach, with physical training sessions and individual physical therapy sessions (respectively, 94%, 92%, 90% agreement).ConclusionStrong consensus was reached on (1) IPP based on the athlete's injury history, pre-season screening and evidence-based sports-specific injury rates; (2) IPP organization based on the athlete's age, competition level, and the availability of low-cost materials and (3) IPP implementation focussing on warm-up sessions implemented by the strength/conditioning coach, and/or individual prevention sessions by the physical therapist.  相似文献   
5.
6.
7.
Vascular injuries that occur during traffic accidents are a commonly neglected aspect that can add more detail to the framework of a case. In this study, we analysed a case series of 150 traffic accidents, 39 of which were marked by microscopically identifiable vascular lesions. The purpose was to identify the presence of carotid injuries in individuals who died due to traffic accidents and had nonpenetrating trauma of the neck. We focused on the discrepancies regarding the macroscopical aspect and the histology and demonstrated how histological analysis of the carotids in cases of trauma can reveal injuries that are attributable to the trauma itself. We conducted a histological analysis of the lesions to describe their distribution and type and investigate potential correlations. The study offers insight on how to examine road accidents that involve traumatic injury of the carotid arteries. Indeed the main task of the forensic pathologist in the case of death is to establish the existence of a causal relationship between the micro- or macroscopic alterations observed in the autopsy and the traumatic event that led to the death of the subject. Thus, further morphological elements were provided to the forensic practitioners that may reveal injuries attributable to the trauma itself and should be evaluated in cases of trauma in traffic accidents.  相似文献   
8.
BackgroundExplosion fatalities are the severest type of violent crimes. These involve the use of explosive devices in terrorist like activities in confined spaces in civilian or military settings, with mass number of people present all around. A stark dearth of literature for the forensic interpretation of such catastrophes is astonishing.PurposeCharacterization of the pattern of the multitude of injuries in explosions in confined spaces as guide for investigations and growth of literature on this entity.MethodologyA review of the archives of the forensic examinations of mass fatalities due to an explosion in a metro car was undertaken. It was combined with the reconstruction of the events by developing a three-dimensional model of this incident that involved seventeen fatalities.ResultsAll the decedents showed differential pattern of fatal injuries under the influence of damaging explosion factors (DEFs). The causative forces were characterized as gas-detonation (in all the cases), damaging effect by shock waves (59% of the cases), and impact of fragmentation and collision of the body (thrown off) with nearby objects. Traumatic effect due to shrapnel as well as blunt force was noted in 82% of the cases. Gross destruction of head due to combined effect of gas-detonation and fragmentation was seen in 29% of the cases.ConclusionAn interpretation of the nature and pattern of injuries in confined space explosions can help to estimate the location of deceased/s with respect to the epicenter and the type of DEFs.  相似文献   
9.
Hip fractures are becoming increasingly common in a growing elderly population, and are associated with significant morbidity and mortality. Displaced intracapsular femoral neck fractures are usually treated with either total hip arthroplasty (THA) or hemiarthroplasty, although the indication for each operation remains an area for debate. THA has been associated with longer operative time, increased risk of dislocation and a slight increase in general complications compared with hemiarthroplasty. However, it has also been associated with a modest improvement in functional outcomes and quality of life. Guidelines have been created within the UK to aid the decision-making process based upon current available literature. The principal focus of these has been to identify patients suitable for THA, and include patients who are cognitively intact, mobile outside their home with the use of no more than one stick, and who are medically fit enough for the procedure. However, implant selection must also be taken into consideration in order to achieve the best outcomes for patients. Options for implants include use of dual mobility cups and choice of femoral head size in THA, bipolar versus unipolar hemiarthroplasty, and cemented versus uncemented implants. Further research is required into this area to make additional recommendations.  相似文献   
10.
胶质淋巴系统是一个主要由星形胶质细胞水通道蛋白4介导的依靠动脉、静脉周围血管间隙的脑脊液-脑组织液交换流动的系统,是阿尔茨海默病、脑卒中、帕金森病、失眠、抑郁症等脑病的共同特征,是一条新的脑代谢途径,可以清除包括β-淀粉样蛋白、乳酸在内的代谢产物。本文综合分析了全球有关胶质淋巴系统在脑部疾病的研究,得出:胶质淋巴系统可能为神经退行性疾病等发病机制和诊治策略研究带来新视角;胶质淋巴系统有望为一些脑部疾病诊断提供新的有效证据;胶质淋巴系统可能是脑部疾病治疗给药方式的新途径。  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-23

京公网安备 11010802026262号