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   70916篇
  免费   6042篇
  国内免费   1431篇
耳鼻咽喉   1135篇
儿科学   2081篇
妇产科学   870篇
基础医学   6529篇
口腔科学   1739篇
临床医学   10590篇
内科学   8759篇
皮肤病学   852篇
神经病学   13153篇
特种医学   1026篇
外国民族医学   3篇
外科学   3246篇
综合类   7999篇
现状与发展   6篇
一般理论   11篇
预防医学   9811篇
眼科学   609篇
药学   4847篇
  58篇
中国医学   3859篇
肿瘤学   1206篇
  2024年   318篇
  2023年   1931篇
  2022年   2469篇
  2021年   3676篇
  2020年   3632篇
  2019年   3255篇
  2018年   3210篇
  2017年   3018篇
  2016年   2993篇
  2015年   2696篇
  2014年   4753篇
  2013年   6100篇
  2012年   4034篇
  2011年   4288篇
  2010年   3370篇
  2009年   3138篇
  2008年   3156篇
  2007年   3094篇
  2006年   2576篇
  2005年   2134篇
  2004年   1905篇
  2003年   1837篇
  2002年   1370篇
  2001年   1140篇
  2000年   923篇
  1999年   871篇
  1998年   777篇
  1997年   666篇
  1996年   584篇
  1995年   507篇
  1994年   442篇
  1993年   390篇
  1992年   364篇
  1991年   295篇
  1990年   283篇
  1989年   203篇
  1988年   208篇
  1987年   198篇
  1986年   159篇
  1985年   230篇
  1984年   214篇
  1983年   161篇
  1982年   162篇
  1981年   127篇
  1980年   129篇
  1979年   90篇
  1978年   85篇
  1977年   58篇
  1976年   45篇
  1974年   30篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
阿尔茨海默病患者脑白质损害与认知功能的关系   总被引:4,自引:0,他引:4  
目的用磁共振扩散张量成像(DTI)研究阿尔茨海默病(AD)患者脑白质损害的特点及其与认知功能改变的相关性。方法对16例AD患者和12名年龄及性别相当的健康老年人行DTI、T1液体衰减反转恢复序列(FLAIR)及T2-FLAIR检查,测量胼胝体膝部和压部、内囊前肢和后肢、额颞顶枕叶白质的部分各向异性分数值(FA)和平均弥散度(MD),分析FA、MD值与简易精神状态量表(MMSE)评分之间的相关关系。结果AD患者胼胝体压部、额叶、顶叶、颞叶FA值分别为0.602±0.043、0.270±0.034、0.294±0.043、0.302±0.032,与健康老人组相比显著下降(P<0.05),且与MMSE评分呈正相关关系,而内囊前后肢、枕叶、胼胝体膝部的FA值则无明显变化(P>0.05);胼胝体压部、顶叶白质的MD值分别为(0.918±0.029)、(0.826±0.015)×10-9m2/s,与健康老人组相比显著升高(P<0.01),且与MMSE评分呈负相关,而内囊前后肢、额叶、颞叶、枕叶和胼胝体膝部的MD值则无明显变化(P>0.05)。结论AD患者表现为脑白质的选择性损害,且损害程度与认知功能密切相关;这种选择性损害反映了AD病理机制中皮质-皮质及皮质-皮质下联系的丢失;DTI技术可以用来监测疾病的进展情况及评价AD治疗药物的临床疗效。  相似文献   
32.
The frequency and pathophysiology of freezing of gait (FoG) in atypical parkinsonism is unknown. We analysed the frequency of FoG in postmortem-confirmed atypical parkinsonian disorders (APD) comprising corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Sixty-six patients with pathologically confirmed APD (CBD, n = 13; DLB, n = 14; MSA, n = 15; PSP, n = 24) formed the basis for a multicenter clinicopathological study. Clinical features at first and last clinical visit were abstracted from patient records on standardized forms following strict instructions. At the first visit (median 36 months after symptom onset), 24% of APD had FoG (CBD, 8%; DLB, 21%; PSP, 25%; MSA, 40%). Logistic regression analysis showed a significant association of FoG and urinary incontinence (P = 0.04) at first visit. At last visit, 47% of APD had FoG (CBD, 25%; PSP, 53%; DLB, 54%; MSA, 54%). Clinicopathological correlation based on routine postmortem examination failed to identify a consistent neuropathological substrate of FoG. This study demonstrates that (1) FoG is common in APD, and (2) urinary incontinence is significantly associated with FoG in these disorders. Whether FoG and urinary incontinence share similar neuropathological substrates remains to be determined by future studies.  相似文献   
33.
唐永明  张斌 《江苏医药》1997,23(12):833-835
采用ABC免疫组化染色法及单克隆抗体夹心法ELISA,同步检测了34例肾综合征出血热(HFRS)患者外周血T细胞亚群数量和血清白细胞介素2和4(IL-2、IL-4)水平。发现HFRS病程中各T细胞亚群数量均有不同程度的升高,其中CDS阳性T细胞在各病期均有升高。IL-4水平升高仅见于发热期.而IL-2的升高主要在低血压期和少尿期。病程中有CD4/CD8比值的下降甚至倒置。这种比值的变化与IL-2和IL-4的动态变化有一定的相关性。结果揭示,在HFRS发病机理中存在Thl型和Th2型免疫反应等多种免疫病理机制。  相似文献   
34.
Conceived of during the Vietnam war, the hypothesis that the perpetrators of atrocities could subsequently develop psychiatric disorders identical to those of their victims led to the emergence of a specific category: the self-traumatized perpetrator. While the United States was discovering that its soldiers had been involved in appallingly barbaric acts, psychiatry through the DSM-III post-traumatic stress disorder provided a more conciliatory response to the behavior of those veterans by shifting the political issue into the sphere of clinical debate. The author examines the origin, development and the subsequent exhaustion of this category from a strictly anthropological point of view. In this study, the category of self-traumatized perpetrator has been constructed on the basis of psychological knowledge and of various influencing external factors. In this sense, it can be viewed as transient category as far as psychiatric nosology is concerned, and is closely dependent on the outcome of the political and social issues that favored its emergence, and destined to disappear with them. In adopting the term coined by Ian Hacking, the author shows that the disorder observed in the case of the self-traumatized perpetrator is above all a “transient mental illness”  相似文献   
35.
36.
37.
38.
The Eating Disorder Inventory, Version 2 (EDI‐2) is a questionnaire used clinically and in research all over the world. EDI‐2 is cross‐culturally valid, yet normative values may depend on culture. Norms and reliability of the Danish version have to date been lacking, and will be presented in this article, comparing patients (N = 575) and controls (N = 881). Also, internal reliability of scales is tested for both groups. Differences between norms of the Danish and the North American version of EDI were small but significant for all scales except asceticism (eating disorder patients) and ineffectiveness, interpersonal distrust and maturity fears (normal controls). For both groups the internal consistency was >0.70 for all subscales except asceticism. Although differences across the eating disorder diagnostic groups were dubious, the EDI‐2 is useful to screen for eating problems in the general population as well as to rate progress and outcome among eating disorder patients. Copyright © 2009 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
39.
40.
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