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   2355367篇
  免费   171618篇
  国内免费   3343篇
耳鼻咽喉   32081篇
儿科学   76015篇
妇产科学   62778篇
基础医学   348736篇
口腔科学   63790篇
临床医学   211897篇
内科学   458626篇
皮肤病学   51832篇
神经病学   185824篇
特种医学   88170篇
外国民族医学   489篇
外科学   354538篇
综合类   47600篇
现状与发展   12篇
一般理论   876篇
预防医学   183162篇
眼科学   54513篇
药学   175401篇
  11篇
中国医学   4593篇
肿瘤学   129384篇
  2021年   19076篇
  2019年   19639篇
  2018年   27175篇
  2017年   20452篇
  2016年   22834篇
  2015年   25730篇
  2014年   36202篇
  2013年   54155篇
  2012年   74925篇
  2011年   79700篇
  2010年   47216篇
  2009年   44717篇
  2008年   74848篇
  2007年   79747篇
  2006年   80567篇
  2005年   78011篇
  2004年   74573篇
  2003年   71920篇
  2002年   69536篇
  2001年   108835篇
  2000年   111549篇
  1999年   93583篇
  1998年   27045篇
  1997年   23702篇
  1996年   24090篇
  1995年   22768篇
  1994年   20940篇
  1993年   19746篇
  1992年   72090篇
  1991年   70160篇
  1990年   68472篇
  1989年   65746篇
  1988年   60384篇
  1987年   59216篇
  1986年   55296篇
  1985年   53068篇
  1984年   39382篇
  1983年   33440篇
  1982年   19890篇
  1979年   35920篇
  1978年   25708篇
  1977年   21263篇
  1976年   20363篇
  1975年   21854篇
  1974年   26199篇
  1973年   24850篇
  1972年   23244篇
  1971年   22083篇
  1970年   20273篇
  1969年   19341篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis.  相似文献   
42.
43.
44.
45.
46.
47.
Abstract

Objective: To understand the origin of extremely high gonadotropin levels in a perimenopausal woman.

Methods: A 52-year-old woman with a 2?months of amenorrhea followed spontaneous menstrual cycles recovery was referred to our outpatient clinic with elevated follicle-stimulating hormone (FSH, 483 mUI/ml), luteinizing hormone (LH, 475 mUI/ml) and prolactin (PRL, 173?ng/ml). She was known to take levosulpiride. The gonadotropin levels did not fit with the clinical features.

Results: A gonadotroph tumor was ruled out. Further analysis confirmed constantly high FSH, LH and PRL levels. The measurements were repeated using different analytical platforms with different results. After serial dilutions, nonlinearity was present suggesting an immunoassay interference. After post-polyethylene glycol recovery, hormone levels appeared in the normal range. Anti-goat antibodies were recognized in the serum of the patient.

Conclusions: This case report shows a case of falsely abnormal high gonadotropin and PRL levels in a woman during menopause transition. In the clinical practice the evaluation of gonadotropin profile is not recommended at this age, but the abnormal levels stimulated further evaluation. An interference in the assay due to anti-goat antibodies resulted in abnormally high level of FSH and LH. A strict collaboration between clinicians and the laboratory is needed, when laboratory findings do not correspond to clinical findings.  相似文献   
48.
Vestibular function laboratories utilize a multitude of diagnostic instruments to evaluate a dizzy patient. Caloric irrigators, oculomotor stimuli, and rotational chairs produce a stimulus whose accuracy is required for the patient response to be accurate. Careful attention to everything from cleanliness of equipment to threshold adjustments determine on a daily basis if patient data are going to be correct and useful. Instrumentation specifications that change with time such as speed and temperature must periodically be checked using calibrated instruments.  相似文献   
49.
In 1963, Goffman argued that forming a group based on shared stigma may provide benefits. However, there is no empirical research on whether perception that a separate, unique, coherent group exists (i.e., group entitativity) influences coping, such as educating others or secrecy, for the stigmatized individual or his or her spouse. Further, little is known about how spouses influence each other in terms of promoting the education of others about a stigmatizing condition, especially when it comes to the role of believing that stigma-based groups, to which they may both belong, exist. This study provides a step toward bridging this gap in the research by applying the label management model in efforts to understand coping for couples in which one spouse is diagnosed with genetic mutations leading to alpha-1 antitrypsin deficiency (AATD). This study included 50 married couples in which one spouse is diagnosed with genetic mutations leading to alpha-1 antitrypsin deficiency (AATD). We found that group entitativity related to those with AATD counterbalanced the influence of genetic stigma on spouses’ intentions to keep the diagnosis secret or to educate others about it. Intrapersonal and interpersonal influences appeared among spouses. Attention is needed on the power of creating groups for stigmatized persons and their relatives. Indeed, people live within a dynamic world of group entities, and multiple social identities including spousal and familial. While attention has been paid to the diffusion of stigmas to loved ones, less has been paid to the uplift of group entities for them.  相似文献   
50.
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