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   2699968篇
  免费   188823篇
  国内免费   7836篇
耳鼻咽喉   35714篇
儿科学   88011篇
妇产科学   74207篇
基础医学   379883篇
口腔科学   73308篇
临床医学   241631篇
内科学   538842篇
皮肤病学   65401篇
神经病学   222969篇
特种医学   102807篇
外国民族医学   739篇
外科学   399116篇
综合类   50973篇
现状与发展   5篇
一般理论   983篇
预防医学   210120篇
眼科学   59572篇
药学   196494篇
  8篇
中国医学   5729篇
肿瘤学   150115篇
  2021年   21844篇
  2019年   22759篇
  2018年   33021篇
  2017年   24932篇
  2016年   28517篇
  2015年   32056篇
  2014年   43285篇
  2013年   64576篇
  2012年   87666篇
  2011年   92354篇
  2010年   54843篇
  2009年   51957篇
  2008年   85292篇
  2007年   90532篇
  2006年   91869篇
  2005年   87774篇
  2004年   84319篇
  2003年   81184篇
  2002年   78107篇
  2001年   130422篇
  2000年   133549篇
  1999年   112271篇
  1998年   31665篇
  1997年   28150篇
  1996年   28479篇
  1995年   27599篇
  1994年   25253篇
  1993年   23594篇
  1992年   86293篇
  1991年   82635篇
  1990年   79877篇
  1989年   76988篇
  1988年   70418篇
  1987年   68902篇
  1986年   64485篇
  1985年   61400篇
  1984年   45617篇
  1983年   38493篇
  1982年   22784篇
  1981年   20275篇
  1979年   39753篇
  1978年   28001篇
  1977年   23825篇
  1976年   22021篇
  1975年   23405篇
  1974年   27591篇
  1973年   26228篇
  1972年   24558篇
  1971年   22723篇
  1970年   20916篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
We present a patient with both dynamic left ventricular outflow tract obstruction and valvular aortic stenosis. The aortic valve was calcified, and velocities and gradients measured by continuous‐wave Doppler met standard criteria for severe aortic stenosis. The increased subvalvular velocities invalidated assumptions of the simplified Bernoulli equation; correction using the longer form of the Bernoulli equation suggested a lower but still significant gradient. The complex shape of the subvalvular spectral Doppler envelope indicated supranormal systolic function and dynamic left ventricular outflow obstruction. Left heart catheterization with an end‐hole catheter was required to determine the subvalvular and valvular components of the obstruction.  相似文献   
103.
104.
105.
106.
107.
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   
108.
Acute lung injury (ALI) caused by systemic inflammatory response remains a leading cause of morbidity and mortality in critically ill patients. Management of patients with sepsis is largely limited to supportive therapies, reflecting an incomplete understanding of the underlying pathophysiology. Furthermore, there have been limited advances in the treatments for ALI. In this study, lung function and a histological analysis were performed to evaluate the impact of transient receptor potential vanilloid‐1 receptor (TRPV1) antagonist (capsazepine; CPZ) on the lipopolysaccharide (LPS)‐induced lung injury in mice. For this, adult mice pre‐treated with CPZ or vehicle received intraperitoneal injections of LPS or saline and 24 hr after, the mice were anaesthetized, and lung mechanics was evaluated. The LPS‐challenged mice exhibited substantial mechanical impairment, characterized by increases in respiratory system resistance, respiratory system elastance, tissue damping and tissue elastance. The pre‐treatment with CPZ prevented the increase in respiratory system resistance and decreased the increase in tissue damping during endotoxemia. In addition, mice pre‐treated with CPZ had an attenuated lung injury evidenced by reduction on collapsed area of the lung parenchyma induced by LPS. This suggests that the TRPV1 antagonist capsazepine has a protective effect on lung mechanics in ALI during endotoxemia and that it may be a target for enhanced therapeutic efficacy in ALI.  相似文献   
109.
110.
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