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   1760709篇
  免费   127120篇
  国内免费   4376篇
耳鼻咽喉   23958篇
儿科学   58792篇
妇产科学   50221篇
基础医学   252045篇
口腔科学   49059篇
临床医学   154408篇
内科学   346299篇
皮肤病学   38869篇
神经病学   139918篇
特种医学   69280篇
外国民族医学   622篇
外科学   269057篇
综合类   40119篇
一般理论   615篇
预防医学   133679篇
眼科学   40439篇
药学   126857篇
  3篇
中国医学   3613篇
肿瘤学   94352篇
  2018年   18070篇
  2017年   14161篇
  2016年   15719篇
  2015年   17808篇
  2014年   24744篇
  2013年   38226篇
  2012年   50679篇
  2011年   53916篇
  2010年   32582篇
  2009年   30800篇
  2008年   51106篇
  2007年   54073篇
  2006年   54757篇
  2005年   53206篇
  2004年   51327篇
  2003年   49531篇
  2002年   48287篇
  2001年   80387篇
  2000年   82559篇
  1999年   69867篇
  1998年   19604篇
  1997年   17800篇
  1996年   17793篇
  1995年   16819篇
  1994年   15818篇
  1993年   14873篇
  1992年   55622篇
  1991年   53815篇
  1990年   52906篇
  1989年   50918篇
  1988年   46722篇
  1987年   46534篇
  1986年   44095篇
  1985年   42323篇
  1984年   31690篇
  1983年   26971篇
  1982年   16216篇
  1981年   14399篇
  1979年   29425篇
  1978年   20953篇
  1977年   17772篇
  1976年   16745篇
  1975年   17958篇
  1974年   21618篇
  1973年   20792篇
  1972年   19376篇
  1971年   17961篇
  1970年   16987篇
  1969年   15870篇
  1968年   14861篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
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   
6.
7.
8.
9.
10.

Background

Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.

Methods

A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD.

Results

Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events.

Conclusions

Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting.  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