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   2367569篇
  免费   176996篇
  国内免费   3405篇
耳鼻咽喉   32416篇
儿科学   76435篇
妇产科学   63123篇
基础医学   350820篇
口腔科学   64224篇
临床医学   213394篇
内科学   461628篇
皮肤病学   51966篇
神经病学   187163篇
特种医学   88769篇
外国民族医学   489篇
外科学   357681篇
综合类   47995篇
现状与发展   12篇
一般理论   869篇
预防医学   184430篇
眼科学   54845篇
药学   176647篇
  10篇
中国医学   4592篇
肿瘤学   130462篇
  2021年   19355篇
  2019年   19911篇
  2018年   27506篇
  2017年   20728篇
  2016年   23098篇
  2015年   26035篇
  2014年   36760篇
  2013年   54982篇
  2012年   76125篇
  2011年   80902篇
  2010年   47865篇
  2009年   45386篇
  2008年   75982篇
  2007年   80945篇
  2006年   81872篇
  2005年   79286篇
  2004年   75843篇
  2003年   73160篇
  2002年   70751篇
  2001年   109006篇
  2000年   111719篇
  1999年   93799篇
  1998年   27347篇
  1997年   23923篇
  1996年   24304篇
  1995年   22924篇
  1994年   21079篇
  1993年   19877篇
  1992年   72219篇
  1991年   70246篇
  1990年   68581篇
  1989年   65829篇
  1988年   60466篇
  1987年   59263篇
  1986年   55361篇
  1985年   53144篇
  1984年   39456篇
  1983年   33524篇
  1982年   20018篇
  1979年   35982篇
  1978年   25760篇
  1977年   21339篇
  1976年   20405篇
  1975年   21893篇
  1974年   26237篇
  1973年   24894篇
  1972年   23280篇
  1971年   22099篇
  1970年   20297篇
  1969年   19369篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
123.
124.
Background A high Mandard score implies a non-response to chemotherapy in oesophageal adenocarcinoma. However, some patients exhibit tumour volume reduction and a nodal response despite a high score. This study examines survival and recurrence patterns in these patients.Methods Clinicopathological factors were analysed using multivariable Cox regression assessing time to death and recurrence. Computed tomography-estimated tumour volume change was examined in a subgroup of consecutive patients.Results Five hundred and fifty-five patients were included. Median survival was 55 months (Mandard 1–3) and 21 months (Mandard 4 and 5). In the Mandard 4 and 5 group (332 patients), comparison between complete nodal responders and persistent nodal disease showed improved survival (90 vs 18 months), recurrence rates (locoregional 14.75 vs 28.74%, systemic 24.59 vs 48.42%) and circumferential resection margin positivity (22.95 vs 68.11%). Complete nodal response independently predicted improved survival (hazard ratio 0.34 (0.16–0.74). Post-chemotherapy tumour volume reduction was greater in patients with a complete nodal response (−16.3 vs −7.7 cm3, p = 0.033) with no significant difference between Mandard groups.Conclusion Patients with a complete nodal response to chemotherapy have significantly improved outcomes despite a poor Mandard score. High Mandard score does not correspond with a non-response to chemotherapy in all cases and patients with nodal downstaging may still benefit from adjuvant chemotherapy.Subject terms: Oesophageal cancer, Surgical oncology  相似文献   
125.
126.
127.
128.
129.
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.  相似文献   
130.
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   
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