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   15090篇
  免费   839篇
  国内免费   148篇
耳鼻咽喉   96篇
儿科学   326篇
妇产科学   224篇
基础医学   1704篇
口腔科学   377篇
临床医学   1319篇
内科学   4783篇
皮肤病学   185篇
神经病学   1481篇
特种医学   608篇
外科学   2141篇
综合类   26篇
预防医学   493篇
眼科学   132篇
药学   652篇
中国医学   9篇
肿瘤学   1521篇
  2023年   126篇
  2022年   213篇
  2021年   409篇
  2020年   283篇
  2019年   346篇
  2018年   409篇
  2017年   330篇
  2016年   403篇
  2015年   427篇
  2014年   592篇
  2013年   803篇
  2012年   1146篇
  2011年   1202篇
  2010年   668篇
  2009年   685篇
  2008年   1064篇
  2007年   1125篇
  2006年   1032篇
  2005年   996篇
  2004年   989篇
  2003年   801篇
  2002年   720篇
  2001年   100篇
  2000年   71篇
  1999年   106篇
  1998年   123篇
  1997年   122篇
  1996年   91篇
  1995年   82篇
  1994年   63篇
  1993年   74篇
  1992年   49篇
  1991年   58篇
  1990年   43篇
  1989年   26篇
  1988年   27篇
  1987年   29篇
  1986年   34篇
  1985年   21篇
  1984年   29篇
  1983年   24篇
  1982年   17篇
  1981年   15篇
  1980年   14篇
  1978年   9篇
  1977年   8篇
  1972年   7篇
  1968年   7篇
  1967年   10篇
  1966年   8篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
AIMS: The aim of this study is to compare PUMA curves with different pathologic conditions causing bladder dysfunction in 158 men and 83 women. METHODS: PUMA results in terms of bladder outlet obstruction and detrusor contractility were compared in 92 men with benign prostatic hypertrophy (BPH) and p(ves) congruent with p(det) (i.e., p(abd) congruent with 0) with the results of the urodynamics operator's opinion, the provisional International Continence Society method, Abrams and Griffith's diagram, urethral resistence factor (URA), Sch?fer's diagram, and Watt factor. PUMA curves correlated reliably with different pathologic conditions such as obstructive BPH, orthotopic bladder, cystocele, the neurological bladder, and bladder diverticulum. Statistical analysis indicated excellent agreement between PUMA and URA; agreement with other methods was good in cases of obstruction and nonobstruction. In doubtful cases, as diagnosed by standard methods, PUMA agreed only with the Abrams and Griffith's diagram. PUMA and Wmax were in good agreement on detrusor con traction force. Agreement between PUMA and Sch?fer's diagram was excellent for patients with detrusor hypercontractility and good for patients with detrusor hypocontractility and normocontractility. PUMA is the only method applicable to women. It is easy to perform. When integrated with other diagnostic tests, it provides realistic data for diagnosis, medical or surgical therapy, and outcome.  相似文献   
4.
5.
6.
7.
Porcelain heart     
A 65-year-old hypertensive man with shortness of breath andatypical thoracic pain underwent coronary angiography for  相似文献   
8.
PURPOSE: The introduction of microsurgical instruments and magnification devices has brought advantages in root-end management and the application of root-end filling materials. The main purpose of this prospective clinical study was to monitor the outcome of ultrasonic root-end preparation using magnification loupes or an endoscope. Tooth location and the presence of post restoration were also examined as potentially affecting the outcome. MATERIALS AND METHODS: Teeth treated surgically showed a periradicular lesion of strictly endodontic origin. A total of 59 patients were included in the study, according to specific selection criteria. Following the reflection of a full mucoperiosteal tissue flap, residual soft tissues were curetted, root ends were resected, and root-end cavities were prepared ultrasonically with a zirconium nitrate tip, and zinc oxide EBA-reinforced cement root-end fillings were placed. Thirty-two root-end management procedures were performed using magnification loupes and 39 using an endoscope. All cases followed for a period of 1 year were classified into 3 groups (success, uncertain healing, and failure) according to radiographic and clinical criteria. RESULTS: Of the 71 teeth evaluated at 1-year follow-up, 67 teeth (92.95%) successfully healed, 3 teeth had uncertain healing, and 2 failed. In the group using endoscopy, 94.9% of successful healing was achieved, while for the other group, 90.6% was recorded. We found no statistically significant differences in treatment results related to the arch (P = .20), post restoration (P = .21), or type of magnification device (P = .08). CONCLUSIONS: In the present study, adherence to a strict endodontic surgical protocol and the use of modern surgical endodontic procedures, together with visual magnifications, resulted in an overall high success rate.  相似文献   
9.
10.
Respiratory syncytial virus (RSV) bronchiolitis is a very common infection in infants and, after the acute phase, a number of patients develop a reactive airway disease that lasts for years. Although the pathogenesis of the lung damage after RSV bronchiolitis is still largely unknown, previous studies suggest that leukotrienes may play an active part in it. The aim of this study was to measure leukotriene levels in the nasal lavage fluid (NLF) collected in infants during RSV bronchiolitis and 1 month later. Cysteinyl leukotrienes (Cys-LTs) and leukotriene B(4) (LTB(4)) were measured in the NLF of 22 infants with their first episode of RSV bronchiolitis and 16 healthy infants. A second NLF sample was collected to measure leukotriene levels 1 month after the acute disease. NLF Cys-LT levels were significantly higher in infants with RSV bronchiolitis than in healthy controls [950 pg/ml (285.5-2155.9) vs. 110.5 pg/ml (66.5-451.3), p = 0.01], and they remained so a month after the acute infection (p = 0.02). A subanalysis showed no difference in Cys-LTs concentrations, either between bronchiolitis infants with and without a family history of atopy, or between those with and without passive exposure to cigarette smoke. No significant difference was found between the LTB(4) levels measured in the bronchiolitis cases and the control children. Cys-LTs are significantly increased in the NLF of infants with acute RSV bronchiolitis, and remain so at 1-month follow-up, suggesting a possible role of these eicosanoids in the pathogenesis of the disease.  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