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   2786篇
  免费   151篇
  国内免费   21篇
耳鼻咽喉   28篇
儿科学   91篇
妇产科学   49篇
基础医学   276篇
口腔科学   263篇
临床医学   240篇
内科学   574篇
皮肤病学   20篇
神经病学   156篇
特种医学   88篇
外科学   474篇
综合类   21篇
一般理论   1篇
预防医学   359篇
眼科学   14篇
药学   220篇
中国医学   1篇
肿瘤学   83篇
  2023年   5篇
  2022年   6篇
  2021年   41篇
  2020年   31篇
  2019年   45篇
  2018年   50篇
  2017年   41篇
  2016年   44篇
  2015年   38篇
  2014年   70篇
  2013年   149篇
  2012年   153篇
  2011年   174篇
  2010年   90篇
  2009年   78篇
  2008年   187篇
  2007年   199篇
  2006年   184篇
  2005年   196篇
  2004年   191篇
  2003年   198篇
  2002年   183篇
  2001年   40篇
  2000年   25篇
  1999年   56篇
  1998年   48篇
  1997年   45篇
  1996年   38篇
  1995年   21篇
  1994年   28篇
  1993年   28篇
  1992年   22篇
  1991年   26篇
  1990年   18篇
  1989年   10篇
  1988年   13篇
  1987年   8篇
  1986年   7篇
  1985年   17篇
  1984年   17篇
  1983年   12篇
  1982年   19篇
  1981年   24篇
  1980年   14篇
  1979年   10篇
  1978年   12篇
  1976年   7篇
  1975年   6篇
  1974年   5篇
  1966年   4篇
排序方式: 共有2958条查询结果,搜索用时 593 毫秒
41.
42.
This study evaluates the suitability of Xpert HPV (Cepheid, Sunnyvale, CA, USA) test for cervical and tonsillar formalin‐fixed paraffin‐embedded (FFPE) tissue samples as compared to the tests currently used in diagnostics. Cervical biopsies and liquid cytology (LC) samples were collected from 48 women attending colposcopy. Biopsies were processed for histology and tested for hrHPV using Xpert HPV. LC samples were tested using Xpert and Hybrid Capture 2 (HC2; Qiagen, Hilden, Germany) tests. Also 29 archived tonsillar carcinoma samples were tested using Xpert, and the results were compared with histology and immunohistochemical p16INK4a (p16) staining. Among valid cervical LC samples 46.8% were hrHPV positive using Xpert test and 55.3% with HC2. The sensitivity of Xpert was 84.6% as compared to HC2, and overall test concordance was 91.5%. Test concordance between valid Xpert results from biopsies and LC samples was 84.6%. Among valid tonsillar samples 70.4% were hrHPV positive, and concordance of 96.3% was found between Xpert and p16 staining. To conclude, Xpert HPV test cartridge provides a convenient platform to test individual samples, including FFPE samples. Further studies are needed to establish whether test sensitivity is sufficient to reliably differentiate between hrHPV positive and hrHPV negative head and neck carcinomas.  相似文献   
43.
44.
The effect of sampling site and proximity of malignant tumor on the relative fatty acid composition of human breast adipose tissue was studied in 10 cases of breast cancer. The four anatomic quadrants of breast did not statistically significantly differ from each other in relation to any of the 30 fatty acids studied. Proximity of the malignant tumor did not affect the relative fatty acid composition of fat when compared with more distant sampling sites. Representative samples of breast adipose tissue for fatty acid composition analysis can be obtained from tissue adjacent to the tumor.  相似文献   
45.
The aim was to study the determinants of preventive oral health care need among community‐dwelling old people. The study population consisted of 165 participants, a subpopulation in the Geriatric Multidisciplinary Strategy for Good Care of Elderly People (GeMS) study. Fifty‐five percent of the edentate participants with full dentures and 82% of the dentate had a need for preventive oral health care. In the total study population, the need for preventive care was associated with co‐morbidity (measured by means of the Modified Functional Co‐morbidity Index) odds ratios (OR) 1.2 (confidence intervals [CI] 1.0–1.5), being pre‐frail or frail, OR 2.5 (CI 1.2–5.1), presence of natural teeth, OR 4.8 (CI 2.2–10.4), and among dentate participants, the use of a removable partial denture, OR 12.8 (CI 1.4–114.4). Primary care clinicians should be aware of the high need for preventive care and the importance of nonoral conditions as determinants of preventive oral health care need.  相似文献   
46.
This is the first prospective follow-up study to describe the effects of oral alendronate medication on neurofibromatosis 1 (NF1)-related osteoporosis. NF1 is a neurocutaneous skeletal syndrome associated with increased fracture risk and high frequency of osteopenia and osteoporosis. Alendronate is a bisphosphonate drug which inhibits the function of bone-resorbing osteoclasts, ultimately leading to an increase in bone mineral density (BMD) and reduction in fracture risk. However, in vitro studies have shown that NF1 osteoclasts display insensitivity to apoptotic signals caused by bisphosphonates. Our aim was to monitor the effects of alendronate medication in patients with NF1. Five men and one woman, aged 28–76 years, with NF1-related osteoporosis were enrolled to the study. Study participants did not have other conditions and were not taking any medication known to affect bone. The medication included a weekly dose of 70 mg alendronate and a daily 20 μg vitamin D supplementation. After 23 months of follow-up, BMD was increased in five out of six patients, but the increase was not statistically significant. Serum levels of the bone turnover markers CTX and PINP were reduced, suggesting slower bone remodeling, as expected. An unexpected result was that serum levels of the osteoclast activity marker TRAP5b did not change during the follow-up. One new stress fracture of the tibia was documented during the alendronate therapy. Even though the study group was small, the findings of the current study (one new fracture and one patient with decreased BMD) call for a larger study to assess the efficacy of bisphosphonates in NF1-related osteoporosis.  相似文献   
47.
Objective : The purpose of the present study was to establish whether pump prime aprotinin could influence soluble adhesion molecules in patients undergoing elective coronary artery bypass surgery. Design : Thirty patients admitted for first-time elective coronary artery bypass surgery were randomized into control or aprotinin groups. Patients in the aprotinin group received 280 mg of aprotinin in the pump prime. Plasma levels of soluble adhesion molecules were analyzed perioperatively. Results : There were no significant changes in plasma sE-selectin after the operation in either group. Plasma sP-selectin increased significantly up to 20 h after reperfusion to the myocardium. Plasma sICAM-1 decreased in the early stage after cardiopulmonary bypass (CPB), then recovered at 4 h after reperfusion and a significant increase in sICAM-1 was observed 20 h later. There were no significant differences between the groups in postoperative changes in sP-selectin ( p = 0.21) and sICAM-1 ( p = 0.91). Conclusion : Pump prime aprotinin did not influence plasma levels of E-selectin, P-selectin and ICAM-1 in the present patients. The present results do not support the concept of an anti-inflammatory effect of pump prime aprotinin.  相似文献   
48.
49.
50.
A total of 85 Finnish alcohol-dependent subjects and 53 controls were studied with panoramic radiography. The aim was to study the possible associations between prolonged alcohol consumption and dental health. The mean number of teeth, caries lesions, endodontic treatments, periapical lesions, marginal bone loss, and periodontal infrabony pockets was studied. The subjects met the diagnostic criteria of alcohol dependence as set out in DSM-IV and ICD-10. The control group comprised social drinking volunteers with an AUDIT score &#104 8. For the final results the subjects were divided into groups on the basis of sex and age. The social backgrounds of the subjects were similar, except for employment and smoking. The results show significantly fewer teeth and more caries in the alcoholic group. There was a tendency for the alcoholics <45 years of age to have more endodontically treated teeth than the controls, but no difference in the number of periapical lesions in endodontically treated teeth was found. Horizontal bone loss and the presence of calculus were more frequent in alcoholic men than in alcoholic women. Significantly more horizontal bone loss was observed in the group of alcoholic nonsmokers than in nonalcoholic nonsmokers. In the nonsmoking groups alcoholics had significantly more periodontal destruction than the nonsmoking controls. We conclude that radiological dental health among individuals dependent on alcohol is weakened by more caries, more horizontal bone loss, and more numerous vertical infrabony pockets than social drinkers.  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