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   100914篇
  免费   7002篇
  国内免费   520篇
耳鼻咽喉   1238篇
儿科学   2371篇
妇产科学   1484篇
基础医学   12919篇
口腔科学   2379篇
临床医学   9930篇
内科学   22129篇
皮肤病学   1560篇
神经病学   9450篇
特种医学   4057篇
外国民族医学   1篇
外科学   16692篇
综合类   928篇
一般理论   194篇
预防医学   6965篇
眼科学   2016篇
药学   6159篇
中国医学   231篇
肿瘤学   7733篇
  2023年   904篇
  2022年   1553篇
  2021年   3373篇
  2020年   1880篇
  2019年   2926篇
  2018年   3407篇
  2017年   2430篇
  2016年   2622篇
  2015年   2972篇
  2014年   4079篇
  2013年   5219篇
  2012年   7884篇
  2011年   7986篇
  2010年   4424篇
  2009年   3850篇
  2008年   6603篇
  2007年   6380篇
  2006年   6170篇
  2005年   6102篇
  2004年   5477篇
  2003年   5037篇
  2002年   4500篇
  2001年   726篇
  2000年   602篇
  1999年   797篇
  1998年   935篇
  1997年   743篇
  1996年   599篇
  1995年   587篇
  1994年   481篇
  1993年   480篇
  1992年   450篇
  1991年   396篇
  1990年   360篇
  1989年   338篇
  1988年   353篇
  1987年   325篇
  1986年   334篇
  1985年   327篇
  1984年   380篇
  1983年   334篇
  1982年   366篇
  1981年   355篇
  1980年   273篇
  1979年   169篇
  1978年   208篇
  1977年   190篇
  1976年   147篇
  1975年   142篇
  1974年   144篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy.  相似文献   
82.
83.
84.
85.
OBJECTIVE: The surgical treatment of epistaxis associated with hereditary hemorrhagic telangiectasia (HHT) is varied. Laser therapy is often inadequate for larger complex lesions. This study sought to determine if bipolar cautery can be effectively and safely used in treating HHT-associated epistaxis. STUDY DESIGN AND SETTING: Records from all patients with HHT treated surgically over 8 years were reviewed retrospectively. Outcomes or complications were noted in the clinic on follow-up evaluation. RESULTS: Twenty-seven patients with HHT who underwent surgical treatment of epistaxis were evaluated; 18 were treated with bipolar cautery. Forty-two separate bipolar treatments were performed. No new septal perforations or synechiae were noted. Twenty-two of 42 treatments were coupled with ancillary laser treatments. The bipolar was also used as the sole technique in 20 procedures. CONCLUSION: Bipolar electrocautery is a safe and effective tool for the intraoperative control of HHT-related epistaxis. SIGNIFICANCE: Bipolar electrocautery may be used as an adjunct to laser techniques or as a stand-alone technique. EBM RATING: C-4.  相似文献   
86.
Abstract:  We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function.  相似文献   
87.
OBJECTIVE: To determine whether bacterial cultures of the wounds of patients undergoing clean orthopedic surgery would help predict infection. METHODS: During 1 year, 1,256 cultures were performed for 1,102 patients who underwent clean orthopedic surgery. Results were analyzed to evaluate their ability to predict postoperative infection. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of the cultures were 38%, 92%, 7%, and 99%, respectively. CONCLUSIONS: Cultures performed during clean orthopedic surgery were not useful for predicting postoperative infection.  相似文献   
88.
Images in emergency medicine   总被引:1,自引:0,他引:1  
  相似文献   
89.
90.
BACKGROUND: A single-blind, randomized, comparative study was performed to evaluate the efficacy of pure chromated glycerin (CG), polidocanol (POL) 0.25% solution, and POL 0.25% foam (Monfreux technique) for treatment of telangiectasias and reticular leg veins. OBJECTIVE: To determine the relative efficacy and safety of two sclerosing agents and foam. METHOD: Of 150 randomized patients presenting comparable areas (lateral face of thigh) of telangiectasias and reticular leg veins, 147 could be evaluated by photographic assessment, patients' satisfaction score, and pain at injection sites. Internal and external agreement for the photographic assessment was good for two independent blinded experts. RESULTS: CG cleared vessels significantly better than POL solution or foam (p<0.002). The patients' satisfaction score was also higher in the CG group, although the difference did not reach statistical significance. CG was significantly more painful at injection sites. Other side effects were very few, precluding any statistical comparison. Foam was associated with more side effects (microthrombi, matting) than CG or POL solution. Three patients treated with POL foam experienced a transient visual disturbance. CONCLUSION: This study shows that CG is superior to POL solution and foam for sclerotherapy of leg telangiectasias.  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