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   235071篇
  免费   14888篇
  国内免费   989篇
耳鼻咽喉   2523篇
儿科学   5989篇
妇产科学   4415篇
基础医学   29291篇
口腔科学   4320篇
临床医学   24055篇
内科学   49551篇
皮肤病学   3221篇
神经病学   23654篇
特种医学   10110篇
外国民族医学   13篇
外科学   37006篇
综合类   2536篇
现状与发展   1篇
一般理论   177篇
预防医学   16517篇
眼科学   5529篇
药学   15480篇
  1篇
中国医学   319篇
肿瘤学   16240篇
  2023年   1335篇
  2022年   2191篇
  2021年   5333篇
  2020年   3043篇
  2019年   5052篇
  2018年   6048篇
  2017年   4441篇
  2016年   4847篇
  2015年   5731篇
  2014年   8347篇
  2013年   11243篇
  2012年   17273篇
  2011年   18006篇
  2010年   10066篇
  2009年   9309篇
  2008年   15859篇
  2007年   16652篇
  2006年   16193篇
  2005年   16053篇
  2004年   15100篇
  2003年   13783篇
  2002年   13182篇
  2001年   1926篇
  2000年   1426篇
  1999年   2001篇
  1998年   2784篇
  1997年   2212篇
  1996年   1922篇
  1995年   1761篇
  1994年   1527篇
  1993年   1493篇
  1992年   978篇
  1991年   923篇
  1990年   782篇
  1989年   741篇
  1988年   676篇
  1987年   612篇
  1986年   635篇
  1985年   678篇
  1984年   908篇
  1983年   786篇
  1982年   1033篇
  1981年   964篇
  1980年   835篇
  1979年   464篇
  1978年   514篇
  1977年   446篇
  1976年   419篇
  1975年   314篇
  1974年   310篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Abstract Background: Primary shoulder hemiarthroplasty is an established treatment modality for complex fractures of the proximal humerus. Long-term functional outcome is often disappointing. However, little is known about social implications particularly in the elderly. Methods: A single-institution case series of consecutive geriatric patients (age > 70 years) treated with shoulder hemiarthroplasty for complex fractures of the proximal humerus between 1994 and 1997 was analysed. Postoperative morbidity, long-term function, radiological outcome and social implications were evaluated. Results: Seventy-seven patients fulfilled the study criteria. Median age at the time of operation was 80 years (range 70–93 years). Systemic and local postoperative complications were observed in 8% including 2 patients (3%) with revision surgery. Postoperative mortality was 1%. Forty-eight patients (62%) were available for follow-up (median 49 months, range 25–80 months), 22 (29%) died from causes unrelated to hemiarthroplasty before follow-up and 7 patients (9%) did not attend follow-up examination. Median Constant-Murley score was 41 points (range 17–77 points). Long-term results concerning pain were satisfying. The Oxford shoulder score ranged from 14 to 40 (median 30). Forty-one patients (85%) still lived in their original environment and managed their daily life independently despite poor shoulder function. Four patients (8%) lived in a retirement home and 3 (6%) in a nursery home. Eighty percent of our patients were still able to use public transportation, do the daily shopping and wash their whole body by themselves. Conclusion: Most patients managed their daily life independently despite poor shoulder function.  相似文献   
52.
OBJECTIVE: Pamidronate has been studied as a therapeutic drug for various osteopenic diseases. However, avascular osteonecrosis in the jawbone has been recently reported in patients receiving pamidronate. The objective of this study was to examine the effect of pamidronate on bone regeneration in a controlled animal model. MATERIALS AND METHODS: To determine the effect of parmidronate on bone healing in a local bony defect area, a rabbit calvarial bony defect model was used and poly L-lactide-co-glycolide (PLGA) used as a drug carrier material. Four defect groups were made in each rabbit calvaria and the defects were treated as follows: untreated bony defect (group 1), PLGA only (group 2), 2 mg of pamidronate with PLGA (group 3), and 3 mg of pamidronate with PLGA (group 4). Bone healing was evaluated by radiography and histology at 1, 2, 4, 6, and 8 weeks after surgery. RESULTS: In radiographic analysis, radiopacity was lower in pamidronate groups than non-operated rabbit calvarial bone at all observation points (P < .05). In histological analysis, the initial bone formation at 1 week was not different among groups, but it was much lower in the pamidronate groups than in the control or PLGA group after 2 weeks. Newly formed bone at 1 week underwent avascular necrosis after 2 weeks in both pamidronate groups. Avascular necrosis was not observed until 8 weeks in both topically applied pamidronate groups. CONCLUSION: Collectively, pamidronate inhibits bone healing in rabbit calvarial bony defect and it may explain the avascular necrosis of the jaws in patients receiving pamidronate.  相似文献   
53.
The purpose of the present study was to evaluate the haemostatic efficacy of fibrin sealant in patients with hereditary haemorrhagic telangiectasia (HHT) or Rendu-Osler-Weber disease suffering epistaxis. A retrospective observational study of patients with HHT who were admitted to an emergency room for anterior or posterior epistaxis during May 2000-March 2003. A total of 24 patients were evaluated, of whom 15 were managed with foam nasal packing during May 2000-March 2002 and another nine were treated during March 2002-March 2003 with 0.3 ml fibrin sealant spray (Quixil; Omrix, Belgium). The immediate and the distant results were compared. Immediate haemostasis was achieved in all seven patients treated with fibrin glue, with good healing of bleeding sites, no secondary bleeding, no inflammation, and no plaque or crists. Twelve months of follow-up monitoring (until October 2003) of atrophic changes of nasal mucosa, bleeding frequency and intensity proved absence of atrophy of nasal mucosa and decreased bleeding frequency. In this group, the bleeding episode duration averaged 2 min 35 s since the moment of admittance. In the nasal packing group, we found local swelling, pain, and slow healing of the bleeding site with accidental atrophy of nasal mucosa and no effect on further bleeding frequency and intensity. Removal of nasal packing frequently initiates secondary bleeding. The rates of these side effects were higher in comparison with the fibrin glue group. The bleeding episode duration was also longer. In patients with HHT suffering profuse epistaxis, fibrin glue is more effective and convenient for the patients as compared with foam nasal packing. It is also safer, since it lacks the complications that usually accompany packing as swelling, atrophy of the nasal mucosa, and secondary bleeding provoked by the removal of the pack.  相似文献   
54.
55.
An empirical investigation of the perceived role of robotics and artificial computer intelligence in the future of health care reveals factors favoring a positive attitude by health administrators. The study employed a two-part survey administered in late 1989 and early 1990 to health care managers in hospitals and nursing homes. Part One of the survey asked about the participant, his or her work habits and work environment. Part Two obtained a psychological profile of rationality vs. intuition in problem solving. Through bivariate and multivariate post hoc statistical tests, we discovered the following variables which significantly determined attitudes toward robotics and artificial computer intelligence: sex, number of employees supervised; perceptions of waste and inefficiency in the workplace; perceptions of time-consuming personnel problem; perceived need to make more efficient use of time, money, and facilities; and perceived favorable climate for innovation. Among the factors which did not have an effect on attitudes toward advanced technology were three measures of rationality vs. intuition in problem solving.  相似文献   
56.
Tuberculosis involving the soft tissue from adjacent bone or joint is well recognized. However, primary tuberculous pyomyositis, tuberculous bursitis, and tuberculous tenosynovitis are rare entities constituting 1% of skeletal tuberculosis. Tuberculous tenosynovitis involves most commonly the tendon sheaths of the hand and wrist, and tuberculous bursitis occurs most commonly around the hip. The greater trochanteric bursa and the greater trochanter are the most frequent sites of tuberculous bursitis. Cases of primary tuberculous pyomyositis and tenosynovitis of the tendons of the ankle and foot are seldom reported in the radiology literature. All imaging modalities-plain radiography, bone scan, computed tomography, and magnetic resonance imaging (MRI)--provide information that is helpful in determining therapy. MRI in particular, with its multiplanar capabilities and superb contrast of soft tissue, can demonstrate the extent of the soft tissue mass and access the adjacent bones and joints. However, MRI has no diagnostic specificity in regard to tuberculosis, and in nonendemic areas, biopsy is strongly recommended. All patients in this review were permanent residents of North America or Western Europe and were immunocompetent. Examples of atypical presentations of the above entities are demonstrated.  相似文献   
57.
58.
Michael Eisenhut 《International journal of infectious diseases》2007,11(4):365; author reply 365-365; author reply 366
  相似文献   
59.
    
We present our comments on the above article.  相似文献   
60.
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