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   16823篇
  免费   412篇
  国内免费   210篇
耳鼻咽喉   14篇
儿科学   102篇
妇产科学   58篇
基础医学   1348篇
口腔科学   241篇
临床医学   1012篇
内科学   612篇
皮肤病学   40篇
神经病学   480篇
特种医学   1365篇
外科学   10885篇
综合类   296篇
现状与发展   2篇
一般理论   1篇
预防医学   295篇
眼科学   34篇
药学   198篇
  2篇
中国医学   73篇
肿瘤学   387篇
  2023年   988篇
  2022年   1691篇
  2021年   1518篇
  2020年   1604篇
  2019年   1002篇
  2018年   618篇
  2017年   763篇
  2016年   774篇
  2015年   630篇
  2014年   1176篇
  2013年   897篇
  2012年   689篇
  2011年   508篇
  2010年   785篇
  2009年   628篇
  2008年   344篇
  2007年   344篇
  2006年   350篇
  2005年   239篇
  2004年   183篇
  2003年   189篇
  2002年   171篇
  2001年   166篇
  2000年   127篇
  1999年   138篇
  1998年   129篇
  1997年   91篇
  1996年   89篇
  1995年   66篇
  1994年   83篇
  1993年   55篇
  1992年   61篇
  1991年   56篇
  1990年   56篇
  1989年   35篇
  1988年   30篇
  1987年   14篇
  1986年   12篇
  1985年   21篇
  1984年   14篇
  1983年   5篇
  1982年   14篇
  1981年   10篇
  1980年   11篇
  1979年   10篇
  1978年   7篇
  1977年   7篇
  1975年   7篇
  1974年   9篇
  1973年   5篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
《Arthroscopy》2022,38(10):2930-2938
Hip–spine syndrome refers to concurrent hip and spine pathology with overlapping symptoms. Most of the literature has studied it in relation to total hip arthroplasty literature and has been shown to increase dislocation risk. Lumbar spine and pelvic mobility have been studied less frequently in relation to nonarthritic pathologic hip states. Understanding the biomechanical relationship between the lumbar spine, pelvis, and hip can help elucidate how hip–spine syndrome affects the nonarthritic hip and how it impacts outcomes of hip arthroscopy. Changes in lumbar spine motion may be the reason certain predisposed patients develop symptomatic femoroacetabular impingement (FAI) or ischiofemoral impingement. Some athletes may be “hip users” with a low pelvic incidence, making them more reliant on hip motion due to less-intrinsic lumbopelvic motion. When these patients have FAI morphology, their increased reliance on hip motion makes them prone to experiencing femoroacetabular contact and concurrent symptoms. Other athletes may be “spine users,” with larger pelvic incidence and more baseline lumbopelvic motion, making them less reliant on hip motion and therefore less prone to experiencing hip impingement even with hip FAI morphology. Hip–spine syndrome also appears to have an impact on patient selection, role of nonoperative treatment, and hip arthroscopy surgical outcomes. Identifying patients with concurrent pathology may allow surgeons to recommend targeted physical therapy or counsel patients better on their expectations after surgery.  相似文献   
993.
《Arthroscopy》2022,38(5):1396-1397
Treatment of recurrent anterior shoulder instability has gained significant interest in recent years and involves evaluation of both glenoid and humeral sided bone loss. Decision making is more complex in patients with significant humeral or glenoid bone defects or in those who underwent previous instability surgery. Appropriate assessment of the glenoid track is necessary as “off track” lesions typically require treatments beyond arthroscopic labral repair alone. In those with significant humeral or glenoid sided bone loss, the authors recommend three-dimensional computed tomography in addition to magnetic resonance imaging for accurate evaluation. The Glenoid Track Instability Management Score is a useful guide to help direct treatment by using the glenoid track as well as other known risk factors for recurrence. In circumstances with significant glenoid bone loss, typically over 20%, a coracoid transfer such as the Latarjet is recommended. In patients that previously failed a coracoid transfer, the authors recommend a distal tibia allograft; however, distal clavicle and iliac crest autograft have also been reported to have high success rates. In those with large Hill-Sachs lesions, remplissage or bone grafting are recommended. An estimation of the postoperative glenoid track after glenoid bone augmentation is required for appropriate Hill-Sachs lesion treatment. The authors typically recommend against revision instability surgical treatment with arthroscopic repair alone.  相似文献   
994.
《Arthroscopy》2022,38(9):2669-2671
The arena of hip arthroscopy has seen leaps in practices over the past decade, evolving from surgical debridement of the labrum to improvements in techniques which now allow repair, augmentation, and circumferential reconstruction. But as the operating theater continues to change its act, so too must the preoperative choreography. Recent advancements in the understanding of preoperative risk factors for failure of primary labral repair have identified the diminutive or hypoplastic labra on prescreening magnetic resonance imaging as a negative predictor of success. While this quantitative assessment predicts the anatomical coverage of the labrum, we are still limited in our ability to qualify the latter’s tissue substance preoperatively. Ossified or degenerative labra may not have the inherent functional capacity to restore the suction seal of the hip in a primary repair setting. If the applause from the audience fails to reach a significant threshold, we must rethink our act, and that begins with the choreography. The next step in hip arthroscopy is determining if a primary augmentation or reconstruction, in lieu of primary repair, warrants further consideration. Until we develop reliable methods of quantifying and qualifying the labral tissue, both preoperatively and optimally, we should establish backup for surprises encountered while on the “stage.”  相似文献   
995.
996.
997.
998.
《Injury》2022,53(4):1368-1374
ObjectivesHigh energy long bone fractures with critical bone loss are at risk for nonunion without strategic intervention. We hypothesize that a synthetic membrane implanted at a single stage improves bone healing in a preclinical nonunion model.MethodsUsing standard laboratory techniques, microspheres encapsulating bone morphogenic protein-2 (BMP2) or platelet derived growth factor (PDGF) were designed and coupled to a type 1 collagen sheet. Critical femoral defects were created in rats and stabilized by locked retrograde intramedullary nailing. The negative control group had an empty defect. The induced membrane group (positive control) had a polymethylmethacrylate spacer inserted into the defect for four weeks and replaced with a bare polycaprolactone/beta-tricalcium phosphate (PCL/β-TCP) scaffold at a second stage. For the experimental groups, a bioactive synthetic membrane embedded with BMP2, PDGF or both enveloped a PCL/β-TCP scaffold was implanted in a single stage. Serial radiographs were taken at 1, 4, 8, and 12 weeks postoperatively from the definitive procedure and evaluated by two blinded observers using a previously described scoring system to judge union as primary outcome.ResultsAll experimental groups demonstrated better union than the negative control (p = 0.01). The groups with BMP2 incorporated into the membrane demonstrated higher average union scores than the other groups (p = 0.01). The induced membrane group performed similarly to the PDGF group. Complete union was only demonstrated in groups with BMP2-eluting membranes.ConclusionsA synthetic membrane comprised of type 1 collagen embedded with controlled release BMP2 improved union of critical bone defects in a preclinical nonunion model.  相似文献   
999.
《Injury》2022,53(1):190-197
BackgroundMechanical ventilation of trauma patients is common, and many will require a higher than normal fraction of inspired oxygen (FiO2) to avoid hypoxaemia. The primary objective of this study was to assess the association between FiO2 and all-cause, one-year mortality in intubated trauma patients.MethodsAdult trauma patients intubated in the initial phase post-trauma between 2015 and 2017 were retrospectively identified. Information on FiO2 during the first 24 hours of hospitalisation and mortality was registered. For each patient the number of hours of the first 24 hours exposed to an FiO2 ≥ 80%, ≥ 60%, and ≥ 40%, respectively, were determined and categorised into exposure durations. The associations of these FiO2 exposures with mortality were evaluated using Cox regression adjusting for age, sex, body mass index (BMI), Injury Severity Score (ISS), prehospital Glasgow Coma Scale (GCS) score, and presence of thoracic injuries.ResultsWe included 218 intubated trauma patients. The median prehospital GCS score was 6 and the median ISS was 25. One-year mortality was significantly increased when patients had received an FiO2 above 80% for 3-4 hours compared to <2 hours (hazard ratio (95% CI) 2.7 (1.3-6.0), p= 0.011). When an FiO2 above 80% had been administered for more than 4 hours, there was a trend towards a higher mortality as well, but this was not statistically significant. There was a significant, time-dependent increase in mortality for patients who had received an FiO2 ≥ 60%. There was no significant relationship observed between mortality and the duration of FiO2 ≥ 40%.ConclusionA fraction of inspired oxygen above 60% for more than 2 hours during the first 24 hours of admission was associated with increased mortality in intubated trauma patients in a duration-dependent manner. However, given the limitations of this retrospective study, the findings need to be confirmed in a larger, randomized set-up.  相似文献   
1000.
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