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   15643篇
  免费   1366篇
  国内免费   250篇
耳鼻咽喉   65篇
儿科学   308篇
妇产科学   127篇
基础医学   1336篇
口腔科学   421篇
临床医学   2394篇
内科学   2241篇
皮肤病学   80篇
神经病学   490篇
特种医学   648篇
外国民族医学   1篇
外科学   3802篇
综合类   2644篇
预防医学   723篇
眼科学   150篇
药学   1248篇
  8篇
中国医学   351篇
肿瘤学   222篇
  2024年   37篇
  2023年   369篇
  2022年   542篇
  2021年   803篇
  2020年   736篇
  2019年   712篇
  2018年   665篇
  2017年   576篇
  2016年   580篇
  2015年   547篇
  2014年   1127篇
  2013年   984篇
  2012年   946篇
  2011年   983篇
  2010年   769篇
  2009年   749篇
  2008年   746篇
  2007年   755篇
  2006年   642篇
  2005年   508篇
  2004年   451篇
  2003年   350篇
  2002年   286篇
  2001年   260篇
  2000年   238篇
  1999年   218篇
  1998年   174篇
  1997年   175篇
  1996年   129篇
  1995年   136篇
  1994年   104篇
  1993年   103篇
  1992年   123篇
  1991年   88篇
  1990年   72篇
  1989年   74篇
  1988年   74篇
  1987年   60篇
  1986年   44篇
  1985年   68篇
  1984年   43篇
  1983年   41篇
  1982年   44篇
  1981年   28篇
  1980年   29篇
  1979年   13篇
  1977年   14篇
  1976年   14篇
  1975年   9篇
  1973年   7篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
BACKGROUNDGuillain-Barré syndrome (GBS) is a rare disorder that typically presents with ascending weakness, pain, paraesthesias, and numbness, which mimic the findings in lumbar spinal stenosis. Here, we report a case of severe lumbar spinal stenosis combined with GBS.CASE SUMMARYA 70-year-old man with a history of lumbar spinal stenosis presented to our emergency department with severe lower back pain and lower extremity numbness. Magnetic resonance imaging confirmed the diagnosis of severe lumbar spinal stenosis. However, his symptoms did not improve postoperatively and he developed dysphagia and upper extremity numbness. An electromyogram was performed. Based on his symptoms, physical examination, and electromyogram, he was diagnosed with GBS. After 5 d of intravenous immunoglobulin (0.4 g/kg/d for 5 d) therapy, he gained 4/5 of strength in his upper and lower extremities and denied paraesthesias. He had regained 5/5 of strength in his extremities when he was discharged and had no symptoms during follow-up.CONCLUSIONGBS should be considered in the differential diagnosis of spinal disorder, even though magnetic resonance imaging shows severe lumbar spinal stenosis. This case highlights the importance of a careful diagnosis when a patient has a history of a disease and comes to the hospital with the same or similar symptoms.  相似文献   
5.
《Dental materials》2020,36(1):119-134
ObjectiveThe aim of this systematic review and meta-analysis was to evaluate the effect of surface conditioning methods on the bond strength of industrial indirect composite blocks (ICs).MethodsBased on the PICOS strategy, the Medline via PubMed, Embase and Web of Science (ISI – Web of Knowledge) electronic databases were searched for peer-reviewed articles in both English and Chinese, with no publication year limit. In vitro studies evaluating the effects of surface conditioning on the bond strength of ICs were selected. The meta-analysis was conducted to calculate the mean difference between surface-conditioned ICs and unconditioned controls. Subgroup analysis was performed to evaluate the different surface conditioning methods, separately for polymer-infiltrated ceramic network (PICN) material and the ICs with dispersed fillers (ICDFs). Meta-analyses were performed with a random-effects model at a significance level of 0.05.Results and SignificanceFrom 802 relevant studies, 25 were selected for full-text analysis. Nineteen studies were eligible for inclusion in this systematic review, whereas 9 studies were included in the meta-analysis. A manual search of the principal periodicals specific to the area resulted in no additional articles. The meta-analysis indicated a significant difference in bond strength between the surface-conditioned ICs and controls under both non-aged and aged conditions. The combination of mechanical and chemical conditioning yielded the highest bond strength of ICs. This meta-analysis suggests that chemical etching followed by a universal primer and alumina air abrasion followed by a silane coupling agent could be considered the best strategy for optimizing the bond strength of PICN materials and ICDFs under aged conditions, respectively.  相似文献   
6.
BackgroundThe anatomic course of the phrenic nerve runs in the fascia covering the anterior scalene muscle. Interscalene blocks are commonly performed by an anesthesiologist for shoulder surgery, such as a rotator cuff repair, total shoulder replacement, humeral fracture, or other arm surgery. Phrenic nerve palsy or paralysis is a known complication from interscalene block and is covered in multiple case reports and series in both Anesthesia and Neurosurgical literature, but only one case report in the Emergency Medicine literature.Case ReportThis case involves a 57-year-old man who had an uncomplicated arthroscopic rotator cuff repair with placement of interscalene block under care of anesthesia. He was discharged with a pain pump in place and then subsequently presented to the Emergency Department (ED) later that same day for evaluation of dyspnea. Using point-of-care ultrasound, his right diaphragm did not appear to be moving. Chest x-ray study revealed an elevated right hemidiaphragm. He was diagnosed with iatrogenic right phrenic nerve paralysis from interscalene block.Why Should an Emergency Physician Be Aware of This?Emergent diagnosis of phrenic nerve paralysis in the ED is complicated by a distressed patient and need for quick intervention. Most formal tests for this diagnosis are not immediately available to emergency physicians. Ultrasound is a rapid and reproducible, noninvasive resource with high sensitivity and specificity, making it an ideal imaging modality for the emergent evaluation of possible phrenic nerve palsy or paralysis.  相似文献   
7.
《The surgeon》2022,20(1):16-40
Surgical Innovations are central to surgical progress, and have led to exponential growth in various fields of Surgery. Surgical Innovations in Lower and Middle Income Countries are the result of creativity of frontline health workers in search of simple, safe and ethical solutions for their unique challenges. The key lies in: ‘simplifying the idea/technique/device’ to find patients' needs-driven low-cost innovative surgical solutions; which can be used on a wider scale to achieve health equity for underserved populations. Local surgeons understand the difficulties and nuances of various problems and can provide local-evidence-based customized solutions for their patients' health problems. We developed a Surgical Innovation Ecosystem allowing us to see difficulties as opportunities, learn from everyone and conduct research on what is ‘important’ rather than what is ‘interesting’. Barriers to Surgical Innovations in Lower and Middle Income Countries are well known; however, a roadmap to overcome these barriers is now available. The right balance has to be found between encouraging creativity and innovation while maintaining ethical awareness and responsibility to patients. Introduction and adoption of Surgical Innovations are governed by evidence-based principles and have to undergo a rigorous and scientific evaluation. Science of Surgical Innovations has finally come of age and is getting its due recognition and the pioneering innovators are receiving the much needed appreciation and support.  相似文献   
8.
9.
S. G. Brearley  S. Varey  A. Krige 《Anaesthesia》2023,78(10):1249-1255
Adequate postoperative analgesia is a key element of enhanced recovery programmes. Thoracic epidural analgesia is associated with superior postoperative analgesia but can lead to complications. Rectus sheath catheter analgesia may provide an alternative. In a nested qualitative study (within a two-year randomised controlled trial) focussing on the acceptability, expectations and experiences of receiving the interventions, participants (n = 20) were interviewed 4 weeks post-intervention using a grounded theory approach. Constant comparative analysis, with patient and public involvement, enabled emerging findings to be pursued through subsequent data collection. We found no notable differences regarding postoperative acceptability or the experience of pain management. Pre-operatively, however, thoracic epidural analgesia was a source of anticipatory fear and anxiety. Both interventions resulted in some experienced adverse events (proportionately more with thoracic epidural analgesia). Participants had negative experiences of the insertion of thoracic epidural analgesia; others receiving the rectus sheath catheter lacked confidence in staff members' ability to manage the local anaesthetic infusion pump. The anticipation of the technique of thoracic epidural analgesia, and concerns about its impact on mobility, represented an additional, unpleasant experience for patients already managing an illness experience, anticipating a life-changing operation and dealing with concerns about the future. The anticipation of rectus sheath catheter analgesia was not associated with such anxieties. Patients' experiences start far earlier than the experience of the intervention itself through anticipatory anxieties and fears about receiving a technique and its potential implications. Complex pain packages can take on greater meaning than their actual efficacy in relieving postoperative pain. Future research into patient acceptability and experience should not focus solely on efficacy of pain relief but should include anticipatory fears, anxieties and experiences.  相似文献   
10.
BackgroundRecent reports have shown that the daily cumulative moment in the frontal plane (i.e., product of hip moment impulse in the frontal plane during the stance phase and mean steps per day) is a risk factor for hip osteoarthritis. This study aimed to clarify the effect of contralateral cane use on hip moment impulse in the frontal plane of the stance limb.MethodsThis study included 15 healthy subjects who walked under four experimental conditions: (1) without a cane and (2–4) contralateral cane use with 10%, 15%, and 20% body weight support (BWS), respectively. To maintain the same walking speed in all conditions, the cadence was set to 80 steps/min, and the step length was fixed. The hip moment impulses in the frontal plane (i.e., area under the hip ab-adduction moment waveform) and peak hip adduction moments in all conditions were calculated.ResultsContralateral cane use significantly decreased the hip moment impulse in the frontal plane and peak hip adduction moment compared to non-cane use. Moreover, the hip moment impulse in the frontal plane and peak hip adduction moment decreased significantly with increased cane BWS. There were no significant differences in walking speed, cadence, and step length between the four conditions.ConclusionContralateral cane use decreases the hip moment impulse in the frontal plane and peak hip adduction moment in the stance limb. These findings may help clarify how to delay the progression of hip osteoarthritis.  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