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   2688篇
  免费   201篇
  国内免费   149篇
儿科学   42篇
妇产科学   3篇
基础医学   243篇
口腔科学   24篇
临床医学   272篇
内科学   116篇
皮肤病学   7篇
神经病学   159篇
特种医学   78篇
外科学   1364篇
综合类   388篇
现状与发展   1篇
预防医学   43篇
眼科学   145篇
药学   71篇
  1篇
中国医学   66篇
肿瘤学   15篇
  2024年   13篇
  2023年   91篇
  2022年   86篇
  2021年   152篇
  2020年   144篇
  2019年   95篇
  2018年   86篇
  2017年   123篇
  2016年   128篇
  2015年   114篇
  2014年   229篇
  2013年   300篇
  2012年   188篇
  2011年   191篇
  2010年   108篇
  2009年   113篇
  2008年   116篇
  2007年   119篇
  2006年   87篇
  2005年   85篇
  2004年   70篇
  2003年   45篇
  2002年   40篇
  2001年   22篇
  2000年   17篇
  1999年   25篇
  1998年   23篇
  1997年   18篇
  1996年   21篇
  1995年   21篇
  1994年   8篇
  1993年   29篇
  1992年   11篇
  1991年   10篇
  1990年   8篇
  1989年   7篇
  1988年   5篇
  1987年   11篇
  1986年   6篇
  1985年   4篇
  1984年   5篇
  1983年   8篇
  1982年   11篇
  1981年   11篇
  1980年   8篇
  1979年   7篇
  1978年   7篇
  1977年   3篇
  1976年   4篇
  1975年   5篇
排序方式: 共有3038条查询结果,搜索用时 15 毫秒
91.
Since 1986, the authors have been conducting conservative treatment for idiopathic scoliosis with the combination of brace treatment and physical treatment (side shift exercise and hitch exercise). A total of 328 female patients with adolescent idiopathic scoliosis who were at least 10 years of age at the first visit, with Cobb angle of 10° at the minimum and followed until after 15 years of age or skeletal maturity were included. The average Cobb angle was 32.4° and the average age was 13.8 years at the first visit. Surgery was recommended when curvature progressed to >50°. Twenty of 328 patients (6.1%) with more severe curves to begin with (mean Cobb angle at admission of 48.5?±?9.3°) progressed to 62.2?±?8.5° and were treated with spinal fusion by the age of 16.0?±?2.6 years. The remaining 308 patients, of comparable age at inception of treatment but with a smaller original mean Cobb angle (32.4?±?11.1°), showed no significant increase in magnitude of curvature (mean 33.6?±?11.5°) by the time of discharge (18.6?±?3.1 years). The fact that curvature magnitude was maintained at <35° means that these patients will have a good prognosis for avoiding dramatic progression during adulthood.  相似文献   
92.
The association of Neurofibromatosis type 1(NF1) and primary hyperparathyroidism (PHPT) is a well described but very rare entity. This association supports the hypothesis of a variant of multi-endocrine neoplasia syndrome. We report a 52-year-old woman with NF1, PHPT and spinal deformity. She had cutaneous lesions of neurofibromatosis. X-ray imaging has shown severe kyphoscoliosis and bone mineral density measurement has revealed severe osteoporosis. Significant increases in blood calcium and parathormon level were measured. Parathyroid adenoma was determined by ultrasound and MIBI scan. Hyperparathyroidism and hypercalcaemia resolved after surgical removal of adenoma. The general condition of the patient was improved significantly after two months of medical and physical therapy. All NF1 patients who have severe skeletal deformities, osteoporosis, and motor activity loss should be investigated for the concurrence of PHPT.  相似文献   
93.
94.
A new era in the surgical treatment of adolescent idiopathic scoliosis (AIS) opened with the introduction of pedicle screw instrumentation, which provides 3-column vertebral fixation and allows major deformity correction on the coronal, sagittal, and axial planes. A steep learning curve can be expected for spinal surgeons to become familiar with pedicle screw placement and correction techniques. Potential complications including injury to adjacent neural, vascular, and visceral structures can occur due to screw misplacement or pull-out during correction maneuvers. These major complications are better recognized as pedicle screw techniques become more popular and may result in serious morbidity and mortality. Extensive laboratory and clinical training is mandatory before pedicle screw techniques in scoliosis surgery are put to practice. Wider application, especially in developing countries, is limited by the high cost of implants. Refined correction techniques are currently developed and these utilize a lesser number of pedicle anchors which are strategically positioned to allow optimum deformity correction while reducing the neurological risk, surgical time, and blood loss, as well as instrumentation cost. Such techniques can be particularly attractive at a time when cost has major implications on provision of health care as they can make scoliosis treatment available to a wider population of patients. Pedicle screw techniques are currently considered the gold standard for scoliosis correction due to their documented superior biomechanical properties and ability to produce improved clinical outcomes as reflected by health-related quality-of-life questionnaires. Ongoing research promises further advances with the future of AIS treatment incorporating genetic counseling and possibly fusionless techniques.  相似文献   
95.
96.

Purpose

Adolescent idiopathic scoliotic (AIS) deformity induces excessive oxygen consumption correlated to a bilateral increase of lumbo-pelvic muscles timing activity (EMG) during gait. Wearing a brace, the usual treatment for AIS, by supporting the spine and the pelvis, would generate lumbo-pelvic muscular relaxation and consequently reduce excessive oxygen consumption. The purpose of this study was to evaluate the short-term effect of bracing on gait biomechanics in scoliotic spine when compared with normal braced spine.

Methods

Thirteen healthy volunteers were compared to 13 AIS girls. In both samples, gait analysis was assessed using a three-dimensional motion analysis, including synchronous kinematic, electromyographic, mechanical and energy measurements, first without brace, then wearing a brace.

Results

For scoliotic patients, comparison of in-brace and out-brace situations revealed a significant decrease of frontal pelvis (p < 0.001), hip (p < 0.001) and shoulder (p = 0.004) motion in brace associated with a significant reduction of pelvis rotation (p = 0.003). However, the brace did not change significantly the lumbo-pelvic muscle activity duration (EMG) or the mechanical and energetic parameters. Transversal pelvis motion was reduced by 39 % (p = 0.04), frontal hip and shoulder motions by 23 % (p = 0.004) and 30 % (p = 0.01) respectively, and energy cost of walking remained increased by 37 % in braced AIS girls relatively to braced healthy subjects. Mechanical and electromyographic variables were not significantly different between the two braced populations during gait except for the gluteus medius muscle that showed bilaterally an increase of duration of electrical activity in healthy subjects and contrarily a decrease in AIS patients (healthy: −3.5 ± 9.6 % of gait cycle vs. scoliotic: 3.7 ± 7.7 % of gait cycle; p = 0.04).

Conclusions

Bracing changed neither the oxygen consumption nor the timing of the lumbo-pelvic muscles activity in both groups during gait. However, in brace the timing activity of bilateral gluteus medius muscles tended to decrease in AIS patients and increase in healthy subjects. Moreover, braced AIS patients had more restricted frontal hips and shoulder motion as well as pelvis rotation than braced healthy subjects.  相似文献   
97.
98.

Purpose

To study family history in relation to curve severity, gender, age at diagnosis and treatment in idiopathic scoliosis.

Methods

A self-assessment questionnaire on family history of scoliosis was administered to 1,463 untreated, brace or surgically treated idiopathic scoliosis patients.

Results

Out of the 1,463 patients, 51 % had one or more relatives with scoliosis. There was no significant difference between females and males, nor between juvenile and adolescent study participants in this respect (p = 0.939 and 0.110, respectively). There was a significant difference in maximum curve size between patients with one or more relatives with scoliosis (median 35°, interquartile range 25) and patients without any relative with scoliosis (median 32°, interquartile range 23) (p = 0.022). When stratifying patients according to treatment (observation, brace treatment or surgery), we found that it was more common to have a relative with scoliosis among the treated patients (p = 0.011). The OR for being treated was 1.32 (95 % CI 1.06–1.64) when the patient had a relative with scoliosis, compared to not having.

Conclusions

Larger curve sizes were found in patients with a family history of scoliosis than in the ones without. No relation between family history and gender or between family history and age at onset of idiopathic scoliosis was found. Although the presence of a family history of scoliosis may not be a strong prognostic risk factor, it indicates that these patients are at higher risk of developing a more severe curve.  相似文献   
99.

Purpose

To investigate the long-term impacts of different posterior operations on curvature, neurological improvement and axial symptoms for multilevel cervical degenerative myelopathy (CDM), and to study the relationship among loss of cervical lordosis, recovery rate and axial symptom severity.

Methods

We retrospectively reviewed 98 patients with multilevel CDM who had undergone laminoplasty (Group LP, 36 patients), laminectomy (Group LC, 30 patients), or laminectomy with lateral mass screw fixation (Group LCS, 32 patients) between January 2000 and January 2005. Loss of curvature index (CI) was measured according to the preoperative and final follow-up radiographic parameters. The recovery rate was calculated based on the Japanese Orthopedic Association (JOA) score. Axial symptom severity was quantified by Neck Disability Index (NDI).

Results

Analysis of final follow-up data showed significant differences among the three groups regarding loss of CI (F = 41.46, P < 0.001) between preoperative and final follow-up JOA scores (P < 0.001), final follow-up JOA score (F = 7.81, P < 0.001), recovery rate (F = 12.98, P < 0.001) and axial symptom severity (χ2 = 18.04, P < 0.001). Loss of CI showed negative association with neurological recovery (r = −0.555, P < 0.001) and positive correlation with axial symptom severity (r = 0.696, P < 0.001).

Conclusions

Excellent neurological improvement was obtained by LP and LCS for patients with multilevel CDM, while loss of CI in groups LP and LC caused a high incidence of axial symptoms. Loss of CI was correlated with poor neurological recovery and axial symptom severity. Lateral mass screw fixation can effectively prevent loss of postoperative cervical curvature and reduce incidence of axial symptoms.  相似文献   
100.

Introduction

Decompression with fusion is usually recommended in patients with lumbar spinal stenosis (LSS) combined with degenerative lumbar scoliosis (DLS). However, elderly patients with LSS and DLS often have other comorbidities, and surgical treatment must be both safe and effective. The aim of this study was to investigate whether decompression surgery alone alleviates low back pain (LBP) in patients with LSS and DLS, and to identify the predictors of postoperative residual LBP.

Materials and methods

A total of 75 patients (33 males and 42 females) with a mean age of 71.8 years (range 53–86 years) who underwent decompression surgery for LSS with DLS (Cobb angle ≥ 10°) and had a minimum follow-up period of 1 year, were retrospectively reviewed using the Japanese Orthopaedic Association scoring system for the assessment of lumbar spinal diseases (JOA score). Radiographic measurements included coronal and sagittal Cobb angles, apical vertebral rotation (Nash-Moe method), and anteroposterior and lateral spondylolisthesis. Logistic regression analysis was performed to investigate the predictors of residual LBP after surgery.

Results

Forty-nine patients had preoperative LBP, of which 29 (59.1 %) experienced postoperative relief of LBP. Logistic regression analysis demonstrated that the degree of apical vertebral rotation on preoperative radiography was significantly associated with postoperative residual LBP (odds ratio, 8.16, 95 % confidence interval, 1.55–83.81, p = 0.011).

Conclusion

A higher degree of apical vertebral rotation may therefore be an indicator of mechanical LBP in patients with LSS and DLS. Decompression with fusion should be recommended in these patients.  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