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41.
ABSTRACT

The purpose of this study was to determine the effects of prolonged standing on gait characteristics in children with spastic cerebral palsy. Six children with spastic cerebral palsy participated in this study with an average age of 6.5 years (SD = 2.5, range = 4.0–9.8 years). A reverse baseline design (A-B-A) was used over a 9-week period. During phase A, the children received their usual physical therapy treatment. During phase B, children received the prolonged standing program three times per week, in addition to their usual physical therapy treatment. During phase A2, children received their usual physical therapy treatment. Gait analysis and clinical assessment of spasticity were performed before and after each phase. Analysis of variance (ANOVA) for repeated measurements was used to test for changes in gait measures across the four measurement sessions. Friedman's was used to test for changes in muscle tone (Modified Ashworth Scale) across the four measurement sessions. Stride length (p <.001), gait speed (p <.001), stride time (p <.001), stance phase time (p <.001), double support time (p <.003), muscle tone (p <.02), and peak dorsiflexion angle during midstance (p <.004) improved significantly following the intervention phase. The results of this study demonstrate that the gait pattern of children with cerebral palsy classified as level II or III on the Gross Motor Functional Classification System (GMFCS) improved by a prolonged standing program. However, these improvements were not maintained at 3 weeks. Further research is necessary with larger sample sizes to replicate these findings and determine specific “dosing” for standing programs to create long-lasting functional effects on gait.  相似文献   
42.
BackgroundGait and balance disorders are common in Parkinson's disease (PD) and major contributors to increased falling risk. Predictive and reactive adjustments can improve recovery performance after gait perturbations. However, these mechanisms have not been investigated in young-onset PD.ObjectiveWe aimed to investigate the effect of gait perturbations on dynamic stability control as well as predictive and reactive adaptability to repeated gait perturbations in young PD patients.MethodsFifteen healthy controls and twenty-five young patients (48 ± 5 yrs.) walked on a walkway. By means of a covered exchangeable element, the floor surface condition was altered to induce gait perturbations. The experimental protocol included a baseline on a hard surface, an unexpected trial on a soft surface and an adaptation phase with 5 soft trials to quantify the reactive adaptation. After the first and sixth soft trials, the surface was changed to hard, to examine after-effects and, thus, predictive motor control. Dynamic stability was assessed using the ‘extrapolated center of mass’ concept.ResultsPatients’ unperturbed walking was less stable than controls’ and this persisted in the perturbed trials. Both groups demonstrated after-effects directly after the first perturbation, showing similar predictive responses. However, PD patients did not improve their reactive behavior after repeated perturbations while controls showed clear locomotor adaptation.ConclusionsOur data suggest that more unstable gait patterns and a less effective reactive adaptation to perturbed walking may be a disease-related characteristic in young PD patients. These deficits were related to reduced ability to increase the base of support.  相似文献   
43.
BackgroundFreezing of gait (FOG) is a major concern for Parkinson's disease (PD) patients because it is a leading cause of falls and is associated with poor quality of life. The pathophysiology is unknown but it is hypothesized that it relates to cognitive abnormalities; particularly executive and visuospatial dysfunction. However, prior results have been discrepant. Pharmacologic subtypes of FOG include those that are responsive and unresponsive to levodopa.ObjectiveTo determine whether executive and visuospatial dysfunction are associated specifically with the levodopa unresponsive subtype of FOG.Methods135 PD subjects completed a single assessment included FOG questionnaire, UPDRS motor scale, comprehensive cognitive battery and measure of hallucinations. Analyses compared unresponsive (n = 16), responsive (n = 20) and no FOG (n = 99) subtypes.ResultsThe unresponsive subtype had a significantly older age of onset of PD than the responsive group (p = .03) and had worse motor scores (p = .003) than the no FOG group. Longer disease duration was associated with the responsive group compared to the no FOG group (p = .002). The unresponsive FOG group had significantly poorer visuospatial ability (p = .001) and executive functioning (p = .02) than both the no and responsive FOG subgroups. These latter groups were not significantly different. The responsive FOG group was associated with the presence of hallucinations.ConclusionAside from pharmacological differences, unresponsive FOG is associated with executive and visuospatial dysfunction implicating frontostriatal pathways while responsive FOG is associated with hallucinations suggesting involvement of posterior cortical regions. Further study and treatment of FOG should include appropriate subtype classification.  相似文献   
44.
Symptom relief of recalcitrant metatarsalgia can be achieved through surgical shortening of the affected metatarsal, thus decreasing plantar pressure. Theoretically an oblique metatarsal osteotomy can be oriented distal to proximal (DP) or proximal to distal (PD). We characterized the relationship between the amount of second metatarsal shortening, osteotomy plane, and plantar pressure. We hypothesized that the PD osteotomy is more effective in reducing metatarsal peak pressure and pressure time integral. We performed eight DP and eight PD second metatarsal osteotomies on eight pairs of cadaveric feet. A custom designed robotic gait simulator (RGS) generated dynamic in vitro simulations of gait. Second metatarsals were incrementally shortened, with three trials for each length. We calculated regression lines for peak pressure and pressure time integral vs. metatarsal shortening. Shortening the second metatarsal using either osteotomy significantly affected the metatarsal peak pressure and pressure time integral (first and third metatarsal increased, p < 0.01 and <0.05; second metatarsal decreased, p < 0.01). Changes in peak pressure (p = 0.0019) and pressure time integral (p = 0.0046) were more sensitive to second metatarsal shortening with the PD osteotomy than the DP osteotomy. The PD osteotomy plane reduces plantar pressure more effectively than the DP osteotomy plane. Published 2013 by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res 32:385–393, 2014.  相似文献   
45.
目的:观察健康人在步行过程中下肢运动学、动力学、地面反作用力以及表面肌电信号的重测信度。方法:采用VICON (NEXUS 1.8.5)三维步态分析系统及NORAXON无线表面肌电图测试13名健康人步行过程中下肢运动学、动力学、地面反作用力以及表面肌电信号的重测信度。采用组内相关系数(ICC)及测量标准误(SEM)比较两次测试结果的相对信度与绝对信度。结果:步行过程中步速、下肢运动学、动力学、地面反作用力以及表面肌电信号均具有良好的重测信度ICC 0.78~0.96,运动学参数测量标准误SEM%为4.18~15.6,动力学参数SEM%为3.31~21.82,地面反作用力SEM%为1.70~16.67,表面肌电信号SEM%为8.00~11.11。结论:三维步态分析系统结合表面肌电图可用于评估步行时下肢运动学、动力学、地面反作用力以及表面肌电信号,且具有良好的重测信度。  相似文献   
46.
针对临床康复医师提出在下肢行走障碍患者康复训练过程中,患者身体重心缺乏在左右两脚之间的横向移动能力,从而影响行走甚至导致跌倒的问题,本文通过健康人步态行走过程的骨盆运动特征,对复杂的骨盆运动学和运动轨迹进行分析,提炼出骨盆侧向移动的轨迹和范围。根据人体工学分析,设计辅助骨盆侧向移动的机构,配合康复机器人应用在下肢行走训练,使得康复训练更接近健康人的自然状态,有利于训练过程中机械设备和人的相互作用。此方法获得医生和治疗师们的高度评价,并通过仿真试验做出了验证。  相似文献   
47.
48.

Objectives

To investigate the relation of gait training (GT) during inpatient rehabilitation (IPR) to outcomes of people with traumatic spinal cord injury (SCI).

Design

Prospective observational study using the SCIRehab database.

Setting

Six IPR facilities.

Participants

Patients with new SCI (N=1376) receiving initial rehabilitation.

Interventions

Patients were divided into groups consisting of those who did and did not receive GT. Patients were further subdivided based on their primary mode of mobility as measured by the FIM.

Main Outcome Measures

Pain rating scales, Patient Health Questionnaire Mood Subscale, Satisfaction With Life Scale, and Craig Handicap Assessment and Reporting Technique (CHART).

Results

Nearly 58% of all patients received GT, including 33.3% of patients who were primarily using a wheelchair 1 year after discharge from IPR. Those who used a wheelchair and received GT, received significantly less transfer and wheeled mobility training (P<.001). CHART physical independence (P=.002), mobility (P=.024), and occupation (P=.003) scores were significantly worse in patients who used a wheelchair at 1 year and received GT, compared with those who used a wheelchair and did not receive GT in IPR. Older age was also a significant predictor of worse participation as measured by the CHART.

Conclusions

A significant percentage of individuals who are not likely to become functional ambulators are spending portions of their IPR stays performing GT, which is associated with less time allotted for other functional interventions. GT in IPR was also associated with participation deficits at 1 year for those who used a wheelchair, implying the potential consequences of opportunity costs, pain, and psychological difficulties of receiving unsuccessful GT. Clinicians should consider these data when deciding to implement GT during initial IPR.  相似文献   
49.
通过采集腿部肌肉5个通道的肌音信号,利用3层决策树对跑步、上楼、下楼、走路、静止5种步态动作进行模式识别研究。在决策树的第1层和第2层,应用双阈值门限法识别静止和跑步两种步态模式,在第3层,提出基于步态信号的自适应不等长分割算法以及改进的模糊熵算法,利用线性分类器对走路、上楼、下楼进行分类识别。结果表明:双门限阈值法可有效地对静止和跑步进行识别,当采用改进的模糊熵特征时,对走路、上楼、下楼3种步态模式的分类准确率达到了94.87%;而当综合利用近似熵、样本熵和改进的模糊熵3种特征时,其分类准确率达到了98.76%。  相似文献   
50.
Aims: The aim of the study was to determine whether increased physical activities (PA) affect frailty for old women, 75 years and older (OO), compared to 60–74 years old (YO). Methods: This cross-sectional study measured 19 frailty indicators (muscle strength and endurance, balance, gait characteristics, and function), using 46 community-dwelling women. PA were divided into three levels by caloric expenditure per week (<2,000 kcal/week, 2,000–3,999 kcal/week, >4,000 kcal/week). Results: As PA level increased, a gap (=difference) between OO and YO narrowed for step length and function, but for quadriceps strength and endurance, a gap widened. Conclusions: Frailty progresses with aging but older women who engage in a high level of physical activity (>4,000 kcal/week) can increase mobility and functional capacity, but not for muscle strength and endurance. Starting regular resistance training activities early in the aging process is critical to improve or maintain muscle quality to offset age-related frailty.  相似文献   
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