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1.
张俊友  轩安武  阮狄克 《中国骨伤》2022,35(11):1104-1108
颈椎前路椎间盘切除融合术(anterior cervical discectomy and fusion,ACDF)应用于临床近百年,取得了良好的临床疗效,被认为是治疗颈椎病的金标准。但融合术后邻近节段退变(adjacent segment degeneration,ASDeg)受到越来越多的关注,关于其发生机制的争论主要集中在融合术导致邻近节段生物应力的改变与年龄相关的自然退变。融合术后发生ASDeg将严重影响手术的中远期疗效,部分患者甚至需要二次手术治疗。为了降低甚至避免ASDeg的发生,临床上出现许多新的技术,诸如保留运动节段的人工椎间盘置换术,新兴的细胞移植技术等,但临床疗效仍需要大量的研究进行证实。因此,发现融合术后发生ASDeg的危险因素对于临床开展融合手术具有重要的意义。目前对于ASDeg危险因素的研究仍无统一认识,本文将从颈椎前路融合术后发生ASDeg的危险因素的研究进展及相应应对措施作一综述,以指导临床实践。  相似文献   
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目的分析细棒、PEEK棒固定对寰枢关节稳定性的影响。方法采用6具新鲜成人枕骨(occipital bone,Oc)~颈椎C4节段进行测试,模拟以下手术及固定状态:①完整状态;②损伤状态:枢椎齿状突II型骨折;③坚强固定:寰枢椎均采用普通椎弓根螺钉固定,直径3.5 mm钛棒连接;④PEEK棒:直径3.5 mm的PEEK棒连接;⑤细棒:直径2.0 mm钛棒连接。采用重复测量实验设计,在完整、损伤和不同的固定状态下,通过脊柱试验机对标本分别施加1.5 N·m的前屈/后伸、左/右侧弯和左/右轴向旋转的纯力偶矩。采用Optotrak三维运动测量系统连续采集标本运动,分析寰枢椎之间角度运动范围和中性区。结果采用直径3.5 mm的钛棒,2.0 mm的细棒以及3.5 mm的PEEK棒固定后,在前屈、后伸、侧弯和旋转方向上均显著减小了固定节段的运动范围(P<0.05)。直径3.5 mm和2.0 mm的棒固定后的运动范围,在各个方向上无显著性差异。PEEK棒固定的运动范围仅在侧弯方向上大于坚强固定(P=0.005),其他方向无显著性差异。3种固定方式在屈伸、侧弯和旋转方向上均显著减小了固定节段的中性区(P<0.05)。各种固定方式之间相比较,无显著性差异(P>0.05)。结论在寰枢关节采用直径2.0 mm的细棒固定,与坚强固定的稳定性相当。采用直径3.5 mm的PEEK棒固定,在前屈、后伸、旋转方向上与坚强固定的稳定性相当,在侧弯方向上弱于坚强固定。  相似文献   
3.
BackgroundIt is unknown if improvements in gait velocity following an aerobic cycling intervention are accompanied by improved gait biomechanics in individuals with Parkinson’s disease (PD) or if gait abnormalities are exaggerated in response to increased velocity.Research questionCan an 8-week aerobic cycling intervention elicit improvements in locomotor function in individuals with mild to moderate PD?MethodsA secondary analysis of data from a randomized clinical trial was conducted in individuals with mild to moderate idiopathic PD (N = 28). Participants were randomized to an aerobic cycling intervention (PDex, N = 14) consisting of 24 sessions at a targeted aerobic intensity of 60–80% of heart rate reserve or to a no intervention control group (PDcontrol, N = 14). Change in comfortable walking speed in addition to gait kinematics, kinetics, and spatiotemporal variables using motion capture were obtained at baseline and end of treatment (EOT).ResultsThe PDex group made significantly greater improvements in the primary outcome, change in comfortable gait velocity, from 0.86 ± 0.24 m/s at baseline to 1.00 ± 0.23 m/s at EOT compared to the PDcontrol group who declined from 0.91 ± 0.23 m/s at baseline to 0.80 ± 0.29 at EOT (P = 0.002). Improvements in gait velocity for the PDex group were accompanied by improvements in gait kinematics, kinetics, and spatiotemporal parameters, while the PDcontrol group demonstrated slight worsening in all gait parameters over the 8-week period.SignificanceThe 8-week moderate- to high-intensity cycling intervention elicited significantly greater improvements in gait velocity compared to the PDcontrol group. Increased gait velocity was accompanied by normalization of gait biomechanics, rather than an exaggeration of existing gait deviations. Aerobic cycling may be a viable treatment approach to improve gait velocity and gait biomechanics in individuals with mild to moderate PD and may mitigate declines in mobility.  相似文献   
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BackgroundResearch indicates that neck kinaesthetic awareness plays an important role in oculomotor and balance control, however the relationship has not been studied in athletes. As performance in ice hockey demands visual perception acuity during skating, while constantly shifting between unilateral and bilateral stances in sports specific posture more in-depth relationship should be studied.Research questionWhat is the relationship between neck kinaesthetic awareness, postural balance and eye movement control in professional ice hockey players and non-trained individuals?MethodsIn this observational study, centre-of-pressure was measured using force plate in twenty-eight hockey players and thirty non-trained participants during different stances in eyes-opened and eyes-closed conditions. Butterfly test and Head-to-Neutral Relocation test were performed to assess neck kinaesthesia. Horizontal smooth pursuit eye movements were measured using video-oculography. Linear regression was used to determine the relationship between neck kinaesthesia, body sway and oculomotor control.ResultsTime-on-target in Butterfly test was able to predict low to medium proportions of variance in amplitude and velocity parameters for single leg stances in hockey players (R2 = .220–.698). Head-to-Neutral Relocation test was able to predict low to medium proportion of variance in average eye movement velocity during first 100 milliseconds of smooth pursuit initiation for both groups (R2 = .262–.541).SignificanceFindings from our study suggest that cervical spine afferent input plays an important role in maintaining unilateral postural balance in hockey players, with less evidence presented in controls. Sports specific posture or upper body loading could lead to adaptations in neck proprioception, not frequently considered when searching for balance related injury risk factors or performance deficits. Our study suggests, that in addition to balance control, neck kinaesthesia can also affect oculomotor performance which was present in both groups. This is especially evident when initiating changes in eye movement direction.  相似文献   
7.
ObjectivesIncreased tibial axial acceleration and reduced shock attenuation are associated with running injuries and are believed to be influenced by surface type. Trail running has increased in popularity and is thought to have softer surface properties than paved surface, but it is unclear if trail surfaces influence tibial acceleration and shock attenuation. The purpose of this study was to investigate peak triaxial and resultant tibial acceleration as well as axial and resultant shock attenuation among dirt, gravel, and paved surfaces.DesignFifteen recreational runners (12 females, 3 males, age = 27.7 ± 9.1 years) ran over dirt, gravel, and paved surfaces in a trail environment while instrumented with triaxial tibial and head accelerometers.MethodsDifferences between tri-planar peak tibial accelerations (braking, propulsion, axial, medial, lateral, and resultant) and shock attenuations (axial and resultant) among surface types were assessed with one-way ANOVAs with Bonferroni post-hoc tests.ResultsNo significant differences were found for tibial accelerations or shock attenuations among surface types (p > 0.05).ConclusionsDirt and gravel trail running surfaces do not have lower tibial accelerations or greater shock attenuation than paved surfaces. While runners are encouraged to enjoy the psychological benefits of trail running, trail surfaces do not appear to reduce loading forces associated with running-related injuries.  相似文献   
8.
ObjectiveThe lack of a PDL, which acts as an energy absorber, is a contributor to implants’ early failure; however, these discrepancies are not well understood because of limited in vivo research. This study investigated the discrepancy in biomechanical behaviors between natural teeth and dental implants by detecting micro-movements in vivo.MethodsWe designed a device that could measure precisely mechanical behaviors such as creep, stress relaxation, and hysteresis by using load–control displacement on teeth and implants. We also compared energy dissipation between natural teeth and dental implants by subtracting the area of the hysteresis loop of natural teeth from that of dental implants.ResultsBiphasic curves with an initial phase of rapid response and a subsequent phase of slow response were confirmed in creep and stress relaxation curves for the load–time relationship in natural teeth. By contrast, the behavior of creep or stress relaxation was less prominent when the dental implants were tested. We observed that the periodontal ligament under an axial intrusive load of 300 g in a loading rate 3 g/s could dissipate the energy of 7.35 ± 1.18 × 10?2 mJ, approximately 50 times that of the dental implants (1.47 ± 1.22 × 10?3) with statistically significant (p < 0.05).SignificanceWe confirmed natural teeth could achieve greater energy dissipation compared to dental implants, which owe to that natural teeth exhibited fluid and viscoelastic properties.  相似文献   
9.
Ankle sprain is very common in sports. Research on its prevention is as important as on its treatment as recommended in the 2016 consensus statement of the International Ankle Consortium. Successful prevention depends on the understanding of its mechanism, which has been presented with quantities in some recent case reports. Inciting event was suggested to be an inverted ankle joint at foot strike, however, is still lacking evidence from comparison with non-injury trials. This study investigated the ankle joint orientation at foot strike in successful non-injury cases and compared them with a previously analysed ankle sprain injury case. Two injury-free cutting motions with similar movement approach to a previously analysed ankle sprain injury performed by the same athlete were collected from an online search and were trimmed from 0.05 s before until 0.30 s after the foot strike. The video sequences were then processed by video editing software and then analysed by a model-based image-matching motion analysis technique. Ankle joint orientation at foot strike and the profiles were presented in inversion, plantarflexion and rotation planes, for both the previously analysed injury case and the two non-injury cases. The ankle joint orientation at foot strike was 0–1 degree inverted and 10–21° dorsiflexed in the two non-injury cases, compared to 14° inverted and 16° plantarflexed in the previously analysed injury case. From the case comparison, it can be observed that an inverted ankle joint orientation at foot strike in an inciting event of ankle inversion sprain.  相似文献   
10.
BackgroundSeveral clinical trials investigated the effectiveness of MT on body posture, but a systematic review grouping the results of these studies was not found in the literature.Research questionDoes manual therapy (MT) cause postural changes?MethodsInclusion criteria were: randomized controlled trials in any population; studies in which the primary intervention was the use of any MT technique; studies that evaluated the immediate, short, medium, or long-term effects of interventions on body posture; and studies published in peer-reviewed scientific journals in any year and language. In March 2022, we conducted a search in the PUBMED, Cinahl, Embase, PEDro, and Cochrane Central databases that yielded 6627 articles, of which 38 including 1597 participants were eligible; of these, 35 could be grouped into 12 meta-analyses. The risk of bias was assessed using the PEDro scale and the certainty in the scientific evidence rated through the GRADE system.ResultsThe results allowed us to conclude with moderate certainty in the evidence that, when compared to no intervention or sham, in the short and medium term, MT reduced the forward head posture (14 studies, 584 individuals, 95%CI 0.38, 1.06), reduced thoracic kyphosis (5 studies, 217 individuals, 95%CI 0.37, 0.94), improved lateral pelvic tilt (5 studies, 211 individuals, 95%CI 0.11, 0.67) and pelvic torsion (2 studies, 120 individuals, 95%CI 0.44, 1.19) and increased plantar area (3 studies, 134 individuals, 95%CI 0.04, 0.74). With moderate certainty, there was no significant effect on shoulder protrusion (5 studies, 176 individuals, 95%CI −0.11, 0.61), shoulder alignment in the frontal plane (3 studies, 160 individuals, 95%CI −0.15, 0.52), scoliosis (2 studies, 26 individuals, 95%CI −1.57, 2.19), and pelvic anteversion (5 studies, 233 individuals, 95%CI −0.02, 0.51). With low certainty, MT had no effect on scapular upward rotation (2 studies, 74 individuals, 95%CI −0.76, 2.17). With low to very low certainty, it is possible to conclude that MT was not superior to other interventions in the short or medium term regarding the improvement of forward head posture (5 studies, 170 individuals, 95%CI −1.39, 0.67) and shoulder protrusion (3 studies, 94 individuals, 95%CI −4.04, 0.97).SignificanceMT can be recommended to improve forward head posture, thoracic kyphosis and pelvic alignment in the short and medium term, but not shoulder posture and scoliosis. MT reduces the height of the plantar arch and this must be taken into account in physical therapy planning. PROSPERO registration number: CRD42021244423.  相似文献   
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