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21.
王涛  邱秀翠  焦艳艳  刘辉  刘永杰 《昆虫学报》2012,55(11):1239-1245
双酰基肼类杀虫剂模拟天然蜕皮激素作用影响幼虫蜕皮。昆虫蜕皮激素受体的高度敏感性和专一性要求必须建立新的杀虫活性检测技术, 以适应快速准确和大批量筛选的要求。本研究采用RT-PCR技术, 获取斜纹夜蛾Spodoptera litura蜕皮激素受体(EcR)与超气门蛋白(USP)功能域目的基因, 构建EcR、 USP功能区基因原核表达载体(pEHISEGFPTEV-EcRcde和pEHISEGFPTEV-USPcde)。载体经诱导表达和蛋白纯化, 获得EcR和USP功能区纯化蛋白。在蛋白浓度l mg/mL, 3H-PonA终浓度8 nmol/L的条件下, 采用放射性配基受体结合分析测定了4种药剂(虫酰肼、 呋喃虫酰肼、 抑食肼和灭幼脲)不同浓度下的放射性比活的变化。结果显示: 随着药剂浓度的逐渐增大, 前3种药剂的放射性比活都有不同程度的降低, 其中虫酰肼的放射性比活降低程度最大, 其次是呋喃虫酰肼和抑食肼, 灭幼脲的放射性比活基本无变化。这些结果表明相同条件下虫酰肼比呋喃虫酰肼和抑食肼有更高的杀虫活力, 本研究的方法可对双酰基肼类杀虫剂或者先导化合物进行初步筛选。  相似文献   
22.
Bradykinin-related peptides, kinins, ubiquitously occur in the nervous system and together with other pro-inflammatory mediators contribute to pathological states of that tissue such as edema and chronic pain. In the current work we characterized the kinin-forming system of neuronal cells obtained by differentiation of human neuroblastoma cell line IMR-32 with retinoic acid. These cells were shown to concentrate exogenous kinin precursors, kininogens, on the surface, release kinins from kininogens and subsequently convert kinins to their des-Arg metabolites. Significantly higher amounts of kinins and des-Arg-kinins were produced after cell stimulation with interferon-γ, a potent pro-inflammatory mediator involved in many neurological disorders. The expression of the major tissue kininogenase (the human kallikrein 1) and the major cell membrane-bound kininase (the carboxypeptidase M) also increased after cell stimulation with interferon-γ, suggesting the involvement of these enzymes in the kinin production and degradation, respectively. Interferon-γ was also able to up-regulate the expression of two known subtypes of kinin receptors. On the protein level, the changes were only observed in the expression of the des-Arg-kinin-specific type 1 receptor which functions in the propagation of the inflammatory state. Taken together, these results suggest a novel way for local kinin and des-Arg-kinin generation in the nervous tissue during pathological states accompanied by interferon-γ release.  相似文献   
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24.
The aim of this study was to compare muscle force control and proprioception between conventional and new-generation experimental orthoses. Sixteen healthy subjects participated in a single-blind controlled trial in which two different types of orthosis were applied to the dominant knee or ankle, while the following variables were evaluated: muscle force control (accuracy), joint position sense, kinesthesia, static balance as well as subjective outcomes. The use of experimental orthoses resulted in better force accuracy during isometric knee extensions compared to conventional orthoses (P = 0.005). Moreover, the use of experimental orthoses resulted in better force accuracy during concentric (P = 0.010) and eccentric (P = 0.014) ankle plantar flexions and better knee joint kinesthesia in the flexed position (P = 0.004) compared to conventional orthoses. Subjective comfort (P < 0.001) and preference scores were higher with experimental orthoses compared to conventional ones. In conclusion, orthosis type affected static and dynamic muscle force control, kinesthesia, and perceived comfort in healthy subjects. New-generation experimental knee and ankle orthoses may thus be recommended for prophylactic joint bracing during physical activity and to improve the compliance for orthosis use, particularly in patients who require long-term bracing.  相似文献   
25.
Investigate reflex responses in muscles throughout the lower limb and low back during sudden inversion perturbations in individuals with and without Functional Ankle Instability (FAI) while walking. Forty subjects participated in the study. Surface electromyogram recordings were obtained from the fibularis (FIB), gluteus medius (GM), erector spinae (ES), and sternocleidomastoid (SCM) of the injured/matched side as well as the uninjured/matched contralateral side (FIB_CLS, GM_CLS, or ES_CLS). Latency and amplitude data were collected while subjects were walking on a custom-built perturbation walkway. The onset of the short-latency stretch reflex of the FIB was significantly later in the injured side of the FAI individuals when compared to the control group (P = 0.009). Both the short and long latency reflex amplitude was significantly smaller in the FIB muscle in the FAI group than in the control group (P < 0.008). No significant differences in latency or amplitude reflex responses were identified between the two groups in the GM, ES, FIB_CLS, GM_CLS, or ES_CLS (P > .05). Interpretation of these results indicate that during a dynamic perturbation task individuals with FAI demonstrate longer fibularis muscle latencies on the injured side while no significant changes in the proximal muscle groups. Additionally, short and long latency reflex amplitude was significantly decreased in FAI individuals.  相似文献   
26.
A parametric model was developed to describe the relationship between muscle moment arm and joint angle. The model was applied to the dorsiflexor muscle group in mice, for which the moment arm was determined as a function of ankle angle. The moment arm was calculated from the torque measured about the ankle upon application of a known force along the line of action of the dorsiflexor muscle group. The dependence of the dorsiflexor moment arm on ankle angle was modeled as r=R sin(a+Δ), where r is the moment arm calculated from the measured torque and a is the joint angle. A least-squares curve fit yielded values for R, the maximum moment arm, and Δ, the angle at which the maximum moment arm occurs as offset from 90°. Parametric models were developed for two strains of mice, and no differences were found between the moment arms determined for each strain. Values for the maximum moment arm, R, for the two different strains were 0.99 and 1.14 mm, in agreement with the limited data available from the literature. While in some cases moment arm data may be better fitted by a polynomial, use of the parametric model provides a moment arm relationship with meaningful anatomical constants, allowing for the direct comparison of moment arm characteristics between different strains and species.  相似文献   
27.
目的:探讨矫形鞋垫联合踝关节持续被动运动(CPM)用于偏瘫型脑瘫患儿姿势控制的临床价值。方法:选择2016年6月~2017年6月在我院康复科就诊的56例偏瘫型脑瘫患儿,随机均分成两组。对照组患儿每日行物理治疗(PT)训练,每次共30分钟,每日一次,每周五次。治疗组患儿常规物理治疗训练同对照组,并同时运用足部生物力学矫形技术及踝关节CPM治疗,每次15分钟,角度恒定为-45-45度,每天一次。两组治疗疗程为三个月。治疗结束后,比较两组患儿的儿平衡能力总有效率、GMFM(E功能区评分)、肢体运动功能、踝关节张力及踝关节活动范围的改善情况。结果:两组患儿平衡能力总有效率(显效率与有效率之和)分别为92.9%和67.9%,治疗组明显优于对照组(P0.05)。治疗组治疗后GMFM(E功能区评分比较)明显高于对照组(P0.01),患侧肢体运动功能改善、踝关节张力、踝关节活动范围改善情况均明显优于对照组(P0.05)。结论:矫形鞋垫联合踝关节CPM明显有助于偏瘫型脑瘫患儿姿势控制的治疗。  相似文献   
28.
目的:比较后踝骨折两种不同类型的临床区别,为后踝骨折的临床诊治提供借鉴参考依据。方法:选取2010年1月-2013年1月我院收治的成人胫腓骨骨干骨折和单纯踝关节骨折患者3578例为研究对象,对两种骨折患者的后踝骨折发生率、后踝骨折合并外踝骨折的发生率等进行比较分析。结果:(1)TAF患者的后踝骨折发生率高于单纯踝关节骨折患者的后踝骨折发生率,差异具有统计学意义(P0.05);(2)TSPMF患者的外踝骨折发生率低于单纯后踝关节骨折的外踝骨折发生率,差异具有统计学意义(P0.05)。结论:胫骨螺旋形骨折与单纯踝关节骨折存在一定程度的差异,临床实践中应针对两种骨折的临床特点实施有针对性的治疗方案。  相似文献   
29.
Kinematics and flexibility properties of both natural and replaced ankle joints are affected by the geometry of the articulating surfaces. Recent studies proposed an original saddle-shaped, skewed, truncated cone with laterally oriented apex, as tibiotalar contact surfaces for ankle prosthesis. The goal of this study was to compare in vitro this novel design with traditional cylindrical or medially centered conic geometries in terms of their ability to replicate the natural ankle joint mechanics. Ten lower limb cadaver specimens underwent a validated process of custom design for the replacement of the natural ankle joint. The process included medical imaging, 3D modeling and printing of implantable sets of artificial articular surfaces based on these three geometries. Kinematics and flexibility of the overall ankle complex, along with the separate ankle and subtalar joints, were measured under cyclic loading. In the neutral and in maximum plantarflexion positions, the range of motion under torques in the three anatomical planes of the three custom artificial surfaces was not significantly different from that of the natural surfaces. In maximum dorsiflexion the difference was significant for all three artificial surfaces at the ankle complex, and only for the cylindrical and medially centered conic geometries at the tibiotalar joint. Natural joint flexibility was restored by the artificial surfaces nearly in all positions. The present study provides experimental support for designing articular surfaces matching the specific morphology of the ankle to be replace, and lays the foundations of the overall process for designing and manufacturing patient-specific total ankle replacements.  相似文献   
30.
摘要 目的:对比后外侧与后内侧入路内固定术治疗旋后外旋型Ⅳ度踝关节骨折治疗效果。方法:回顾性分析2019年5月-2021年5月于本院治疗的89例旋后外旋型Ⅳ度踝关节骨折患者的临床资料,按照钢板螺钉内固定术入路不同手术入路分组,其中41例手术入路为后内侧入路(对照组),48例手术入路为后外侧入路(观察组)。对照组中男24例,女17例,年龄23~65岁,平均(39.88±9.36)岁;患侧:左侧23例,右侧18例,受伤原因:交通事故26例,高处坠落15例。观察组中男27例,女21例,年龄22~67岁,平均(41.47±9.27)岁,患侧:左侧28例,右侧20例,受伤原因:交通事故32例,高处坠落16例。对比术后6个月两组骨折愈合情况、手术指标、踝关节功能、生活质量以及并发症情况。结果:观察组骨折愈合优良率为95.83%,明显高于对照组80.49%(P<0.05);与对照组比较,观察组术中出血量较少,手术时间、骨折愈合时间及住院时间均较短(P<0.05);术前两组踝关节功能及健康状况调查简表(SF-36)无差异(P>0.05),术后踝关节功能、生活质量均提高,而观察组术后踝-后足功能、Mazur(踝关节症状和功能)评分、SF-36评分均高于对照组(P<0.05);观察组并发症总发生率为4.16%,明显低于对照组17.07%(P<0.05)。结论:后外侧入路较后内侧入路钢板螺钉内固定术治疗旋后外旋型Ⅳ度踝关节骨折的疗效更佳,可提高骨折愈合率、踝关节功能和生活质量,并有助于降低术后并发症发生率。  相似文献   
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