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81.
人工膝关节置换中的生物力学研究进展   总被引:1,自引:0,他引:1  
郭媛  史俊芬  陈维毅 《力学进展》2007,37(3):465-471
膝关节是人全身最大最复杂的关节, 它的任何一个主要组成部分的损坏都会引起膝关节的反常运动, 久之软骨和半月板发生磨损、变性而形成骨性关节病, 从而影响人的日常生活. 通常采用的方法是进行膝关节矫形或置换, 对严重病变的膝关节, 则采用全膝置换手术.随着人工膝关节置换成为非常普遍的外科手术, 与膝关节假体相关的研究也越来越多的被人所关注. 从生物力学角度对人工膝关节假体的类型和材料、假体生物力学性能的理论和实验研究、骨重建的理论模型、骨整合的理论和实验、与理论和实验相关的有限元分析模型等几个主要方面进行了详尽的综述. 同时, 指出了人工膝关节置换和目前研究中存在的问题,并对其未来的发展方向进行了一定的预测.   相似文献   
82.
目的探讨膝关节镜下手术修复和术后药物辅助治疗半月板损伤的疗效。方法对22例半月板撕裂的患者行膝关节镜下半月板修复术(其中16例从外到内缝合,6例从内到外缝合),术后给予玻璃酸钠膝关节腔内注射辅助治疗,通过二期膝关节镜和MRI检查、Lysholm膝关节功能评分对治疗效果进行评价。结果22例患者膝关节镜下半月板修复术均取得成功。二期关节镜检查5例,显示半月板愈合良好;MRI复查17例,显示半月板愈合15例,未完全愈合和未愈合各1例;术后Lysholm平均评分较术前明显提高,差异具有统计学意义(P<0.01);疗效优14例,良6例,可1例,差1例,优良率90.9%(20/22)。结论膝关节镜下半月板修复术结合玻璃酸钠膝关节腔内注射治疗半月板损伤可取得良好的疗效。  相似文献   
83.
Objective: To compare the effect of body-weight-supported treadmill training (BWSTT) and full-body-weight treadmill training (FBWTT) on patients with knee osteoarthritis (OA). Methods: Design was Randomized controlled trial. Patients with knee osteoarthritis (n = 30; mean age, 76.0±7.5 y) were randomly assigned to BWSTT or FBWTT group. All patients performed 20 min walking exercise twice a week for 6 weeks under the supervision of the therapist. Main measures were 10-meter walking test (10MWT), functional reach test (FRT), timed get up and go test (TUG), one-leg standing test, 6-minute walking test (6MWT), the parameters set on the treadmill, MOS Short-Form 36-Item Health Survey (SF36), Japanese Knee Osteoarthritis Measure (JKOM). Results: Twenty-five patients (10 men, 15 women; mean age, 76.5 ± 8.0 y) completed the experiment. Exercise capacity, indicated by the heart rate, was similar in both groups. After 3 weeks of BWSTT, the patients performed significantly better in the 10-m and 6-min walking tests. This was not the case with FBWTT even after 6 weeks training. Pain levels assessed were significantly improved after 3 weeks of BWSTT and 6 weeks of FBWTT. There were no significant improvements in either group assessed by the FRT, one-leg standing time test, TUG, or SF -36 questionnaire. Conclusions: BWSTT enhanced exercise capacity in terms of walking speed and pain reduction after 3 weeks; however, there was no significant improvement in patients'' functional abilities or quality of life.  相似文献   
84.
The stability and in vivo robustness of [177Lu]Lu–DOTP as a potential bone-targeting radiopharmaceutical was determined with the aid of thermodynamic blood plasma modeling simulations. Glass electrode potentiometry was employed to measure the stability constants of the complexes of Lu3+ with DOTP. Similarly, the complexes of DOTP with a selection of the important physiological metal ions: Ca2+, Mg2+, and Cu2+ were determined, representing the typical interactions that the ligand would encounter upon administration. This made possible the construction of a blood plasma model of DOTP, aiding in establishing the potential susceptibility of the radiopharmaceutical. The ligand binds predominantly to calcium in vivo, accounting for 59.6% of that initially introduced as a component of the Lu–DOTP complex. Furthermore, due to a preference of the DOTP to bind to Cu2+ it causes mobilization of the ions in blood plasma, and would therefore indicate a deficiency if the ligand is administered at a concentration of 8.5 × 10−5 mol dm−3. The lutetium-ions are preferentially bound to DOTP, with as much as 98.1% of the Lu3+ occupying the ligand under physiological conditions.  相似文献   
85.
采用牛关节软骨与不锈钢摩擦副在人工膝关节模拟运动试验机上进行模拟膝关节运动的摩擦学试验研究,探讨载荷和时间对摩擦磨损行为的影响并分析其作用机理,同时对软骨表面进行分析。结果表明:随着载荷从640增至1000 N,牛软骨表面磨痕的宽度的深度均增大;在同样载荷下,随着模拟运动时间从20增至60 min,牛软骨表面磨痕的宽度和深度增大。软骨磨损表面的磨痕和破损表面检测有铁元素的存在,表明不锈钢材料在摩擦过程中发生转移。试验后得到的磨粒包括长条形的金属磨粒和圆形的软骨成分磨粒。  相似文献   
86.
87.
The paper investigates the overall and detailed features of cosmic ray(CR) spectra in the knee region using the scenario of nuclei-photon interactions around the acceleration sources.Young supernova remnants can be the physical realities of such kind of CR acceleration sites.The results show that the model can well explain the following problems simultaneously with one set of source parameters:the knee of CR spectra and the sharpness of the knee,the detailed irregular structures of CR spectra,the so-calledc...  相似文献   
88.
The aim of this study was to compare the effectiveness of extracorporeal shock wave therapy (ESWT) and ultrasound therapy (US) for managing heel pain. Thirty-seven subjects received either: ESWT (once a week), US (three times a week), or CONTROL (no treatment) for 3 consecutive weeks and were followed-up for 3 more weeks. A visual analogue scale (VAS), the maximum tolerable duration for prolonged walking or standing, and the Mayo clinical scoring system (MCSS) were evaluated. Mixed models treating baseline measures as covariates were adopted for statistical analysis. By week 3, intensity of heel pain on palpation was reduced by 37% (VAS score from 7.5 to 4.6) in the ESWT group, 24% (from 5.3 to 4.2) in the US group, and increased by 3% (5.6–5.7) in the control group; this difference was significant after adjusting for baseline VAS scores (p = 0.022). The improvements in the maximum tolerable duration of prolonged walking or standing was only significant in the ESWT group (157% increase, p = 0.043) but not the other two groups. Both active treatment groups maintained the treatment effect at the three-week follow-up. We conclude that ESWT is potentially more effective in reducing heel pain than ultrasound therapy but additional evidence is needed due to the various limitations of the study.   相似文献   
89.
潘洁  杨海峰  胡志英 《应用数学》2015,37(4):330-332
目的 探讨IIIB 型前列腺炎患者抑郁水平和社会支持的相关性。方法 采用抑郁自评量表(SDS)和社会支持评定量表(SSRS)对48 例IIIB 型前列腺炎患者进行测评,抑郁和社会支持的相关性采用Spearman 相关性分析。结果 IIIB 型前列腺炎患者的抑郁发生率和SDS 评分明显高于对照组,差异有统计学意义(P<0.01);Spearman 相关性分析表明,抑郁程度与社会支持总和、主观支持、客观支持和支持利用呈显著负相关(均P<0.05)。结论 大部分IIIB型前列腺炎患者存在抑郁情绪,其发生可能与社会支持程度较低有关;减轻IIIB 型前列腺炎患者的抑郁情绪可通过重视社会支持和加强护理干预来进行。  相似文献   
90.
THE ROLE OF FRONTAL NEURONS IN PAIN AND ACUPUNCTURE ANALGESIA   总被引:1,自引:0,他引:1  
To study the role of frontal neurons in pain and acupuncture analgesia, experiments were carried out on 4 monkeys (Macaca mulatta) during performing two tasks, the Heat Discrimination Response GO/NO-GO Task (Task Ⅰ) and the Heat Delayed Discrimination GO/NO-GO Task (Task Ⅱ). After a criterion of 90% of correct performances over three successive days had been reached, activity of single neurons was recorded from the frontal cortex. Of 276 Task Ⅰ-related neurons, 211 responded to noxious and/or innocuous heat stimuli. Of 73 Task Ⅱ-related neurons, 59 responded to noxious and/or innocuous heat stimuli. During acupuncture, the nociceptive reaction time for lever release to avoid painful stimuli was increased, the percentage of correct performances was lowered, and the neuronal responses to noxious and/or innocuous stimuli were suppressed. These neurons were mainly located in a circumscribed area medial to the superior ramus of the arcuate sulcus in frontal cortex, including the prefrontal and premotor a  相似文献   
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