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71.
骨骼肌钝挫伤后愈合质量的肌电评价   总被引:5,自引:4,他引:1  
目的 :观察大鼠骨骼肌钝挫伤后 ,不同干预方法对骨骼肌修复过程中肌电信号的影响 ,研究肌电图在骨骼肌损伤愈合过程中的评价作用。方法 :10 8只雄性SD大鼠 ,利用自制的重物坠落打击装置造成右侧腓肠肌钝挫伤。随机分成 3组 ,即胰岛素样生长因子 - 1(IGF - 1)组、中药组和自然愈合组 ,分别于损伤局部注射IGF - 1、黄芪丹参注射液、不作处理。于伤后第 2、5、7、10、14、2 1、2 8、35、5 6天观察并比较双侧腓肠肌的肌电图变化 ,记录纤颤电位和正尖波等自发活动 ,分析复合肌肉动作电位 (CMAP)并测量其潜伏期和波幅 ,观察伤后CMAP的变化。结果 :(1)各组大鼠均于伤后第 2~ 5天出现纤颤电位和正尖波 ,约至第 7~ 10天达到高峰 ,然后逐渐减少。以IGF - 1组最早消失 ,中药组次之。 (2 )各组大鼠的伤侧肌电图CMAP中的潜伏期逐渐缩短 ,波幅逐渐增高。以IGF - 1组最快 ,中药组次之 ,自然愈合组最慢。 (3)伤后第 8周 ,IGF - 1组和中药组大鼠损伤侧CMAP波幅接近正常 ,自然愈合组则显著低于其它两组。结论 :(1)肌电图检测证实 ,IGF - 1和黄芪丹参注射液均具有促进骨骼肌损伤愈合的作用 ,但以IGF - 1的作用更明显。 (2 )损伤肌肉局部肌电信号的变化 ,可以用来评价损伤骨骼肌的修复进程和愈合质量  相似文献   
72.
目的 研究高温高湿环境下颅脑火器伤后生命体征变化特点及死亡因素。 方法 杂种猫 3 2只随机分为 4组 ,火器伤后分别放入A (2 5℃、相对湿度 50 % )、B (3 5℃、相对湿度85% )、C(3 8℃、相对湿度 90 % )、D(40℃、相对湿度 95% )四种环境中。每隔 10min记录一次血压、脉搏、呼吸频率及体温 ,到 6h时结束实验。 结果 常温枪伤组实验过程中生命体征稳定 ,随着温度及湿度的增加 ,各组动物相同时相点的体温、呼吸及心率均明显不同 (P <0 .0 5)。A组、B组动物在伤后 6h内均无死亡。C组 1.5h开始死亡 ,至 5h动物全部死亡 ,平均生存时间为 3 .4h。D组 0 .5h开始死亡 ,至 2 .5h动物全部死亡 ,平均生存时间为 2 .0h。 结论 高温高湿环境对颅脑火器伤时的生命体征变化和死亡率影响显著  相似文献   
73.
The aim of this study was to investigate the effect of a moderate soft tissue trauma to the course of fracture healing in a standardized animal model. Thirty-eight Wistar rats were randomly divided into a fracture group (F, n = 19) and a group with a fracture and a soft tissue trauma (F + STT, n = 19). The fracture and the soft tissue trauma were created using an impact device with a standardized energy. All fractures were stabilized by two Kirschner wires. Three rats were measured for blood flow and sacrificed at days 1, 3, 7, and 14, and seven rats at day 28, from both groups. A three-point bending test was performed on the healed tibia after 28 days. During the first 24 h there was a reduction in blood flow, which was more pronounced in the F + STT group than in the F group. From histological sections, the shape of the callus formation, as well as the tissue distribution of newly formed bone, fibrous cartilage and fibrous connective tissue were determined. Distinctly more periosteal new bone formed and a larger callus formed at days 3 and 7 in group F compared to group F + STT. However, by days 14 and 28, the ossification and overall callus size no longer showed differences between the two groups. A fast recovery of blood flow and callus formation took place in the F + STT group, which led to similar histological and biomechanical results in fracture healing observed after 28 days between the two groups.  相似文献   
74.
目的探讨胫腓骨交叉愈合后对踝关节运动的影响。方法回顾性分析1999年9月~2003年11月期间7例胫腓骨交叉愈合患者的临床资料。左侧4例,右侧3例。其中2例开放性骨折行钢板内固定,5例闭合性骨折行髓内钉固定。术后随访中测定踝关节的跖屈、背伸。结果7例患者获平均30个月(10~54个月)随访。参照Kofoed踝关节评分系统评价:优6例,良1例。胫腓骨交叉愈合对踝关节的背伸有6.3°左右的影响,对正常行走步态影响轻微。5例患者踝关节有不同程度不适感。结论胫腓骨交叉愈合可能对踝关节退变有重要影响,可通过术中应用合适长度的髓内钉远端锁钉、避免钻孔过深、采用微创手术及早期功能锻炼等方法来预防胫腓骨交叉愈合。  相似文献   
75.
目的研究重组人生长激素(rhGH)对腹部大手术患者术后代谢、免疫功能和术后并发症的影响。方法回顾性分析腹部大手术患者79人,其中37人为治疗组,42人为对照组。治疗组手术后第2天开始,每天皮下注射思真(重组人生长激素,瑞士雪兰诺公司生产)8U,对照组给予安慰剂(生理盐水),共用7d;分别在治疗前,治疗后3、7、10、14d检测血浆白蛋白、前白蛋白及转铁蛋白水平。记录切口愈合情况及术后并发症情况。结果(1)治疗前,两组白蛋白、前白蛋白及转铁蛋白水平差异无统计学意义(P〉0.05);治疗后3d,两组白蛋白水平差异无统计学意义(P〉0.05),且均低于治疗前;治疗组前白蛋白、转铁蛋白均高于对照组(P〈0.05);治疗后7d,治疗组3项指标均高于对照组。(2)治疗组切口愈合情况明显优于对照组(P〈0.05)。(3)治疗组术后并发症发生率明显低于对照组(P〈0.05)。结论腹部大手术患者术后应用重组人生长激素可以提高免疫功能,促进切口愈合,减少术后并发症的发生。  相似文献   
76.
Abstract Closed suction drainage systems are commonly used in orthopaedic surgery, particularly in joint arthroplasty. The rationale for the use of drains is a theoretical reduction of wound haematomas and infection. However the benefit of using drains after total hip or knee arthroplasty is controversial. Several reports have shown that the use of drains does not reduce infection and morbidity and is an unnecessary and potentially dangerous practice. In fact most studies highlighted that at best their use appears to make no difference to important clinical outcomes. Recently a metaanalysis raised the question about the usefulness of closed suction drainage again, concluding that it has no major benefits. The purpose of this study was to review the evidences available concerning the utility of closed suction drainage outlining that this practice is not supported by clinical evidence.  相似文献   
77.
Detailed data of the stability of external fixation devices are needed by the orthopaedic surgeon to predict successful healing of a fracture. The stability (rigidity, yield and failure criteria) of four half-frame configurations (single, stacked, double and delta) of the original Hoffmann and AO tubular frame have been analysed under four loading conditions: axial compression, torsion, and both AP- and ML-bending. Overall the two systems' rigidities were the same between similar configurations. Both systems' single half-frames were particularly weak; however, as the number of components (rods, pins, clamps, couplings) on the frame increased, the rigidity of the frame increased. The difference in performance between the two systems lies in their yield and failure characteristics. The AO system exhibited excellent failure criteria in all modes of loading, i.e. no configuration failed within the test limits, whereas most Hoffman frames yielded and failed at low loads.  相似文献   
78.
79.
Abstract. Effects of a topically applied growth factor combination on fibroblast migration, collagen fiber formation and bone regeneration were studied in standardized periodontal defects in 4 beagle dogs. Following elevation of facial mucoperiosteal flaps, fenestration defects, 3 mm in diameter, were made through the cortical bone and into the dentin of maxillary and mandibular teeth. Collagen sponges, impregnated with 200 ng insulin-like growth factor II, 20 ng basic fibroblast growth factor and 6 ng transforming growth factor beta 1 were fitted to defects randomly in right or left quadrants and the flaps repositioned and sutured. Contralateral control defects received the collagen with vehicle only. Experimental procedures were staggered to allow observations of healing 3, 7, 10, and 14 days after surgery. Histometric analysis showed no differences in fibroblast and collagen density between control and growth factor defects. Bone regeneration was significantly greater in control than in growth factor defects 10 and 14 days after surgery. The rate of healing generally appeared more affected by intra-dog variations or procedural variations than by the growth factor combination.  相似文献   
80.
BACKGROUND: Pemphigus vulgaris (PV) is a severe blistering disease involving the skin and mucous membranes. The most common causes of death in these patients are adverse effects of drugs, and infection. Skin lesions are one of the important sources of infection. Thus, any local treatment that could reduce healing time of lesions and consequently reduce the total dosage of drugs needed to treat is favourable. OBJECTIVE: To evaluate the efficacy of epidermal growth factor (EGF) in reducing healing time of lesions in patients with pemphigus vulgaris. METHODS: In this randomized, double-blind, within-patient, left/right, controlled trial, 20 hospitalized patients with pathologial and immunohistologial (direct and indirect immunoflourecence) proven pemphigus vulgaris (PV) were chosen. In addition, all patients had at least one appropriate pemphigus lesion on each side of the body that had not healed after 2-week systemic therapy and sterile saline washing. EGF (10 microg/g) in 0.1% silver sulfadiazine cream vs. 0.1% silver sulfadiazine cream alone was applied randomly on one side of the body. RESULTS: Kaplan-Meier survival analysis suggested that median time to heal with application of EGF plus silver sulfadiazine cream was 9 days, in comparison with 15 days for silver sulfadiazine cream alone (log-rank test, P=0.0003). No intervention-related adverse effect was observed during the study. CONCLUSIONS: EGF can significantly reduce healing time of skin lesions in patients with pemphigus vulgaris, at least when this cream base is applied (Cochrane skin group identifier: CSG20).  相似文献   
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