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81.
目的 观察并探讨pcD2/hVEGF对缺血皮瓣血循环重建和皮瓣存活率的影响.方法 SD大鼠24只,分2组,每组12只.在鼠背部制作蒂位于尾侧的缺血皮瓣(7cm×1cm).实验组皮下注射pcD2/hVEGF,对照组皮下注射生理盐水,术后7天观察皮瓣存活面积比、单位面积微血管计数和及VEGF基因表达水平.结果 2组中pcD2VEGF组皮瓣存活面积比、单位面积微血管密度与对照组有显著性差异.结论 pcD2VEGF能促进缺血皮瓣存活.  相似文献   
82.
The cosmetic result, cost effectiveness, and complication rate of three different types of skin closure: staples, tapes, and interrupted nylon were compared. In 68 wounds, skin closure was randomized to staples, tapes, or interrupted 3/0 nylon sutures. All wounds were closed subcutaneously with interrupted undyed 2/0 dexon. For 3 months, 59 wounds were followed and assessed by an independent observer at 1 and 3 months postopera-tively in the outpatient department. In three different skin closures, the cosmetic result was superior for tapes because the wound line itself was finer and there were no dot scars. Tapes were the most cost-effective because they are the cheapest although they were not as quick to apply as staples. There was no difference in complication rate. Tapes also afforded the greatest patient comfort.  相似文献   
83.
Background The skin microdiallysis technique makes it possible to measure histamine release in intact human skin in vivo directly. In this study we have used the microdialysis technique to characterize histamine release by codeine after intracutaneous injectioin and following skin challenge by a novel atraumatic delivery technique. Objective The purpose of the study was to compare histamine release in human skin by codeine. delivered by an intraprobe drug delivery system (IPD) and intracutaneous injections (ICT), with respect to dose-response relations, kinetics of histamine appearance and decay, corelations between histamine release and skin respones, and reproducibility. Methods Hollow dialysis fibres were inserted intradermally in 12 healthy subjects. Twelve fibres were inserted in each subjects, six fibres in each arm. Each fibre was perfused at a rate of 3 μL/min, and samples were collected in 2 min fractions. By the IPD technique, codeine was administrered to the skin by adding codeine to the perfusion medium. Sequential IPD challenges were performed in one arm. and ICTs were done on the other arm. Results Sixfold serial dilutions of codeine (0.01-3 mg/mL) caused a significant doserelated histamine release by ICT and IPD. Peak histamine release was found within the first 4 min after skin challenge by ICT and IPD, followed by a fast decline with a dialysate histamine half life of approximately 2-3 min. Peak hisamine release was linearly correlates with cumulative release of the 20 min sampling period, and histamine release correlated with weal soze. The coefficient of variation on peak histamine releae was 18.9% and 4.8% for codeine ICT and IPD, respectively. Conclusioin We have described in detail codeine-induced histamine release in intact human skin in vivo by the microdialysis technique. It was possible to administer codeine atraumaticallyl to the skin by intraprobe delivery. The skin microdialysis codeine atraumaticallly to the skin by intraprobe delivery. The skin microdialysis technique opens up possibilities for measurement of infllammatory mediators release in normal and diseases skin, and it will be possible to deliver immunopharmacologically active drugsto the skin by intraprobe delivery.  相似文献   
84.
Tests of autonomic dysfunction in patients with multiple sclerosis   总被引:2,自引:0,他引:2  
Autonomic dysfunction is frequent in patients with multiple sclerosis (MS). The sympathetic skin response (SSR) and the R-R interval variation (RRIV) are simple electrophysiologic tests for the assessment of central and peripheral autonomic disturbances. Both tests were performed in 60 patients with clinically definite MS and 30 controls. The SSR was recorded simultaneously from both upper and both lower limbs. In all volunteers normal responses were recorded from the four limbs, but 39 patients (65%) showed abnormal responses in at least one limb. The reduction in amplitude of the response was correlated with patients' EDSS. In individual limbs, the SSR amplitude correlated with weakness, spasticity and cerebellar dysfunction, but was not sufficiently related to the deep sensory loss. The RRIV was abnormal in 48 MS patients (80%), as compared to the controls, but showed no significant relationship either to the EDSS or to the SSR. The sensitivity of SSR and RRIV is high and comparable with that of visual and somatosensory evoked potentials.  相似文献   
85.
应用全厚皮片移植修复治疗183例颈部烧伤后瘢痕挛缩畸形患者,术后经3~5年随访观察效果确切.并对全厚皮片术后易发生收缩的问题,进行讨论.  相似文献   
86.
总结胸腹轴型皮瓣早期修复上肢不同部位的深度蛇伤溃疡的经验,评价其应用价值。本组16例,胸脐皮瓣2例,侧胸腹皮瓣1例,髂腰皮瓣5例,下腹皮瓣6例,下腹分叶皮瓣1例,髂腰加下腹Y形皮瓣1例。术后1例皮瓣远端坏死,3例轻度感染,16例断蒂后全部成活。随访3个月~7年,皮瓣质地和弹性均好,手功能基本恢复。认为,带蒂胸腹轴型皮瓣是修复上肢深度蛇伤溃疡理想的方法。  相似文献   
87.
Summary Thermoregulatory sweating [total body (m sw,b), chest (m sw,c) and thigh (m sw,t) sweating], body temperatures [oesophageal (T oes) and mean skin temperature (T sk)] and heart rate were investigated in five sleep-deprived subjects (kept awake for 27 h) while exercising on a cycle (45 min at approximately 50% maximal oxygen consumption) in moderate heat (T air andT wall at 35° C. Them sw,c andm sw,t were measured under local thermal clamp (T sk,1), set at 35.5° C. After sleep deprivation, neither the levels of body temperatures (T oes,T sk) nor the levels ofm sw, b,m sw, c orm sw, t differed from control at rest or during exercise steady state. During the transient phase of exercise (whenT sk andT sk,1 were unvarying), them sw, c andm sw, t changes were positively correlated with those ofT oes. The slopes of them sw, c versusT oes, orm sw, t versusT oes relationships remained unchanged between control and sleep-loss experiments. Thus the slopes of the local sweating versusT oes, relationships (m sw, c andm sw, t sweating data pooled which reached 1.05 (SEM 0.14) mg·cm–2·min–1°C–1 and 1.14 (SEM 0.18) mg·cm–2·min–1·°C–1 before and after sleep deprivation) respectively did not differ. However, in our experiment, sleep deprivation significantly increased theT oes threshold for the onset of bothm sw, c andm sw, t (+0.3° C,P<0.001). From our investigations it would seem that the delayed core temperature for sweating onset in sleep-deprived humans, while exercising moderately in the heat, is likely to have been due to alterations occurring at the central level.  相似文献   
88.
1. Age-related changes in prejunctional alpha 2-adrenoceptors were examined in the rat vas deferens using pharmacological techniques. 2. B-HT 933 (1 x 10(-8) - 1 x 10(-6) mol/L) caused a concentration-dependent inhibition of isometric contractions (tetrodotoxin-sensitive) induced by stimulation with single field-stimulus pulses, in both the epididymal and prostatic regions of rat vas deferens. The concentration-response curve to B-HT 933 was shifted to the right with age in the prostatic regions of the vas deferens. 3. In high concentrations (10(-6) - 3 x 10(-4) mol/L), B-HT 933 caused concentration-dependent enhancement of the contractile response to stimulation and evoked spontaneous contractile activity. No significant difference in this postjunctional activity occurred with age in either the prostatic or epididymal regions of the vas deferens. 4. Schild analysis revealed no significant differences in pA2 values for the antagonisms of the prejunctional inhibitory effect of B-HT 933 by rauwolscine in either the prostatic or epididymal regions of vas deferens between young and old rats. 5. These results could be interpreted as a decrease in alpha 2-adrenoceptor number with age. The more marked decrease in the prejunctional inhibitor potency of B-HT 933 in prostatic regions of vas deferens with aging may be due to a smaller receptor reserve in this region of the vas deferens.  相似文献   
89.
真皮下血管网岛状皮瓣抗菌力的实验研究   总被引:2,自引:0,他引:2  
为研究真皮下血管网薄皮瓣用于感染创面的可行性,在家猪臀部两侧分别形成以旋髂深血管主干分支为蒂的传统岛状皮瓣和远侧50%修薄的真皮下血管网岛状皮瓣。用细菌计数、吖啶橙荧光染色测定白细胞吞噬指数和白细胞内杀菌率,应用激光多普勒、墨汁灌注、透明标本等方法,对两种皮瓣的抗菌力作自身对照研究。结果表明,真皮下血管网岛状皮瓣的抗菌力明显降低,可能与皮瓣修薄后血供减少,白细胞功能相应降低有关。  相似文献   
90.
地塞米松在大鼠缺血随意皮瓣中的作用   总被引:2,自引:0,他引:2  
目的:研究局部使用地塞米松对大鼠缺血随意皮瓣的作用。方法:建立大鼠背部缺血随意皮瓣的动物模型,随机分为2组,实验组术后皮瓣下一次给予地塞米松5mg(用生理盐水稀释至3ml),对照组术后皮瓣下一次给予0.9%生理盐水3ml。均于术后7d取材,测定皮瓣坏死率和组织中丙二醛含量,观察大体及病理切片。结果:实验组皮瓣坏死率和丙二醛含量较对照组显著降低(P<0.01)。光镜下,实验组的炎性反应较对照组明显减轻。结论:地塞米松能提高缺血随意皮瓣的成活率,大剂量一次性给药的方法是可行的。  相似文献   
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