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1.
本研究初步评价CHIMEHERB人工皮的治疗效果.74例,105个创面应用人工皮:供皮区47个创面,愈合时间平均为9±1.94d(天),油纱布对照为11.7±1.93d(P<0.01);14个浅Ⅱ°新鲜创面,70%在3~5d内逐渐干燥与创面紧密粘附,平均愈合时间为9.8±3.09d;11个存留上皮组织的削痂深Ⅱ°创面,平均5.7±1.7d干燥,平均愈合时间为10.55±3.09d,不需植自体皮;8个削痂刨面至脂肪组织或切痂创面4~9d更植自体皮,其存活率近乎100%,2个创面因残留坏死组织而失败;人工皮应用于16个自体皮间隙创面,除三个网状植皮和一个条状植皮创面失败外,所植自体皮都在人工皮下扩展融合,未观察到占位现象;对后期残余小创面有良好的效果.本研究结果提示人工皮对创面愈合具有有利影响.主要适用于供皮区、浅Ⅱ°新鲜创面、深Ⅱ°脱痂和削痂后存留上皮组织较多的创面、自体皮间隙创面和后期残余小创面,不适宜于深Ⅲ°新鲜创面.  相似文献   
2.
从1989年4月~1990年10月,我科在69例病人中使用CHIMEHERB人工皮,覆盖治疗了供皮区,Ⅱ°烧伤创面、脱痂创面的残余肉芽创面.临床应用表明:CHIMEHERB人工皮能加快创面的愈合,是目前较好的一种创面覆盖物,用人工皮覆盖创面2~3天后,人工皮干燥,不需再换药,可减轻病人的痛苦.  相似文献   
3.
The North Anatolian fault zone that ruptured during the mainshock of theM 7.4 Kocaeli (Izmit) earthquake of 17 August 1999 has beenmonitored using S wave splitting, in order to test a hypothesisproposed by Tadokoro et al. (1999). This idea is based on the observationof the M 7.2 1995 Hyogo-ken Nanbu (Kobe) earthquake, Japan.After the Hyogo-ken Nanbu earthquake, a temporal change was detectedin the direction of faster shear wave polarization in 2–3 years after the mainshock (Tadokoro, 1999). Four seismic stations were installed within andnear the fault zone at Kizanlik where the fault offset was 1.5 m, about80 km to the east of the epicenter of the Kocaeli earthquake. Theobservation period was from August 30 to October 27, 1999. Preliminaryresult shows that the average directions of faster shear wave polarization attwo stations were roughly parallel to the fault strike. We expect that thedirection of faster shear wave polarization will change to the same directionas the regional tectonic stress reflecting fault healing process. We havealready carried out a repeated aftershock observation at the same site in2000 for monitoring the fault healing process.  相似文献   
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5.
目的 探究持续封闭负压引流技术(VSD)对瘢痕切除创面成纤维细胞生长环境的影响。方法 回顾性分析2014年1月~2015年11月于笔者医院行植皮手术的四肢瘢痕切除术后患者60例,根据植皮手术前是否接受VSD治疗分为负压组(n=30)和包扎组(n=30),负压组均于一期植皮前接受VSD治疗,包扎组未接受VSD治疗。回顾性分析对比两组患者并发症发生率、首次植皮存活率、创面感染率、住院时间之间的差异。并用TUNEL染色、CD34染色法对比瘢痕标本中成纤维细胞凋亡指数及血管生成情况。结果 负压组菌培养阳性率明显低于包扎组(P<0.05),植皮存活率明显高于包扎组(P<0.05)。两组并发症发生率、住院时间、疼痛评分、随访VSS评分间比较,负压组均明显较低(P<0.05)。负压组成纤维细胞凋亡指数明显较低,微血管计数明显较高(P<0.05)。结论 负压封闭引流可以减轻瘢痕切除创面感染率,有效减轻炎性水肿,且可以通过改变局部血液循环微环境以及机械应力作用促进成纤维细胞增殖分裂,提高创面恢复效果。  相似文献   
6.
ZHANG Shu  HE Chang-rong 《地震地质》2019,41(4):1012-1026
To understand the mechanism of lower-crust earthquake and slow slips, it is necessary to study the frictional properties of mafic rocks and their major rock-forming minerals. Previous studies have performed a series of experimental researches on gabbro, basalt and their major constituents. According to the results of previous experiments, frictional sliding of plagioclase under hydrothermal conditions(100~600℃)shows a property of velocity weakening, and the experimental results show that both the direct rate effect parameter(a)and the healing effect parameter(b)increase with temperature, a typical feature for thermally-activated processes. Velocity weakening means property of a shear band that has a stronger friction healing effect than the direct rate effect in the rate and state friction constitutive framework, and the healing effect(b value)in constitutive relation mainly reflects the increase in contact area with time under hydrothermal conditions, with some minor effect of structural changes. Since the microphysical mechanism of feldspar minerals at the contacts is mainly brittle cataclasis for temperatures below 600℃, the significant frictional healing effect in this case can only be explained by the mechanism of pressure solution. In order to determine if the dissolution process of plagioclase actually occurs on the laboratory time scale, we conducted hydrostatic experiments on plagioclase powder samples under hydrothermal conditions whereby frequent contact switch between particles seen in frictional sliding experiments can be avoided, making the observation on the dissolution sites possible. Experimental temperatures were 400℃ and 500℃, with confining pressure of 90~150MPa, pore pressure of 30MPa, with 2mm initial thickness of fault gouge. The mechanical data show that a creep process occurred in the plagioclase fault gouge in the experimental temperature and pressure range; and the microstructures of the experiment show that precipitation of new grains is prevalent as the product of pressure solution process between plagioclase particles. At the same time, it is observed that the contact points have an appearance similar to fused, fuzzy structure as signatures of dissolution. The results of our experiments provide a definite experimental evidence for the healing mechanism in friction of plagioclase and for the theoretical relation between unstable slip and the pressure solution process. The results of the experiments are summarized as follows: (1)Drainage rate of pore water in plagioclase gouge was high in the first few hours of experiment, but gradually decreases over time for both temperature and pressure series of experiments slowing down to a steady state. This feature indicates that there is a creep process that evolves inside the plagioclase gouge. In the temperature-series experiments, the drainage rate of the pore water in the plagioclase gouge at 400℃ is relatively low than the cases for higher temperatures. Thus, the applied temperature is positively correlated with the creep of plagioclase gouge. (2)Scanning electron microscopy(SEM)observations of the experimentally deformed samples were performed on thin sections cut along the sample axis. Firstly, from the images of microstructure, it was found that the degree of particle fracture became more significant at a higher effective pressure, with smaller pore volume between particles. In the temperature-series experiments it was found that the degree of compaction of plagioclase gouge increased with increasing temperature. Precipitation of plagioclase grains in layered structures was generally observed in high-magnification images, indicating the presence of pressure solution processes. Contact points were also found to be in a state of ambiguity that seems to be a fused morphology, but the details of the structure remain to be determined by further observations. The above results indicate that the pressure solution process of plagioclase particles can occur on a typical laboratory time scale, and the results of this study provide robust experimental evidences for the theory that links between pressure solution and the mechanism of frictional healing and unstable slips for plagioclase.  相似文献   
7.
1989年4月~1990年10月期间,由全国组成的临床研究组10个烧伤单位对CHIMEHERB人工皮进行全面临床研究.研究目的是:(1)探索应用方法.(2)明确适应症.(3)评价疗效.在260例烧伤病人中,共应用365个不同类型创面,有效率为90.5%,其中优良率为79.7%.研究指出,CHIMEHERB人工皮的性能适合于作为暂时性创面覆盖物,对上皮生长具有有利影响,未发现占位和排斥现象,以及过敏和其他不良反应.主要适用于(1)供皮区,(2)Ⅱ°烧伤创面.(3)深Ⅲ°烧伤脱痂和削痂创面.(4)网状植皮和小皮片(或条状)植皮创面。(5)残余肉芽创面.亦可用于切痂创面.但不适于深Ⅱ°新鲜创面和切痂嵌皮.感染创面应用CHIMEHERB人工皮应结合抗感染措施.应用人工皮创面需良好包扎与固定.人工皮下渗出物多需引流.  相似文献   
8.
16例烧伤病人应用CHIMEHERB人工皮覆盖26个创面,其中浅Ⅱ°及部分深Ⅱ°创面11个,深Ⅲ°削痂创面10个,切削痂覆盖自体网状皮创面5个,与辐照猪皮对照观察,临床获得较好效果.认为在有效的清创及正确的创面处理下覆盖人工皮能减少创面渗出,有利创面愈合.作为一种新型的生物性敷料,无同种异体皮或异种皮移植时的排异现象,但其本身不具抗菌能力.  相似文献   
9.
在皮肤微粒播散移植中应用CHIMEHERB人工皮覆盖6例,8个部位取得了较满意的效果,显示CHIMEHERB人工皮覆盖部位比新鲜猪皮覆盖部位平均提前愈合8.5天,人工皮可作为微粒皮移植后覆盖物.  相似文献   
10.
韧性剪切带中含金石英脉的就位机制   总被引:1,自引:0,他引:1  
本文以韧性剪切带中含金石英脉的地质特征分析为基础。重点讨论:a.绿片岩相—低角闪岩相环境中的韧性剪切带内,变形岩石的韧—脆性转变既受温度、压力条件控制,又受高压流体相的广泛介入影响。对于多阶段金矿化过程,流体相的存在对岩石力学性质的转变具有更重要的意义;b.Roberts(1987)论述的含矿Riedal裂隙系(D、P、R、R′和T、P′)中不同类型裂隙内含金石英脉的就位机制有很大的差异;c.Ramsay的破裂—愈合机制可以很好地解释沿R、R′、T和某些沿D、P就位的含金石英脉的形成;d.本文作者提出液压扩容破裂机制是沿D、P方向就位的某些含金石英脉的重要就位过程。  相似文献   
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