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41.
Within the last ten years, 79 patients were treated for 114 chronically contaminated, intractable irradiation wounds using various methods of the modern plastic surgery. Radical excision of the devitalised contaminated tissue has been impracticable in 25 cases due to the risk of life-threatening complications or significant functional loss. Different types of flaps such as cutaneous, fasciocutaneous, musculocutaneous, split muscle, isolated vascularised fascia and greater omentum have been used. Despite the incomplete excision, 84% of wounds healed primarily. The essential factor for good wound healing seems to be the biologic activity (BA) of the flap's deep tissue layer that directly contacts the wound bed. BA includes density of the vascular net, ability of neovascularisation, plasticity and specific immunological capacities. It seems to be possible to classify the flaps according to the BA level. Tissue defects in which the chances for radical debridement are poor need the highest BA level in the flap reconstruction.Presented to the European Congress on Wound Healing and Skin Physiology, Bochum, Germany, 1992  相似文献   
42.
A total of 117 vital skin wounds (post infliction intervals between a few seconds and 7 months), 20 postmortem wounds and skin specimens with beginning or advanced signs of putrefaction were investigated. Different markers for macrophage maturation (27 E 10, RM 3/1, 25 F 9, G 16/1) were analyzed by immunohistochemistry. The early stage inflammation marker 27 E 10 stained macrophages, but also monocytes and neutrophilic granulocytes localized in blood vessels or bleeding induced postmortem and therefore provided no further information for a forensic wound age estimation in comparison to the routine histological detection of macrophages. The antigens recognized by the RM 3/1- (intermediate stage inflammation marker) and 25 F 9-antibodies (late stage inflammation marker) were expressed exclusively by histiocytes and inflammatory cells that had migrated from the blood vessels as part of the acute inflammatory response associated with an intravital reaction. The morphometrical analysis revealed positive results (defined as at least a two-fold increase in number in 2 or more microscope fields when compared to the maximum value of histiocytes found in uninjured skin) for the RM 3/1- or 25 F 9-antibody earliest in wounds aged 7 or 11 days, respectively. Similarly to the 25 F 9-antibody, the chronic stage inflammation marker (G 16/1) reacted with a macrophage subpopulation first detectable 12 days after wounding but showed positive results in a comparably reduced percentage of cases. On the other hand, this marker did not stain a relevant number of resident macrophages thus facilitating the evaluation of the specimens. The markers 27 E 10, RM 3/1 and 25 F 9 are also useful for the evaluation of slightly - even though the staining intensity was considerably reduced - but not advanced putrefied skin. Therefore, the immunohistochemical analysis of the corresponding antigens can possibly contribute to an age estimation of wounds with advanced post infliction intervals obtained from corpses with longer - but limited - postmortem intervals.
Zusammenfassung Insgesamt wurden 117 vitale Hautwunden (Überlebenszeit wenige Sekunden bis 7 Monate), 20 postmortal gesetzte Verletzungen sowie Haut mit leichten bzw. fortgeschrittenen Fäulnisveränderungen untersucht und verschiedene Marker der Makrophagen-Differenzierung (27 E 10, RM 3/l, 25 F 9 und G 16/1) analysiert. Der early stage inflammation marker 27 E 10 färbte neben Makrophagen auch Monozyten und neutrophile Granulozyten, die innerhalb von Blutgefäßen bzw. in postmortal gesetzten Blutungen lokalisiert waren und liefert somit keine Informationen zum Wundalter, die über die Möglichkeiten des Routine-histologischen Nachweises von Makrophagen hinausgingen. Die von den Antikörpern RM 3/1 (intermediate stage inflammation marker) und 25 F 9 (late stage inflammation marker) erkannten Antigene wurden ausschließlich von Histiozyten und reaktiv eingewanderten Makrophagen exprimiert. Die morphometrische Analyse ergab positive Ergebnisse (definiert als ein mindestens zweifacher Anstieg der Zellzahl in zwei oder mehr Gesichtsfeldern verglichen mit der maximal feststellbaren Zahl an Histiozyten in unverletzter Haut) bei Verwendung der Antikörper RM 3/1 bzw. 25 F 9 frühestens 7 bzw. 11 Tage nach Wundsetzung. Ab 12 Tagen Wundalter reagierte der chronic stage inflammation marker G 16/1 erstmals positiv. Das Antigen ließ sich insgesamt allerdings in einem geringeren Prozentsatz der untersuchten Wunden darstellen. Vorteilhaft ist jedoch das Fehlen einer relevanten Expression durch Histiozyten, wodurch die Auswertung der Präparate erleichtert wird. Die entsprechenden Antigene lassen sich zudem in leicht - wenn auch in einer deutlich geringeren Färbeintensität -, aber nicht forgeschritten fäulnisveränderter Haut nachweisen, so daß deren immunhistochemische Darstellung gegebensfalls auch zur Beurteilung von länger überlebten Verletzungen an Leichen mit etwas fortgeschrittener Liegezeit herangezogen werden kann.
  相似文献   
43.
The fate of ocular surface epithelial cells in response to injury of the cornea was examined. Corneal epithelial cells were labeled during DNA synthesis with [3H]thymidine 1 h prior to wounding. A 3-mm diameter epithelial defect was made in the center of the rat cornea, with the basement membrane remaining intact. Within 12 h of abrasion, labeled cells were detected in the regenerating surface. At 18 h, there was a 2.7- and 17-fold increase of labeled basal and suprabasal cells, respectively, in the epithelium adjacent to the wound, and at 24 and 30 h there was an excessive number of cell layers (up to 7) at the margin of the abrasion. Re-epithelialization progressed as a gradient of cell layers that became diminished towards the center of the wound. Completion of layers 1, 2, 3, and 4 were recorded at 24, 30, 36, and 72 h, respectively. No changes in the labeling index of the limbus or conjunctiva were noted. These results suggest that processes of centripetal and vertical migration, as well as events related to cell division, in the uninjured corneal surface are not impeded by wounding of the corneal epithelium. However, wound healing appears to require cells with a basal phenotype, presumably because of this cell type's migratory capability.  相似文献   
44.
The aim of the present study is to analyze the changes of cure rate and the main causes of death in the last 40 years, and to summarize our experience in the treatment of extensive full-thickness burn patients. The clinical characteristics, cure rate and main causes of death of 73 cases with total burned area more than 90% TBSA and full-thickness burn area more than 70% TBSA were analyzed retrospectively. Among them, 21 cases (28.8%) were cured and 52 cases (71.2%) died. The cure rate increased significantly in the recent years, and the main causes of death changed from shock and sepsis in the time period 1959–1978 to sepsis and MODS in the past two decades. Due to the improvement of early comprehensive management of burn shock, aggressive surgical approach to full-thickness burn wound and potent systemic supporting measures, the survival rate increased significantly.  相似文献   
45.
Morphometrical analysis of hemosiderin deposits in relation to wound age   总被引:3,自引:0,他引:3  
A morphometrical analysis of the extent of hemosiderin deposits in 71 human skin wounds with post-infliction intervals between 2 days and 7 months was performed. Earliest positive findings were detectable in a lesion aged 3 days, and with increasing wound age an increase in the amount of hemosiderin occurred. A value of more than 20% of the microscopic field with hemosiderin deposits was found earliest 8 days after wounding and therefore the detection of considerable amounts of hemosiderin (arbitrarily defined as 20% or more of the evaluated area) indicates a minimum wound age of approximately 1 week. Since the extent of hemosiderin formation depends upon the extent of the initial hemorrhage and a physiological reduction in the amount of this pigment with advanced wound age, slight or absent hemosiderin deposits cannot provide information on the post-infliction interval.  相似文献   
46.
Summary We analyzed the distribution of fibronectin in routinely embedded tissue specimens from 53 skin wounds and 6 postmortem wounds. In postmortem wounds a faint but focal positive staining was exclusively found at the margin of the specimens which dit not extend into the adjacent stroma. Vital wounds were classified into 3 groups. The first comprising lesions with wound ages ranging from a few seconds to 30 min, the second comprising those with wound ages upt to 3 weeks, and the third group with lesions more than 3 weeks old. Ten out of 17 lesions with a wound age up to 30 min showed a clear positive reaction within the wound area. Three specimens in this group were completely negative, while in 4 additional cases the result was not significantly different from postmortem lesions. These 7 cases were characterized by acute death with extremely short survival times (only seconds). In wounds up to 3 weeks old fibronectin formed a distinct network containing an increasing number of inflammatory cells corresponding to the wound age. In 2 cases with a survival time of 17 days and in all wounds older than 3 weeks fibronectin was restricted to the surface of fibroblasts and to parallel arranged fibers in the granulation tissue without any network structures. We present evidence that fibronectin is a useful marker for vital wounds with a survival time of more than a few minutes. Fibronectin appears before neutrophilic granulocytes migrate into the wound area. Since a faint positive fibronectin staining is seen in postmortem lesions and bleedings, we propose that only those wounds which show strong positive fibronectin staining also extending into the adjacent stroma should be regarded as vital.This study was supported by a grant from the Deutsche Forschungsgemeinschaft (grant Ei 209/3-1) and by a grant from the Friedrich-Baur-Stiftung University of Munich  相似文献   
47.
Summary Incision wounds were made on the outer ear of rats and two biopsies were taken for examination after different survival times. In each case a biopsy was made of vital tissue and a second of postmortem tissue after refrigeration for 24 h. The biopsies were exposed to a solution containing the RNA precursor3H-cytidine for 1 h, washed and fixed in formalin. Sections 5 m thick were then autoradiographically prepared and automatically evaluated using Quantimet 920. The intravital specimens showed a significant increase in3H-cytidine incorporation in the basal cell layer after survival times of 10–24 h. No increase was seen in the stratum corneum, corium or cartilage tissue. The investigated distance from the wound margin did not have any significant bearing on the results. The3H-cytidine incorporation rate in postmortem tissue was practically identical with that of vital tissue, but no increase was observed in the rate of RNA synthesis in the basal cells as a function of the age of the wound. It may therefore be assumed that this method provides no additional information as to the age of wounds in postmortem examination.Dedicated to Professor O. Pribilla on the occasion of his 70th birthday  相似文献   
48.
Effect of electrolyzed water on wound healing   总被引:1,自引:0,他引:1  
Electrolyzed water accelerated the healing of full-thickness cutaneous wounds in rats, but only anode chamber water (acid pH or neutralized) was effective. Hypochlorous acid (HOCl), also produced by electrolysis, was ineffective, suggesting that these types of electrolyzed water enhance wound healing by a mechanism unrelated to the well-known antibacterial action of HOCl. One possibility is that reactive oxygen species, shown to be electron spin resonance spectra present in anode chamber water, might trigger early wound healing through fibroblast migration and proliferation.  相似文献   
49.
目的 研究肝细胞生长因子(hepatocyte growth factor,HGF)对培养的人视网膜色素上皮(retinal pigmental epithelial,RPE)细胞增生和损伤愈合的影响。方法 MTT比色法检测细胞增生情况,相差显微和细胞计数法观察RPE细胞损伤后的愈合情况。结果 中等浓度HGF(10ng/ml)刺激RPE细胞的增生较低浓度组(0.01~1ng/m1)明显增多(P<0.05),而与高浓度(100ng/ml)组比较无统计学差异(P>0.05)。随着HGF刺激时间的延长,迁移的细胞数量增多,同一时间点,HGF处理组明显比对照组细胞数量多(P<0.05)。结论 中等浓度的HGF可促进细胞增生,对损伤后的RPE细胞有迁移作用。  相似文献   
50.
瘢痕治疗现状   总被引:5,自引:0,他引:5  
伤口愈合后瘢痕的形成与增生,一直困扰着人们,是整形美容外科急需解决的难题.增生性瘢痕或瘢痕疙瘩在临床上较常见,发病率越来越高,其产生的内因,形成的机理尚不完全清楚,目前比较一致的看法是瘢痕组织内成纤维细胞增多和胶原纤维沉积,但缺乏有效、可靠的治疗方法,未从根本上解决防治瘢痕的问题.现对瘢痕的治疗现状作一综述.  相似文献   
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