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21.
This article reviews empirical research on memories for negative personal experiences among adults. It examines basic concepts (including neural underpinnings), theoretical models of the affect-memory relationship, and data from three sources: victims or witnesses to crimes and atrocities, "flashbulb memories" for traumatic events, and laboratory simulations of shocking experiences. Evidence suggests that memories for traumatic experiences contain more central than peripheral detail, are reasonably accurate and well-retained for very long periods, but are not completely indelible. Assertions of eyewitness memory's vulnerability to change through suggestion have overstated the evidence. Forensic and clinical implications are discussed and a plea issued for more study of the memory phenomena that characterize posttraumatic stress disorder (PTSD) and are the focus of trauma survivors' treatment.  相似文献   
22.
目的:临床评价增殖性瘢痕的颜色需要定量测量.本实验主要研究增殖性瘢痕色度的测量方法,实现瘢痕颜色的定量测量,为临床诊治提供量化依据.材料与方法:采用以光电积分式测量原理设计的色彩分析仪对增殖性瘢痕患者19人,共65个测试点按不同部位分为四组进行色度测量,并与正常组对照.用CIE-XYZ色度标准表达测量值,配合色度图直接观察瘢痕的疗效.结果:增殖性瘢痕各部位组的色度坐标值与相应的对照组比较均有显著性差异(P<0.05).结论:本实验的测量方法是有效的,能准确、定量反映增殖性瘢痕颜色的变化.可用量化指标总结、分析、报告治疗结果.  相似文献   
23.
The exact pathogenesis of hypertrophic scar and keloid formation is still unknown and a good therapy to prevent or treat these scars is lacking. Because immunological processes seem to be important in excessive scar formation, immunological cells and parameters were studied in a standardized breast reduction wound-healing model in the present study. Standardized scar samples were taken from infra-mammary breast reduction scars, 3 and 12 months following surgery. The samples were investigated for their number of mast cells, Langerhans cells, T-lymphocytes, and macrophages, and the presence of interleukin-4 (IL-4) and counter-regulating interferon-gamma (gamma-IFN), in relation to the scar's clinical appearance--normal or hypertrophic. In this study, hypertrophic scar formation was significantly associated with an increased number of epidermal Langerhans cells (p=0.0001) and significantly (p<0.05) increased expression of epidermal IL-4. No relationship was found between mast cell, T-lymphocyte and macrophage numbers or gamma-IFN staining and the formation of normal or hypertrophic scars. These results, combined with previous observation of abnormal keratinocyte behaviour in this context, indicate that the epidermal immune barrier plays an important role in the development of hypertrophic scars.  相似文献   
24.
The effects of traumatic brain injury (TBI) on hippocampal long-term potentiation (LTP) and cellular excitability were assessed at postinjury days 2, 7, and 15. TBI was induced using a well-characterized central fluid-percussion model. LTP of the Schaffer collateral/commissural system was assessed in vivo in urethane-anesthetized rats. Significant LTP of the population excitatory postsynaptic potential (EPSP) slope was found only in controls, and no recovery to control levels was observed for any postinjury time point. Four measurement parameters reflecting pyramidal cell discharges (population spike) indicated that TBI significantly increased cellular excitability at postinjury day 2: (1) pretetanus baseline recording showed that TBI reduced population spike threshold and latency; (2) tetanic stimulation (400 Hz) increased population spike amplitudes to a greater degree in injured animals than in control animals; (3) tetanus-induced population spike latency shifts were greater in injured cases; and (4) tetanic stimulation elevated EPSP to spike ratios (E-S potentiation) to a greater degree in injured animals. These parameters returned to control levels, as measured on postinjury days 7 and 15. These results suggest that TBI-induced excitability changes persist at least through 2 days postinjury and involve a differential impairment of mechanisms subserving LTP of synaptic efficacy and mechanisms related to action potential generation  相似文献   
25.
From July 1979 to December 1985 we observed 51 patients with traumatic lesions of the descending thoracic aorta. Twenty-nine had acute ruptures, mostly accompanied by multiple injuries, and 27 had to be operated upon immediately. Twenty-two patients (19 males, 3 females) had chronic traumatic aneurysms of the descending thoracic aorta (more than six weeks after trauma). Mean age at the time of trauma was 24 years. Mean age at time of surgery was 36.5 years. Twelve patients were symptomatic. All were treated surgically. At surgery, complete aortic disruption was found in 15 patients and partial rupture in seven. We did not use aortic shunting of any kind, only aortic cross-clamping. Hypertension was controlled by intravenous drug infusion. The ruptured aortic segment was replaced in all cases by prosthetic Dacron graft. There were no operative deaths. One patient (age 77) died 11 weeks after surgery from multiple organ failure. One case of postoperative paraplegia was observed. This patient recovered almost completely from his neurological deficit.  相似文献   
26.
目的探讨复发性剖宫产瘢痕部位妊娠(RCSP)发生的相关因素及处理。方法选取2015年1月至2021年1月于川北医学院附属医院妇产科确诊的463例CSP并行聚焦超声消融(FUAS)或子宫动脉介入栓塞(UAE)联合宫腔镜手术治疗患者,随访其再妊娠情况,失访72例,成功随访391例,117例再次妊娠,24例为RCSP。回顾性分析RCSP患者的临床资料和处理方式。结果391例CSP患者,122例行FUAS联合宫腔镜手术,34例再次妊娠,5.9%(2/34)为RCSP;269例行UAE联合宫腔镜手术,83例再次妊娠,26.5%(22/83)为RCSP。UAE组RCSP发生率高于FUAS组,差异有统计学意义(P<0.05)。24例RCSP患者,22例行FUAS联合宫腔镜手术,2例行UAE联合宫腔镜手术,均一次性治疗成功。RCSP患者中,79.2%(19/24)剖宫产≥2次,87.5%(21/24)人工流产≥2次,70.8%(17/24)子宫下段瘢痕厚度≤3 mm。结论既往多次剖宫产史、多次人工流产史、子宫下段瘢痕厚度偏薄及CSP初次治疗方式可能与CSP复发相关。FUAS联合宫腔镜手术是CSP及RSCP的适宜治疗方式。  相似文献   
27.
ObjectiveAmong downstream interleukin-18 (IL-18) targets, Fas ligand (FasL) in particular, has been strongly implicated in many conditions. Our study aims to explore the role of IL-18 in hypertrophic scar through enhancing FasL expression.MethodsIL-18 expression in hypertrophic scar tissues and normal tissues were explored by immunohistochemistry, qRT-PCR and Western blotting, and the expression of IL-18 in normal skin fibroblasts and hypertrophic scar fibroblasts by immunofluorescence. Hypertrophic scar fibroblasts treated with recombinant human IL-18 (rhIL-18) were assessed with MTT, Annexin V-FITC/PI, qRT-PCR, ELISA and western blotting. In the hypertrophic scar of rabbit ears, rhIL-18 was injected to determine histological changes with HE and Masson staining. Additionally, the scars were rated based on contour and overall severity using a visual analog scale scores (VAS).ResultsIL-18 was decreased in hypertrophic scar tissues and fibroblasts compared to normal skin tissues and fibroblasts, respectively. Decreased proliferation and increased apoptosis of hypertrophic scar fibroblasts were found after rhIL-18 treatment with enhanced expression of FasL, sFasL FADD, Caspase-8, Caspase-9 and Caspase-3 in a dose-dependent manner. The VAS and thickness of scars in rabbit ears was decreased as time went on after rhIL-18 treatment, with decreases in scar elevation index (SEI) and the increases in FasL expression.ConclusionIL-18 curbs proliferation and promotes apoptosis of hypertrophic scar fibroblasts by enhancing FasL expression. IL-18is a potential target for treatment of hypertrophic scar.  相似文献   
28.
The purpose of this systematic literature review is to critically evaluate split-thickness skin graft (STSG) donor-site morbidities. The search of peer-reviewed articles in three databases from January 2009 to July 2019 identified 4271 English-language publications reporting STSG donor-site clinical outcomes, complications, or quality of life. Of these studies, 77 met inclusion criteria for analysis. Mean time to donor-site epithelialization ranged from 4.7 to 35.0 days. Mean pain scores (0–10 scale) ranged from 1.24 to 6.38 on postoperative Day 3. Mean scar scores (0–13 scale) ranged from 0 to 10.9 at Year 1. One study reported 28% of patients had donor-site scar hypertrophy at 8 years. Infection rates were generally low but ranged from 0 to 56%. Less frequently reported outcomes included pruritus, wound exudation, and esthetic dissatisfaction. Donor-site wounds underwent days of wound care and were frequently associated with pain and scarring. Widespread variations were noted in STSG donor-site outcomes likely due to inconsistencies in the definition of outcomes and utilization of various assessment tools. Understanding the true burden of donor sites may drive innovative treatments that would reduce the use of STSGs and address the associated morbidities.  相似文献   
29.
Injury-related morbidity and mortality have been one of the most common causes of loss in productivity across all geographic distributions. It remains to be a global concern despite a continual improvement in regional and national safety policies. The establishment of trauma care systems and advancements in diagnostics and management have improved the overall survival of severely injured. A better understanding of the physiopathological and immunological responses to injury led to a significant shift in trauma care from “Early Total Care” to “Damage Control Orthopedics.” While most of these algorithms were tailored to the philosophy of “life before limb,” the impact of improper fracture management on disability and societal loss is increasingly being recognized. Recently, “Early Appropriate Care” of extremities has gained importance; however, its implementation is influenced by regional health care policies, available resources, and expertise and varies between low and high-income countries. A review of the literature was performed using PubMed, Embase, Web of Science, and Scopus databases on articles published from 1990 to 2020 using the Mesh terms “Polytrauma,” “Multiple Trauma,” and “Fractures.” This review aims to consolidate on guidelines and available evidence in the management of extremity injuries in a polytraumatized patient to achieve better clinical outcomes of these severely injured.  相似文献   
30.
目的探讨丹皮酚对增生性瘢痕成纤维细胞的抑制作用。方法自2018年9月至2020年6月北部战区总医院烧伤整形科提取原代增生性瘢痕成纤维细胞后,将细胞平分为4组,分别采用0μmol/L(对照组)、50μmol/L、100μmol/L的丹皮酚及10μmol/L的5-氟尿嘧啶(5-Fu)处理;CCK-8实验检测细胞处理后第0、3、5、7天的增殖情况。处理3 d后通过ELISA实验检测增生性成纤维细胞中活性氧基团或分子、丙二醛和超氧化物歧化酶的含量;Western blot实验检测丹皮酚对于细胞中TGF-β1、Ⅰ和Ⅲ型胶原的表达情况。结果50、100μmol/L的丹皮酚和10μmol/L的5-FU分别作用于细胞3 d后与对照组相比,对于细胞增殖的抑制率分别为(32.63±3.06)%、(46.41±4.41)%和(45.32±9.26)%,组间比较差异显著,具有统计学意义(P<0.05)。丹皮酚能够显著下调增生性成纤维细胞中ROS和MDA的表达情况,上调SOD的含量,降低TGF-β1、Ⅰ和Ⅲ型胶原的表达。结论丹皮酚能够抑制增生性瘢痕成纤维细胞的生长、减轻氧化应激损伤,下调TGF-β1和胶原的表达。  相似文献   
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