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Hepatitis E and meat carcasses   总被引:2,自引:0,他引:2       下载免费PDF全文
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A role for decorin in cutaneous wound healing and angiogenesis   总被引:2,自引:0,他引:2  
Decorin is known to influence tissue tensile strength and cellular phenotype. Therefore, decorin is likely to have an impact on tissue repair, including cutaneous wound healing. In this study, cutaneous healing of both excisional and incisional full‐thickness dermal wounds was studied in decorin‐deficient (Dcn?/?) animals. A statistically significant delay in excisional wound healing in the Dcn?/? mice occurred at 4 and 10 days postwounding and, in incisional wounds at 4, 10, and 18 days when compared with wild‐type (Dcn?/?) controls. Fibrovascular invasion into polyvinylalcohol sponges was significantly increased by day 18 in Dcn?/? mice relative to Dcn+/+ mice. The 18‐day sponge implants in the Dcn?/? mice showed a marked accumulation of biglycan when compared with the corresponding implants in Dcn+/+ mice. Thus, regulated production of decorin may serve as an excellent therapeutic approach for modifying impaired wound healing and harmful foreign body reactions.  相似文献   
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PURPOSE: This study was designed to assess pelvic bone temperature during typical treatment regimens of transurethral ultrasound thermal ablation of the prostate to establish guidelines for limiting bone heating. METHODS: Treatment with transurethral planar, curvilinear, and sectored tubular applicators was simulated using an acoustic and biothermal pelvic model that accommodates applicator sweeping, boundary temperature control, and changes in perfusion and attenuation with thermal dose to more accurately model ultrasound energy penetration. The effects of various parameters including power and frequency (5-10 MHz) on bone heating were assessed for a range of prostate cross-sections (3-5 cm) and bone distances (1-3 cm). RESULTS: All devices can produce significant bone heating (temperatures >50 degrees C, thermal dose >240 EM(43 degrees C)) without optimization of applied frequency or power for bone <3 cm from the prostate boundary. In small glands ( approximately 3 cm) increasing operating frequency of curvilinear and planar devices can increase bone temperatures, whereas the tubular applicator can be used at 10 MHz to avoid likely bone damage. In larger prostates (4-5 cm wide) increasing frequency reduces bone heating but can substantially increase treatment time. Lowering power can reduce bone temperature but may increase thermal dose by increasing treatment duration. All applicators can be used to treat glands 4-5 cm with limited bone heating by selecting appropriate power and frequency. CONCLUSIONS: Pubic bone heating during ultrasound thermal therapy of the prostate can be substantial in certain situations. Successful realization of this therapy will require patient-specific treatment planning to optimally determine power and frequency in order to minimize bone heating.  相似文献   
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Central venous catheters (CVCs) are now a routine part of patient management in the intensive care unit (ICU). Over time, a vast amount of literature associated with the use and care of CVCs has accumulated. The purpose of this article is to discuss the literature associated with the care of these devices in a narrative format. Although particular attention is paid to infection control issues, other fundamental areas such as catheter design, dressings, line changing and post insertion management are also discussed. The article goes on to look at the future of CVC design and concludes with an analysis of future developments related to CVCs.  相似文献   
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医疗改革是一个世界性难题,各国在医疗改革中都会遇到各自相关的问题。改革艰巨,但并不是不可能完成,本文作者认为,通过关注以分区的方式提供医疗服务可以让医疗改革取得实效。本文从划定分区边界的方式出发,介绍了制定分区医疗战略的五个步骤,并讨论了各医疗系统成功实施各自战略所需采取的措施,这也可以为我国正在推行的医疗改革提供一定的借鉴和参考。  相似文献   
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ML-05, a modified form of the hemolytic and cytotoxic bacterial toxin, streptolysin O, is currently being investigated as a treatment for collagen-related disorders such as scleroderma and fibrosis. Furthermore, ML-05 may be effective in promoting wound healing and alleviating the formation of hypertrophic scars and keloids. To investigate the effects of ML-05 on wound-healing processes, in vitro wound-healing scratch assays (using human primary epidermal keratinocytes and dermal fibroblasts) and a human skin organ culture wound model were utilized. ML-05 markedly enhanced keratinocyte migration and proliferation in wound scratch assays. ML-05 did not affect either proliferation or migration of dermal fibroblasts, indicating that ML-05's effects on cell migration/proliferation may be keratinocyte-specific. ML-05 was tested in a dose-dependent manner in a skin organ culture wound model using two different application methods: Through the culture media (dermal exposure) or direct topical treatment of the wound surface. ML-05 was found to accelerate wound healing as measured by reepithelialization, particularly after topical application. Therefore, ML-05 may have potential as a wound-healing agent that promotes reepithelialization through stimulation of keratinocyte migration and proliferation.  相似文献   
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Neurologic complications are common after transplantation and affect 30-60% of transplant recipients. The etiology of most of the posttransplant neurologic disorders is related to the opportunistic infections, both systemic and involving central nervous system (CNS), toxicity of immunosuppressive medications, and the metabolic insult created by the underlying primary disease and the transplant procedure. Neuroimaging studies are one of the key tools in the evaluation and enable early diagnosis of neurologic complications in transplant patients, especially posterior reversible leukoencephalopathy syndrome, central pontine myelinolysis, intracerebral hemorrhage, and fungal and bacterial abscesses. Magnetic resonance imaging (MRI) is the preferred technique, but each of the available neuroimaging techniques offers a unique insight into the pathophysiologic mechanisms underlying neurologic complications of transplantation. The role of neuroimaging in this population includes early detection of calcineurin inhibitor neurotoxicity, opportunistic infections, neoplasia, metabolic disorders, or cerebrovascular diseases. In addition, we can monitor longitudinal progression of disease and treatment response.  相似文献   
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