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41.
BACKGROUND: Shoe dermatitis is a form of contact dermatitis resulting from exposure to shoes. Different chemicals, in conjunction with a hot and humid environment within the shoe, give rise to allergic or irritant dermatitis. Allergic shoe dermatitis is commonly caused by constituents of rubber, leather, adhesives, and rarely by linings and dyes. AIM: To determine the frequency of various allergens in shoe dermatitis in our patients. METHODS: One hundred and nine patients suspected of having contact dermatitis due to shoe allergens were included. All patients were patch tested with the Shoe series and European Standard series. Patches were applied on the upper back and removed after 48 h. Results were read at 48, 72, and 120 h and interpreted according to International Contact Dermatitis Research Group (ICDRG) criteria. RESULTS: Of the 119 patients, 87 (73%) reacted positively to various allergens, 48% of whom showed polysensitivity. Glues (33.6%), particularly para-tert-butylphenol formaldehyde resin (PTBP-FR) (26.9%), were the leading cause of shoe dermatitis. Other allergens were leather chemicals (26.4%), potassium dichromate (16.18%), rubber allergens (7.6%), and dyes (7.6%). Shoe scrapings tested positive in 26.3% of patients. Other common allergens were nickel sulfate (22.7%), neomycin sulfate (10.1%), and cobalt chloride (8.4%). CONCLUSIONS: Considering the diversity of allergens, all patients presenting with shoe dermatitis should be patch tested with the Shoe series and a standard series to determine the etiologic allergens.  相似文献   
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Angiogenesis, development of new blood vessels, is essential for wound healing and tumor growth. A potentially important side effect of anti-angiogenic therapy can be delayed wound healing. In this study we address this issue by using a novel in vivo method utilizing fibrin containing dual porous plexiglass chambers (Fibrin Z-Chambers; F-ZC) to investigate wound healing in rats administered with SU5416 (inhibitor of Flk-1 and Flt-1, at 20 mg/kg i.p.). SU5416 treated F-ZCs developed 45% less granulation tissue (p = 0.0076) and showed a 10% reduction in microvessel density (p = 0.0009) than controls treated with drug carrier alone. The granulation tissue showed distinctly decreased collagen deposition (p = 0.0006) in SU5416 treated animals that was associated with 90% reduction in active TGF-beta 1 level. We found that tissue transglutaminase (TG), a cross-linking enzyme involved in TGF-beta 1 activation and matrix stabilization, was inhibited by SU5416. These results suggest that SU5416 delays wound healing by reducing matrix synthesis and stabilization through inhibition of TGF-beta 1 activation. This study was made feasible via the development of a unique method to study anti-angiogenic compounds that provides highly reproducible and quantitative results. Further studies are needed to evaluate in vivo whether anti-angiogenic agents alter wound healing.  相似文献   
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Does leukoaraiosis predict morbidity and mortality?   总被引:24,自引:0,他引:24  
OBJECTIVE: To determine whether leukoaraiosis predicts morbidity and mortality. BACKGROUND: Gait disturbance and leukoaraiosis both are common in the elderly. Gait disturbance predicts mortality. Leukoaraiosis may be a unifying factor to both gait disturbance and mortality. METHODS: We followed 221 patients prospectively evaluated for severity of neurologic deficits by the National Institutes of Health (NIH) stroke scale and for leukoaraiosis in seven brain regions by CT, graded as absent (n = 119, 54%), mild (in at least one of seven brain regions; n = 54, 24%), or severe (present in all seven brain regions; n = 48, 22%). Pneumonia (n = 27, 12%), falls resulting in fracture requiring hospitalization (n = 7, 3%), and death (n = 38, 17%) were end points. RESULTS: Severe leukoaraiosis predicted death (Cox hazard ratio [HR] = 2.91; 95% CI = 1.5 - 5.6), pneumonia (HR = 5.1; 95% CI = 2.4 - 10.9), death from pneumonia (HR = 8.3; 95% CI = 1.5 - 46), and falls (HR = 6.8; 95% CI = 1.5 - 30). Severe leukoaraiosis predicted a combined end point of death, pneumonia, and falls (HR = 3.5; 95% CI = 2 - 6). Other predictors were NIH stroke scale score, age, smoking, diabetes, gait score, and referral diagnosis of either dementia or Parkinsonism. Severe leukoaraiosis remained a predictor after adjustment for these other factors (HR = 2.2; 95% CI = 1.2 - 3.9), but was borderline after adjusting for gait (HR = 1.96; 95% CI = 0.97 - 3.94; p = 0.061). The combination of severe leukoaraiosis and gait disturbance had the highest risk (HR = 4.4; 95% CI = 2.4 - 7.9). CONCLUSION: Severe leukoaraiosis predicts morbidity and mortality independently of preexisting neurologic deficits. The combination of leukoaraiosis and gait disturbance carries a poor prognosis.  相似文献   
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The risk factors for mortality were analysed in a consecutive group of 1158 children presenting to the Aga Khan University Medical Center, Karachi, with multidrug resistant typhoid fever that had been proved on culture. There were 19 deaths, representing an overall case fatality rate of 1.6%. Multidrug resistant typhoid was associated with a more severe clinical illness and higher rates of toxicity, hepatomegaly, hypotensive shock, and death. Irrespective of drug resistance status, typhoid fever was found to be a more severe illness in young infants with significantly higher rates of diarrhoea, hypotensive shock, and mortality. Univariate analysis of admission characteristics associated with increased risk for mortality revealed significant association with younger age (p < 0.05), hypotensive shock or hypothermia (p < 0.001), obtundation (p < 0.001), seizures (p < 0.05), anaemia at admission (p < 0.005), and leucocytosis (p < 0.001). Logistic regression analysis of risk factors for mortality showed persistent association of hypothermia, toxicity, and anaemia with mortality. The data provides evidence that multidrug resistant typhoid in childhood is associated with increased risk of mortality, especially in infancy and closer attention to several risk factors for increased morbidity and case fatality rates may lead to improved outcome of treatment.  相似文献   
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Photosynthetic microorganisms can produce hydrogen when illuminated, and there has been considerable interest in developing this to a commercially viable process. Its appealing aspects include the fact that the hydrogen would come from water, and that the process might be more energetically efficient than growing, harvesting, and processing crops. We review current knowledge about photobiological hydrogen production, and identify and discuss some of the areas where scientific and technical breakthroughs are essential for commercialization. First we describe the underlying biochemistry of the process, and identify some opportunities for improving photobiological hydrogen production at the molecular level. Then we address the fundamental quantum efficiency of the various processes that have been suggested, technological issues surrounding large-scale growth of hydrogen-producing microorganisms, and the scale and efficiency on which this would have to be practiced to make a significant contribution to current energy use.  相似文献   
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Beh?et's disease is a chronic relapsing form of vasculitis affecting multiple organs. Central nervous system involvement is a common presentation. Tumor necrosis factor-alpha (TNF-alpha) is considered to play a major role in the disease pathogenesis. We describe a patient with a long history of neuro-Beh?et's disease who showed a remarkable response to infliximab therapy. Given the variable and limited success of other interventions, the use of anti-TNF-alpha therapy seems to be effective for patients with refractory disease.  相似文献   
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