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71.
Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder of bile acid synthesis, caused by impaired hydroxylation of cholesterol side chains due to deficiency of the mitochondrial enzyme sterol 27-hydroxylase (CYP27A1), leading to accumulation of cholestanol and cholesterol in brain and other tissues. Elevated plasma cholestanol serves as a key marker for the clinical diagnosis of CTX. In the present report we describe a young man with CTX who was on high dose steroids for a misdiagnosed chronic inflammatory demyelinating polyneuropathy (CIDP) and had normal level of serum cholestanol. When steroids were discontinued, markedly elevated serum cholestanol was measured concomitant with marked clinical worsening. This observation may imply that steroids can lower plasma cholestanol, possibly by directly inducing residual CYP27A1 activity or by inducing alternative pathways for cholestanol elimination.  相似文献   
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PURPOSE: To determine the effect of isolation rooms on the direct spread of nosocomial infections (NIs) owing to cross-colonization in a pediatric intensive care unit (PICU). MATERIALS AND METHODS: This 6-month comparative clinical study used retrospective data from 1992 (an open single-space unit) and prospective surveillance from 1995 (individual rooms) to assess the effectiveness of the latter design on the control of NIs in critically ill pediatric patients. Patients admitted to the PICU for at least 48 hours underwent a microbiologic survey. RESULTS: The average number of NIs per patient was higher in 1992 (3.62 +/- 0.7, 78 patients) compared with 1995 (1.87 +/- 0.2, 115 patients). Bacterial NIs were caused by gram-positive cocci (33.3%) and aerobic gram-negative bacilli (66.6%). Fungemia in all cases was caused by Candida albicans. Similarly, length of stay was significantly higher in 1992 compared with 1995 (25 +/- 6 and 11 +/- 6 days, respectively; P <.05). There was a significant reduction of respiratory and urinary tract episodes of NI as well as catheter-related infections in the separate room arrangement. CONCLUSIONS: Our preliminary analysis suggests a possible beneficial effect of single isolation rooms in reducing NI rate in the PICU. Hence, the influence of room isolation on NIs in pediatric intensive care warrants further investigation.  相似文献   
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Loss of PTEN facilitates HIF-1-mediated gene expression   总被引:64,自引:2,他引:64       下载免费PDF全文
In glioblastoma-derived cell lines, PTEN does not significantly alter apoptotic sensitivity or cause complete inhibition of DNA synthesis. However, in these cell lines PTEN regulates hypoxia- and IGF-1-induced angiogenic gene expression by regulating Akt activation of HIF-1 activity. Restoration of wild-type PTEN to glioblastoma cell lines lacking functional PTEN ablates hypoxia and IGF-1 induction of HIF-1-regulated genes. In addition, Akt activation leads to HIF-1alpha stabilization, whereas PTEN attenuates hypoxia-mediated HIF-1alpha stabilization. We propose that loss of PTEN during malignant progression contributes to tumor expansion through the deregulation of Akt activity and HIF-1-regulated gene expression.  相似文献   
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In 2016, over 5 million reconstructive procedures were performed in the United States. The recent successes of clinical vascularized composite allotransplantations, hand and face transplantations included, established the tremendous potential of these life‐enhancing reconstructions. Nevertheless, due to limited availability and lifelong immunosuppression, application is limited. Long‐term banking of composite transplants may increase the availability of esthetically compatible parts with partial or complete HLA matching, reducing the risk of rejection and the immunosuppressive burden. The study purpose was to develop efficient protocols for the cryopreservation and transplantation of a complete rodent limb. Directional freezing is a method in which a sample is cooled at a constant‐velocity linear temperature gradient, enabling precise control of the process and ice crystal formation. Vitrification is an alternative cryopreservation method in which the sample solidifies without the formation of ice crystals. Testing both methods on a rat hindlimb composite tissue transplantation model, we found reliable, reproducible, and stable ways to preserve composite tissue. We believe that with further research and development, cryopreservation may lead to composite tissue “banks.” This may lead to a paradigm shift from few and far apart emergent surgeries to wide‐scale, well‐planned, and better‐controlled elective surgeries.  相似文献   
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Erectile dysfunction (ED) is a common condition in aging men, with a prevalence of 52% in men aged 40 to 70 years. It is frequently associated with several comorbid conditions, including cardiovascular disease, lower urinary tract symptoms, and testosterone deficiency. These conditions often have major consequences on the quality of life of patients and require adequate evaluation by the primary care practitioner. Complaints of ED, therefore, serve as a marker for these conditions and give the practitioner an opportunity to prevent the consequences of a delay in treatment. In this article, the evidence behind these associations is described.  相似文献   
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Asymptomatic carotid artery stenosis (ACAS)  相似文献   
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