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This article focuses on the lateral arm free flap as the option that comes closest to meeting the diverse aesthetic and functional goals of phalloplasty. The authors introduce a new technique for incorporating a prefabricated neourethra within the lateral arm to permit the coexistence of an erectile prosthesis alongside a fully vascularized urethra that extends to the distal tip. The unrecognized value of the radial forearm free flap for urethroplasty is also discussed and a case of reconstruction following urethral loss is presented. Also described is how the prefabricated urethra technique may be useful for repairing severe hypospadias defects.  相似文献   
156.
Neuroprotective effects of virally delivered HSPs in experimental stroke.   总被引:3,自引:0,他引:3  
Heat shock proteins (HSPs) are molecular chaperones with essential roles in modulating the proteolytic machinery and accelerating cell repair. Heat shock protein overexpression has been observed in vivo and in vitro under stresses including heat, nutrient deprivation and ischemia. Experiments in in vivo models of stroke indicate that transgenically overexpressed or virally delivered HSPs can enhance cell survival, but cannot always reduce lesion size. This study aims to assess the effects of virally delivered HSPs in a rat middle cerebral artery occlusion model of reversible focal cerebral ischemia using noninvasive magnetic resonance imaging. Attenuated herpes simplex virus carrying HSP27, HSP70, or a LacZ control was microinjected into the striatum 3 days before ischemia. Multislice T(2)-weighted images at 24 h after ischemia indicated that lesion volume was reduced by 44% in HSP27-treated animals compared with controls (P = 0.019). No significant differences were found between HSP70-treated and control animals (P = 0.88). Immunohistochemistry and Western blots revealed that HSP27 and HSP70 expression levels were equally high in injected hemispheres, but only the former had an effect on lesion size. This is the first evidence of the efficacy of gene therapy with any viral vector expressing HSP27 in an experimental model of stroke.  相似文献   
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BACKGROUND: A concise yet accurate measurement tool is needed for use in research and practice in asthma self-management perceptions across culturally diverse patient populations. OBJECTIVES: To evaluate the psychometric properties of the 11-item Perceived Control of Asthma Questionnaire (PCAQ) and to derive a brief, psychometrically sound, and culturally sensitive measure using item response theory. METHODS: The PCAQ was administered as one of a battery of measures to 375 adults with asthma as part of an ongoing larger project studying asthma disparities. Analyses of differential item functioning (DIF) were conducted to detect the effects of sex, race/ethnicity, and health literacy on psychometric properties. RESULTS: Forty-eight percent of the sample was non-Hispanic white and 44% was African American. The mean +/- SD age was 43.7 +/- 13.7 years. The derived 6-item version, with 5 DIF items not scored, correlated highly with its full version (r = 0.903; P < .001). CONCLUSIONS: The 6-item PCAQ short form has the potential to maintain scale integrity while reducing administration time and lessening survey fatigue in studies using multiple questionnaires. DIF analyses also enabled us to understand the unique aspects of perceived asthma control in demographic groups most affected by asthma.  相似文献   
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A new HPLC method to determine Donepezil hydrochloride in tablets.   总被引:2,自引:0,他引:2  
A HPLC stability-indicating assay for Donepezil hydrochloride in tablets was developed and validated. Donepezil hydrochloride is a reversible inhibitor of acetylcholinesterase, indicated for the treatment of mild to moderate dementia of the Alzheimer's type. The HPLC method was performed with a reversed phase C18 column, detection at 268 nm and a mixture of methanol, phosphate buffer 0.02 M and triethylamine (50:50:0.5) as mobile phase. Typical retention time for Donepezil was 9 min. The method was statistically validated for linearity, accuracy, precision and selectivity following ICH recommendations. Due to its simplicity and accuracy, the method can be used for routine quality control analysis.  相似文献   
159.
PURPOSE: To evaluate prognostic factors in patients with glioblastoma treated with postoperative or primary radiotherapy. PATIENTS AND METHODS: From 1989 to 2000, a total of 100 patients underwent irradiation as part of their initial treatment for glioblastoma. All patients had undergone surgery or biopsy followed by conventional external-beam radiotherapy. 85 patients who received the planned dose of irradiation (60 Gy in 30 fractions) were analyzed for the influence of prognostic factors. 73/85 (86%) of patients were given postoperative irradiation, while 12/85 (14%) of patients were primarily treated with radiotherapy after biopsy. RESULTS: The median overall survival was 10.1 months (range, 3.7-49.8 months), the 1- and 2-year survival rates were 41% and 5%, respectively. Univariate analysis revealed age < or = 55 years (p < 0.001), pre-radiotherapy hemoglobin (Hb) level > 12 g/dl (p = 0.009), and pre-radiotherapy dose of dexamethasone < or = 2 mg/day (p = 0.005) to be associated with prolonged survival. At multivariate analysis, younger age (p < 0.001), higher Hb level (p = 0.002), lower dose of dexamethasone (p = 0.026), and a hemispheric tumor location (p = 0.019) were identified as independent prognostic factors for longer survival. The median survival for patients with an Hb level > 12 g/dl was 12.1 months compared to 7.9 months for those with a lower Hb level. Contingency-table statistics showed no significant differences for the two Hb groups in the distribution of other prognostic factors. CONCLUSION: The results indicate that lower Hb level prior to radiotherapy for glioblastoma can adversely influence prognosis. This finding deserves further evaluation.  相似文献   
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