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51.
Progression to AIDS in HIV-infected homosexual and bisexual men with hairy leukoplakia and oral candidiasis. 总被引:4,自引:0,他引:4
M H Katz D Greenspan J Westenhouse N A Hessol S P Buchbinder A R Lifson S Shiboski D Osmond A Moss M Samuel 《AIDS (London, England)》1992,6(1):95-100
OBJECTIVE: This study was designed to assess the significance of HIV-related oral lesions in predicting the rate of progression to AIDS. DESIGN: Cohorts were investigated prospectively, and oral examinations were performed by clinicians trained in the diagnosis of oral lesions. SETTING: We studied three existing cohorts of homosexual and bisexual men in San Francisco, California, USA. PARTICIPANTS: Of the HIV-infected men who received standardized oral examinations (n = 791), 603 were eligible for analysis of baseline examinations and 448 for analysis of follow-up examinations. MAIN OUTCOME MEASURES: We determined time from presence of oral lesion at baseline or follow-up examination, or from participant self-reported history of the lesion, to diagnosis of AIDS. RESULTS: Using proportional hazard regression and stratifying by CD4 lymphocyte count at the time of baseline oral examination, we found that the rate of development of AIDS was increased among men with hairy leukoplakia [relative hazard, 1.8; 95% confidence interval (CI), 1.2-2.7], oral candidiasis (relative hazard, 7.3; 95% CI, 3.1-17.3), and both lesions (relative hazard, 3.1; 95% CI, 1.6-6.1) compared with men with normal findings. On follow-up examination, stratifying for CD4 count, the rate of progression to AIDS was similar for those with hairy leukoplakia compared with those with oral candidiasis. The progression rate from oral candidiasis to AIDS was faster from presence on baseline examination than from presence on follow-up examination or from self-reported history of the lesion. CONCLUSION: The presence of oral candidiasis and/or hairy leukoplakia on baseline examination confers independent prognostic information and should be incorporated into HIV-staging schemes. 相似文献
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55.
Pregabalin‐withdrawal encephalopathy and splenial edema: A link to high‐altitude illness? 总被引:1,自引:0,他引:1
A postherpetic-neuralgia patient abruptly discontinued pregabalin. Thirty hours later, unexplained nausea, headache, and ataxia developed, progressing to delirium 8 days later. Magnetic resonance imaging indicated T2-hyperintense lesions of her splenium. Similar magnetic resonance imaging abnormalities, interpreted as focal vasogenic edema, develop in some epileptic patients after rapid anticonvulsant withdrawal. Patients with high-altitude cerebral edema have similar splenial-predominant magnetic resonance imaging abnormalities that accompany these same neurological symptoms. This case is the first to associate anticonvulsant-withdrawal splenial abnormalities with neurological symptoms, with gabapentin-type anticonvulsants, and is among the first in nonepileptic patients, suggesting that sudden anticonvulsant withdrawal alone, unaccompanied by seizures, can initiate symptomatic focal brain edema. The similarity of this syndrome to high-altitude cerebral edema suggests a possible common pathophysiology and offers potential therapies. 相似文献
56.
Buchbinder R 《The New England journal of medicine》2004,350(21):2159-2166
57.
Leichter I Lederman R Buchbinder SS Bamberger P Novak B Fields S 《AJR. American journal of roentgenology》2004,182(3):705-712
OBJECTIVE: The objective of this study was to compare the diagnostic role of features reflecting the geometry of clusters with features reflecting the shape of the individual microcalcification in a mammographic computer-aided diagnosis system. MATERIALS AND METHODS: Three hundred twenty-four cases of clustered microcalcifications with biopsy-proven results were digitized at 42-microm resolution and analyzed on a computerized system. The shape factor and number of neighbors were computed for each microcalcification, and the eccentricity of the cluster was computed as well. The shape factor is related to the individual microcalcification; the average number of neighbors and the cluster eccentricity reflect the cluster geometry. Stepwise discriminant analysis was used to evaluate the contribution of the extracted features in predicting malignancy. The performance of a classifier based on the features selected by stepwise discriminant analysis was evaluated by receiver operating characteristic (ROC) analysis. RESULTS: To obtain the best discrimination model, we used stepwise discriminant analysis to select the average number of neighbors and the shape of the individual microcalcification, but excluded cluster eccentricity. A classification scheme assigned the average number of neighbors a weighting factor, which was 1.49 times greater than that assigned to the shape factor of the individual microcalcification. A scheme based only on these two features yielded an ROC curve with an area under the curve (A(z)) of 0.87, indicating a positive predictive value of 61% for 98% sensitivity. CONCLUSION: Computerized analysis permitted calculations reflecting the shape of individual microcalcification and the geometry of clusters of microcalcifications. For the computerized classification scheme studied, the cluster geometry was more effective in differentiating benign from malignant clusters than was the shape of individual microcalcification. 相似文献
58.
Mercado CL Naidrich SA Hamele-Bena D Fineberg SA Buchbinder SS 《The breast journal》2004,10(5):427-432
The objective of this study was to evaluate the spectrum of sonographic findings in pseudoangiomatous stromal hyperplasia (PASH) of the breast when it presents as a tumoral mass with pathologic correlation. Breast sonogram studies of 13 patients with 13 pathologically proven PASH lesions were retrospectively reviewed. The morphologic characteristics of the lesions as seen on ultrasound were evaluated and correlated with histopathologic findings. Sonography demonstrated most lesions, 11 of 13, to be hypoechoic in echotexture. One lesion was isoechoic in echotexture, also demonstrating small internal cysts, and one was predominantly hyperechoic. Two of the 11 hypoechoic lesions also demonstrated a complex heterogeneous pattern with a central hypoechoic area and a peripheral echogenic rim. All lesions were oval in shape with the long axis of the lesion parallel to the chest wall. None of the lesions demonstrated posterior acoustic shadowing. PASH lesions of the breast have a varied sonographic appearance. Knowledge of the spectrum of morphologic features shown on sonography can be helpful in the diagnosis of this entity. 相似文献
59.
Treatment of allergic bronchopulmonary aspergillosis (ABPA) has remained both problematic as well as controversial. Although the sheet anchor in treatment of ABPA still remains steroids, various workers have tried oral antifungals (fluconazole and itraconazole) with encouraging results. This study evaluates the effect of fluconazole or itraconazole in the treatment of ABPA patients and compares them with the patients who had received palliative therapy other than antifungals. Case records of 44 proven cases of ABPA treated at our referral service hospital during February 1998 to April 2001 were analyzed. In addition to oral and inhaled bronchodilators, 16 patients received fluconazole 150 mg OD and 13 patients itraconazole 200 mg OD for six months. Response to therapy was assessed clinically, radiologically and by spirometry every 3 months. Patients who did not receive antifungals had chronic course characterized by airway obstruction, recurrent pulmonary consolidation and obstructive defect on pulmonary function test (PFT). Patients treated with itraconazole had better control of asthma symptoms, less requirement of reliever inhalers, steroids and lesser exacerbations of asthma during follow-up even after stopping antifungal. Fluconazole group had better control of symptoms but improvement in other parameters was not statistically significant. From this study it was evident that itraconazole improved the symptoms of airway obstruction, pulmonary functions, pulmonary opacities and decreased exacerbations during follow up.Key Words: Allergic bronchopulmonary aspergillosis, Fluconazole, Itraconazole 相似文献
60.
Colfax G Vittinghoff E Husnik MJ McKirnan D Buchbinder S Koblin B Celum C Chesney M Huang Y Mayer K Bozeman S Judson FN Bryant KJ Coates TJ;EXPLORE Study Team 《American journal of epidemiology》2004,159(10):1002-1012
Prior reports associating substance use with sexual risk behavior have generally used summary measures and have not adjusted for participants' background levels of substance use. In this 1999-2001 US study (the EXPLORE study), the authors determined whether substance use during sex was independently associated with sexual risk during recent sexual episodes, as reported by 4,295 human immunodeficiency virus-negative men who have sex with men. The main outcome measure was serodiscordant unprotected anal sex (SDUA). The influence of participant-level characteristics was examined by using repeated-measures logistic models. In assessing the influence of episode-level predictors on SDUA, the influence of participant-level characteristics, including 6-month substance use, was removed by using conditional logistic regression, in effect making each participant his own control. The authors also adjusted for partner characteristics. Eleven percent of participants reported heavy alcohol use, 37% used poppers, 19% sniffed cocaine, and 13% used amphetamines. In the participant-level analysis, use of poppers, amphetamines, and sniffed cocaine as well as heavy alcohol use in the prior 6 months were independently associated with SDUA. In the conditional analysis, consumption of > or = 6 alcoholic drinks or use of poppers, amphetamines, or sniffed cocaine just before or during sex was independently associated with SDUA. The authors concluded that programs aimed at preventing human immunodeficiency virus transmission should emphasize the influence of substance use during sex on increased risk behavior. 相似文献