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101.
Homocystine, β-alanine and significant elevations of methionine, threonine and histidine were found in the serum of seven patients with progressive systemic sclerosis as a result of 6-azauridine triacetate treatment. Substantial increases in urinary β-alanine, β-aminoisobutyrate and homocystine were also observed. Metabolic changes involving inhibition of pyridoxal phosphate-dependent enzymes are discussed and suggested as a possible mechanism of these metabolic alterations.  相似文献   
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Carotid arteriograms on three patients with unilateral pulsatile tinnitus demonstrated an ipsilateral atypical trigeminal artery extending from the cavernous portion of the internal carotid artery to form the posterior inferior cerebellar artery. Illustrations and a dissection of a human fetus with a similar finding show this artery crossing the cochlear nerve near its insertion in the pons. Evidence is presented suggesting that neurovascular compression of the eighth nerve is the source of pulsatile tinnitus in these patients.  相似文献   
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BACKGROUND: National data from the mid-1990s demonstrated that many eligible patients did not receive highly active antiretroviral therapy (HAART) and that racial and gender disparities existed in HAART receipt. We examined whether demographic disparities in the use of HAART persist in 2001 and if outpatient care is associated with HAART utilization. METHODS: Demographic, clinical, and pharmacy utilization data were collected from 10 US HIV primary care sites in the HIV Research Network (HIVRN). Using multivariate logistic regression, we examined demographic and clinical differences associated with receipt of HAART and the association of outpatient utilization with HAART. RESULTS: In our cohort in 2001, 84% of patients received HAART and 66% had 4 or more outpatient visits during calendar year (CY) 2001. Of those with 2 or more CD4 counts below 350 cells/mm in 2001, 91% received HAART; 82% of those with 1 CD4 test result below 350 cells/mm received HAART; and 77% of those with no CD4 counts below 350 cells/mm received HAART. Adjusting for care site in multivariate analyses, age >40 years (adjusted odds ratio [AOR] = 1.13), male gender (AOR = 1.23), Medicaid coverage (AOR = 1.16), Medicare coverage (AOR = 1.73), having 1 or more CD4 counts less than 350 cells/mm (AOR = 1.33), and having 4 or more outpatient visits in a year (OR = 1.34) were significantly associated with an increased likelihood of HAART. African Americans (odds ratio [OR] = 0.84) and those with an injection drug use risk factor (OR = 0.86) were less likely to receive HAART. CONCLUSIONS: Although the overall prevalence of HAART has increased since the mid-1990s, demographic disparities in HAART receipt persist. Our results support attempts to increase access to care and frequency of outpatient visits for underutilizing groups as well as increased efforts to reduce persistent disparities in women, African Americans, and injection drug users (IDUs).  相似文献   
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Alveolar echinococcosis (AE) is caused by the metacestode stage of the fox tapeworm Echinococcus multilocularis and causes severe disease in the human liver, and occasionally in other organs, that is fatal when treatment is unsuccessful. The present chemotherapy against AE is based on mebendazole and albendazole. Albendazole treatment has been found to be ineffective in some instances, is parasitostatic rather than parasiticidal, and usually involves the lifelong uptake of large doses of drugs. Thus, new treatment options are urgently needed. In this study we investigated the in vitro and in vivo efficacy of mefloquine against E. multilocularis metacestodes. Treatment using mefloquine (20 μM) against in vitro cultures of metacestodes resulted in rapid and complete detachment of large parts of the germinal layer from the inner surface of the laminated layer within a few hours. The in vitro activity of mefloquine was dependent on the dosage. In vitro culture of metacestodes in the presence of 24 μM mefloquine for a period of 10 days was parasiticidal, as determined by murine bioassays, while treatment with 12 μM was not. Oral application of mefloquine (25 mg/kg of body weight administered twice a week for a period of 8 weeks) in E. multilocularis-infected mice was ineffective in achieving any reduction of parasite weight, whereas treatment with albendazole (200 mg/kg/day) was highly effective. However, when the same mefloquine dosage was applied intraperitoneally, the reduction in parasite weight was similar to the reduction seen with oral albendazole application. Combined application of both drugs did not increase the treatment efficacy. In conclusion, mefloquine represents an interesting drug candidate for the treatment of AE, and these results should be followed up in appropriate in vivo studies.  相似文献   
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The current chemotherapy of alveolar echinococcosis (AE) is based on benzimidazoles such as albendazole and has been shown to be parasitostatic rather than parasiticidal, requiring lifelong duration. Thus, new and more efficient treatment options are urgently needed. By employing a recently validated assay based on the release of functional phosphoglucose isomerase (PGI) from dying parasites, the activities of 26 dicationic compounds and of the (+)- and (−)-erythro-enantiomers of mefloquine were investigated. Initial screening of compounds was performed at 40 μM, and those compounds exhibiting considerable antiparasitic activities were also assessed at lower concentrations. Of the dicationic drugs, DB1127 (a diguanidino compound) with activities comparable to nitazoxanide was further studied. The activity of DB1127 was dose dependent and led to severe structural alterations, as visualized by electron microscopy. The (+)- and (−)-erythro-enantiomers of mefloquine showed similar dose-dependent effects, although higher concentrations of these compounds than of DB1127 were required for metacestode damage. In conclusion, of the drugs investigated here, the diguanidino compound DB1127 represents the most promising compound for further study in appropriate in vivo models for Echinococcus multilocularis infection.  相似文献   
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