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Background Transarterial chemoemobolization (TACE) is commonly used to treat metastatic carcinoid tumors; however, the management of progressive disease is less clear. We sought to determine if patients with disease progression after TACE would benefit from repeat TACE. Methods The records of 27 patients undergoing repeat TACE for radiologic or symptomatic progression after TACE for metastatic carcinoid were reviewed and compared to 122 undergoing first TACE. Overall and progression-free survivals were estimated by the Kaplan–Meier method. Results Mean disease-free interval after first TACE was 11.8 months. Radiologic response was observed in 61% compared to 82% after first TACE (p = 0.058); hormone response in 64% compared to 80% (p = 0.159); and symptomatic response in 77% compared to 92% (p = 0.053). The complication rate after repeat TACE was lower than after first TACE (p = 0.03). Median overall survival was similar after repeat (28.1 months) and first TACE (33.3 months) (p = 0.53). Progression-free survival was shorter after repeat TACE but not significantly so. No factor examined could predict survival after repeat TACE. Conclusion Repeat TACE for patients with hepatic carcinoid metastases failing first TACE or having evidence of disease progression is safe and offers a viable treatment option. Presented at the 48th Annual Meeting of The Society for Surgery of the Alimentary Tract, Washington, DC, May, 2007.  相似文献   
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STUDY OBJECTIVE--A chemical spill from an oil refinery exposed the local community to more than 40,000 lb of highly toxic and corrosive hydrofluoric acid. A community based symptom prevalence study found an association between exposure and physical symptoms: the psychological impact of the disaster and its potential effect on the reporting of physical symptoms is examined here. DESIGN--The study used a population based survey design consisting of two phases: phase I, the exposure phase, and, phase II, the symptom prevalence phase. SUBJECTS--In phase I, information indicative of exposure was collected on 10,811 individuals in a door to door survey of a geographically defined area. In phase II, symptom prevalence information was gathered through in-person interviews with 2509 subjects selected from the phase I census in a sampling scheme that balanced across the exposure categories with regard to age, gender, and predisposition. The refusal rate in both phases was < 5%. MEASUREMENT AND MAIN RESULTS--Stepwise logistic regression analyses were used to assess the relative predictive importance of psychological variables and hydrofluoric acid exposure in explaining the reported physical symptoms two years after the disaster. The findings show a linear relationship between the level of hydrofluoric acid exposure and the degree of psychological stress two years after the accident. High exposure had a long term (more than two years) impact on physical health for some self reported symptoms, even after controlling for the psychological impact. Some physical symptom reports, however, were better explained by psychological status than by exposure to hydrofluoric acid. The physical symptoms for which exposure was the major predictor were those for which the biological plausibility of a relationship with hydrofluoric acid exposure was direct. CONCLUSIONS--Measures of psychological status should be included in symptom studies of health sequelae to man-made disasters so that the physical effects of exposure can be more accurately assessed.  相似文献   
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An accident at an oil refinery in Texas City, Texas, released around 40,000 lb of hydrogen fluoride, exposing the community to the highly toxic and corrosive substance. A population-based epidemiologic study was conducted to evaluate the impact of the accident on the health of the community. Exposure assessment was done using a multipronged approach through a door-to-door survey of 10,811 individuals. A symptom survey resulting in 1994 completed interviews was conducted with a stratified random sample selected from the exposure study database. The sampling was balanced with respect to age, gender, and predisposition across the three ordinal exposure categories. The results show a strong dose relationship (P < 10(-4)) between the exposure and symptoms reported following the accident and 2 years later, most notably breathing and eye symptoms. However, substantial improvement in health was reported over the 2-year period regardless of the level of exposure. Problems of recall bias and behavioral sensitization are considered and it is recognized that the study may have overestimated the effect. It is also recognized that the study may not have completely unraveled the relative importance of exposure and host response in health outcome, since the two were probably conflated in the exposure measure. Nevertheless, the independence of predisposition and reported level of exposure, the magnitude of effect and its consistency, the unmistakable dose response, the large sample size, and the mutual corroboration of various findings make it difficult to dismiss the interpretation that the hydrofluoric acid exposure indeed caused health problems in the community that continued for at least 2 years after the accident.  相似文献   
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Sturge-Weber syndrome is a rare neurocutaneous disorder characterized by a facial nevus flammeus and extensive angiomatous changes involving the leptomeninges, the dura, and vessels of the gray and white matter. Oculodermal melanocytosis is characterized by hyperpigmentation of the facial skin in the distribution of the ophthalmic, maxillary, and occasionally mandibular division of the trigeminal nerve.  相似文献   
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PurposeNoroviruses are common viral agents in acute diarrhea in all age groups worldwide. Norovirus has been classified into 10 genogroups, GI to GX with over 48 genotypes among them the GII.4 genotype has evolved over time with a clear pattern of periodic variant replacement. Immunity is strain or genotype specific with little or no protection conferred across genogroups. The present study was aimed to determine the epidemiology, prevalent genotypes of norovirus in children below five years of age in the Hyderabad region, India.MethodsThe stool samples and clinical data were collected from 458 children below 5 years of age comprising of cases with acute gastroenteritis (n ?= ?366) and a control group (n ?= ?92) admitted to the pediatric ward. All the samples were tested for Norovirus by ELISA and RT-PCR. Sequencing was done for predominant strains.Results10.3% (n ?= ?38) of cases and 3.2% (n ?= ?3) of the control group were found to be Norovirus positive. Predominant genotypes were GII-82.5% followed by GI-12.5%.ConclusionSequencing and Phylogenetic analyses of 20 GII.4 strains was done. All of the isolates are clustered away from published the GII.4 variants thus suggesting the appearance of a new variant.  相似文献   
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We recently reported that a chimeric simian/human immunodeficiency virus (SHIVKU-1) developed in our laboratory caused progressive depletion of CD4+T lymphocytes and AIDS within 6 months of inoculation into pig-tailed macaques (M.nemestrina). None of the pig-tailed macaques showed productive SHIV infection in the central nervous system (CNS). In this report, we show that by further passage of the pathogenic virus in rhesus macaques [M. mulatta], we have derived a new strain of SHIV (SHIVKU-2) that has caused AIDS and productive CNS infection in 3 of 5 rhesus macaques infected with the virus. Productive replication of SHIV in the CNS was clearly shown by high infectivity titers and p27 protein levels in brain homogenates, and in 2 of the 3 rhesus macaques this was associated with disseminated, nodular, demyelinating lesions, including focal multinucleated giant cell reaction, largely confined to the white matter. These findings were reminiscent of HIV-1 associated neurological disease, and our immunohistochemical and in situ hybridization data indicated that the neuropathological lesions were associated with the presence of SHIV-specific viral antigens and nucleic acid respectively. However, the concomitant reactivation of opportunistic infections in these macaques suggested that such pathogens may have influenced the replication of SHIV in the CNS, or modified the neuropathological sequelae of SHIV infection in the rhesus species, but not in pig-tailed macaques. Our findings in the two species of macaques highlight the complexities of lentiviral neuropathogenesis, the precise mechanisms of which are still elusive.  相似文献   
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Ghrelin, a recently discovered peptide isolated from the gastric corpus mucosa, is believed to be important in the regulation of growth hormone secretion and has been shown to increase appetite and food intake as well. It may also have other gastrointestinal and cardiac functions. Because a cell of origin for ghrelin has not been convincingly identified in the gastric mucosa thus far, we studied the immunohistochemical expression of ghrelin in proliferative lesions of the enterochromaffin-like (ECL) cells—a cell that is not only exclusively confined to the gastric corpus mucosa but is its dominant endocrine cell type as well. Formalin-fixed, paraffin embedded tissues from three cases of gastric ECL cell hyperplasia and five ECL carcinoids (three with coexisting foci of diffuse, linear, and micronodular hyperplasia) were immunohistochemically stained for ghrelin, using a commercially available antibody. The Sevier-Munger stain for ECL cells and immunohistochemical stains for chromogranin, gastrin, serotonin, somatostatin, and vesicular monoamine transporter-2 (VMAT-2) were performed on parallel sections for correlation with the ghrelin staining results. All ECL cell carcinoids and hyperplastic lesions were positive for both the Sevier-Munger and the immunohistochemical stains for chromogranin and VMAT-2. Immunoreactivity for ghrelin was seen in 4/5 ECL carcinoids, all cases of ECL cell hyperplasia, as well as in all areas with linear and micronodular hyperplasia adjacent to the ECL cell carcinoids. In each instance, such staining was confined to the Sevier-Munger, and VMAT-2 positive cells only. Our findings indicate that the ECL cells are either the ghrelin-producing cells of the gastric mucosa or acquire the capability to synthesize ghrelin during proliferative states encompassing the entire hyperplasia to neoplasia spectrum. In view of the orexigenic and other known actions of ghrelin, the functional and/or biologic significance of ghrelin production in such ECL cell proliferations needs to be investigated further.  相似文献   
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