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991.
OBJECTIVE: To provide an overview of hepatitis B infection in Brazil overall, in the South of Brazil, and in the state of Santa Catarina (in southeastern Brazil) for the period of 1996 through 2002, taking into consideration such epidemiological aspects as age and sex. Source of data: Data were obtained through a literature review and by consulting with Brazil's National Health Foundation and with Santa Catarina's Department of Epidemiological Surveillance. RESULTS: In Brazil, from 1996 through 2000, hepatitis B was the second most prevalent type of viral hepatitis (25%), with hepatitis A leading in terms of the proportion of cases (43%). In Santa Catarina there was a predominance of hepatitis B in relation to other types of hepatitis from 1997 through 2001. In both Brazil and Santa Catarina there was a larger number of cases among males than among females. In terms of age, the highest incidence was found among those 20 to 49 years old in Santa Catarina and among those over 30 for Brazil overall. The South of Brazil was the country's region with the highest incidence of hepatitis B from 1997 through 1999. In Santa Catarina the largest number of cases from 1996 through 2002 occurred in the southern part of the state, followed by the northeastern and far western sections of the state. CONCLUSIONS: The number of cases of hepatitis B is still growing in Brazil, and it is important to consider that underreporting may have affected the results described in this study. Throughout Brazil, vaccination should be extended to include adolescents in regions that have a moderate to high incidence of hepatitis B.  相似文献   
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A 1.5-year-old girl presented with a peripheral iris mass. When the girl was 3 years old, the lesion was excised after it had manifested significant growth. A stalk of fibrovascular tissue was noted to extend from the lesion to the optic disc. Histopathologically, the tumor was a well-circumscribed, pigmented ciliary body adenoma. Electron microscopy revealed characteristic neuroepithelial melanosomes, distinct from those of choroidal melanocytes, and occasional annulate lamellae. A fibrovascular membrane extended over the tumor surface and was adherent to lens capsule. The association of this adenoma with a persistent stalk of primary vitreous indicates a congenital origin of this tumor. Both adenoma and adenocarcinoma of the pigmented and nonpigmented ciliary epithelium tend to be disorders of adults. The authors report the youngest presentation of a pigment epithelium adenoma, the only well-documented case associated with persistent hyperplastic primary vitreous, and the only documentation of annulate lamellae in a ciliary body tumor.  相似文献   
994.
Patients with malignant tumors of the pelvis who cannot be cured surgically often are treated with radiation after surgery. A devastating side effect of this treatment is radiation-associated small bowel injury (RASBI). The purpose of this study was to test the hypothesis that removal of the small bowel from the radiation field would protect it against RASBI. Twenty cebus monkeys underwent low anterior resection. In 10 animals an absorbable polyglycolic acid (PGA) mesh was sewn circumferentially around the interior of the abdominal cavity as a supporting apron, which prevented the small bowel's descent into the pelvis. The other 10 monkeys did not receive the mesh. All animals received 2000 rads by linear acceleration in a single dose. Twenty-four-hour stool fat, serum vitamin B12, and other serum values were obtained during the study. Animals were sacrificed after 1, 2, 3, 6, and 12 months, and the small bowel and rectum were examined histologically in a blind manner. Two monkeys who did not undergo surgery, or exposure to radiation served as controls. At all sacrifice periods, the animals with PGA mesh slings demonstrated normal small bowel function and histologic structure. Animals without mesh slings had abnormal stool and blood values at 1 month, and by 2 months all had died of small bowel necrosis. The animals that received the slings had no evidence of infection or obstruction, and by 6 months all evidence of the mesh was gone. Support of the small bowel out of the pelvis by an absorbable PGA mesh sling protects against RASBI and is without apparent complications.  相似文献   
995.
Cystadenocarcinoma of the rete testis   总被引:1,自引:0,他引:1  
We report a rare case of primary adenocarcinoma of the rete testis. The stage A lesion was managed successfully with orchiectomy and retroperitoneal lymph node dissection. The histopathological features, treatment and prognosis of this unusual malignancy are reviewed.  相似文献   
996.
Studies examining the interaction of platelets with exposed subendothelium in vivo have reported conflicting results. To examine possible explanations for the apparently discrepant findings, we measured the platelet reactivity of subendothelium prepared by a number of methods both in vivo and in vitro. In addition, we examined the possibility that 13-hydroxyoctadecadinoic acid (13-HODE), an endothelial cell-derived chemorepellant, modulates the reactivity of the subendothelium to platelets. In vivo, the subendothelium of segments of rabbit carotid arteries was exposed by removing the endothelial cells by air perfusion or by balloon catheter stripping. Platelet accumulation onto the de-endothelialized segments was assessed by 3H-radioactivity uptake, using 3H-adenine-labelled platelets, and by scanning electron microscopy. In vitro, 3H-adenine-labelled platelet adhesion was measured onto plain plastic discs and onto plastic discs coated with the following purified basement membrane components: collagens type I, III, IV, V, laminin, or fibronectin. In addition, 3H-adenine-labelled platelet adhesion was measured onto plastic discs covered with human endothelial cells or onto the basement membrane underlying the endothelial cells. In vivo, there was marked 3H-platelet accumulation onto the balloon catheter carotid arteries one hour after injury. In contrast, there was no platelet accumulation onto the subendothelium of carotid arteries de-endothelialized by air perfusion. These differences were confirmed by scanning electron microscopy. Transmission electron microscopic examination demonstrated that the extracellular matrix was intact following the air perfusion injury whereas the majority of it was removed by the balloon catheter injury.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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999.
Sensory disturbances such as olfactory or visual dysfunctions are common in Parkinson’s disease (PD). A possible relationship between distorted colour discrimination and the nigrostriatal dopamine deficit is still a matter of debate. We examined 31 de novo Parkinsonian patients with [123I]β-CIT single photon emission tomography (SPECT). We used a single-head γ-camera and calculated the binding ratio striatum/cerebellum (specific/nonspecific binding) of [123I]β-CIT uptake. On the same day, we performed the Farnsworth-Munsell 100 Hue Test (FMT) in these patients and estimated the total error score, in order to investigate abnormalities of colour vision. Parkinsonian patients’ total error score was higher compared with an age- and sex-matched control group (P = < 0.0001), whereas disability scores of the Hoehn and Yahr scale (P = 0.019, Spearman r = 0.419) and the Unified Parkinson’s Disease Rating Scale (P = 0.039, Spearman r = 0.373) correlated with total error score. No significant association appeared between total error score (Spearman r = –0.119, P = 0.525) and [123I]β-CIT-SPECT ratio. Thus both total error scores of the FMT and [123I]β-CIT-SPECT binding ratios have been found to reflect the severity of PD. However, only [123I]β-CIT SPECT reflects degeneration of dopaminergic neurons of the basal ganglia, but does not reflect alterations of the visual system and/or extranigral lesions in PD. From our results, we speculate that FMT may be a valuable clinical method to measure extranigral lesions of the visual system in PD. Received: 1 September 1997 Received in revised form: 27 February 1998 Accepted: 20 March 1998  相似文献   
1000.
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