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991.

Background

Cryptococcus neoformans is encapsulated yeast which causes life-threatening infections in up to 40% of AIDS patients in Africa.

Objective

To investigate the prevalence of cryptococcosis among HIV infected patients in Yaounde.

Methods

In a hospital-based surveillance study of cryptococcosis, the colonization of Cerebrospinal Fluid (CSF), urine and blood sample by C. neoformans was evaluated by direct microscopic examination and culture techniques. Data obtained were then analyzed based on the medical records of the patients.

Results

Among the105 patients sampled for the study, the CD4 counts varied between 31 and 304 lymphocytes/mm3. Direct specimens examination (n= 294) in India ink preparations revealed polysaccharide capsule in 25 (8.5%) of the samples. Upon culture, 29 (9.86 %) samples were positive of C. neoformans (23 from the CSFs and 6 from the urine). All the positive samples were obtained from patients who were not on Antiretroviral Therapy (ART). Meningo-encephalitis symptoms were observed in 13 patients with C. neoformans in CSFs.

Conclusion

This study reveals that cryptococcosis is rife in AIDS patients in Yaounde. Therefore, to minimize the death toll, we recommend that its routine check should be integrated in the management of HIV/AIDS patients.  相似文献   
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Abstract: Background: Abrikossoff or granular cell tumour (GCT) is a relatively rare neoplasia, benign in most of the cases. It may occur in any part of the human body, but it has an oral location in 70% of the cases. Its origin has been discussed for decades, and it is not yet definitively determined. Immunohistochemical techniques suggest its origin in the Schwann cells, while more recent studies with new markers indicate an origin related to neuroendocrine cells. Objective: Contribute to the clarification of histogenesis of oral Abrikossoff tumour studying immunohistochemical marking of 11 oral Brazilian cases. Materials and methods: Samples of tissues from the oral mucosa, tongue and lips placed in paraffin blocks, from eleven patients with a histopathological diagnosis of benign GCT were studied. Four different anti‐serums (S‐100, vimentin, PGP9.5 and ENE) were used for immunoperoxydase technique. Results: A clear positivity for S‐100 protein and vimentin was observed, with markers indicating origin from the Schwann cells. Less intense positivity was found in some cases, for ENE and PGP9.5, which suggests a neuroendocrine origin. Conclusions: The results obtained suggest an origin from Schwann cells, but also arise the possibility of neuroendocrine origin. New methods and more specific immunohistochemical markers are needed to elucidate the origin of the Abrikossoff tumour.  相似文献   
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P-矩阵分光光度法同时测定复方降压片中六种组分的含量   总被引:3,自引:0,他引:3  
徐建平  相秉仁  安登魁 《药学学报》1989,24(11):853-858
本文应用P-矩阵分光光度法同时测定十组分的复方降压片中维生素B1、维生素B6、利眠宁、盐酸异丙嗪、硫酸双肼肽嗪及氢氯噻嗪等六种组分的含量,并应用“条件数”原理来选择最佳测定波长,同时就实验误差,测定点数、“条件数”、组分浓度对处方量的偏差等因素对该法计算结果的影响进行了较为深入的探讨。被测组分的平均回收率均在97~10?%范围之内,变异系数(CV%)均小于或等于9.5(n=11)。  相似文献   
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In 200 consecutive patients undergoing percutaneous transluminal renal angioplasty (PTRA), a significant increase in primary success rate (P less than .02) and a concomitant decrease in complications were noted in the second 100 patients. The primary success rate increased from 93% to 97%, and the incidence of total complications fell from 20% to 13%. The incidence of complications requiring surgery fell from 5% to 2%, and the incidence of renal failure declined from 10% to 5% of the patient population. Variables that contributed to improvement in the procedure included new approaches to crossing arterial stenoses, increased use of digital imaging, less contrast material used in each case, better hydration of patients, and increased use of vascular sheaths at the puncture site.  相似文献   
1000.
Stenosis of individual pulmonary veins: radiologic findings   总被引:1,自引:0,他引:1  
Congenital stenosis of individual pulmonary veins is uncommon. Of the 49 cases reported, four were seen at the IWK Hospital for Children and are reported here. Plain radiographs show a shift of the heart toward the side of major involvement, Kerley B lines, fluid in the fissures, and interstitial edema of the affected lobes. These findings, while subtle, should nevertheless suggest stenosis. Technetium-99m macro-aggregate lung perfusion scans show absence of or diminished perfusion of the affected lobes. The diagnosis can usually be confirmed with angiography. Congenital stenosis of individual pulmonary veins should be considered in children with repeated pulmonary infections, dyspnea, failure to thrive, hemoptysis, or unexplained pulmonary hypertension.  相似文献   
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