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Objective: To compare four vancomycin-containing agar media for the isolation of glycopeptide-resistant enterococci (GRE) from clinical fecal specimens: kanamycin-aesculin-azide (KAA) agar; bile-aesculin-polymixin (BAP) agar; aztreonam-amphotericin blood (CBAA) agar; and neomycin blood (CBN) agar.
Methods: Fecal specimens from 125 patients were inoculated onto each medium. Media were examined for enterococci after incubation for up to 48 h. Enterococci were identified to species level, and glycopeptide phenotypes were determined by measuring minimum inhibitory concentrations of vancomycin and teicoplanin.
Results: GRE were isolated from 44/125 samples. Enterococcus faecalis and Enterococcus faecium isolates, expressing glycopeptide resistance of the VanA or VanB phenotypes, were recovered from 27/33 (82%) specimens on BAP medium, 26/33 (79%) on KAA medium, and 21/33 (64%) on CBN and CBAA media. Enterococcus gallinarum and Enterococcus casseliflavus isolates expressing low-level glycopeptide resistance (VanC phenotype) were recovered from 14/15 (93%) specimens on CBAA medium, 7/15 (47%) on KAA and CBN media, and 6/15 (40%) on BAP medium.
Conclusions: The media tested in this study, with the exception of CBN medium, detected at least 75% of patients colonized by GRE. Further development of BAP, CBAA and KAA media is warranted to improve growth and selectivity.  相似文献   
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Five patients with HIV associated cutaneous cryptococcal infection are reported.  相似文献   
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Influence of nanoporous alumina membranes on long-term osteoblast response   总被引:8,自引:0,他引:8  
A major goal of bone tissue engineering is to design better scaffold configuration and materials to better control osteoblast behavior. Nanoporous architecture has been shown to significantly affect cellular response. In this work, nanoporous alumina membranes were fabricated by a two-step anodization method to investigate bone cell response. Osteoblasts were seeded on nanoporous alumina membranes to investigate both short-term adhesion and proliferation and long-term functionality and matrix production. Cell adhesion and proliferation were characterized using a standard MTT assay and cell counting. The total protein content was measured after cell lysis using the BCA assay. Matrix production was characterized in terms of surface concentrations of calcium and phosphorous, components of bone matrix, using X-ray photoelectron spectroscopy (XPS). The results from nanoporous alumina membranes were compared with those of amorphous alumina, aluminum, commercially available ANOPORE and glass. Results indicate improved osteoblast adhesion and proliferation and increased matrix production after 4 weeks of study.  相似文献   
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Mannophosphoinositides isolated from mycobacterial cells were found to induce both humoral and cell-mediated immune responses in mice when injected as mannoside-methylated bovine serum albumin (MBSA) complexes. Immunization of mice with mannoside-MBSA complexes elicited significant protection against challenge with LD50 dose of M. tuberculosis H37Rv as revealed by high survival rate, low values of root-specific lung weight, lung densities and colony forming units recovered from lung, liver and spleen, compared to the nonimmunized group. These observations were further substantiated by histopathological studies. The protective immunity elicited by mannoside-MBSA complexes against challenge with M. tuberculosis H37Rv was mediated by the cooperation of T-B cells, as shown by the passive transfer of immune cells/sera into syngeneic sublethally irradiated recipient mice.  相似文献   
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Primary myeloid sarcoma of the testicle with t(15;17)   总被引:1,自引:0,他引:1  
The first case of acute promyelocytic leukemia presenting as a solitary testicular mass (myeloid sarcoma) that relapsed in the contralateral testicle is described. The neoplastic cells strongly expressed chloroacetate esterase, myeloperoxidase, CD33, CD43, and weakly, CD117. The presence of many azurophil granules and Auer rods was detected by electron microscopy. Translocation (15;17)(q22;q21.1) was revealed by cytogenetics and was verified by fluorescence in situ hybridization. Contralateral testicle is a favorite site for recurrence in a subset of testicular myeloid sarcomas. Subclassification of all cases of myeloid sarcoma ought to be attempted.  相似文献   
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We describe the emergence of a nephropathogenic avian infectious bronchitis virus (IBV) with a novel genotype in India. The Indian IBV isolate exhibited a relatively high degree of sequence divergence with reference strains. The highest homology was observed with strain 6/82 (68%) and the least homology with strain Mex/1765/99 (34.3%).  相似文献   
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A competitive type-specific enzyme-linked immunosorbent assay (ELISA) for herpes simplex virus type 2 (HSV-2) antibody was developed using an infected cell antigen and a monoclonal antibody to glycoprotein G-2. This assay has been validated for use for epidemiological studies using a large panel of sera collected in rural Uganda and a panel of 143 sera characterised previously by Western blotting, the 'gold standard' for HSV type-specific serology. This evaluation was found to have a sensitivity of 96% and a specificity of 91% in comparison with Western blot on 143 sera from clinic patients. The ELISA had a sensitivity of 93% and a specificity of 91% in comparison with Western blot on 495 sera collected in Uganda. The assay showed good reproducibility and a low percentage of sera gave equivocal results, indicating its suitability for epidemiological studies.  相似文献   
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