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261.
Multiple system atrophy (MSA) is a neurodegenerative disorder of unknown cause. The only case-control study conducted in MSA patients to date suggested a possible contributory genetic component in the pathogenesis of this disorder. The aim of this study was to evaluate a possible overlap between clinically or pathologically well-defined MSA and other conditions with an identified genetic defect causing spinocerebellar degeneration in humans or mutant mice strains. The spinocerebellar ataxia type 1 and 3 genes (SCA1 and SCA3) were analyzed for a pathologic expansion in 80 patients with MSA to evaluate a possible overlap between MSA and SCA1 or SCA3. Weaver mice and lurcher mice are animal models for spinocerebellar degeneration; both share pathologic features with MSA. We sequenced the H5 pore region of the human homologue of the weaver mouse gene, hiGIRK2, in all our patients. In lurcher mice, previous biochemical studies have shown a decreased intracellular response to insulin-like growth factor 1 (IGF-1) in the cerebellar cortex, and we thus investigated the possibility of an allelic association between MSA and the receptor for IGF-1. In addition, we evaluated a possible involvement of the ciliary neurotrophic factor gene (CNTF) and examined the role of HLA-A32 to clarify the conflicting data from previous studies. No changes were detected in any of the analyzed genes. Our studies strongly suggest that MSA is an autonomous syndrome distinct from identified genetic causes for spinocerebellar degeneration.  相似文献   
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The alkali pretreatment of sugar cane bagasse was optimised and compared with an optimised steam (acid) pretreatment. The optimised alkali pretreatment gave an overall sugar yield of 37.4 g sugars per 100 g bagasse accounting for 43.8% of the initial xylan and 64.5% of the glucan. Potential effluent problems were identified with the alkali treatment and several strategies were suggested to minimise them, with liquor recycling showing some promise. The optimised steam (acid) pretreatment gave an overall sugar yield of 55.7 g sugars per 100 g bagasse accounting for 76.5% of the xylan and 89.5% of the glucan. The superiority of the steam (acid) pretreatment over the alkali pretreatment depends on the ability to utilise the xylose produced.  相似文献   
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Declining enrollments in computer science and related fields are a global concern. This issue's column, by Mike Hazas and Rebecca Marsden of Lancaster University in the UK, describes the novel Lancaster Headstart program that uses the excitement of pervasive computing to attract students into computer science.  相似文献   
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Sliced (cut) and exterior (intact) surfaces of restructured cooked roast beef were inoculated with Listeria monocytogenes, treated with cetylpyridinium chloride (CPC; immersion in 500 ml of 1% solution for 1 min), individually vacuum packaged, and stored for 42 days at 0 or 4 degrees C. Noninoculated samples were similarly treated, packaged, and stored to determine effects on quality (color and firmness) and on naturally occurring bacterial populations, including aerobic plate counts and lactic acid bacteria. Immediately after CPC treatment, regardless of inoculation level, L. monocytogenes populations were reduced (P = 0.05) by about 2 log CFU/cm2 on sliced surfaces and by about 4 log CFU/cm2 on exterior surfaces. Throughout 42 days of refrigerated storage (at both 0 and 4 degrees C), L. monocytogenes populations on CPC-treated samples remained lower (P = 0.05) than those of nontreated samples for both surface types. After 42 days of storage at both 0 and 4 degrees C, aerobic plate count and lactic acid bacteria populations of treated samples were 1 to 1.5 log CFU/cm2 lower (P = 0.05) than those of nontreated samples for both surface types. CPC treatment resulted in negligible effects (P > 0.05) on the color (L*, a*, and b* values) of exterior and sliced roast beef surfaces during storage. For both sliced and exterior surfaces, CPC-treated samples were generally less firm than nontreated samples. CPC treatment effectively reduced L. monocytogenes populations on roast beef surfaces and resulted in relatively minor impacts on color and texture attributes. CPC treatment, especially when applied to products prior to slicing, may serve as an effective antimicrobial intervention for ready-to-eat meat products.  相似文献   
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Effectiveness of spray application of potable water wash (WW), 25% (w/v) sodium chloride (NaCl), and 0.1% (v/v) acidified sodium chlorite (ASC) was evaluated against Escherichia coli O157:H7 and Staphylococcus aureus inoculated onto beef briskets. The purpose was to identify antimicrobial treatments which may be applied to beef carcasses and more specifically in kosher meat facilities. Treatments were applied for 10-60 s at pressure of 419 kPa. Water wash, NaCl, and ASC significantly reduced E. coli O157:H7 as compared with the control, although, only ASC resulted in improved removal with increased exposure time. Water wash did not significantly reduce S. aureus counts throughout exposure and NaCl was only effective after 60 s of exposure, while ASC reduced counts throughout exposure. E. coli O157:H7 was twice as sensitive to WW and NaCl as S. aureus in terms of percent reduction in cell count.  相似文献   
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