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Biochemical mechanisms underlying acrylamide induced neurotoxicity were examined using an in vitro model consisting of sagittal slices of rat brain. Incubation of brain slices under oxygen in artificial cerebrospinal fluid containing acrylamide produced a dose and time dependent inhibition of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Lysosomal enzymes, acid phosphatase, N-acetyl glucosaminidase and beta-glucuronidase decreased in a similar manner, while no changes were observed in the activity of Na+K+ATPase, cytochrome c oxidase and lactate dehydrogenase. Incubation of slices with two structurally related compounds, acetamide (a non-neurotoxic amide) and methylene bis-acrylamide (a weak neurotoxin), indicated that acrylamide selectively inhibited GAPDH, enolase and N-acetyl glucosaminidase at low concentration; similar doses of acetamide and methylene bis-acrylamide did not have the same effect on brain slices. Incubation with acrylamide depleted glutathione levels in slices, and the addition of glutathione to the incubation medium prevented acrylamide induced inhibition of GAPDH and lysosomal enzymes. Time dependent inhibition of lysosomal enzymes was also observed in vivo, in the brain and sciatic nerve of rats following a single dose of acrylamide. These results demonstrate that both in vitro and in vivo, lysosomal enzymes are also inhibited following acrylamide exposure. The rat brain slice model exhibits both selectivity and sensitivity towards neurotoxicants and hence, may prove to be an useful in vitro model for the mechanistic evaluation of neurotoxicity. 相似文献
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SB Miranda† O Lupi‡ E Lucas† 《Journal of the European Academy of Dermatology and Venereology》2004,18(5):622-625
Pityriasis rosea (PR) is a relatively common disease although its aetiology has not yet been identified. It occurs worldwide and there is no racial susceptibility factor. It usually affects teenagers and young adults between 10 and 35 years of age. Typical PR is much easier to diagnose than the rare atypical forms. We report a rare case of vesicular PR in a black woman who had vesicular lesions limited to her palms and soles in addition to regular typical lesions. We devised an efficient oral erythromycin treatment for this patient. 相似文献
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An ankylosed tooth can be suitable for obtaining orthodontic anchorage. However, if such a tooth lacks adequate clinical crown height, the anchorage will not be effective. In those situations surgical luxation or restorative crown augmentation is suggested. This case report is about the restorative treatment of an ankylosed, infraoccluded tooth to enhance the anchorage for forced orthodontic eruption of impacted maxillary canines. A crown augmentation in the form of a modified bilayered (sandwich) restoration using GIC, Composite resin and Silver amalgam on left maxillary first molar (26) was successful in sustaining the anchorage for forced eruption and alignment of impacted canines. 相似文献
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The records of two groups of patients (358 schizophrenics and 69 neurotics), attending the community mental health center of the Johns Hopkins Hospital, were reviewed to assess the extent and severity of reported medical problems. Results indicate that 38% of the schizophrenics and 53% of the neurotics report medical problems, but schizophrenics present with serious medical problems more often than do the neurotics. The authors draw attention to the need for properly assessing the severity of these medial problems and for adequately coordinating psychiatric and medical care. Strategies to overcome these difficulties are suggested. 相似文献
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
10.
Selective and differential medium for recovery of Pseudomonas cepacia from the respiratory tracts of patients with cystic fibrosis. 总被引:8,自引:7,他引:8 下载免费PDF全文
D F Welch M J Muszynski C H Pai M J Marcon M M Hribar P H Gilligan J M Matsen P A Ahlin B C Hilman S A Chartrand 《Journal of clinical microbiology》1987,25(9):1730-1734
A selective and differential medium, OFPBL (oxidation-fermentation base supplemented with agar, lactose, and two antimicrobial agents), for the isolation of Pseudomonas cepacia from respiratory specimens of patients with cystic fibrosis was developed and tested. Among 725 specimens submitted from seven centers over a 4- to 6-month period, 58 (8%) yielded P. cepacia on OFPBL; only 19 of these were recovered on MacConkey or sheep blood agar (P less than 0.001). No isolate was recovered on MacConkey or sheep blood agar alone. Ranges of recovery rates among centers were 0 to 15% on OFPBL and 0 to 10% on MacConkey or sheep blood agar. Ninety percent of P. cepacia isolates were detected on OFPBL in less than or equal to 3 days. Other nonfermenters and yeasts isolated on OFPBL were distinguished from P. cepacia by failure to acidify the medium. The new medium was clearly superior to MacConkey and sheep blood agars for the isolation of P. cepacia from the respiratory secretions of patients with cystic fibrosis. 相似文献