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101.
The preparation of N-methylaniline in two various processes: alkylation of aniline with methanol and hydroalkylation of nitrobenzene with methanol has been studied. Bifunctional molecular sieves containing metal copper as the hydrogenating component and zeolites BEA, MOR, MFI, FAU (Y) and mesoporous material MCM-41 as an alkylating component were used as catalysts. It has been shown that the modification of samples with copper nitrate increases the number of Lewis acid sites and decreases the number of Brønsted acid sites as copper embeds into cation exchange positions. It has been determined that the catalyst modification with copper increases the activity and enhances the selectivity towards N-alkylated products.  相似文献   
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Congenital lactase deficiency (CLD) is an autosomal recessive, gastrointestinal disorder characterized by watery diarrhea starting during the first 1-10 d of life, in infants fed lactose-containing milks. Since 1966, 42 patients have been diagnosed in Finland. CLD is the most severe form of lactase deficiency, with an almost total lack of lactase-phlorizin hydrolase (LPH) activity on jejunal biopsy. In adult-type hypolactasia, the most common genetic enzyme deficiency in humans, this enzyme activity is reduced to 5%-10%. Although the activity of intestinal LPH has been found to be greatly reduced in both forms, the molecular pathogenesis of lactase deficiencies is unknown. On the basis of the initial candidate-gene approach, we assigned the CLD locus to an 8-cM interval on chromosome 2q21 in 19 Finnish families. At the closest marker locus, a specific allele 2 was present in 92% of disease alleles. On the basis of a genealogical study, the CLD mutation was found to be enriched in sparsely populated eastern and northern Finland, because of a founder effect. The results of both the genealogical study and the haplotype analysis indicate that one major mutation in a novel gene causes CLD in the Finnish population. Consequently, the critical region could be restricted further, to an approximately 350-kb interval, by ancient-haplotype and linkage-disequilibrium analyses. Surprisingly, the LPH gene was shown to lie outside the critical CLD region, excluding it as a causative gene for CLD. The LPH locus was found to reside >2 Mb from the critical CLD region.  相似文献   
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PURPOSE: To investigate the efficacy and safety of oral ondansetron in the control of cisplatin-induced delayed emesis in patients who do not require rescue antiemetic therapy for acute emesis. PATIENTS AND METHODS: Five hundred thirty-eight chemotherapy-naive patients who received cisplatin chemotherapy (> or = 70 mg/m2), and who were not rescued for acute emesis, were eligible to be randomized to receive one of the three oral regimens to control delayed emesis. Group I received placebo on days 2 to 6; group II received ondansetron 8 mg twice daily on days 2 and 3 and placebo on days 4 to 6; group III received ondansetron 8 mg twice daily on days 2 to 6. All patients received intravenous ondansetron (0.15 mg/kg every 4 hours for three doses) for the control of acute emesis on day 1. The number of emetic episodes on days 2 and 3 combined (days 2/3, when incidence and severity of delayed emesis were expected to be greatest) was considered the primary measure of efficacy. RESULTS: Patients who received odansetron had significantly fewer emetic episodes on days 2/3, 4, and 5 than those who received placebo (P < or = .002 on each day). Additionally, significantly more patients who received ondansetron had a complete plus major response (C+MR; < or = two two emetic episodes) than those who received placebo on days 2/3 (56% v 37%, P = .001), 4 (94% v 85%, P = .005), and 5 (98% v 88%, P = .006). Patients who received ondansetron had significantly less nausea on day 2/3 when day-1 nausea was used as the baseline score (P = .025). Patients who received ondansetron also had significantly less nausea on day 4 (P = .042) and the results approached significance on day 5 (P = .066). CONCLUSION: Oral ondansetron had a significant effect in the control of cisplatin-induced delayed emesis and nausea in patients who had not required rescue antiemetics during the acute emesis period. The control of delayed nausea and vomiting was most notable in the immediate 2 days following cisplatin administration, with the clinical difference narrowing between the two treatment arms on subsequent days.  相似文献   
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Research has shown that the activation and application of a significant-other representation to a new person, or transference, occurs in everyday social perception (S. M. Andersen & A. Baum, 1994; S. M. Andersen & S. W. Cole, 1990). Using a combined idiographic and nomothetic experimental paradigm, two studies examined the role of chronic accessibility of significant-other representations in transference. After learning about 4 fictional people, 1 of whom resembled a significant other, participants' recognition memory was assessed. Both studies showed greater false-positive memory in the significant-other condition, relative to control, even in the absence of priming. Study 2 showed that although the effect was greater when the significant-other representation was concretely applicable to the target information, it occurred even when no such applicability was present. Results implicate the chronic accessibility of significant-other representations in transference.  相似文献   
107.
Two intestinal spirochete isolates obtained from chickens with diarrhea were examined by electron microscopy, biochemical tests, rRNA gene restriction pattern analysis, and multilocus enzyme electrophoresis. One isolate (strain 91-1207/C1) was pathogenicity tested in vivo in chickens. The chicken spirochetes were morphologically indistinguishable from Serpulina innocens and Serpulina hyodysenteriae and phenotypically similar to S. innocens. However, the chicken spirochetes could be distinguished from S. innocens, S. hyodysenteriae, and other swine intestinal spirochetes by rRNA gene restriction pattern analysis and multilocus enzyme electrophoresis. In pathogenicity tests in 1-day-old chicks and 14-month-old hens, chicken spirochete 91-1207/C1 produced pale-yellow, watery cecal contents and mild lymphocytic typhlitis. These findings support the conclusion that avian intestinal spirochetes can be pathogenic to commercial poultry and that the microorganisms are different from intestinal spirochetes that infect pigs.  相似文献   
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The authors proved that animals having higher natural antioxidant activity and lower intensity of lipid peroxidation are more resistant to fibrogenic effects of quartz. The peritoneal macrophages obtained from those animals show higher resistance to quartz exposure "in vitro". Parameters characterizing antioxidant system should be included into a group of indexes describing propensity to silicosis.  相似文献   
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