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171.
An investigational drug (2-picoline, 6-amino-4-nitro-, 1-oxide) was evaluated to characterize the anti-coccidial spectrum of the compound. Two concentrations of the drug (125 and 250 ppm) were evaluated for bioactivity; weight gain, survival, dropping, and lesion scores were the response variables utilized to ascertain activity. The activities of the picoline derivative were compared with monensin, maduramicin, and a narasin/nicarbazin (1:1) combination. The investigational drug had significant activity against Eimeria tenella and Eimeria necatrix, and the 250-ppm level was significantly more active than 125 ppm. At 250 ppm, the E. tenella activity of the picoline derivative was comparable to both monensin (120 ppm) and the 50-ppm narasin/nicarbazin combination, significantly less effective than maduramicin (6 ppm), and significantly more efficacious than 30 ppm narasin/nicarbazin. At the same level (250 ppm), the picoline derivative had significantly less E. necatrix activity than monensin (120 ppm), maduramicin (6 ppm), and narasin/nicarbazin (50 ppm), and significantly greater activity than 30 ppm narasin/nicarbazin. At best, only extremely weak Eimeria acervulina, Eimeria brunetti, and Eimeria maxima activities were noted with the investigational drug; higher concentrations of the picoline derivative may achieve greater anti-coccidial activity against these species. The efficacy of narasin/nicarbazin compared favorably with monensin and maduramicin; the 50-ppm level of the combination appeared significantly more efficacious than 30-ppm.  相似文献   
172.
A bacterium that was able to tolerate and reduce as high as 50 mM of sodium molybdate to molybdenum blue has been isolated from a metal recycling ground. The isolate was tentatively identified as Serratia sp. strain Dr.Y8 based on the carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. ANOVA analysis showed that isolate Dr.Y8 produced significantly higher (P < 0.05) amount of Mo-blue with 3, 5.1 and 11.3 times more molybdenum blue than previously isolated molybdenum reducers such as Serratia marcescens strain Dr.Y6, E. coli K12 and E. cloacae strain 48, respectively. Its molybdate reduction characteristics were studied in this work. Electron donor sources such as sucrose, mannitol, fructose, glucose and starch supported molybdate reduction. The optimum phosphate, pH and temperature that supported molybdate reduction were 5 mM, pH 6.0 and 37°C, respectively. The molybdenum blue produced from cellular reduction exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium, silver, copper and mercury resulted in approximately 61, 57, 80, and 69% inhibition of the molybdenum-reducing activity at 1 mM, respectively. The reduction characteristics of strain Dr.Y8 suggest that it would be useful in future molybdenum bioremediation.  相似文献   
173.
The differences between the composition of volatile substances in two specimens of dry smoked sausages produced using a standard and experimental (a mixture of propionic acid bacteria and bifidobacteria) cultures were studied by capillary gas chromatography. It was found that the experimental starter culture intensified the flavor-formation processes as compared with the standard culture. The experimental specimen had richer qualitative and quantitative compositions and displayed more intensive aroma and flavor. The contents of lactones and volatile terpenoids in the experimental specimen were much higher than in the control. The organoleptic characteristics of experimental dry smoked sausage specimen were considerably better.  相似文献   
174.
Many studies have examined the association between the FABP2 (rs1799883) Ala54Thr gene polymorphism and type 2 diabetes mellitus risk (T2DM) in various populations, but their results have been inconsistent. To assess this relationship more precisely, A HuGE review and meta‐analysis were performed. The PubMed and CNKI database was searched for case‐control studies published up to April 2014. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Ultimately, 13 studies, comprising 2020 T2DM cases and 2910 controls were included. Overall, for the Thr carriers (Ala/Thr and Thr/Thr) versus the wild‐type homozygotes (Ala/Ala), the pooled OR was 1.18 (95% CI = 1.04–1.34, P = 0.062 for heterogeneity), for Thr/Thr versus Ala/Ala the pooled OR was 1.17 (95% CI = 1.05–1.41 P = 0.087 for heterogeneity). In the stratified analysis by ethnicity, the significantly risks were found among Asians but not Caucasians. This meta‐analysis suggests that the FABP2 (rs1799883) Ala54Thr polymorphisms are associated with increased susceptibility to T2DM risk among Asians but not Caucasians.  相似文献   
175.
Escherichia coli strains MC4100 (parent) and a mutant strain derived from this (IC007) were evaluated for their ability to produce H2 and organic acids (OAs) via fermentation. Following growth, each strain was coated with Pd(0) via bioreduction of Pd(II). Dried, sintered Pd-biomaterials (‘Bio-Pd’) were tested as anodes in a proton exchange membrane (PEM) fuel cell for their ability to generate electricity from H2. Both strains produced hydrogen and OAs but ‘palladised’ cells of strain IC007 (Bio-PdIC007) produced ~threefold more power as compared to Bio-PdMC4100 (56 and 18 mW respectively). The power output used, for comparison, commercial Pd(0) powder and Bio-Pd made from Desulfovibrio desulfuricans, was ~100 mW. The implications of these findings for an integrated energy generating process are discussed.  相似文献   
176.
Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this disease.  相似文献   
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179.
During recent years the nuclear localization of glutathione has been confirmed and this fraction has been quantitatively determined. The nuclear GSH and the enzymes of its metabolism realize independent and important functions. They considerably differ from functions of hyaloplasmic and mitochondrial GSH. Glutathione interacts with regulatory pathways, involved into signal transmission into the nucleus.  相似文献   
180.
Cyclic nucleotide phosphodiesterase from wheat sprouts was isolated and partially purified. The molecular weight of the enzyme is about 83 000. The enzyme activity sharply rises as the inhibiting factors present in the homogenate are separated. The pH optimum of the enzymatic reaction is 4,8. Divalent cations (Mg2+, Mn2+, Cu2+) within the concentration range of 1--5 mM and complexons (EDTA, EGTA) at the concentration of 1 mM do not affect the PDE activity. The temperature optimum for the reaction is 60 degrees. The enzyme hydrolyzes 3' : 5'-AMP, 3' : 5'-GMP and 2':3'-AMP. The Km value for cAMP is 4 . 10(-3) M. The enzyme activity is inhibited by chemical agents possessing the fungicide activity, the strongest effect being exerted by anylate.  相似文献   
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