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排序方式: 共有4871条查询结果,搜索用时 15 毫秒
971.
Roberto Berni Canani Naseer Sangwan Andrew T Stefka Rita Nocerino Lorella Paparo Rosita Aitoro Antonio Calignano Aly A Khan Jack A Gilbert Cathryn R Nagler 《The ISME journal》2016,10(3):742-750
Dietary intervention with extensively hydrolyzed casein formula supplemented with Lactobacillus rhamnosus GG (EHCF+LGG) accelerates tolerance acquisition in infants with cow''s milk allergy (CMA). We examined whether this effect is attributable, at least in part, to an influence on the gut microbiota. Fecal samples from healthy controls (n=20) and from CMA infants (n=19) before and after treatment with EHCF with (n=12) and without (n=7) supplementation with LGG were compared by 16S rRNA-based operational taxonomic unit clustering and oligotyping. Differential feature selection and generalized linear model fitting revealed that the CMA infants have a diverse gut microbial community structure dominated by Lachnospiraceae (20.5±9.7%) and Ruminococcaceae (16.2±9.1%). Blautia, Roseburia and Coprococcus were significantly enriched following treatment with EHCF and LGG, but only one genus, Oscillospira, was significantly different between infants that became tolerant and those that remained allergic. However, most tolerant infants showed a significant increase in fecal butyrate levels, and those taxa that were significantly enriched in these samples, Blautia and Roseburia, exhibited specific strain-level demarcations between tolerant and allergic infants. Our data suggest that EHCF+LGG promotes tolerance in infants with CMA, in part, by influencing the strain-level bacterial community structure of the infant gut. 相似文献
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975.
Eugen S. Ganger Rita U. Mueller Samuel Goldenberg Carlos Morel 《Molecular biology reports》1975,2(4):343-349
Duck- and rabbit globin messenger ribonucleoprotein complexes isolated by oligo(dT) cellulose chromatography reveal an identical protein pattern—two main proteins of molecular weights of 73000 and 49000 daltons and minor components—whether the complexes have been liberated from polyribosomes with the EDTA-or the puromycin-high-salt method. In the globin messenger ribonucleoprotein particles of both species predominantly the protein with a molecular weight of 73000 daltons is attached to poly(A)-containing regions of the messenger RNAs. 相似文献
976.
Beatrice Lanzrein Masashi Hashimoto Vinka Parmakovich Koji Nakanishi Rita Wilhelm Martin Lüscher 《Life sciences》1975,16(8):1271-1284
By the combined use of high-pressure liquid chromatography, bioassay and gas chromatography/ chemical ionization/mass spectrometry we were able to isolate and identify the three known natural juvenile hormones (JHs) from haemolymph extracts of larval and adult females of the cockroach . This is the first demonstration of the simultaneous occurrence of the three JHs in the same insect and the first time JH I and II have been identified in a hemimetabolous insect. Quantitative investigations show that the composition of the three JHs is different at different developmental stages. The haemolymph of larvae contains a high percentage of JH I and II, whereas the haemolymph of adult females in the oocyte maturation stage contains mostly JH III. This suggests more juvenilizing functions for JH I and II and more gonadotropic functions for JH III. 相似文献
977.
Extractable Lipids of Gram-Negative Marine Bacteria: Phospholipid Composition 总被引:15,自引:0,他引:15
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Phospholipid compositions of 20 strains of marine and estuarine bacteria were determined. Results showed that phospholipids of marine bacteria differed very little from those of nonmarine organisms with phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol being the predominant phospholipids in all strains examined. Lyso-phosphatidylethanolamine occurred in significant quantities among a number of the marine bacteria, and two of the isolates contained significant quantities of poly-beta-hydroxybutyrate. Effects of age and growth temperature on the phospholipid composition were also investigated. It is suggested that phylogenetic relationships among bacteria may be correlated with phospholipid composition. 相似文献
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When female mice were given a dose of 20 × 10 rad X-rays, the specific locus mutation rate among offspring conceived up to 7 weeks after the end of treatment was 1/39887 or 0.18·10−7/rad/locus, whereas when the same total dose of 200 rad was given in a single exposure the mutation rate was 9/34813 or 1.85·1010−7/rad/locus. The lower mutation rate after the 20 × 10 rad dose was obtained whether the total of 200 rad was given over a period of 5 days or 4 weeks, and if only young conceived in the first 20 days, rather than 7 weeks, were considered. It is suggested that each 10 rad fraction had the same small effect, and hence that these results confirm and extend Russell's previous finding that the dose-response relationship for specific locus mutations in females is curved. 相似文献
980.
Phytochrome-induced increases in enzyme activities for phenylalanine ammonia-lyase (EC 4.3.1.5) and chalcone isomerase (EC 5.5.1.6), and in amounts of the related end products, anthocyanin and the flavonol, quercetin, were measured in cotyledons of mustard (Sinapis alba L.). There was no correlation between the activities of these enzymes and the rate of anthocyanin accumulation; however, some correlation was found with the quercetin accumulation rate. Since anthocyanin and flavonol accumulation is spatially separated in mustard (flavonols in the upper epidermis, anthocyanin in the lower epidermis), it was possible to measure anthocyanin-associated phenylalanine ammonia-lyase independently. This activity correlated well with the accumulation rate for anthocyanin during the first few hours after induction. The phytochrome effect on anthocyanin formation differed from that on quercetin formation: anthocyanin was strongly induced by continuous far-red light and by both continuous red light and red light pulses, whereas quercetin was only effectively induced by continuous far-red light.Abbreviations CHI
chalcone isomerase
- PAL
phenylalanine ammonia-lyase 相似文献