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51.
Natural sources,i.e. fungal strains and species producing ergot alkaloids (EA), are surveyed together with the chemical structures of EA and a
list of new natural EA discovered in the last three decades. Other topics include new efficient chromatographic methods (HPLC)
for the separation and isolation of new natural EA and also immunological methods of EA detection. 相似文献
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The estimate of food consumption by the bluegill sunfish ( Lepomis macrochirus ) population of Wyland Lake, Indiana, was examined with reference to recent research on the length of the growing season and the effect of body weight, ration and activity on growth efficiency. Growth efficiency was measured in the laboratory in terms of protein, comparing nitrogen assimilated with nitrogen accumulated over a period of about 30 days.
The revised consumption of protein was 134.9kg (or 1407kg live weight of aquatic organisms, 444 kg/ha) during a growing season of 111 days compared with the original estimate of 127.3 kg calculated for an assumed growing season of 150 days, a difference of only 6%. The correspondence between the two estimates was coincidental. The original estimate was made at a time when the growing season had not been measured and the effect of ration and body size on growth efficiency was not precisely known. Corrections for these factors plus that for activity compensated for one another, closely approaching, by chance, the original value. 相似文献
The revised consumption of protein was 134.9kg (or 1407kg live weight of aquatic organisms, 444 kg/ha) during a growing season of 111 days compared with the original estimate of 127.3 kg calculated for an assumed growing season of 150 days, a difference of only 6%. The correspondence between the two estimates was coincidental. The original estimate was made at a time when the growing season had not been measured and the effect of ration and body size on growth efficiency was not precisely known. Corrections for these factors plus that for activity compensated for one another, closely approaching, by chance, the original value. 相似文献
54.
Bernadette Sánchez Kevin D. Pinkston Adina C. Cooper Carlos Luna Shelby T. Wyatt 《应用发育科学》2018,22(1):14-28
The aim of this study was to investigate the processes involved in developing close peer mentoring relationships among African American and Latino male adolescents in a school-based, group peer mentoring program. Qualitative one-on-one in-depth interviews were conducted with six school staff members, who administer the program, and 26 program participants about their experiences in the mentoring program. Data analysis revealed five program processes that led to close mentoring relationships: (a) rapport-building activities, (b) safe space, (c) mutual support, (d) group identity, and (e) trust. These processes ultimately led to bonding and friendship among program members, which further solidified the previous processes. Implications and future directions are discussed. 相似文献
55.
Cao X Antonyuk SV Seetharaman SV Whitson LJ Taylor AB Holloway SP Strange RW Doucette PA Valentine JS Tiwari A Hayward LJ Padua S Cohlberg JA Hasnain SS Hart PJ 《The Journal of biological chemistry》2008,283(23):16169-16177
Mutations in the gene encoding human copper-zinc superoxide dismutase (SOD1) cause a dominant form of the progressive neurodegenerative disease amyotrophic lateral sclerosis. Transgenic mice expressing the human G85R SOD1 variant develop paralytic symptoms concomitant with the appearance of SOD1-enriched proteinaceous inclusions in their neural tissues. The process(es) through which misfolding or aggregation of G85R SOD1 induces motor neuron toxicity is not understood. Here we present structures of the human G85R SOD1 variant determined by single crystal x-ray diffraction. Alterations in structure of the metal-binding loop elements relative to the wild type enzyme suggest a molecular basis for the metal ion deficiency of the G85R SOD1 protein observed in the central nervous system of transgenic mice and in purified recombinant G85R SOD1. These findings support the notion that metal-deficient and/or disulfide-reduced mutant SOD1 species contribute to toxicity in SOD1-linked amyotrophic lateral sclerosis. 相似文献
56.
Thomas A. Coudron Kent S. Shelby Mark R. Ellersieck Brittany R. Winston Holly J.R. Popham 《Entomologia Experimentalis et Applicata》2011,139(3):235-241
We report here the effects of a range of ascorbic acid concentrations (0.07, 0.3, 3.0, and 30.0 g l?1) in artificial diets on growth rates, adult weights, fecundity, and survival over two generations of the predatory stink bug, Podisus maculiventris (Say) (Heteroptera: Pentatomidae). Overall, a dietary level of 3.0 g l?1 gave the shortest developmental times over two generations. The likelihood of egg hatch at one ascorbic acid concentration compared to another concentration suggested that egg hatch increased as the concentration of ascorbic acid increased from 0.07 to 3.0 g l?1 and then declined from 3.0 to 30.0 g l?1. The combination of the maximum egg oviposition at 0.3 and 3.0 g l?1, egg hatch at 3.0 g l?1, and survival at 0.07 and 0.3 g l?1 suggests an overall superior performance at a concentration between 0.3 and 3.0 g l?1. Depletion of ascorbic acid below 3.0 g l?1 or addition of ascorbic acid above 3.0 g l?1 lowered the likelihood of egg hatch, which became more pronounced in the second generation. This is consistent with previously published information for phytophagous insects. 相似文献
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Melissa J. Morine Jacqueline Pontes Monteiro Carolyn Wise Candee Teitel Lisa Pence Anna Williams Baitang Ning Beverly McCabe-Sellers Catherine Champagne Jerome Turner Beatrice Shelby Margaret Bogle Richard D. Beger Corrado Priami Jim Kaput 《Genes & nutrition》2014,9(4)
The discovery of vitamins and clarification of their role in preventing frank essential nutrient deficiencies occurred in the early 1900s. Much vitamin research has understandably focused on public health and the effects of single nutrients to alleviate acute conditions. The physiological processes for maintaining health, however, are complex systems that depend upon interactions between multiple nutrients, environmental factors, and genetic makeup. To analyze the relationship between these factors and nutritional health, data were obtained from an observational, community-based participatory research program of children and teens (age 6–14) enrolled in a summer day camp in the Delta region of Arkansas. Assessments of erythrocyte S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH), plasma homocysteine (Hcy) and 6 organic micronutrients (retinol, 25-hydroxy vitamin D3, pyridoxal, thiamin, riboflavin, and vitamin E), and 1,129 plasma proteins were performed at 3 time points in each of 2 years. Genetic makeup was analyzed with 1 M SNP genotyping arrays, and nutrient status was assessed with 24-h dietary intake questionnaires. A pattern of metabolites (met_PC1) that included the ratio of erythrocyte SAM/SAH, Hcy, and 5 vitamins were identified by principal component analysis. Met_PC1 levels were significantly associated with (1) single-nucleotide polymorphisms, (2) levels of plasma proteins, and (3) multilocus genotypes coding for gastrointestinal and immune functions, as identified in a global network of metabolic/protein–protein interactions. Subsequent mining of data from curated pathway, network, and genome-wide association studies identified genetic and functional relationships that may be explained by gene–nutrient interactions. The systems nutrition strategy described here has thus associated a multivariate metabolite pattern in blood with genes involved in immune and gastrointestinal functions.
Electronic supplementary material
The online version of this article (doi:10.1007/s12263-014-0408-4) contains supplementary material, which is available to authorized users. 相似文献60.