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81.
Kimberly A. Copeland Wade O. Watanabe Patrick M. Carroll 《Journal of the World Aquaculture Society》2002,33(2):97-109
The effects of four practical diets on growth, feed utilization, and body composition of wild‐caught juvenile and subadult black sea bass Centropristis striata (316 ± 113 g =±± SD) were compared for 221 d in a recirculating tank system consisting of 12 2,660‐L tanks. Salinity averaged 33.5 ppt and temperature averaged 20.9 C but vaned from 12 to 27.1 C. Diets differed in crude protein (CP) and crude lipid (CL) as follows: 1) low CP (44.0%), low CL (11.4%) trout diet; 2) low CP (44.8%), high CL (15.0%) trout diet; 3) midlevel CP (47.9%), midlevel CL (12.8%) Bounder diet; and 4) high CP (53.9%), high CL (15.1%) marine finfish diet. Energy: protein ratios (E: P) were 44.6, 45.3, 41.8, and 39.1 W/g. Survival to 221 d on all diets was 100%. Significant (P < 0.05) differences in growth rates were observed among diets. Final weights were higher for midlevel and high CP diets 3 and 4 (1,051 and 1,013 g) than for low CP diet 1 (873 g). Relative growth rate (RGR, % total increase in weight), specific growth rate (SGR, % increase in body weight/d), and daily weight gain (DWG, g/d) were higher for higher CP diets 3 and 4 (RGR = 223 and 221; SGR = 0.53; DWG = 3.28 and 3.16), than for low CP diet 1 (RGR = 181; SGR = 0.47; DWG = 2.54). There were no significant differences between initial and final whole body protein and fiber content among diets. Lipid and gross energy levels significantly increased (P < 0.0001) in all treatments while moisture levels significantly decreased (P < 0.001). Although these differences were not significant, feed conversion ratio (FCR = dry weight fed/wet weight gain) was lower for fish given midlevel CP diet 3 (1.49) and high CP diet 4 (1.52) than for those fed low CP diets 1 and 2 (1.60 and 1.62). Protein efficiency ratios (PER = weight gain/weight protein fed) (1.43 to 1.24), apparent net protein retention (ANPR = weight protein gain/weight protein fed) (20 to 25%), and apparent net energy retention (ANER = energy gain/energy fed) (53.3 to 56.8%) were not significantly different among treatments. The midlevel CP (50%), midlevel CL (12%) diet maximized growth rates and was also significantly less expensive per kg fish weight produced ($1.40) than the high CP diet ($1.94) which produced the second highest growth rates. These results demonstrated that wild‐caught black sea bass can be successfully reared in recirculating tanks from juvenile to marketable sizes with high survival and with good feed conversion and growth on commercially prepared diets with a wide range of protein and lipid levels. 相似文献
82.
Calliste CA Trouillas P Allais DP Duroux JL 《Journal of agricultural and food chemistry》2005,53(2):282-288
The antioxidant potential of Castanea sativa Mill. leaf (sweet chestnut) was explored as a new source of active extracts. The capacity of the different fractions issued from aqueous, methanol, and ethyl acetate extracts to inhibit the stable free radical 2,2-diphenyl-1-pycryl-hydrazyl, superoxide anion, and hydroxyl radical was measured by electronic spin resonance. Their scavenging potential was analyzed versus their amount of phenolic compounds. Among the active fractions, the most effective one was A6, an ethyl acetate fraction, which contained a high level of total phenolic compounds (29.1 g/100 g). Thus, a different extraction procedure was performed to concentrate the active compounds of A6 in the new C. sativa leaf extract (CSLE). Compared to reference antioxidants (quercetin and vitamin E) and standard extracts (Pycnogenol, from French Pinus maritima bark, and grape marc extract), it was observed that A6 and CSLE have high antioxidant potentials, equivalent to at least those of reference compounds. 相似文献
83.
Mbithi-Mwikya S Van Camp J Mamiro PR Ooghe W Kolsteren P Huyghebaert A 《Journal of agricultural and food chemistry》2002,50(10):3030-3036
Finger millet (Eleusine coracana), kidney beans (Phaseolus vulgaris), peanuts (Arachis hypogoea), and mango (Mangifera indica) were processed separately and then combined, on the basis of their amino acid scores and energy content, into a complementary food for children of weaning age. The finger millet and kidney beans were processed by germination, autoclaving, and lactic acid fermentation. A mixture containing, on a dry matter basis, 65.2, 19.1, 8.0, and 7.7% of the processed finger millet, kidney beans, peanuts, and mango, respectively, gave a composite protein with an in vitro protein digestibility of 90.2% and an amino acid chemical score of 0.84. This mixture had an energy density of 16.3 kJ.g(-1) of dry matter and a decreased antinutrient content and showed a measurable improvement in the in vitro extractability for calcium, iron, and zinc. A 33% (w/v) pap made from a mix of the processed ingredients had an energy density of 5.4 kJ.g(-1) of pap, which is sufficient to meet the energy requirements of well-nourished children of 6-24 months of age at three servings a day and at the FAO average breast-feeding frequency. 相似文献
84.
Jér?me?MathieuEmail author Jean-Pierre?Rossi Michel?Grimaldi Philippe?Mora Patrick?Lavelle Corinne?Rouland 《Biology and Fertility of Soils》2004,40(5):300-305
The influence of three spatially hierarchical factors upon soil macrofauna biodiversity was studied in four pasture plots in eastern Amazonia. The first factor was the local depth of the soil. The second factor was the ground cover type on the soil samples (bare ground, grass tufts, dead trees lying on the ground). The third factor was the dimensions of the grass tufts sampled (size and shape). The effect of each factor upon the morphospecies richness and density of total soil macrofauna was analysed. Detailed results are given for earthworms, termites, ants, beetles and spiders. All factors significantly affected the morphospecies richness and/or density of the soil macrofauna. The type of ground cover had the strongest influence, affecting the total richness and density of the soil macrofauna and of almost all the groups represented. The soil depth affected only the density of the termites and the global morphospecies richness. Interactions between soil depth and ground cover type affected the total macrofauna morphospecies richness and the density of the earthworms. The dimensions of the grass tuft influenced the global morphospecies richness, the morphospecies richness of the ants and the density of the spiders. 相似文献
85.
CENH3 is a centromere-specific histone H3 variant essential for kinetochore assembly. Despite its central role in centromere function, there has been no conclusive evidence supporting CENH3 as sufficient to determine centromere identity. To address this question, we artificially targeted Drosophila CENH3 (CENP-A/CID) as a CID-GFP-LacI fusion protein to stably integrated lac operator (lacO) arrays. This ectopic CID focus assembles a functional kinetochore and directs incorporation of CID molecules without the LacI-anchor, providing evidence for the self-propagation of the epigenetic mark. CID-GFP-LacI-bound extrachromosomal lacO plasmids can assemble kinetochore proteins and bind microtubules, resulting in their stable transmission for several cell generations even after eliminating CID-GFP-LacI. We conclude that CID is both necessary and sufficient to serve as an epigenetic centromere mark and nucleate heritable centromere function. 相似文献
86.
Colin PL 《Science (New York, N.Y.)》2003,300(5626):1657-9; author reply 1657-9
87.
Linder P 《Science (New York, N.Y.)》2004,304(5671):694-695
88.
Thorleifsson G Magnusson KP Sulem P Walters GB Gudbjartsson DF Stefansson H Jonsson T Jonasdottir A Jonasdottir A Stefansdottir G Masson G Hardarson GA Petursson H Arnarsson A Motallebipour M Wallerman O Wadelius C Gulcher JR Thorsteinsdottir U Kong A Jonasson F Stefansson K 《Science (New York, N.Y.)》2007,317(5843):1397-1400
Glaucoma is a leading cause of irreversible blindness. A genome-wide search yielded multiple single-nucleotide polymorphisms (SNPs) in the 15q24.1 region associated with glaucoma. Further investigation revealed that the association is confined to exfoliation glaucoma (XFG). Two nonsynonymous SNPs in exon 1 of the gene LOXL1 explain the association, and the data suggest that they confer risk of XFG mainly through exfoliation syndrome (XFS). About 25% of the general population is homozygous for the highest-risk haplotype, and their risk of suffering from XFG is more than 100 times that of individuals carrying only low-risk haplotypes. The population-attributable risk is more than 99%. The product of LOXL1 catalyzes the formation of elastin fibers found to be a major component of the lesions in XFG. 相似文献
89.
Intention is central to the concept of voluntary action. Using functional magnetic resonance imaging, we compared conditions in which participants made self-paced actions and attended either to their intention to move or to the actual movement. When they attended to their intention rather than their movement, there was an enhancement of activity in the pre-supplementary motor area (pre-SMA). We also found activations in the right dorsal prefrontal cortex and left intraparietal cortex. Prefrontal activity, but not parietal activity, was more strongly coupled with activity in the pre-SMA. We conclude that activity in the pre-SMA reflects the representation of intention. 相似文献
90.
Li L Thomas RM Suzuki H De Brabander JK Wang X Harran PG 《Science (New York, N.Y.)》2004,305(5689):1471-1474
We describe the synthesis and properties of a small molecule mimic of Smac, a pro-apoptotic protein that functions by relieving inhibitor-of-apoptosis protein (IAP)-mediated suppression of caspase activity. The compound binds to X chromosome- encoded IAP (XIAP), cellular IAP 1 (cIAP-1), and cellular IAP 2 (cIAP-2) and synergizes with both tumor necrosis factor alpha (TNFalpha) and TNF-related apoptosis-inducing ligand (TRAIL) to potently induce caspase activation and apoptosis in human cancer cells. The molecule has allowed a temporal, unbiased evaluation of the roles that IAP proteins play during signaling from TRAIL and TNF receptors. The compound is also a lead structure for the development of IAP antagonists potentially useful as therapy for cancer and inflammatory diseases. 相似文献