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51.
An experiment was conducted with Starcross layers to evaluate the replacement value of sunflower meal (SFM) for cotton seed meal (CSM) and sesame meal (SM). The birds (aged 24 weeks) were given 4 isonitrogenous and isocaloric rations containing 0, 5, 10 and 15% dehulled sunflower meal. The substitution of SFM for CSM and SM did not generally affect the egg production, feed consumption, feed conversion nor did it have any effect on the quality of eggs as measured by Haugh Units (HU) and yolk index. Egg shell thickness, however, improved by increasing dietary levels of SFM. The feed costs per hen were generally lower for the SFM group since SFM was cheaper than CSM and SM. 相似文献
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53.
Weyand S Shimamura T Yajima S Suzuki S Mirza O Krusong K Carpenter EP Rutherford NG Hadden JM O'Reilly J Ma P Saidijam M Patching SG Hope RJ Norbertczak HT Roach PC Iwata S Henderson PJ Cameron AD 《Science (New York, N.Y.)》2008,322(5902):709-713
The nucleobase-cation-symport-1 (NCS1) transporters are essential components of salvage pathways for nucleobases and related metabolites. Here, we report the 2.85-angstrom resolution structure of the NCS1 benzyl-hydantoin transporter, Mhp1, from Microbacterium liquefaciens. Mhp1 contains 12 transmembrane helices, 10 of which are arranged in two inverted repeats of five helices. The structures of the outward-facing open and substrate-bound occluded conformations were solved, showing how the outward-facing cavity closes upon binding of substrate. Comparisons with the leucine transporter LeuT(Aa) and the galactose transporter vSGLT reveal that the outward- and inward-facing cavities are symmetrically arranged on opposite sides of the membrane. The reciprocal opening and closing of these cavities is synchronized by the inverted repeat helices 3 and 8, providing the structural basis of the alternating access model for membrane transport. 相似文献
54.
In Pakistan, particularly in Punjab Province, it is difficult for agrofarmers to combine their indigenous knowledge and modern scientific methods to evaluate existing traditional farming systems and forestry practices. This requires an evaluation of indigenous soil classification in simple terms along with knowledge of the local flora, especially trees. This study focuses on land suitability classification for trees in the Attock District of Punjab, Pakistan. A survey was conducted which included interviews of local agrofarmers as well as standard soil analyses including both chemical and physical determinations of local soil types. An evalu- ation of soil types for cultivation of various crops was carried out given its total extent, component soil series and their proportions, spotting characteristics of each soil series and their major limitations/hazards for trees/crops. These would lead to the identification of various tree species according to soil characteristics. Then, according to the soil types and species, a land suitability map was obtained for the choice of tree species by using geographic information system (GIS) software. Land suitability classification will help local agroforesters/agrofarmers in matching suitable agricultural trees/crops properly for different soils in the area. 相似文献
55.
Mirza Hasanuzzaman K. Nahar M. M. Rohman T. I. Anee Y. Huang M. Fujita 《Gesunde Pflanzen》2018,70(4):185-194
Although silicon (Si) has showed its potential role in mitigating abiotic stress-induced damages in many plant species its role in coordinated induction of antioxidant defense is yet to be elucidated. Therefore, we studied rapeseed (Brassica napus) seedlings applied with exogenous Si for changes occurring in antioxidant defense and glyoxalase systems. Seedlings (12-day-old) grown semi-hydroponically were exposed to Si (silicon dioxide, SiO2; 1?mM) solely and in combination with NaCl (100 and 200?mM) for 48?h. Salinity created oxidative damage by increasing H2O2 and malondialdehyde (MDA) contents resulting in disruption of antioxidant defense system and in arousing methylglyoxal (MG) toxicity by the down-regulation of glyoxalase enzyme activities. Exogenous Si treatment showed reduction of both H2O2 and MDA contents and up-regulation of antioxidant components including the activities of related enzymes (APX, MDHAR, DHAR, GR, GST, GPX and CAT) and the contents of AsA and GSH. Enhanced activities of glyoxalase I (Gly I) and glyoxalase II (Gly II) detoxified the toxic MG. Thus, this study clearly indicates that Si improved plant tolerance to salinity stress through enhancement of both antioxidant defense and glyoxalase systems that led to reduced oxidative damage and MG toxicity. 相似文献