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11.
Abdelfattah Z. M. Salem Ahmed E. Kholif Mona M. Y. Elghandour Saul R. Hernandez Ignacio A. Domínguez‐Vara Miguel Mellado 《Animal Science Journal》2014,85(9):853-860
This study was conducted to investigate the effects of increasing levels of extracts of Byrsonima crassifolia, Celtis pallida, Enterolobium cyclocarpum, Fraxinus excelsior, Ficus trigonata, Phoradendrom brevifolium and Prunus domestica on in vitro gas production (GP) and ruminal fermentation of a high concentrate diet. Plant extracts were prepared at 1 g dry matter (DM)/8 mL of solvent mixture (methanol : ethanol : water, 1:1:8) and added at levels of 0, 0.6, 1.2 and 1.8 mL/g DM of a high concentrate diet. In vitro GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48 and 72 h of incubation. Increasing addition of extracts linearly increased (P < 0.001), the GP24, GP48 and GP72 (mL/g DM), and linearly decreased (P < 0.001), the discrete GP lag time. Moreover, increasing extract doses linearly increased (P < 0.001) the asymptotic GP and decreased (P < 0.001) the rate of GP. GP6 was not impacted by treatments and GP12 increased linearly (P = 0.01) with increasing addition of extracts. Rumen pH declined linearly (P < 0.05) with increasing doses of extracts added. As no interactions (P > 0.05) occurred between the extracts and doses, it could be conclude that all extracts positively modified rumen fermentation at doses of 1.2 to 1.8 mL extract/g diet DM. 相似文献
12.
Tom Lichatowich Salem Al-Thobaity Max Arada Feisal Bukhari 《Aquaculture (Amsterdam, Netherlands)》1984,40(3):269-271
Data on the G.S.I. of adults and appearance of fry indicated a regular lunar spawning cycle of S. rivulatus within a seasonal breeding period. A mass collection technique yielding 5000–7000 fry per day was developed. 相似文献
13.
Salem Fathallah Mohamed Néjib Medhioub Amel Medhioub Hamadi Boussetta 《Aquaculture Research》2010,42(1):139-146
In this work, we investigated the nutritional status of Ruditapes decussatus juveniles under different rearing conditions, using biochemical indices (RNA/DNA ratio and protein content) and the linear instantaneous growth rate (IGR). Two experiments were conducted to study the effect of starvation, addition of substrate (sand) as rearing support and diet composition on somatic growth and biochemical indices. Results show that biochemical indices of fed juveniles were significantly (P<0.05) higher. Highest RNA/DNA values and protein content were recorded in fed juveniles reared with substrate (P<0.05); conversely, lowest values were recorded in starved ones reared without substrate. In the second experiment, the highest RNA/DNA ratio was recorded in juveniles fed with control algal mixture composed of species commonly used in bivalve nurseries [Isochrysis galbana (clone T-Iso), Chaetoceros calcitrans and Tetraselmis suecica] and lowest in those fed with algal species isolated from Tunisian coasts. This confirms the usefulness of the RNA/DNA ratio and protein content in the clam's nutritional status evaluation. This assay is useful to provide information about the nutritional status and health of the clam in field conditions. 相似文献
14.
Karioti A Skaltsa H Demetzos C Perdetzoglou D Economakis CD Salem AB 《Journal of agricultural and food chemistry》2003,51(22):6505-6508
Essential oils from hydroponically cultivated Salvia fruticosa were analyzed by GC-MS techniques. Three different levels of nitrogen (100, 150, and 200 mg/L) were used in the nutrient solution for the cultivation, using the nutrient film technique. A total of 79 compounds were identified, and qualitative and quantitative differences have been observed between the samples collected at full bloom (flowering stage) and at the end of the seed formation stage. 1,8-Cineole, beta-caryophyllene, and viridiflorol were the predominant constituents in most cases. 13-epi-Manool was identified by using GC parameters and mass spectrum fragmentation pattern, whereas labd-7,13-dien-15-ol, a labdane type diterpene, was identified for the first time in the genus Salvia, using GC parameters and an authentic sample. The results obtained from GC-MS analyses were submitted to chemometric analysis. 相似文献
15.
Fatma Basyoni Salem 《Water, air, and soil pollution》1991,60(1-2):27-33
The proposed method is used for determination of trace amounts of phosphate in water samples especially of Dakahlia Governorate. The recommended procedure is based on the formation of molydophosphoric acid which upon, selective reduction with the reducing agent oxalyldihydrazide produces a blue color due to the molybdenum blue. The intensity of the blue color is proportional to the amount of phosphate initially incorporated in the heteropoly acid. The resulting blue complex could be determined in the range of 2.25 to 22.46 μg P with molar absorptivity of 33418 L?1 mol?1 cm?1 at 880 nm. The reduction of phosphomolybdate complex by oxalyldihydrazide is chosen in the work and the result is compared with those obtained with the reducing agent potassium antimonyl tartrate, the reduction methods are frequently recommended for manual analysis of waters and wastes for P. 相似文献
16.
Anti-uveal melanoma activity-guided fractionation of the MeOH extract of Acacia nilotica pods resulted in the isolation of the new compound gallocatechin 5-O-gallate (5) in addition to methyl gallate (1), gallic acid (2), catechin (3), catechin 5-O-gallate (4), 1-O-galloyl-β-D-glucose (6), 1,6-di-O-galloyl-β-D-glucose (7) and digallic acid (8). The structures of the isolated compounds were elucidated on the basis of HRESIMS, NMR spectroscopy and CD data. In addition to uveal melanoma, the antiproliferative activities of the isolated compounds and the related compound epigallocatechin 3-O-gallate (EGCG) were evaluated against cutaneous melanoma, ovarian cancer, glioblastoma and normal retinal pigmented cells. 相似文献
17.
Faham S Watanabe A Besserer GM Cascio D Specht A Hirayama BA Wright EM Abramson J 《Science (New York, N.Y.)》2008,321(5890):810-814
Membrane transporters that use energy stored in sodium gradients to drive nutrients into cells constitute a major class of proteins. We report the crystal structure of a member of the solute sodium symporters (SSS), the Vibrio parahaemolyticus sodium/galactose symporter (vSGLT). The approximately 3.0 angstrom structure contains 14 transmembrane (TM) helices in an inward-facing conformation with a core structure of inverted repeats of 5 TM helices (TM2 to TM6 and TM7 to TM11). Galactose is bound in the center of the core, occluded from the outside solutions by hydrophobic residues. Surprisingly, the architecture of the core is similar to that of the leucine transporter (LeuT) from a different gene family. Modeling the outward-facing conformation based on the LeuT structure, in conjunction with biophysical data, provides insight into structural rearrangements for active transport. 相似文献
18.
Genetic polymorphism of plastid DNA in Tunisian date-palm germplasm (Phoenix dactylifera L.) detected with PCR-RFLP 总被引:1,自引:0,他引:1
Sakka Hela Zehdi Salwa Ould Mohamed Salem Ali Rhouma Abdelmajid Marrakchi Mohamed Trifi Mokhtar 《Genetic Resources and Crop Evolution》2004,51(5):479-487
Fifteen plastid fragments were amplified from a set of Tunisian date-palm accessions by PCR with consensus primers and analysed by RFLP. Polymorphic DNA bands were obtained as reliable molecular markers to estimate genetic distances among the accessions and to examine their phylogenetic relationships. The ctDNA PCR-RFLP method permitted the identification of two haplotypes that differ in the presence or absence of the HinfI restriction site. Phenetic groups composed of cultivars clustered together but does not constitute monophyletic groups. This typology agrees with the haplotypes' organization and provides a common genetic background within the implied varieties. 相似文献
19.
Lactic acidosis: a factor associated with equine laminitis 总被引:4,自引:0,他引:4
H E Garner D P Hutcheson J R Coffman A W Hahn C Salem 《Journal of animal science》1977,45(5):1037-1041
20.
An in vivo technique was developed to observe colonisation of mushroom compost by Trichoderma spp. Isolates of T. harzianum (Th2), T. harzianum (Th1), T. koningii (Tk) and T. viride (Tv) were artificially introduced into compost using a mini-bag system. Wheat grains, colonised by Trichoderma spp, were placed centrally on a layer of compost at the bottom of 1-litre polythene bags which were then filled with 350 g of spawned or un-spawned compost, and partially sealed. After 14 and 21 days incubation at 27 degrees C, the bags were assessed for recovery of Trichoderma from middle and top zones using a needle stab re-isolation technique and a visual colonisation scoring system. Visible green mould contamination, similar to that observed in practice, developed within 21 days. The visual colonisation scoring was reliably related to the re-isolation success. In this evaluation, Trichoderma spp showed considerable differences in their relative abilities to colonise spawned and un-spawned compost, with Th2 isolates being consistently superior to the other isolates of Th1, Tk and Tv in colonising spawned compost. This technique was employed to evaluate the effects of fungicides on the colonisation of mushroom compost by three Trichoderma spp: Th2, Th1 and Tk, using 1-litre and 5-litre mini-bag systems. Aqueous suspensions of benomyl, carbendazim, thiabendazole, prochloraz and prochloraz+carbendazim incorporated into the compost at 50 mg litre(-1), or applied to spawn at 50 mg kg(-1), reduced the colonisation by Trichoderma spp. Prochloraz and prochloraz+carbendazim were superior to benomyl, carbendazim or thiabendazole in reducing compost colonisation by Th2, Th1 and Tk, with Th2 being the most persistent type, capable of colonising treated compost in the presence of all five fungicides. The prochloraz+carbendazim mixture, not normally used in mushroom production, was equal to or better than prochloraz alone. The incidence of green mould colonisation by Th2 was as extensive in the 5-litre compost bags as in the 1-litre bags, but colonisation by Th1 and Tk was more apparent in the 5-litre bags. The in vivo mini-bag evaluations using wheat grain Trichoderma inoculum and needle stab re-isolation procedures proved an efficient method for studying colonisation and screening for effectiveness of fungicides applied to mushroom compost or spawn. 相似文献