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排序方式: 共有1334条查询结果,搜索用时 15 毫秒
101.
Abdelwahab SI Hassan LE Sirat HM Yagi SM Koko WS Mohan S Taha MM Ahmad S Chuen CS Narrima P Rais MM Hadi AH 《Fitoterapia》2011,82(8):1190-1197
The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS. 相似文献
102.
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
103.
Maruyama N Mohamed Salleh MR Takahashi K Yagasaki K Goto H Hontani N Nakagawa S Utsumi S 《Journal of agricultural and food chemistry》2002,50(15):4323-4326
We purified four single molecular species of beta-conglycinin heterotrimers consisting of the alpha and beta subunits or the alpha' and beta subunits from mutant soybean cultivars lacking the alpha or alpha' subunit, respectively, and examined their structural features and physicochemical functions. The extent of the hydrophobicities of the heterotrimers was related to the number of the alpha or alpha' subunit. The thermal stabilities of the heterotrimers were mainly conferred by the subunit which had lower thermal stability. Solubilities at low ionic strength (mu = 0.08) of the heterotrimers containing the alpha or alpha' subunit were very similar to those of the alpha and alpha' homotrimers, respectively. Emulsifying abilities and heat-induced associations of the heterotrimers containing one beta subunit were similar to those of the alpha or alpha' homotrimer, whereas those of the heterotrimers containing two beta subunits were similar to those of the beta homotrimer. 相似文献
104.
The effects of wheat straw and different forms of N on denitrification and N immobilization were studied in an anaerobic water-sediment system. The water-sediment system was supplemented with various combinations of wheat straw and 15N-labelled and unlabelled (NH4)2SO4 or KNO3, and incubated anaerobically at 30°C for 10 days. 15N-labelled and unlabelled NO
inf3
sup-
, NO
inf2
sup-
, NH
inf4
sup+
, and organic N were determined in the water-sediment system. The gases evolved (N2, CO2, N2O, and CH4) were analyzed by gas chromatography at regular intervals. Larger quantities of 15N2–N and organic 15N were formed in wheat straw-amended systems than in non-amended systems. Trends in CO2 production were similar to those of N2–N evolution. The evolution of N2O and CH4 was negligible. Denitrification processes accounted for about 22 and 71% of the added 15NO
inf3
sup-
–N in the absence and presence of wheat straw, respectively. The corresponding denitrification rates were 3.4 and 12.4 g 15Ng-1 dry sediment day-1. In systems amended with 15NO
inf3
sup-
–N and 15NO
inf3
sup-
+NH
inf4
sup+
–N without wheat straw, 1.82 and 1.58%, respectively, of the added 15NH
inf3
sup-
–N was immobilized. The corresponding figures for the same systems supplemented with wheat straw were 5.08 and 4.10%, respectively. Immobilization of 15NO
inf4
sup+
–N was higher than that of 15NO
inf3
sup-
–N. The presence of NO
inf3
sup-
–N did not stimulate NH
inf4
sup+
–N immobilization. 相似文献
105.
Mohamed R. Lasheen Salwa A. Shehata Gamila H. Ali 《Water, air, and soil pollution》1990,50(1-2):19-30
The Algal Assay Procedure Bottle Test was used to investigate the effect of Cd, Cu, and Cr (VI) on the growth of Nile water algae. The results of this investigation indicated that Cd has slight inhibitory effects on algal growth at low concentration (0.05 mg L?1), while it was inhibiting algal growth at higher concentration (> 1.0 mg L?1). In contrast, Cu and Cr did not affect algal growth in all investigated concentrations. Combinations of Cd with Cu and Cr seemed to interact synergistically. The synergism between Cd and Cu was more pronounced than between Cd and Cr. Clear changes in the diversity and redundancy of algal structure took place after metal addition. The inhibitory effect of the studied metals was in the following order: Cd-Cu > Cd - Cr > Cd > Cu > Cr. 相似文献
106.
In an attempt to evaluate whether breeding and selection for high yielding capacity changed the P requirement of modem wheat cultivars. the response of two wheat cultivars to different levels of P supply was investigated. A traditional cultivar (‘Peragis’) and a modern spring-wheat cultivar (‘Cosir’) were cultivated in a C-loess low in available P and high in CaCO3 in 120 cm high PVC tubes. In addition and for comparison, nutrient solution experiments were also conducted. Shoot growth, root growth. P uptake. P translocation and P distribution within the shoot at different developmental stages were compared. The grain yield of the modern cultivar ‘Cosir’ was higher at limiting and non-limiting P supply and. therefore, this cultivar can be considered as more P-efficient than the traditional cultivar. Grain yield reduction at low P supply was mainly due to an inhibition of tillering and thus lower number of ears per plant, whereas the number of grains per ear was hardly affected. Reduced tillering at low P supply could not be related to P concentrations in the shoot meristematic tissues which were generally much higher than in other plant tissues and kept at an elevated level even at limiting P supply. Root branching (1st order laterals) was reduced at limiting P supply in ‘Cosir’ but not in ‘Peragis’ which, generally, had lower numbers of laterals at the beginning of tillering. From the results it can be concluded that the main factors contributing to the higher P efficiency of the modern cultivar ‘Cosir’ are (i) efficient use of assimilates for root-growth characteristics which enhance P acquisition: enhanced root branching and thus smaller mean root diameter and longer root hairs, (ii) an efficient P uptake system, (iii) efficient remobilization of P from vegetative plant organs to the grains, and most importantly (iv) lower P requirement for grain yield formation because of lower ear number per plant but higher grain number per ear. 相似文献
107.
Abdelmonem Mohamed Amer 《Agricultural Water Management》2011,98(5):815-822
Surface irrigation analysis and design require the knowledge of the variation of the cumulative infiltration water Z (L) (per unit area) into the soil as a function of the infiltration time t (T). The purpose of this study is to evaluate water infiltration and storage under surface irrigation in an alluvial clay soil cultivated with grape yield, and to determine if partially wetted furrow irrigation has more efficient water storage and infiltration than traditional border irrigation. The two irrigation components considered were wet (WT) and dry (DT) treatments, at which water applied when available soil water reached 65% and 50%, and the traditional border irrigation control. Empirical power form equations were obtained for measured advance and recession times along the furrow length during the irrigation stages of advance, storage, depletion and recession. The infiltration (cumulative depth, Z and rate, I) was functioned to opportunity time (to) in minute for WT and DT treatments as: ZWT = 0.528 to0.6, ZDT = 1.2 to0.501, IWT = 19 to−0.4, and IDT = 36 to−0.498. The irrigation efficiency and soil water distribution have been evaluated using linear distribution and relative schedule depth. Coefficient of variation (CV) was 5.2 and 9.5% for WT and DT under furrow irrigation system comparing with 7.8% in border, respectively. Water was deeply percolated as 11.88 and 19.2% for wet and dry furrow treatments, respectively, compared with 12.8% for control, with no deficit in the irrigated area. Partially wetted furrow irrigation had greater water-efficiency and grape yield than both dry furrow and traditional border irrigations, where application efficiency achieved as 88.1% for wet furrow irrigation that achieved high grape fruit yield (30.71 Mg/ha) and water use efficiency 11.9 kg/m3. 相似文献
108.
109.
Sanloup C Schmidt BC Chamorro Perez EM Jambon A Gregoryanz E Mezouar M 《Science (New York, N.Y.)》2005,310(5751):1174-1177
The reactivity of xenon with terrestrial oxides was investigated by in situ synchrotron x-ray diffraction. At high temperature (T > 500 kelvin), some silicon was reduced, and the pressure stability of quartz was expanded, attesting to the substitution of some xenon for silicon. When the quartz was quenched, xenon diffused out and only a few weight percent remained trapped in samples. These results show that xenon can be covalently bonded to oxygen in quartz in the lower continental crust, providing an answer to the missing xenon problem; synthesis paths of rare gas compounds are also opened. 相似文献
110.