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21.
Mohamad Ali Fulazzaky Teng Wee Seong Mohd Idrus Mohd Masirin 《Water, air, and soil pollution》2010,205(1-4):63-77
Water quality degradation in the Selangor River will still be present in the years to come since pollutant loads from poultry farms, municipal wastewaters, and industrial wastewaters are not envisaged to be handled effectively. This will be facing the problems of water quality status to use for multiple purposes and to provide its aquatic environment continuously. The water quality evaluation system is used to assess the water quality condition in the river. This system distinguishes two categories of water condition i.e., the water quality index and water quality aptitude. The assessment of water quality for the Selangor River from nine stations along the main stream, which concludes that water has been highly polluted (index 5) immediately downstream of station 02 Selangor River before confluence with Kubu River due to high concentration of microorganisms and immediately downstream of station 06 Selangor River before confluence with Batang Kali River due to high concentrations of microorganisms and suspended particles, was verified. Mineral micropollutants were found to gradually pollute the stream water, ranging from the unpolluted water (index 1) in the upstream to the bad quality (index 4) in the downstream area. 相似文献
22.
Cross-protective properties of infectious bursal disease viruses (IBDVs) were studied. Viruses represented different subtypes of serotype 1, including recently isolated viruses (variants), and a serotype 2 virus. Chickens were vaccinated at 3 weeks of age with inactivated vaccines containing 10(5), 10(6), 10(7), or 10(8) mean tissue-culture infectious dose of a given virus and challenged 2 weeks later using either 10(2) or 10(3.5) mean embryo infectious dose (EID50) of either a standard virus or a variant serotype 1 virus. Protection was evaluated at 5 and 10 days post-challenge, based on gross and microscopic lesions, body weight, and bursa/body-weight ratios. The serotype 2 virus did not confer protection on birds challenged with the serotype 1 viruses. Vaccines made of variant viruses at the low doses protected chickens challenged with the high or low doses of either the standard or the variant viruses. Vaccines made of the standard or variant strains at low doses protected against high or low challenge doses of the standard strain. Vaccines made of the high dose of any of the standard strains protected chickens against the variant virus when the low challenge dose (10(2) EID50) was used, but not when the high challenge dose (10(3.5) EID50) was used. The lowest dose of the standard viruses vaccines required to confer protection against the variant virus varied depending on the strain. Results indicated that protection depended on the strain and dose of both the vaccine and challenge viruses and that the variant strains and standard strains share a common protective antigen(s). 相似文献
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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
26.
Nisar M Kaleem WA Khan I Adhikari A Khan N Shah MR Khan IA Qayum M Samiullah Ismail M Aman A 《Fitoterapia》2011,82(7):1008-1011
Zizyphus oxyphylla Edgew is used in Pakistan as a folk medicinal remedy for inflammatory conditions, pains especially rheumatic pain, fevers, allergy and diabetes. The aim of the current study was to scientifically validate the folk use of Z. oxyphylla Edgew by using the isolated compound in vitro and in vivo levels. Kushecarpin A was isolated from ethyl acetate fraction of the plant crude extract. Molecular docking simulations predicted Kushecarpin A as a potential new lipoxygenase (LOX) inhibitor. Kushecarpin A showed significant lipoxygenase inhibition (IC50: 7.2 ± 0.02 μM) thus validated computational prediction. It also exhibited significant and highly significant inhibition (p < 0.05 and p < 0.01) of carrageenan-induced hind paw oedema at the doses of 5, 10 and 20 mg/kg. Kushecarpin A seems to be a potentially new anti-inflammatory compound responsible for anti-inflammatory activities of Z. oxyphylla Edgew. In vitro and in vivo anti-inflammatory inflammatory activities were found in good agreement with the folk medicinal use of Z. oxyphylla Edgew in inflammatory disorders. 相似文献
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The role of potassium in alleviating detrimental effects of abiotic stresses in plants 总被引:6,自引:0,他引:6
Ismail Cakmak 《植物养料与土壤学杂志》2005,168(4):521-530
Plants exposed to environmental stress factors, such as drought, chilling, high light intensity, heat, and nutrient limitations, suffer from oxidative damage catalyzed by reactive oxygen species (ROS), e.g., superoxide radical (O2equation/tex2gif-sup-1.gif–), hydrogen peroxide (H2O2) and hydroxyl radical (OHequation/tex2gif-sup-4.gif). Reactive O2 species are known to be primarily responsible for impairment of cellular function and growth depression under stress conditions. In plants, ROS are predominantly produced during the photosynthetic electron transport and activation of membrane‐bound NAD(P)H oxidases. Increasing evidence suggests that improvement of potassium (K)‐nutritional status of plants can greatly lower the ROS production by reducing activity of NAD(P)H oxidases and maintaining photosynthetic electron transport. Potassium deficiency causes severe reduction in photosynthetic CO2 fixation and impairment in partitioning and utilization of photosynthates. Such disturbances result in excess of photosynthetically produced electrons and thus stimulation of ROS production by intensified transfer of electrons to O2. Recently, it was shown that there is an impressive increase in capacity of bean root cells to oxidize NADPH when exposed to K deficiency. An increase in NADPH oxidation was up to 8‐fold higher in plants with low K supply than in K‐sufficient plants. Accordingly, K deficiency also caused an increase in NADPH‐dependent O2equation/tex2gif-sup-6.gif– generation in root cells. The results indicate that increases in ROS production during both photosynthetic electron transport and NADPH‐oxidizing enzyme reactions may be involved in membrane damage and chlorophyll degradation in K‐deficient plants. In good agreement with this suggestion, increases in severity of K deficiency were associated with enhanced activity of enzymes involved in detoxification of H2O2 (ascorbate peroxidase) and utilization of H2O2 in oxidative processes (guaiacol peroxidase). Moreover, K‐deficient plants are highly light‐sensitive and very rapidly become chlorotic and necrotic when exposed to high light intensity. In view of the fact that ROS production by photosynthetic electron transport and NADPH oxidases is especially high when plants are exposed to environmental stress conditions, it seems reasonable to suggest that the improvement of K‐nutritional status of plants might be of great importance for the survival of crop plants under environmental stress conditions, such as drought, chilling, and high light intensity. Several examples are presented here emphasizing the roles of K in alleviating adverse effects of different abiotic stress factors on crop production. 相似文献
29.
Scherer SW Cheung J MacDonald JR Osborne LR Nakabayashi K Herbrick JA Carson AR Parker-Katiraee L Skaug J Khaja R Zhang J Hudek AK Li M Haddad M Duggan GE Fernandez BA Kanematsu E Gentles S Christopoulos CC Choufani S Kwasnicka D Zheng XH Lai Z Nusskern D Zhang Q Gu Z Lu F Zeesman S Nowaczyk MJ Teshima I Chitayat D Shuman C Weksberg R Zackai EH Grebe TA Cox SR Kirkpatrick SJ Rahman N Friedman JM Heng HH Pelicci PG Lo-Coco F Belloni E Shaffer LG Pober B Morton CC Gusella JF Bruns GA Korf BR 《Science (New York, N.Y.)》2003,300(5620):767-772
30.
Al-Sheraji SH Ismail A Manap MY Mustafa S Yusof RM Hassan FA 《Journal of agricultural and food chemistry》2011,59(8):3980-3985
A dried high fiber product from bambangan (Mangifera pajang Kort.) fruit pulp was prepared and evaluated for proximate composition, functional properties, and soluble and insoluble dietary fiber composition. Mangifera pajang fibrous (MPF) consisted of 4.7% moisture, 0.8% fat, 4% protein, and 30 mg total polyphenol per g of dry sample, and 9, 79 and 88% soluble, insoluble and total dietary fiber, respectively. Water holding capacity, oil holding capacity, swelling, and solubility were found to be 9 g/g dry sample, 4 g/g dry sample, 16 mL/g dry sample, and 11%, respectively. The glucose dialysis retardation index of MPF was approximately double that of cellulose fiber. Soluble dietary fiber contained mannose, arabinose, glucose, rhamnose, erythrose, galactose, xylose, and fucose at 1.51, 0.72, 0.39, 0.16, 0.14, 0.05, 0.04, and 0.01%, respectively, with 5.8% uronic acid, while insoluble dietary fiber was composed of arabinose (18.47%), glucose (4.46%), mannose (3.15%), rhamnose (1.65%), galactose (1.20%), xylose (0.99%), and fucose (0.26%) with 15.5% uronic acid and 33.1% klason lignin. These characteristics indicate that MPF is a rich source of dietary fiber and has physicochemical properties which make it suitable as an added ingredient in various food products and/or dietetic, low-calorie high-fiber foods to enhance their nutraceutical properties. 相似文献