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81.
Enrobing of fish improves physical as well as consumer acceptance of low value fish. The present work was undertaken to utilize a low value fish with its bones by enrobing with cereal flour based coating. Three combinations of batters were prepared, and the fish was coated and fried; based on the sensory quality, 1:2 batter to water ratio was selected for product preparation. To determine the storage life, frozen par-fried samples were prepared and stored at ?18°C. Quality parameters such as pH, total volatile basic nitrogen, free fatty acids, peroxide value, thiobarbituric acid reactive substances, color, and sensory attributes were evaluated on a monthly basis. It was observed from chemical parameters and sensory scores of the product that the par-fried form can be stored for up to 5 months. This technology will provide a better opportunity for employment of coastal women.  相似文献   
82.
Coronary heart disease is the leading cause of death worldwide, affecting millions of men and women each year. Following an acute myocardial infarction, early and successful reperfusion therapy with thrombolytic therapy or primary percutaneous coronary intervention plays an important role in minimizing tissue injury associated with cessation of blood flow. The process of restoring blood flow to the ischemic myocardium, however, can induce additional injury. This phenomenon, termed myocardial ischemia-reperfusion (MI-R) injury, can paradoxically reduce the beneficial effects of myocardial reperfusion. MI-R injury is characterized by the formation of oxygen radicals upon reintroduction of molecular oxygen to the ischemic tissue, resulting in widespread lipid and protein oxidative modifications, mitochondrial injury, and cell death. In addition, studies have shown that MI-R is characterized by an inappropriate immune response in the microcirculation, resulting in leukocyte-endothelial cell interactions mediated by the upregulation of both leukocyte and endothelial cell adhesion molecules. Furthermore, MI-R ameliorates the production of certain cardioprotective factors such as nitric oxide. Advances in the generation of genetically modified mouse models enable researchers to identify the functional importance of genes involved in these processes.  相似文献   
83.
Nathan  S. Senthil  Chung  Paul Gene  Murugan  K. 《Phytoparasitica》2004,32(5):433-443
The effect of botanical insecticides and bacterial toxins on gut enzyme activity of larvae of the rice leaffolderCnaphalocrocis medinalis (Guenée) (Insecta: Lepidoptera: Pyralidae) was investigated. Gut enzyme activities were affected by botanical insecticides and bacterial toxin individually and in combination. When fed a diet of rice leaves treated with botanical insecticides and bacterial toxins, in bioassays the activities of gut tissue enzymes — acid phosphatases (ACP), alkaline phosphatases (ALP) and adenosine triphosphatases (ATPase) — of rice leaffolder larvae were affected. When combined, the effect was more severe at a low concentration. Larvae that were chronically exposed to botanical insecticides and bacterial toxins showed a reduction in weight (59–89%) and exhibited a significant reduction in ACP, ALP and ATPase activities. The combination ofBacillus thuringiensis kurstaki and botanical insecticides caused a decrease of twofold in enzyme activity even at reduced concentration. A synergistic effect was found when botanical insecticides and bacterial toxins were combined at low doses. These effects were most pronounced in early instars. Clear dose-response relationships were established with respect to enzyme activity. In conclusion: (i) biopesticides are relatively safe and biodegradable; (ii) a synergistic effect of botanical insecticides and bacterial toxins was found; (iii) less expensive, readily available and naturally occurring biopesticides could be an alternative for organic and inorganic pesticides in controlling RLF. http://www.phytoparasitica.org posting Sept. 28, 2004.  相似文献   
84.
85.
The epidemic of bud rot disease affecting oil palm in Colombia is primarily caused by Phytophthora palmivora. The pathogen has a cosmopolitan presence that includes Southeast Asia, but to date, bud rot has not been reported in this region. This study provides an overview of the potential risk of Malaysian P. palmivora isolates cross‐infecting other host species, including cocoa, durian, rubber and Malaysian oil palm planting materials (Dura × Pisifera, D × P). On cocoa pods, the durian isolate PP7 caused dark brown necrotic lesions. Detached leaf bioassays showed that P. palmivora isolates PP3 and PP7 infected different hosts, except rubber foliage without wounding. Inoculation tests on cocoa, durian and rubber seedlings caused brown necrotic lesions when stems were wounded, with 10% mortality in cocoa and durian at 17 days post‐inoculation (dpi). However, no further infection was observed, and lesions closed within 14–28 dpi on the non‐wounded seedlings. Pathogenicity tests of oil palm seedlings inoculated with isolates PP3 and PP7 indicated that Malaysian P. palmivora isolates were not pathogenic to oil palms based on localized infection observed only through wounding. Overall, the work demonstrated that Malaysian P. palmivora isolates were able to cross‐infect multiple hosts but did not show severe infections on oil palms.  相似文献   
86.
The aim of this investigation was to prepare and evaluate organic manures (vermicompost, compost and FYM) and mineral fertilizers on crop productivity and changes in soil organic carbon (SOC) and fertility under a four-year-old maize-wheat cropping system. The results demonstrated that yields and nutrient uptake by crops increased significantly in plots receiving manures and mineral fertilizers either alone or in combination than unfertilized control. Application of manures and fertilizers also enhanced SOC, mineral N, Olsen-P and ammonium acetate-extractable K (NH4OAc-K) after both the crops. Surface soil maintained greater build-up in SOC, mineral N, Olsen-P and NH4OAc-K than sub-surface soil. Plots amended with manures at 5 t ha?1 and 50% recommended dose of fertilizer (RDF) had pronounced impact on improving SOC and fertility after both the crops indicating that integrated use of manures and mineral fertilizers could be followed to improve and maintain soil fertility, increase crop productivity under intensive cropping system.  相似文献   
87.
The aim of this project was to study the translocation of potassium phosphonate within black pepper (Piper nigrum L.) and to elucidate the amount of chemical distributed through out the plant based on a tracer technique. Potassium phosphonate is a potential fungicide used against the pathogen Phytophthora capsici, which causes Phytophthora foot rot (Quick wilt) in the plant. Reports indicate that translocation of phosphonate is ambimobile, but there is no visual evidence for this. Potassium phosphonate labelled with radioactive phosphorus, 32P, was applied to the black pepper vine and bush pepper and its translocation to different parts of the pepper plant was studied using an autoradiography technique. The chemical which migrated to different parts of the plant was quantitatively estimated by measuring 32P on a liquid scintillation spectrometer following Cerenkov counting. Only traces of the chemical were lost to the soil through root systems. These results indicate that foliar sprays of potassium phosphonate to pepper could be a viable method of application for soil and foliar pathogens.  相似文献   
88.
Agroforestry as a strategy for carbon sequestration   总被引:2,自引:0,他引:2  
During the past three decades, agroforestry has become recognized the world over as an integrated approach to sustainable land use because of its production and environmental benefits. Its recent recognition as a greenhouse gas–mitigation strategy under the Kyoto Protocol has earned it added attention as a strategy for biological carbon (C) sequestration. The perceived potential is based on the premise that the greater efficiency of integrated systems in resource (nutrients, light, and water) capture and utilization than single‐species systems will result in greater net C sequestration. Available estimates of C‐sequestration potential of agroforestry systems are derived by combining information on the aboveground, time‐averaged C stocks and the soil C values; but they are generally not rigorous. Methodological difficulties in estimating C stock of biomass and the extent of soil C storage under varying conditions are compounded by the lack of reliable estimates of area under agroforestry. We estimate that the area currently under agroforestry worldwide is 1,023 million ha. Additionally, substantial extent of areas of unproductive crop, grass, and forest lands as well as degraded lands could be brought under agroforestry. The extent of C sequestered in any agroforestry system will depend on a number of site‐specific biological, climatic, soil, and management factors. Furthermore, the profitability of C‐sequestration projects will depend on the price of C in the international market, additional income from the sale of products such as timber, and the cost related to C monitoring. Our knowledge on these issues is unfortunately rudimentary. Until such difficulties are surmounted, the low‐cost environmental benefit of agroforestry will continue to be underappreciated and underexploited.  相似文献   
89.
Experiments were conducted during a 5 mo period (September 1975 to January 1976) to determine the Pb concentrations in Bangkok streets and blood Pb levels of Bangkok's population. A total of 185 air samples and 222 blood samples was collected and analyzed. Street Pb levels are in the range of 6.16 to 22.48 μg m?3 and blood Pb levels are in the range of 1 to 34 μg (100 g)?1 of whole blood, with an average value of 12.3 μg (100 g)P?1. The effects of various parameters on air and blood Pb levels are discussed in this paper. Air Pb levels are found to be closely related to traffic volume and proximity to the roads. Blood Pb levels are found to increase progressively with age, reaching a saturation value at about 40 yr of age. The average time spent daily on roads by the people and the distance of their residence/workplace from the main road are found to be major parameters, affecting the blood Pb levels. There is no evidence to show that blood and air Pb levels are directly related, at the present ambient exposure levels.  相似文献   
90.
The interaction of antiperoxidative flavonoids artocarpin (AR), cycloartocarpin (CAR), dalspinin (DP), dalspinosin (DPO), and dalspinin-7-O-galactoside (DPG) with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS(.+)) and O2(-.) was studied in phosphate buffer (pH 7.4). The ability of these compounds to inhibit lipid peroxidation and DNA scission was also investigated. The radical scavenging efficiency of flavonoids is demonstrated by the reduction of nitrogen-centered radical cation (ABTS(.+)). The reduction of ABTS(.+) follows the order quercetin > morin > Trolox > AR > DPO > CAR > DP. Inhibition of lipid peroxidation was studied by following Mb(IV) reduction, induced by lipid, arachidonic acid. These results are compared with those obtained for well-known antioxidants such as quercetin, morin, and Trolox. The structure-activity relationships between chemical structures of the flavonoids and their radical scavenging activities are anlayzed. The scavenging of O2(-.), inhibition of lipid peroxidation, and DNA damage depend on the oxidation potential of the flavonoids. The possible mechanism for radical scavenging activities of flavonoids in relation to their structure is also outlined.  相似文献   
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