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361.
Improved nitrogen status enhances zinc and iron concentrations both in the whole grain and the endosperm fraction of wheat 总被引:6,自引:0,他引:6
This study was conducted to assess the role of increasing N supply in enrichment of whole grain and grain fractions, particularly the endosperm, with Zn and Fe in wheat. The endosperm is the most widely consumed part of wheat grain in many countries. Plants were grown in the greenhouse with different soil applications of N and Zn and with or without foliar Zn spray. Whole grain and grain fractions were analyzed for N, P, Zn and Fe. Increased N supply significantly enhanced the Zn and Fe concentrations in all grain fractions. In the case of high Zn supply, increasing N application enhanced the whole grain Zn concentration by up to 50% and the endosperm Zn by over 80%. Depending on foliar Zn supply, high N elevated the endosperm Fe concentration up to 100%. High N also generally decreased the P/Zn and P/Fe molar ratios in whole grain and endosperm. The results demonstrate that improved N nutrition, especially when combined with foliar Zn treatment, is effective in increasing Zn and Fe of the whole grain and particularly the endosperm fraction, at least in the greenhouse, and might be a promising strategy for tackling micronutrient deficiencies in countries where white flour is extensively consumed. 相似文献
362.
Rice straw fibers have been used as reinforcing fillers in different polymers, tow composites were prepared by using polyvinyl
alcohol and polystyrene polymers with different ratio of polymers. The pressed samples were subjected to various electron
beam irradiation dose. The results indicated that, flexural strength, impact strength and modulus of elasticity increase with
increasing the polymer ratio in the mix composition. It was found that the water absorption and thickness swelling percentages
of rice straw fiber polystyrene composites decrease with increasing the polystyrene content in the same composition, while
its values for rice straw polyvinyl alcohol composites improve. These are attributed to hydrophobic and hydrophilic characteristics
of the tow composites. The improvement of physico-mechanical properties of both composites with the increase of electron beam
irradiation dose are probably attributed to randomly initiated chain reactions, which started by the reactive centers created
by electron beam. These observations were confirmed by IR spectrometer and SEM studies. 相似文献
363.
A number of factors persist to constrain the non-timber forest products (NTFPs) market and, by extension, its potential to contribute meaningfully to livelihood development and poverty reduction objectives. To better utilise the potential of NTFPs, it is important to have a better understanding of the key factors governing the success and failure of NTFPs trade. This paper reports on the market constraints and socio-economic factors that influence trade in five top-priority NTFPs within the tropical lowland rainforests of south-west Nigeria. The NTFPs investigated were bush mango (Irvingia gabonensis), African walnut (Plukenetia conophora), chew-stick (Massularia acuminata), fever bark (Annickia chlorantha) and bush pepper (Piper guineense). Field data were collected in 10 villages located within and around Omo and Shasha forest reserves using a household questionnaire survey. The results showed that seasonality, poor transport, lack of storage facilities and market information were the four main constraints influencing marketing and trade in the NTFPs. In addition, the level of education, gender (sex), household income, ethnicity, distance to the market and access to roads significantly influenced market knowledge and information among households involved in the trade of NTFPs. There is need to improve on the limited source of NTFPs information, enhance skills for product transformation, build innovative storage facilities, and develop the process of domestication and integration in traditional land-use systems. 相似文献
364.
SUMMARY Forty cats with hyperthyroidism were treated using 200 to 300 (typically 250) mBq of orally administered 131I. Thirty-six cases (90%) were successfully treated, as assessed by resolution of clinical signs and reduction In plasma thyroxine concentrations to normal or reduced values after treatment. Although higher doses of 131I appear to be required when the radioisotope is administered orally rather than Intravenously, a less stressful administration procedure and greater availability of therapy capsules offer useful advantages for treating thyrotoxic cats. 相似文献
365.
366.
Ismail MM 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2005,52(7):354-358
The pharmacokinetic properties of ceftriaxone were investigated in 10 goats following a single intravenous (i.v.) and intramuscular (i.m.) administration of 20 mg kg(-1) body weight. After i.v. injection, ceftriaxone serum concentration-time curves were characteristic of a two-compartment open model. The distribution and elimination half-lives (t(1/2alpha), t(1/2beta)) were 0.12 and 1.44 h respectively. Following i.m. injection, peak serum concentration (C(max)) of 23.6 microg ml(-1) was attained at 0.70 h. The absorption and elimination half-lives (t(1/2ab), t(1/2el)) were 0.138 and 1.65 h respectively. The systemic bioavailability of the i.m. administration (F %) was 85%. Following i.v. and i.m. administration, the drug was excreted in high concentrations in urine for 24 h post-administration. The drug was detected at low concentrations in milk of lactating goats. A recommended dosage of 20 mg kg(-1) injected i.m. every 12 h could be expected to provide a therapeutic serum concentration exceeding the minimal inhibitory concentrations for different susceptible pathogens. 相似文献
367.
Basoglu A Sen I Sevinc M Simsek A 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(2):238-241
This study was performed to determine the concentrations of tumor necrosis factor (TNF) in the serum of neonatal calves with presumed sepsis and determine the correlation between serum concentrations of TNF and the severity and outcome of disease. Thirty-five sick calves < 30 days old that suffered from enteritis, respiratory disease, or both were considered suitable for inclusion in this study by satisfying clinical and laboratory criteria suggestive of septicemia. At admission, blood samples were collected from all calves to determine the prevalence of high concentrations of TNF. The clinical course and outcome of disease then were recorded. Of the 35 calves with presumed sepsis, 10 had high serum TNF concentrations. Scleral injection, weak or absent suckling reflex, sternal or lateral recumbency, unresponsive or comatose state, and death rate of calves with high serum TNF concentration were greater than those values for calves without high serum TNF concentration. Calves with high serum TNF concentration had significantly lower mean IgG (P < .001), globulin (P < .0001), and calcium (P < .0001) concentrations; greater serum creatinine concentrations (P < .0001); and > or = 2+ toxic changes in neutrophils than did calves without high serum TNF concentrations. Mean values for packed cell volume, band neutrophil count, and venous Pco2 were significantly (P < .007) higher in the group of calves with high serum TNF concentration. Results of this study indicate that serum TNF concentration is correlated with clinical criteria of sepsis in neonatal calves. A close association was apparent between disease severity and serum TNF concentrations in this group of calves with presumed septicemia. 相似文献
368.
369.
Effect of Boll Age and Harvesting Period on Fiber Properties of Egyptian and Upland Cotton Cultivars
The physical properties of cotton fibers for the successive age of development were studied in three different periods. Three cultivars of Egyptian and Upland cottons; Giza 75, McNair 220 and Tamcot H. 37 , were planted at Fayoum Experiment Farm, Faculty of Agriculture in 1984 season. Fiber properties were studied on samples obtained from five successive stages of boll development in three different periods. Data obtained revealed that fibers from both Egyptian and Upland cultivars showed substantial increment in micronaire reading up to 42 days after flowering. Micronaire reading showed a trend similar to fiber maturity percentage in studied cultivars.
Within each period, fibers tended to be stronger, more extensible, tougher and have higher stiffness with the increase in boll age. The rate of increment in the successive boll ages for fiber strength and elongation characters were markedly higher in the Egyptian cultivar than the American upland cultivars, especially in the younger boll ages. Fiber length was slightly affected by the environment growth conditions. However, the increase in fiber length was progressive from the age of 21 days up to the age of 35 days. 相似文献
Within each period, fibers tended to be stronger, more extensible, tougher and have higher stiffness with the increase in boll age. The rate of increment in the successive boll ages for fiber strength and elongation characters were markedly higher in the Egyptian cultivar than the American upland cultivars, especially in the younger boll ages. Fiber length was slightly affected by the environment growth conditions. However, the increase in fiber length was progressive from the age of 21 days up to the age of 35 days. 相似文献
370.
Observations were made on the abundance and survival of Haemonchus placei, Cooperia punctata and Oesophagostomum radiatum infective larvae from cattle faecal pats exposed at various times of the year in north Queensland wet tropics. Pats exposed in the hot, wet season yielded abundant larvae on herbage. In the dry season, although low numbers of infective larvae were usual, considerable numbers were produced under conditions of heavy dews on dense herbage. Irrespective of season of deposition of pats, the resulting larvae persisted generally for not longer than 10 to 12 weeks, and in large numbers for only 2 to 6 weeks. The findings suggest that prevention of contamination in the wet season, and in the dry season when light rainfalls are accompanied by heavy dews on dense herbage, will result in low levels of larval infestation on herbage. Rotational grazing in the area is suggested as a means of worm control. 相似文献