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71.
Kweon CH Kwon BJ Woo SR Kim JM Woo GH Son DH Hur W Lee YS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(9):961-964
Porcine epidemic diarrhea virus (PEDV) is the causative agent of neonatal diarrhea in piglets, which causes high mortality rates. In this study, the immunoprophylactic effects of chicken egg yolk immunoglobulin (Ig Y) against PEDV were investigated in neonatal pigs. Ig Y was found to reduce the mortality in piglets after challenge exposures. The field application of Ig Y also revealed significant differences in survival rates of piglets given Ig Y, as compared with placebo or control. The results in this study indicated that Ig Y against PEDV could be an alternative way of supplementing prophylactic measures like colostral antibodies from sows. 相似文献
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Kunimasa Kawabe Nguyen Thi Ngoc Truc Bui Thi Ngoc Lan Le Thi Thu Hong Masatoshi Onuki 《Journal of General Plant Pathology》2006,72(6):355-359
A quantification system for huanglongbing pathogen using a competitive polymerase chain reaction method and image-analyzing
software were developed to obtain precise results. Significant differences in the quantity of pathogen were thus determined
in leaves of two citrus cultivars commonly cultivated in southern Vietnam. Less pathogen-related DNA was detected from the
tissue of citrus cultivars that are believed to be more tolerant than susceptible cultivars. The quantification system will
be used in studies on pathogen proliferation and movement inside citrus tissue. 相似文献
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To compliment the current subirrigation systems used for production of potted plants, a nutrient-flow wick culture (NFW) system was developed and compared with other subirrigation systems, such as an ebb and flow culture (EBB) system and a nutrient-stagnant wick culture (NSW) system in relation to their system characteristics and plant growth. Kalanchoe (Kalanchoe blossfeldiana cv. New Alter) was cultivated in a 6 cm pot for 10 weeks in each subirrigation system. The water-absorption pattern of the medium, water content of the medium, water loss, algal growth, salt-buildup and plant growth under various culture systems were observed. The water contents of medium under the NFW and EBB systems showed fluctuations from 30 to 40% and from 50 to 60% (by volume), respectively, whereas the water content under the NSW system gradually increased to over 40% without fluctuation. Relative to other systems, the water loss in the NFW system was 50–70% due to the reduction in the evaporation from the surfaces of the trough and medium. Algae appeared in the NSW system because the nutrient solution was always stagnant in the trough, while it was not observed under the NFW system. The dissolved oxygen in the nutrient solution was the highest during the irrigation period and the salinity in the medium was the lowest in the NFW system. With regard to system characteristics, the NFW system was simple, water-saving and efficient. In addition, the growth of kalanchoes in the NFW system was similar to those in the NSW and EBB systems at an irrigation frequency of five times a day. 相似文献
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Water shortage has become a major agricultural concern, and “The Sustainable Water Resources Research Program” in Korea is currently addressing this problem through the development of treatment systems for reclaiming wastewater and the assessment of human health risks associated with its reuse. Through this program, started in 2001, many studies have examined various water resources. Reclaiming wastewater is one way to alleviate water-shortage pressures, and one of the major potential uses of reclaimed water is irrigation. However, the main concern with reusing reclaimed wastewater is the increased likelihood of human contact that might result in exposure to pathogens and increased health risks. Relatively few studies have examined the toxic risks using reclaimed wastewater for irrigation in rice paddy fields. This study provides an overview of methods for quantitative microbial risk assessment and toxic risk assessment of heavy metal concentrations developed in the previous studies that can be applied to the evaluation of rice paddy fields irrigated with reclaimed wastewater in South Korea. 相似文献
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合成了3个新的锰-超氧化物歧化酶(Mn-SOD)模拟物Mn(L-Leu)2(1),Mn(L-Val)2·3/2HCl(2)和Mn(L-Phe)2·HCl(3)(L-Leu=L-亮氨酸,L-Val-L-缬氨酸和L-Phe=L-苯丙氨酸).用元素分析、红外光谱对模拟物进行了表征.并用 NBT 光还原法检测了模拟物的SOD活性.结果表明3个模拟物均具有相对较高的类似于 SOD 催化超氧阴离子自由基(O2·-)歧化活性,抑制率为 50%时配合物的浓度,即一个活性单位值 IC50值分别为 0.311、0.274 和 0.378μmol/L.有望成为具有良好应用前景的新型 SOD 模拟物抗拟增产剂而应用于农业生产中. 相似文献