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31.
海克军 《四川畜牧兽医学院学报》2006,4(1):206-208
大学生就业难是社会普遍关注的焦点问题之一。大学生就业中的伦理道德缺失不容忽视。要解决这一问题,除学校加强道德教育、企业提升自身魅力外,根本在于大学生自身的觉悟与个人素养的提高。 相似文献
32.
Genetic characterization of canine rotavirus isolated from a puppy in Korea and experimental reproduction of disease. 总被引:3,自引:0,他引:3
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Yoo HH Lee M Chung HJ Lee SK Kim DH 《Journal of agricultural and food chemistry》2007,55(18):7620-7625
The effects of citrus flavonoids on P-glycoprotein (P-gp)-mediated drug efflux were examined in human intestinal Caco-2 cells. The cellular accumulation of rhodamine-123 was measured using 10 citrus flavonoids for preliminary screening. Among the flavonoids tested, diosmin significantly increased the accumulation of rhodamine-123 in Caco-2 cells. In the bidirectional transport of digoxin, diosmin increased the apical-to-basal (A-to-B) transport but decreased the basal-to-apical (B-to-A) transport in both concentration- and time-dependent manners. The digoxin transport ratio (B-A/A-B) was estimated to be 2.3 at a concentration of 50 microM of diosmin, which was significantly lower than the 15.2 found in the control. The apparent Ki values for P(app,A-B) and P(app,B-A) were 16.1 and 5.7 microM, respectively. These results demonstrated that diosmin effectively inhibited the P-gp-mediated efflux in Caco-2 cells. Diosmin is one of the main components in citrus fruits, and the intake of food supplements containing this compound may potentially increase the absorption of drugs able to act as P-gp substrates. The clinical relevance of this interaction should be further evaluated using in vivo experiments. 相似文献
37.
Arts MJ Grun C de Jong RL Voss HP Bast A Mueller MJ Haenen GR 《Journal of agricultural and food chemistry》2007,55(17):7010-7014
Although hardly any polyunsaturated fatty acids (PUFAs) are present in the endproduct, the ingredients used for the production of beer contain a high concentration of PUFAs, such as linolic and linolenic acid. These compounds are readily oxidized, resulting in the formation of lipid-derived products that reduce the taste and quality of beer enormously. During mashing relatively high amounts of PUFAs are exposed to atmospheric oxygen at a relatively high temperature. This makes mashing a critical step in the brewing process with regard to the formation of lipid-derived off-taste products. F1 phytoprostane (PPF1) changes in antioxidant capacity and monohydroxy fatty acids (OH-FAs) were used as markers for the detection of oxidative damage to fatty acids during mashing. The pattern of OH-FA formation indicates that enzymatic oxidation of PUFAs is more important than nonenzymatic oxidation during the mashing process. Nevertheless, substantial nonenzymatic radical formation is evident from the increase of specific OH-FAs and PPF1s. It was found that a low oxygen tension reduces oxidative damage and gives a high antioxidant capacity of the mashing mixture. This indicates that mashing should be done under low oxygen pressure. 相似文献
38.
White spot syndrome virus (WSSV), a rod-shaped double-stranded DNA virus, is an infectious agent causing fatal disease in shrimp farming around the globe. Within shrimp populations WSSV is transmitted very fast, however, the modes and dynamics of transmission of this virus are not well understood. In the current study the dynamics of disease transmission of WSSV were investigated in small, closed populations of Penaeus monodon and Penaeus vannamei. Pair cohabitation experiments using PCR as a readout for virus infection were used to estimate transmission parameters for WSSV in these two species. The mortality rate of contact-infected shrimp in P. monodon was higher than the rate in P. vannamei. The transmission rate parameters for WSSV were not different between the two species. The relative contribution of direct and indirect transmission rates of WSSV differed between the two species. For P. vannamei the direct contact transmission rate of WSSV was significantly lower than the indirect environmental transmission rate, but for P. monodon, the opposite was found. The reproduction ratio R0 for WSSV for these two species of shrimp was estimated to be above one: 2.07 (95%CI 1.53, 2.79) for P. monodon and 1.51 (95%CI 1.12, 2.03) for P. vannamei. The difference in R0 between the two species is due to a lower host mortality and hence a longer infectious period of WSSV in P. monodon. 相似文献
39.
Jin Ju Lee Jae Hong Kim Dae Geun Kim Dong Hyeok Kim Hannah Leah Simborio Won Gi Min Man Hee Rhee Jong Hwan Lim Hong Hee Chang Suk Kim 《Veterinary microbiology》2014
The pathogenic mechanisms of Brucellosis used to adapt to the harsh intracellular environment of the host cell are not fully understood. The present study investigated the in vitro and in vivo characteristics of B. abortus betaine aldehyde dehydrogenase (BetB) (Gene Bank ID: 006932) using a betB deletion mutant constructed from virulent B. abortus 544. In test under stress conditions, including osmotic- and acid stress-resistance, the betB mutant had a lower osmotic-resistance than B. abortus wild-type. In addition, the betB mutant showed higher internalization rates compared to the wild-type strain; however, it also displayed replication failures in HeLa cells and RAW 264.7 macrophages. During internalization, compared to the wild-type strain, the betB mutant was more adherent to the host surface and showed enhanced phosphorylation of protein kinases, two processes that promote phagocytic activity, in host cells. During intracellular trafficking, colocalization of B. abortus-containing phagosomes with LAMP-1 was elevated in betB mutant-infected cells compared to the wild-type cells. In mice, the betB mutant was predominantly cleared from spleens compared to the wild-type strain after 2 weeks post-infection, and the vaccination test with the live betB mutant showed effective protection against challenge infection with the virulent wild-type strain. These findings suggested that the B. abortus betB gene substantially affects the phagocytic pathway in human phagocytes and in host cells in mice. Furthermore, this study highlights the potential use of the B. abortus betB mutant as a live vaccine for the control of brucellosis. 相似文献