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31.
AIM:To elucidate the molecular mechanisms of lipoic acid (LA) on redox regulation and digestive function in intestine of C57BL/6 mice fed high fat diet (HFD).METHODS:C57BL/6 mice were randomly assigned to one of three groups (n=8).The control group consumed an ordinary diet.The other two experimental groups were fed with a high fat diet, high fat plus 0.1% LA.After 6 weeks, the activities of digestive enzymes were examined.In order to evaluate the antioxidant status of the mice, superoxide dismutase (SOD), malondialdehyde (MDA), total antioxidant capacity (TAC) and reactive oxygen species (ROS) in intestinal homogenate were measured.To investigate the molecular mechanisms underlying the effects of LA, the gene expression profiles in intestine were examined using the GeneChip microarray system.RESULTS:A depressed antioxidant defense system, accompanied by digestive and absorptive function impairment, was observed in HFD-fed mice.These changes were partially restored in the LA-treated group.DNA microarray analysis of intestine showed that LA ingestion up-regulated the expression of genes related to free-radical scavenger enzymes, digestive enzymes and transporters.CONCLUSION:Treatment with LA improves redox homeostasis and the function of intestine in mice fed HFD.The mechanism may involve preventing oxidative stress by scavenging ROS directly and increasing those of free-radical scavenger enzymes gene expression indirectly. 相似文献
32.
G. LE TRAON S. BURGAUD & L. J. I. HORSPOOL 《Journal of veterinary pharmacology and therapeutics》2009,32(3):213-218
Long-term oral treatment with cimetidine is recommended to reduce vomiting in dogs with chronic gastritis. Despite this, few studies have specifically examined the plasma disposition and pharmacokinetics of cimetidine in dogs, particularly following repeated oral administration. The pharmacokinetics of cimetidine following oral administration as tablets was investigated in healthy dogs. Cimetidine was absorbed rapidly post-treatment ( t max = 0.5 h). A mean absolute bioavailability of 75% was calculated following a single oral administration of 5 mg cimetidine/kg body weight. After intravenous administration, a plasma half-life of 1.6 h was calculated. Repeated oral administration at the recommended dose rate and regime (5 mg/kg body weight three times daily) for 30 consecutive days did not lead to any accumulation of cimetidine in plasma. Food intake concomitant with oral administration of cimetidine delayed ( t max = 2.25 h) and decreased the rate and extent of absorption ( AUC ) by about 40%. Cimetidine was well absorbed in fasted dogs. Administration of food decreased the bioavailability of cimetidine by 40%. Cimetidine does not accumulate over time in plasma when administered long term to dogs. 相似文献
33.
TANG Lu PEI Yue-hong ZHANG Nan LE Wei-dong FAN Dong-sheng DENG Min ZHANG Jun 《园艺学报》2009,25(12):2441-2446
AIM: To explore the mutual effect of co-culture of wild-type astrocytes (ASC) and motor neurons VSC4.1 (VSC) on the respective ability to produce reactive oxygen species (ROS). METHODS: The inhibition rates of cell growth in ASC and VSC in co-culture or independent culture was detected after exposed to excitatory stimulus by MTT method. Real-time observation of ROS production by ASC and VSC labeled with Hoechst 33342 was detected by confocal microscopy under the conditions of co-culture or independent culture. RESULTS: Higher concentration of glutamate induced a higher inhibition rate in mixed cell growth than that in ASC alone, while lower concentration of glutamate induced a higher inhibition rate in mixed cell growth than that in VSC only. Real-time observation by confocal microscopy showed that ROS production by VSC under the condition of co-culture, which showed a notable increase at 15 min, was significant less than that in independent culture, which peaked at 5 min and was gradually decreased. ROS production by ASC in co-culture began to increase significantly at 10 min. CONCLUSION: Compared to independent culture, ASC reduces the resting ROS production by co-cultured with VSC, while ASC prolongs the duration of ROS production by VSC after exposed to excitatory stimulus. 相似文献
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35.
Rogelio AGUILAR‐AGUILAR Andrés MARTÍNEZ‐AQUINO Héctor ESPINOSA‐PÉREZ Gerardo PÉREZ‐PONCE DE LEÓN 《Integrative zoology》2014,9(3):328-339
As part of an ongoing inventory of the helminth parasites of freshwater fishes in Mexico, 570 individual fish were collected between Apr 2008 and Oct 2011 in 26 localities along the Cuatro Ciénegas region in Coahuila State, northern Mexico. Seventeen species of hosts, mostly corresponding to Nearctic freshwater elements, were studied. A total of 8324 individual worms were collected during this survey, representing 25 species of helminths, of which 9 were digeneans, 3 monogeneans, 3 acanthocephalans, 9 nematodes and 1 cestode. Most of the records in this checklist represent new host or locality records. The information provided in this checklist may be helpful for our understanding of the biodiversity and historical biogeography of this host–parasite system, because in the Cuatro Ciénegas region occur a Nearctic freshwater fish fauna, along with Neotropical and endemic elements, and from a biogeographical point of view, this may represent a transitional area. 相似文献
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37.
南海是金枪鱼类的重要分布区,开展南海金枪鱼类养殖潜在适宜区选划研究具有重要意义。南海金枪鱼类的主要种类为黄鳍金枪鱼 (
38.
Sophie JOIMEL Herv CAPIAUX Christophe SCHWARTZ Mickal HEDDE Thierry LEBEAU Ccile LE GUERN Johanne NAHMANI Cline PERNIN Sandrine SALMON Lucia SANTORUFO Batrice BCHET Jrme CORTET 《土壤圈》2018,28(2):215-226
Geogenic lead (Pb) is considered to be less bioavailable than anthropogenic Pb and exerts less effect on the soil fauna. However, Pb contamination in vegetables has been reported in the case of geogenic anomalies, even at moderate concentrations (around 170 mg kg–1). In this study, we investigated collembolan communities using both taxonomic- and trait-based approaches and observed fungal communities to assess the effects of a moderate geogenic Pb anomaly on collembolans and fungi in an urban vegetable garden soil. Results indicated that geogenic Pb indeed modified fungi communities and altered the functional structure of collembolan communities in garden soils. Although geogenic Pb presented low bioavailability, it affected soil fauna and vegetables similar to anthropogenic Pb. 相似文献
39.
Antimicrobial sensitivity testing of Australian isolates of Bordetella avium and the Bordetella avium-like organism 总被引:1,自引:0,他引:1
SUMMARY: The in-vitro sensitivity of 16 Australian isolates of Bordetella avium and 15 isolates of B avium -like organism to 11 antimicrobial agents or combinations of agents was determined using a microtitre plate system to establish minimal inhibitory concentrations. All the B avium isolates were sensitive to ampicillin but resistant to erythromycin, lincomycin, spectinomycin, sulphamethoxazole, trimethoprim, and lincomycin + spectinomycin. Most of the B avium isolates were sensitive to tetracycline and resistant to streptomycin and sulphadiazine. All the B avium -like isolates were resistant to ampicillin, erythromycin, lincomycin, spectinomycin, streptomycin, tetracycline, trimethoprim, and lincomycin + spectinomycin. Most B avium -like isolates were sensitive to sulphadiazine, sulphamethoxazole and trimethoprim-sulphamethoxazole. 相似文献
40.
多媒体技术在现代教学中应用广泛,成效也日益显著,在《动物微生物》教学中应用多媒体技术进行教学,既可丰富学生的理论知识,又能促进学生动手能力的提高。 相似文献