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61.
Elettaria cardamomum is one of the most broadly used spices in Moroccan gastronomy. Its antimicrobial activity against both Gram-positive and Gram-negative bacterial species was demonstrated. Likewise, its toxicity was investigated on Swiss albinos mice. Daily, mice were treated orally with 0.003 and 0.3 mg during 7 days. Plasmatic markers and antioxidant defence systems were assessed and histological alterations were evaluated. A significant increase in creatine phosphokinase level was observed. The microscopic evaluation shows that E. cardamomum induce morphological perturbation in mice’s heart. The results show also an inhibitory effect of glyceraldehyde 3-phosphate dehydrogenase and an important increase in the level of thiobarbituric acid reactive substances, succinate dehydrogenase and catalase activities. Results show that E. cardamomum induces toxicity at 0.3 mg/g mouse and affect energy metabolism and oxidative stress. 相似文献
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本文阐述了四川油气田15年来聚合物钻井液的发展状况。对聚合物处理剂的优选、体系组分的优配、流变参数的优选优控作了简单的介绍。特别是使用复合离子型聚合物钻井液后,取得了明显的技术经济效益。 相似文献
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Cerebellar cortical contributions to eyeblink conditioned excitation have been examined extensively. In contrast, very little evidence exists concerning the role of the cerebellar cortex in eyeblink conditioned inhibition. In the current study, rats were given intraventricular infusions of the immunotoxin OX7-saporin to selectively destroy Purkinje cells throughout the cerebellar cortex following excitatory conditioning. After a 2-week postinfusion period, the rats were given reacquisition training. After reacquiring excitatory conditioning, the rats were trained in a feature-negative discrimination procedure to establish conditioned inhibition. Rats treated with OX7-saporin showed impaired reacquisition of excitatory conditioning and acquisition of conditioned inhibition. The results suggest that Purkinje cells play important, but different, roles in conditioned excitation and inhibition in rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Differential Age Effects on Attention-Based Inhibition: Inhibitory Tagging and Inhibition of Return.
Langley Linda K.; Vivas Ana B.; Fuentes Luis J.; Bagne Angela G. 《Canadian Metallurgical Quarterly》2005,20(2):356
The purpose of this study was to determine whether 2 forms of attentional inhibition, inhibition of return (IOR) and inhibitory tagging, are differentially affected by the aging process. The authors tested 24 younger adults (mean age = 22 years) and 24 older adults (mean age = 69 years) on a combined IOR and Stroop task (Vivas & Fuentes, 2001). As predicted, younger adults' performance was consistent with inhibitory tagging of objects at inhibited locations. Although older adults demonstrated intact IOR, there was no evidence of inhibitory tagging. The results suggest that age deficits in inhibition are selective. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Cefquinome sulfate behavior after intramammary administration in healthy and infected cows 总被引:1,自引:0,他引:1
Zonca A Gallo M Locatelli C Carli S Moroni P Villa R Cagnardi P 《Journal of dairy science》2011,94(7):3455-3461
Maintenance of adequate drug concentration at the site of infection is an important problem in mastitis antibiotic therapy, and the efficacy of intramammary β-lactams can be optimized by maintaining the drug concentration at the site of infection above the minimum inhibitory concentration (MIC) as long as possible. The most important pharmacokinetic and pharmacodynamic parameter for efficacy evaluation is time during which drug concentrations exceed the MIC (t > MIC). In this study, we assessed the pharmacokinetic profile of cefquinome (CFQ) after repeated intramammary administration in healthy cows and cows subclinically infected with Staphylococcus aureus as well as the MIC of Staph. aureus field strains. In addition, the degree of drug passage was investigated from udder to bloodstream by measuring systemic drug absorption in healthy and infected animals. Cefquinome concentrations were quantified by HPLC (UV-visible detection) in milk samples collected from quarters and from blood serum samples. The systemic drug absorption was negligible in healthy and subclinically infected animals (maximum concentration 0.09 ± 0.02 and 0.1 ± 0.01 μg/mL in healthy and subclinically infected animals, respectively). The MIC90 value for CFQ in Staph. aureus field strains (n = 20) was 0.24 μg/mL. The pharmacokinetic and pharmacodynamic evaluation, determined by t > MIC, showed an equal persistence of CFQ in all quarters, indicating an equivalent activity of the drug regardless of the pathological status of the udder. Moreover, with literature data regarding CFQ MIC, the t > MIC has been calculated for other bacterial species. 相似文献
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Chaohua Zhang Wenhong Cao Pengzhi Hong Hongwu Ji Xiaoming Qin & Jinfeng He 《International Journal of Food Science & Technology》2009,44(10):2042-2048
Peptic hydrolysate with angiotensin I-converting enzyme (ACE) inhibitory activity was prepared from Acetes chinensis . The 3 kDa ultrafiltration filtrates (UF-IV) of the desalted hydrolysate exerted a potent ACE inhibitory activity with IC50 being 0.67 mg mL−1 . The fractions with molecular weight located between 611 and 240 Da achieved a total percentage of 63.6% in the UF-IV, with a mean peptide length of about 5.6–2.1. Gastrointestinal digestions were simulated on the hydrolysate and UF-IV and addressed their effect on the ACE inhibitory activity. The ACE inhibitory activity of the UF-IV could survive or be maintained in active form by simulated gastrointestinal digestion. Furthermore, the UF-IV exerted potent antihypertensive effect after oral administrations were given to spontaneously hypertensive rats (SHR) at a dose of 900 mg kg−1 body weight. In conclusion, the UF-IV could serve as useful antihypertensive peptides in the prevention and treatment of hypertension and other associated disorders. 相似文献
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