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1. This study was conducted to determine the effects of heat stress on fearfulness, leucocyte components, oxidative stress and lipid peroxidation in two commercial broiler strains, Cobb (C) and Ross (R). 2. At 36 and 37 d of age birds were exposed to 38 +/- 1 degree C for 3 h. Rectal temperatures, duration of tonic immobility (TI), haematocrit values, proportions of leucocyte components (heterophil, lymphocyte, basophil, eosinophil, monocyte), malondialdehyde (MDA) concentrations and antioxidant enzyme activities (CAT, SOD, GPx) of all the birds were determined, before and after heat treatment. 3. Rectal temperatures increased and haematocrit values decreased in birds exposed to heat stress. Heat stress caused a significant increase in heterophil/lymphocyte and in basophil ratios. 4. Exposing birds to heat stress increased duration of TI, suggesting heat-stressed birds tended to be more fearful. 5. Heat stress resulted in a significant Genotype x Treatment interaction for MDA concentration. CAT, SOD and GPx activities; MDA concentrations in heat-stressed R strain birds were greater than in heat-stressed C strain birds.  相似文献   
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A new monocyclic triterpene ester (1) was isolated from the rhizomes of Iris germanica from Turkey. Structure elucidation of compound (1) was carried out by the combined application of HMQC, HMBC, DEPT, COSY and NOESY experiments and named as iristectorone K.  相似文献   
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Ecballium elaterium fruit juice is used for the treatment of sinusitis in Turkish folk medicine. The aim of this study was to increase the yield of cucurbitacin B, an anti-inflammatory compound previously isolated in various organs of E. elaterium, through tissue culture techniques. Higher yields of cucurbitacin B (1.126%) were obtained from the first subculture calluses from stem nodes in the presence of benzyl adenine (BA; 1 mg/l) and naphtalene acetic acid (NAA; 0.1 mg/l) in comparison with the yields obtained from plant material (0.01%).  相似文献   
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The serum concentrations of serotonin and lipids--triglycerides, total cholesterol, low density lipoprotein, high density lipoprotein and very low density lipoprotein--were determined in 18 normal dogs and 23 dogs diagnosed as aggressive on the basis of interviews with their owners and an assessment of their behaviour with reference to a canine overt aggression chart. The serum serotonin levels in the aggressive dogs were significantly lower than in the normal dogs (P<0.01), but the differences in serum lipids between the two groups were not statistically significant.  相似文献   
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Owing to unique structure and characteristics of carbon nanotubes, much more are attracted attentions since they were discovered. In recent years, carbon nanotubes have been successfully synthesized by various methods. Especially, highly aligned carbon nanotubes were grown by chemical vapor deposition (CVD) and the oriented growth of carbon nanotubes became realized, resulting in many applications of carbon nanotubes and researches on them. In the work, the methods and mechanisms of orientation growth of carbon nanotubes were reviewed, and it was analyzed and discussed that different methods influenced on the process of growing carbon nanotubes. Simultaneously, it was emphatically analyzed that catalyst particles affected on orientation growth of carbon nanotubes during their growth.  相似文献   
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Essential oils of peppermint Mentha piperita L. (Lamiaceae), which are used in flavors, fragrances, and pharmaceuticals, were investigated for their antimicrobial properties against 21 human and plant pathogenic microorganisms. The bioactivity of the oils menthol and menthone was compared using the combination of in vitro techniques such as microdilution, agar diffusion, and bioautography. It was shown that all of the peppermint oils screened strongly inhibited plant pathogenic microorganisms, whereas human pathogens were only moderately inhibited. Chemical compositions of the oils were analyzed by GC and GC/MS. Using the bioautography assay, menthol was found to be responsible for the antimicrobial activity of these oils.  相似文献   
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Zosima absinthifolia (ZA) extracts and the coumarins (+)-columbianadin and (-)-deltoin were evaluated for their potential hepatoprotective and antiinflamatory effects in a CCl(4)-induced hepatotoxicity assay in rats and by the inhibition of TNF-α production on LPS-stimulated THP-1 macrophages, respectively. Both the ZA extracts and the coumarins showed hepatoprotective activity confirmed by monitoring the ALT/AST levels and by histopathological examination. The antiinflamatory activity, proved by the inhibition of TNF-α production, was found to be higher for the n-hexane root extract than for coumarins, suggesting synergic potential of the extract. The concentration of (-)-deltoin and (+)-columbianadin in extracts was determined by HPLC analysis.  相似文献   
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沿江圩区主要农作物病虫草害演替呈现以下特点 :种类增加 ,不断出现新的病虫为害 ;危害期拉长 ,发生程度加重 ;突发性病虫暴发成灾 ;螟虫危害趋于复杂化等。为此制定了近期与长远期综合治理措施 ,及时有效地控制其危害  相似文献   
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