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81.
为探究多鳞白甲鱼幼鱼日粮中最佳碳水化合物添加类型,以葡萄糖、麦芽糖、糊精、玉米淀粉及纤维素5种碳水化合物为糖源,分别配制5种日粮,对多鳞白甲鱼幼鱼进行了为期56 d的养殖实验。结果显示,(1)生长及饲料利用率方面,麦芽糖组的终末体重、特定生长率、饵料系数以及蛋白质效率等指标最佳,纤维素组最差。(2)体成分方面,纤维素组全鱼粗脂肪水平最低,粗灰分水平显著高于麦芽糖组,麦芽糖组及纤维素组肌糖原含量最低,糊精组肝糖原含量最低。(3)主成分分析表明,C16:0、SFA、MUFA和PUFA比例对肝胰脏脂肪酸比例产生主要影响,其中,C16:0和SFA比例在麦芽糖组显著提高,MUFA比例在糊精组显著提高,而PUFA在纤维素组显著提高;C18:1n-9和MUFA比例对肌肉和脂肪组织总体脂肪酸组成产生主要影响,二者比例在麦芽糖组显著提高。(4)血清生化指标方面,麦芽糖组及纤维素组谷丙转氨酶活性、麦芽糖组谷草转氨酶活性显著较高,葡萄糖组及纤维素组碱性磷酸酶活性、球蛋白含量较高,而血糖含量反之。(5)抗氧化能力方面,麦芽糖组肝胰脏过氧化氢酶、总超氧化物歧化酶、谷胱甘肽过氧化物酶活性最高,纤维素组丙二醛含量最... 相似文献
82.
为更加有效地进行育种理论研究和提高小麦育种成效,对‘鲁麦13’的培育思路、优异特性和育成品种进行了总结分析。从1996—2018年,以‘鲁麦13’为亲本,共有中国科学院、中国农科院和9省共57家育种单位育成品种77个。这些品种通过国家审定17次,通过山东、河北、江苏、安徽、河南、山西、陕西、新疆、甘肃、湖北、天津、北京审(认)定103次,截至2016年累计推广2512.13万hm2。‘鲁麦13’作为新一代骨干亲本,对山东和全国的小麦育种和生产,做出了重大贡献。 相似文献
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84.
Denise M. Lindley BS DVM John T. Hathcock DVM MS William W. Miller DVM MS M. Nina DiPinto VMD 《Veterinary radiology & ultrasound》1988,29(5):209-212
Following head trauma, the left globe of a Red Tail Hawk showed demonstrable indentation on palpation. Recurrent anterior chamber collapse and reformation dependent on head position was the most significant clinical finding. A fracture of the scleral ossicles in the caudal portion of the scleral ring was identified in the rostrocaudal radiograph of the skull. Conservative management of the fracture resulted in phthisis bulbi. Fractured scleral ossicles have been shown radiographically in the enucleated globe but have not been previously demonstrated in the eye of the living bird. 相似文献
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86.
Seventy-five dogs that showed a fear response to fireworks participated in a double-blinded, placebo-controlled clinical trial to assess the efficacy of a homeopathic remedy for the alleviation of their behavioural signs. Dogs were randomly assigned to one of two treatments; the homeopathic treatment or the placebo treatment. At the baseline assessments the owners identified the behavioural signs of fear that their dogs normally displayed in response to fireworks, rated their frequency and intensity, and assessed the global severity of their dog's responses. These measures were repeated at the final assessment and owners also completed weekly diaries for the length of the trial. There were significant improvements in the owners' rating of 14/15 behavioural signs of fear in the placebo treatment group and all 15 behavioural signs in the homeopathic treatment group. Both treatment groups also showed significant improvement in the owners' rating of the global severity of their dog's responses. However, there was no significant difference in the response seen between the two treatment groups. 相似文献
87.
88.
Rhulani Makhuvele Kenn Foubert Nina Hermans Luc Pieters Luc Verschaeve Esam Elgorashi 《The Onderstepoort journal of veterinary research》2022,89(1)
Aflatoxins are potent hepatotoxic and carcinogenic secondary metabolites produced by toxigenic fungi. The present study investigated the protective effect of methanolic leaf extracts of Monanthotaxis caffra (MLEMC) against aflatoxin B1-induced toxicity in male Sprague-Dawley rats. The rats were randomly divided into 6 groups of 8 animals each. Five groups were administered orally for seven days with three different concentrations of MLEMC (100 mg/kg, 200 mg/kg and 300 mg/kg), curcumin (10 mg/kg) or vehicle (25% propylene glycol). The following day, these groups were administered 1 mg/kg b.w. of aflatoxin B1 (AFB1). The experiment was terminated three days after administration of AFB1. Group 6 represented untreated healthy control. Serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatinine and liver histopathology were evaluated. Methanolic leaf extracts of M. caffra decreased the levels of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and creatinine in the sera of rats as compared with the AFB1 intoxicated group. Co-administration of MLEMC improved the histological characteristics of the hepatocytes in contrast to the AFB1 treated group, which had mild to severe hepatocellular injuries including bile duct proliferation, bile duct hyperplasia, lymphoplasmacytic infiltrate and fibrosis. Extracts of M. caffra were beneficial in mitigating the hepatotoxic effects of AFB1 in rats by reducing the levels of liver enzymes and preventing hepatic injury. 相似文献
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90.
Spatial and temporal variations in soil respiration in relation to stand structure and soil parameters in an unmanaged beech forest 总被引:1,自引:0,他引:1
Soil CO2 efflux (soil respiration) plays a crucial role in the global carbon cycle and efflux rates may be strongly altered by climate change. We investigated the spatial patterns of soil respiration rates in 144 measurement locations in a 0.5-ha plot and the temporal patterns along a 300-m transect in the 0.5-ha plot. Measurements were made in an unmanaged, highly heterogeneous beech forest during 2000 and 2001. We investigated the effects of soil, roots and forest stand structure on soil respiration, and we also assessed the stability of these spatial patterns over time. Soil temperature alone explained between 68 and 95% of the temporal variation in soil respiration; however, pronounced spatial scatter of respiration rates was not explained by soil temperature. The observed spatial patterns stayed remarkably stable throughout the growing season and over 2 years. The most important structural parameter of the stand was the mean diameter at breast height of trees within a distance of 4 m of the measurement locations (m-dbh4), which explained 10-19% of the variation in soil respiration throughout the growing season. Among the soil chemical parameters, carbon content (bulk as well as dissolved) and magnesium content explained 62% of the spatial variation in soil respiration. The final best model combining soil, root and stand structural parameters (fine root biomass, soil carbon content, m-dbh4 and soil water content) explained 79% of the variation in soil respiration, illustrating the importance of both biotic and abiotic factors. 相似文献