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991.
A. Flåøyen B. Bratberg A. Frøslie H. Grønstøl W. Langseth P.G. Mantle A. Von Krogh 《Veterinary research communications》1997,21(2):137-148
Flåøyen, A., Bratberg, B., Frøslie, A., Grønstøl, H., Langseth, W., Mantle, P.G. and Von Krogh, A., 1997. Further studies on the presence, qualities and effects of the toxic principles from Narthecium ossifragum plants. Veterinary Research Communications, 21 (2), 137-148One calf was dosed during one day with an aqueous extract from 3.0 kg (wet weight) of Narthecium ossifragum and another was dosed on the same day with the insoluble plant residue. The concentrations of serum creatinine and magnesium increased only in the calf dosed with the aqueous extract, while the activity of glutamate dehydrogenase increased only in the serum of the calf dosed with the plant residue, so differentiating the nephrotoxic and hepatotoxic principles as water-soluble and water-insoluble compounds, respectively.One calf was dosed with 30 g (wet weight) N. ossifragum flower stems per kg live weight during one day and another was dosed with 30 g (wet weight) N. ossifragum leaves per kg live weight on the same day. The serum creatinine and urea concentrations and also the activities of glutamate dehydrogenase, aspartate aminotransferase and -glutamyltransferase in the serum increased in the calf dosed with the flower stems, whereas there was only a slight temporary increase in the creatinine concentration in serum from the calf dosed with the leaves. However, histopathological examination of the kidneys of the calf dosed with the flower stems revealed severe tubular necrosis and degeneration. It therefore appears that both the toxic principles are present in the flower stems of N. ossifragum rather than in its leaves.The serum creatinine concentration was significantly increased in a non-ruminating calf dosed with an aqueous extract from 32 g (wet weight) N. ossifragum per kg liveweight during one day, showing the intrinsic nephrotoxicity of the plant. 相似文献
992.
C. Campion P. Massiot F. Rouxel 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(8):725-735
This study investigated the relationships between pathogenesis, types of symptoms and in vitro production of cell-wall degrading enzymes by P. violae, P. sulcatum and P. ultimum. The three pathogens, considered as the three Pythium species principally responsible for cavity spot on carrot roots, secreted only low levels of fatty acid esterases activity, suggesting they have limited ability to degrade suberin in the walls of the outer cell layers of carrot tissues. Among the enzymes that degrade cell-wall polysaccharides, only pectate lyases and cellulases were produced by P. violae, and these were produced late and in small amounts: the symptoms caused by P. violae were limited and typical of cavity spot. Conversely, P. ultimum caused maceration of tissues, and secreted polygalacturonases and -1,4-glucanases earlier and in larger amounts than P. violae. P. ultimum also produced a large diversity of proteins and cellulase isoenzymes. Although secreting all the monitored enzymes in higher quantity than the two previous species, P. sulcatum was responsible for only typical limited symptoms of cavity spot, with a brown colouring. The role of plant reactions induced in response to early pectinolytic enzyme production by P. sulcatum may account for this apparent inconsistency.Died on April 11, 1997 相似文献
993.
994.
硒对高温胁迫下辣椒叶片抗氧化酶活性的调节作用 总被引:27,自引:3,他引:27
硒是人体或动物抗氧化反应必需的微量元素。为了研究硒在高等植物体内的生理功能, 将辣椒两个品种‘中椒7号’和‘耐湿椒’盆栽在不同含硒量的草炭蛭石混合基质中, 现蕾后分次将植株移入人工气候室进行高温胁迫处理(25℃ 2 h→35℃ 2 h→40℃ 2 h) , 然后取叶片测定各指标。结果表明: 施硒( ≤0.9 mg·kg- 1 ) 提高了叶片的总叶绿素含量, 同时, 可以分别使GPX和POD 活性提高11.5 倍和63.6% , 对SOD和CAT则表现为负效应。另外, 硒还使叶片MDA含量比不加硒对照降低36%。在不同品种的辣椒体内, 硒的作用存在一些差异, 但总体的趋势相同。以上结果说明硒对高温胁迫下辣椒叶片抗氧化酶活性有重要的调节作用, 并有利于提高辣椒植株的耐热性。 相似文献
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996.
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998.
选择隔离饲养至20日龄的健康雏鸭120只,随机分为4组,Ⅰ组为对照组,皮下注射0.5mL/只灭菌生理盐水,Ⅱ、Ⅲ、Ⅳ组分别皮下注射0.5mL/只1∶5稀释的鸡源、鹅源和鸭源新城疫病毒SPF胚液,并分别置于25℃隔离环境下饲养与观察。分别于感染后4、8、12、16d每组随机抽取雏鸭7只颈静脉放血致死,采集心、肝、脾、肺及肾组织,制成10%的组织匀浆液,测定超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、丙二醛(MDA)及谷胱甘肽过氧化物酶(GSH-Px)的活性或含量,探讨异源新城疫病毒感染对雏鸭组织自由基代谢的影响。结果表明,感染异源新城疫病毒的雏鸭组织SOD、CAT、GSH-Px活性和MDA含量变化不同,感染鸭源和鹅源新城疫病毒的雏鸭组织抗氧化酶的活性变化明显,而感染鸡源新城疫病毒的则变化不明显。这说明不同来源的新城疫病毒对雏鸭的感染性有一定差异。 相似文献
999.
甘氨酸铁对断奶仔猪血清氧化酶活力及生化指标的影响 总被引:4,自引:1,他引:3
试验研究甘氨酸铁对断奶仔猪抗氧化能力及血清生化指标的影响,并初步探讨其作用机理。选用180头体重7.5kg左右的"杜长大"三元杂交仔猪,分为6个处理组,分别饲喂0、30、60、90、120mg/kg甘氨酸铁和120mg/kg硫酸亚铁,试验期5周。结果表明:饲粮中添加甘氨酸铁,均不同程度的提高了血清中SDH、CAT、XOD和AKP的酶活,降低了血尿氮(SUN)、Ca和P含量。由此可知,甘氨酸铁可以影响仔猪机体抗氧化能力和血清生化指标,在一定程度上改善仔猪的生产性能。 相似文献
1000.
Tibbo M Jibril Y Woldemeskel M Dawo F Aragaw K Rege JE 《Tropical animal health and production》2008,40(8):657-666
Serum enzymes were studied in 163 apparently healthy goats from three indigenous goat breeds of Ethiopia. The effect of breed,
age, sex and season on alanine aminotransferase (ALT) / glutamic pyruvic transaminase (GPT), aspartate aminotransferase (AST)
/ glutamic oxalacetic transaminases (GOT), alkaline phosphatase (ALP) and acid phosphatase (AcP) levels was assessed. The
mean serum enzymes levels of the indigenous Arsi-Bale, Central Highland and Long-eared Somali goat breeds ranged from 14.0–20.2
iu L−1 for ALT/GPT, from 43.2–49.3 iu L−1 for AST/GOT, from 83.7–98.8 iu L−1 for ALP, and from 2.99–4.23 iu L−1 for AcP, were within the normal range for goats elsewhere. Breed had significant influence on AST/GOT values. Sex had significant
effect on ALT/GPT for Arsi-Bale goats with higher values in males than females. Age was significant on all serum enzymes studied
in the Arsi-Bale goats and on ALP in the Central Highland goats. Season had significant influence on all serum enzymes except
for ALT/GPT in the Arsi-Bale goats. The serum enzyme levels of these indigenous goat breeds can be used as normal reference
values for Ethiopian goat breeds adapted to similar agro-ecology and production system. 相似文献