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21.
Kazuki NAKASHIMA Itoko NONAKA Shigehiko MASAKI Makoto YAMAZAKI Hiroyuki ABE 《Animal Science Journal》2004,75(4):353-360
The effect of heat stress on protein oxidation and myofibrillar proteolysis in chick myotubes was investigated. Myotubes were incubated at 37 or 41°C for 6 and 24 h. Protein carbonyl content, as an index of protein oxidation, increased more at 41°C than at 37°C for 6 and 24 h incubations. Nτ‐methylhistidine release as an index of myofibrillar proteolysis also increased more at 41°C than at 37°C for 6 and 24 h incubations. Proteasome activity also increased more under those same conditions. Calpain and cathepsin D but not B + L activities showed a greater increase at 41°C than at 37°C for 24 but not the 6 h incubation. These results indicate that heat stress increases protein oxidation and proteasome activity, resulting in an increase in myofibrillar proteolysis for short‐term incubation and, for long‐term incubation, it increases calpain, proteasome and cathepsin D activities, finally accelerating myofibrillar proteolysis in chick myotubes. 相似文献
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Kunio SUGAHARA Mako MATSUMOTO Motoko YAMADA Fumiaki YAOSHIZAWA Yutaka KARASAWA 《Animal Science Journal》2004,75(5):431-434
In order to determine the role of the cecum on energy use in growing chickens, metabolizability of the dietary energy and energy expenditure were examined in the week following bilateral ligation and washing out of the cecum. Apparent metabolizable energy (AME) values were 14.30 and 13.69 kJ/g air‐dry matter for sham‐operated and cecally ligated chickens, respectively. These values were found to be significantly different (P < 0.05). Although AME intake and fasting heat production were decreased by cecal ligation, the distribution of AME (measured as fasting and feeding heat production, as well as heat increment and energy retention, as a proportion of AME intake) was not affected. These results suggest that the cecum helps chickens extract AME from corn‐soybean type diets with little, if any, effect on AME use, based on the present study of growing chickens in the week following cecal ligation. 相似文献
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硒和维生素E在热应激猪自由基代谢中的作用 总被引:8,自引:0,他引:8
在平均温度为 (34.89± 5 .6 2 )℃的猪舍内 ,选择 10 0日龄长大二元杂交商品生长猪 (去势公猪 ) 4 0头 ,随机分为 4组 ,通过日粮添加不同水平的硒 (Se)和维生素 E(VE)作为对照组、低水平组、中水平组和高水平组 ,测定与自由基代谢有关的血清丙二醛 (malondialdehyde,MDA )含量、超氧化物歧化酶 (superoxide dismutase,SOD)、谷胱甘肽过氧化物酶 (glutathione- peroxidase,GSH- Px)活性。结果表明 ,补充 Se和 VE 可降低 (P<0 .0 5 )或显著降低 (P<0 .0 1)血清MDA含量 ;升高 (P<0 .0 5 )或显著升高 (P<0 .0 1)血清 SOD和 GSH- Px活性 ,从而证明 Se和 VE可减少热应激猪体内自由基的数量 ,缓解猪热应激时的自由基损伤 ,提高猪抗热应激的能力 相似文献
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定性和定量分析一批兽药硫酸黏菌素可溶性粉中的未知添加物。照《中国兽药典》2010年版一部对该批检品用微生物检定法进行含量测定时,发现该样品的抑菌圈为虚圈,用薄层色谱鉴别该样品,未显示与标准品溶液一致的主斑点,怀疑该样品中有处方外非法添加物。采用超高效液相色谱-四级杆-飞行时间质谱(UHPLC-Q/TOF MS)对该样品进行筛查,发现疑似添加物,并使用液相色谱-二极管阵列检测(HPLC-DAD)法进行了双重确证和含量测定。该样品中非法添加物确证为磺胺氯达嗪和甲氧苄啶,添加量分别为58.5 mg/g和13.4 mg/g。本研究通过建立筛查方法为监管部门提供技术支撑,通过分析非法添加物的可能原因为打击兽药处方外非法添加提供了思路。 相似文献
25.
A comparison of two sources of methionine supplemented at different levels on heat shock protein 70 expression and oxidative stress product of Peking ducks subjected to heat stress 下载免费PDF全文
L. Guo R. Li Y. F. Zhang T. Y. Qin Q. S. Li X. X. Li Z. L. Qi 《Journal of animal physiology and animal nutrition》2018,102(1):e147-e154
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Genome‐Wide Identification of MicroRNAs Responsive to High Temperature in Rice (Oryza sativa) by High‐Throughput Deep Sequencing 下载免费PDF全文
J. Li L.‐Q. Wu W.‐Y. Zheng R.‐F. Wang L.‐X. Yang 《Journal of Agronomy and Crop Science》2015,201(5):379-388
MicroRNAs (miRNAs) are known to play important roles in plant growth and stress response. Heat stress is a severe abiotic stresses by adversely affecting plant growth and yield. To identify heat‐responsive miRNAs at the genome‐wide level in rice (Oryza sativa), we constructed two small RNA libraries from young panicles treated or not with heat conditions. Ion torrent sequencing of the two libraries identified 294 known miRNAs and 539 novel miRNAs. Differential expression analysis showed that 26 miRNAs were downregulated and 21 miRNAs were upregulated in response to heat stress. Among them, five heat‐responsive miRNAs, including miR162b, miR529a‐p5, PC‐5P‐62245‐9, miR171b and miR169n, were validated by quantitative real‐time polymerase chain reaction. A total of 44 target genes of the differentially expressed miRNAs were predicted. These target genes are most significantly overrepresented in the cell growth process. The results demonstrated that rice miRNAs play critical roles in the heat stress response. This study opens up a new avenue for understanding the regulatory mechanisms of miRNAs involvement in the heat stress response in rice. 相似文献
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引进优良的外来树种可以丰富本国或本地区林业建设的树种资源,增加木材产量和林产品的种类。通过对引进的美国东部7个脂松种源进行试验,得出更适宜栽植区的种源。在树高方面,较好的4个种源依次为MIDC(Dickenson County,Michigan)、MNCNF(Chippewa National Forest,Minnesota)、MIMC(Manistee County,Michigan)和WIOC(Oneida County,Wisconsin);2004年高生长较好的4个种源依次为WIOC、MIDC、MIMC和MNCNF;2005年高生长较好的4个种源依次为MIDC、MIMC、MNCNF和WIOC;地径较好的4个种源依次为MIDC、WIOC、MIMC、MNCNF。该4个种源间各项生长指标差异不显著;在保存率方面,7个种源间差异不明显。 相似文献