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81.
Oxidative stress and bovine liver diseases: role of glutathione peroxidase and glucose 6-phosphate dehydrogenase 总被引:1,自引:0,他引:1
This article summarizes the different types of free radicals, antioxidants and the effect of oxidative stress on the activities of glutathione peroxidase and glucose 6-phosphate dehydrogenase in bovine liver diseases. A growing body of evidence suggests that the formation of reactive oxygen species is a common occurrence associated with most if not all disease processes. The overall importance of reactive oxygen species to the progression and severity of various disease states varies greatly depending on the conditions and whether the disease is acute or chronic. Free radical researches in animals are in progress and further investigations are needed to establish the involvement of reactive oxygen species in diseases affecting different animal species and the pathology they produce. 相似文献
82.
Jun Sasaki Megumi Uehara Itaru Sato Hiroshi Satoh Yoshitaka Deguchi Hiroyuki Chida Masahiro Natsuhori Takahisa Murata Kenji Ochiai Kumiko Otani Keiji Okada Nobuhiko Ito 《Animal Science Journal》2019,90(9):1333-1339
To study the effect of ionizing radiation on thyroid glands, 66 Japanese Black cattle residing in the restricted area of the Fukushima Daiichi Nuclear Power Plant in 2013–2017 were pathologically examined. There were no clinical symptoms of thyroid disease in these cattle. Three cases of goiter and seven of atrophy were found in two among the four farms examined. Cases of goiter exhibited normal morphological structure without mass or nodule formation in thyroid glands. Cellular atypia or capsular invasion of the follicular epithelium was absent. The estimated integrated dose of external radiation in goiter cases ranged from maximum 797 mSv to minimum 24 mSv. All lobules in the seven atrophic thyroid glands were affected, but pathological findings, such as inflammatory cell infiltration or stromal fibrosis, were not observed. The estimated integrated dose of external radiation in atrophic thyroids ranged from maximum 589 mSv to minimum 8 mSv. Immunohistochemical analysis of anti‐nitroguanosine and the TUNEL method in goiter and atrophic thyroid glands did not reveal any positive findings. The present study indicates that there was no significant relationship between a radiation effect and pathological findings in any thyroid glands. 相似文献
83.
Itaru Sato Jun Sasaki Hiroshi Satoh Masahiro Natsuhori Takahisa Murata Keiji Okada 《Animal Science Journal》2019,90(8):1090-1095
Blood and urine were compared to clarify which is a better sample for estimating the concentration of radioactive cesium in muscles of live cattle. The most probable concentration of 137Cs in muscles was 21.0 times that in blood, and the error of this estimation was 28%. The concentration of 137Cs in blood was estimated accurately using urine samples. The estimation error did not increase so much (33%), even when the concentration of 137Cs in muscles was estimated using urine samples. On the other hand, the maximum volume of blood that can be collected with one syringe is 50 ml, whereas it is easy to collect 1,000 ml of urine. It took at least 360 min to confirm that a cow meets the legal standard by inspecting 50 ml of blood. However, with 1,000 ml of urine, a 20 min measurement time was sufficient for this purpose. This difference in the required measurement time is critically important for practical use. In addition, urine can be collected by farmers themselves, whereas the blood collection requires a veterinarian. Therefore, urine is a more convenient and practical sample for estimating the contamination level of live cattle with radioactive cesium. 相似文献
84.
畜禽注水肉的卫生检验与卫生处理 总被引:1,自引:0,他引:1
注水肉系指不法经营者无视国家的屠宰法规和食品卫生法规 ,对畜 (牛、猪、兔等 )、禽 (鸡、鸭 )等在宰前或宰后人为地采用某种手段器械(注射器、皮管、压力泵 )通过畜禽口腔、食道、肛门直肠、动脉血管、皮下等部位注射入一定量的水分 ,以此增加畜禽重量 ,使胴体、肌肉、内脏的含水量剧增 ,达到饱和状态。近几年来 ,畜禽注水肉多见于牛肉、猪肉、鸡鸭肉 ,尤其在农贸集市非常普遍 ,已引起广大消费者和有关部门的关注。1畜禽注水的途径与方法1.1宰前活体注水灌食强行固定猪体灌水姿势 ,用皮管塞入口腔或肛门注入水 ,注水量可占体重的20%… 相似文献
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86.
为了测定H1N1亚型猪流感病毒(swine influenza virus,SIV)对小鼠的致病性,本试验对A/swine/Guangdong/2/2012(H1N1)株SIV HA基因进行克隆及遗传分析,并将SIV尿囊液经鼻腔感染6周龄BALB/c小鼠,观察感染后小鼠的一般状况、器官系数和组织病理学变化,在病毒感染后第1、3和7天使用荧光定量PCR测定小鼠肺脏、脾脏、脑组织中7种细胞因子mRNA的表达量,研究其对小鼠的致病特性。结果显示,该病毒属于经典SIV,病毒经鼻腔感染后可引起小鼠活动减少、采食量降低,但无咳嗽和死亡;病理组织学变化为肺间隔较正常组织明显增厚,毛细血管明显扩张充血,周围肺泡腔呈代偿性肺气肿;小鼠肺脏、脾脏组织样本中IFN-α、IFN-β、IP-10、IL-1β、TNF-α、IRF-3和IL-10 mRNA含量在感染后第3天均显著升高(P<0.05),而脑组织样本中IL-1β和IL-10在小鼠攻毒后第3和7天均显著上调(P<0.05)。 相似文献
87.
LIU Bin GUO Jun Wudubala MA Yue-jun XIN Lei-yong ZHAO Cun-fa LI Yu-rong YIN Jun 《中国畜牧兽医》2017,44(4):994-1000
In order to extend the anagen of cashmere goat hair follicles and increase the production of cashmere,this study was performed with artificially shorten the daylight time among Arbas White cashmere goats. Skin tissue sections from cashmere goats were collected to compare the morphologic changes between artificial daylight and natural daylight,and immunohistochemical method was used to study the hair follicle cell proliferation and important protein expression in related signaling pathways. The results showed that strong cell proliferation occurred in cashmere goat hair follicle cells during artificial daylight,plenty of cytokeratin 15 (K15) positive signals were distributed in the outer root sheath,β-catenin protein was actively expressed in hair matrix and root sheath, indicating that the hair follicles were in the anagen growth phase;Meanwhile,cashmere goat hair follicles under natural daylight were in telogen with weak signals. Above all prove that short photoperiod played an important role in promoting hair follicle growth,the artificial short photoperiod could change hair follicle growth cycle and make hair follicles earlier enter to the anagen growth phase,causing a variety of typical gene expressions during hair follicle growth. 相似文献
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90.
纳罗克非洲狗尾草种子产量因子与产量的通径分析 总被引:3,自引:1,他引:3
采用多因素裂区试验设计,通过大样本相关、通径和逐步回归分析后,结果表明,纳罗克非洲狗尾草Setaria sphacelata cv. Narok的6个种子产量因子对种子产量的直接贡献大小排序为:x4(单位长度小花数)>x6(千粒重)>x1(花序长)>x2(单位面积生殖枝数)>x3(单位长度小穗数)>x5(单位长度种子数),说明提高单位长度小花数、千粒重和花序长是最有效提高纳罗克非洲狗尾草种子产量的途径,其次提高单位长度小穗数、单位长度小花数和单位面积生殖枝数。 相似文献