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131.
大豆活性肽对肉鸡肠道黏膜结构的影响 总被引:4,自引:0,他引:4
将500只1日龄艾维茵肉鸡随机分为5组,即分别饲喂添加80、120和200g/kg大豆活性肽的日粮、添加抗生素的日粮和基础日粮。在28、49日龄取材,采用组织切片及组织化学染色方法检测肉鸡十二指肠、空肠、盲肠的绒毛长度与隐窝深度比值、杯状细胞数量,观察大豆活性肽对肉鸡肠道黏膜结构的影响,进而研究大豆活性肽对肉鸡消化能力的作用。结果表明:日粮中添加80 ̄120g/kg的大豆活性肽能够提高肉鸡生长初期的肠道杯状细胞数量,增加肉鸡肠道绒毛长度/隐窝深度比值。 相似文献
132.
Feline vaccine‐associated sarcomagenesis: Is there an inflammation‐independent role for aluminium? 下载免费PDF全文
M. A. AbdelMageed P. Foltopoulou E. A. McNiel 《Veterinary and comparative oncology》2018,16(1):E130-E143
Aluminium has been found in feline vaccine‐associated sarcomas. In this study, we investigated the potential for aluminium to contribute directly to tumourigenesis. Our results indicated that an aluminium hydroxide adjuvant preparation was cytotoxic and mutagenic in human‐Chinese hamster ovary (CHO) hybrid cells in vitro. Moreover, CHO cells deficient in DNA double strand break (DSB), but not single‐strand break (SSB), repair, were particularly sensitive to aluminium exposure compared with repair proficient cells, suggesting that aluminium is associated with DSBs. In contrast to CHO cells, primary feline skin fibroblasts were resistant to the cytotoxic effects of aluminium compounds and exposure to an aluminium chloride salt promoted cell growth and cell cycle progression at concentrations much less than those measured in particular feline rabies vaccines. These findings suggest that aluminium exposure may contribute, theoretically, to both initiation and promotion of tumours in the absence of an inflammatory response. 相似文献
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Anna Kakehashi Akihiro Hagiwara Norio Imai Min Wei Shoji Fukushima Hideki Wanibuchi 《Journal of toxicologic pathology》2015,28(1):27-32
In the present study, in continuation of our previous experiment in order to investigate the mode of action (MOA) of ethyl tertiary-butyl ether (ETBE) hepatotumorigenicity in rats, we aimed to examine alterations in cell proliferation, that are induced by short-term administration of ETBE. F344 rats were administered ETBE at doses of 0, and 1,000 mg/kg body weight twice a day by gavage for 3, 10, 17 and 28 days. It was found that the previously observed significant increase of P450 total content and hydroxyl radical levels after 7 days of ETBE administration, and 8-OHdG formation at day 14, accompanied by accumulation of CYP2B1/2B2, CYP3A1/3A2, CYP2C6, CYP2E1 and CYP1A1 and downregulation of DNA oxoguanine glycosylase 1, was preceded by induction of cell proliferation at day 3. Furthermore, we observed an increase in regenerative cell proliferation as a result of ETBE treatment at day 28, followed by induction of cell cycle arrest and apoptosis by day 14. These results indicated that short-term administration of ETBE led to a significant early increase in cell proliferation activity associated with induction of oxidative stress, and to a regenerative cell proliferation as an adaptive response, which could contribute to the hepatotumorigenicity of ETBE in rats. 相似文献
136.
H-Y抗血清的制备及检测研究 总被引:1,自引:0,他引:1
选用8 ~12 周龄纯系的 B A L B/ C 母鼠, 用同日龄的 B A L B/ C 公鼠采取皮肤移植和脾细胞注射2 种方式免疫, 制备 H Y 抗血清, 经精子微量细胞毒性试验, 筛选抗血清。皮肤移植5 只小鼠中只有1 只产生较好的抗血清, 脾细胞注射的4 只小鼠都能产生较好的抗血清, 产生抗血清的小鼠占55 % 。抗血清与昆明鼠正常8cell 早期桑椹胚培养5 ~6 、18 和24 h 后, 退化率达433 % , 经 X2 检验差异不显著( P > 005) , 符合自然性比例。 相似文献
137.
扁蓿豆与紫花苜蓿杂交育种研究 总被引:2,自引:0,他引:2
受辐射突变育种理论的启示,辐射二倍体扁蓿豆(Melissutus ruthenicus)和四倍体苜蓿(Medicago sativa)种子,提高属间远缘杂交不育的亲和性,获得成功后经过品比试验,区域试验和生产试验,最终育成正反交两个异源四倍体苜蓿新品种(1976~1992),即龙牧801苜蓿(Melilotoides ruthenicus(L.)Sojak×Medicago sativaL.cv.Longmu No.801)和龙牧803苜蓿(Medicago sativa L.×Melilotoides ruthenicus(L.)Sojok cv.Longmu No.803),并于1992年经全国牧草品种审定委员会审定登记。其中801苜蓿抗寒(-35℃~-45℃)、耐盐碱性(pH 8.16)较强,再生性好,在松嫩、三江平原地区每年刈割2次,干草产量6000~8000 kg/hm2;803苜蓿抗寒(-35℃~-45℃)、耐盐碱性(pH 8.16~8.4)较强、再生性好、丰产性好,在松辽平原和东部白浆土均可种植,每年刈割2-3次,干草产量10000~12000 kg/hm2。现将辐射处理后,突变体认定、杂交、杂种识别和育种方法及其过程加以论述。旨在和同行进行交流探讨,以期为苜蓿育种工作的发展有所裨益。 相似文献
138.
ie-1和lef-1基因dsRNA表达元件转染及转化细胞对家蚕核型多角体病毒增殖的抑制 总被引:1,自引:2,他引:1
通过RNAi介导可以抑制病毒增殖,将相应的RNAi元件通过转基因转入宿主有可能使宿主对病毒产生一定的抗性。根据家蚕核型多角体病毒(BmNPV)基因组中的病毒复制必需基因ie-1、lef-1设计相应的RNA干扰区段,并构建相应的转基因载体转入家蚕BmN细胞中,瞬时表达结果显示转染了转基因RNAi载体的BmN细胞均对BmNPV有一定的抑制作用。IE dsRNA在病毒滴度为10-4时有抑制作用,在病毒滴度为10-5时有比较好的作用;LEF dsRNA则在病毒滴度为10-5时有抑制作用,在病毒滴度为10-6时有较好的抑制作用。通过转基因及G418筛选后,转基因IE dsRNA细胞在病毒滴度为10-4显示出一定的抑制作用,在病毒滴度为10-5表现了明显的抑制作用;而转基因LEF dsRNA细胞在病毒滴度为10-5有一定的抑制作用,但只维持了一个时段。 相似文献
139.
Canine Haematopoietic Chimerism Analyses by Semiquantitative Fluorescence Detection of Variable Number of Tandem Repeat Polymorphism 总被引:1,自引:0,他引:1
Hilgendorf I Weirich V Zeng L Koppitz E Wegener R Freund Junghanss C 《Veterinary research communications》2005,29(2):103-110
Canine models are successfully applied to the study of haematopoietic stem cell transplantation (HSCT). Monitoring of haematopoietic donor/recipient chimerism is of major significance in detecting and quantifying engraftment or graft rejection of the donor-derived haematopoietic cells after transplantation. Radioactive analyses of polymorphic microsatellite markers are commonly used for chimerism analyses. We describe an improved, non-isotopic method that is based on the analysis of microsatellite markers in donor and recipient cells using capillary electrophoresis and fluorescence detection. Artificial mixtures of donor and recipient DNA that were generated from peripheral blood mononuclear cells from dog leukocyte antigen-identical siblings were used to analyse the sensitivity of the assay. DNA from dogs that had received HSCT were also analysed in order to demonstrate the feasibility of the method in vivo. For chimerism analyses, six different microsatellite loci were systematically amplified using fluorescent PCR primer. The fluorescent polymerase chain reaction products were separated by capillary electrophoresis using POP4 on a 310 ABI Prism Genetic Analyzer. After electrophoresis, fluorescence signals were automatically sized and quantified using GeneScan software. The method described provides an accurate assessment of haematopoietic chimerism in the canine model with significantly reduced hands-on time compared to conventional gel electrophoresis. 相似文献
140.