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1.
Two forms of vitellogenin were isolated by DEAE agarose ion-exchange chromatography from plasma of the tilapia, Oreochromis mossambicus. The monomers have apparent molecular masses of 200 and 130 kDa, as indicated by SDS-polyacrylamide gel electrophoresis (SDS-PAGE), and a total amount of phosphorus of 1.7 and 0.1%, respectively. Antibodies specific to the two forms, designated tVTG-200 and tVTG-130, were generated in rabbits and used to develop enzyme-linked immunosorbent assays (ELISAs) and in Western blot analyses of plasma and oocyte extract. SDS-PAGE of the oocyte extract showed a major protein band at 106.6, minor bands at 26.6, 24.2, and 23.7 kDa, and very faint bands at 83.4 and 17.5 kDa. Western blots of the oocyte extract revealed that the antiserum to tVTG-200 recognized strongly the protein bands at 24.2 and 23.7 kDa, and less strongly the bands at 25.1 and 22.6 kDa, whereas the antiserum to tVTG-130 recognized mainly the protein band at 106.6 kDa. The presence of both VTGs in untreated male tilapia was detected with the ELISAs using relatively high plasma volumes. Their presence in males was confirmed by VTG-like immunoreactive materials eluting from the ion-exchange column at the same positions as tVTG-200 and tVTG-130. The concentrations of the VTGs in males were several orders of magnitude lower than in vitellogenic females. Treatment of male tilapia with estradiol-17β (E2) induced both VTGs within 24h. After 7 days, tVTG-130 reached a maximum concentration in plasma, whereas tVTG-200 continued to increase. Our findings demonstrate that the two vitellogenins are biochemically distinct, possibly differentially regulated, and made by both sexes.  相似文献   
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Seven novel cell lines from canine histiocytic sarcoma (HS), three of which were disseminated cutaneous HS and four of which were synovial HS, were established. All of the established cell lines had the same morphological (by light and electron microscopic findings), cytochemical (alpha-naphthyl butyrate esterase-positive), and immunohistochemical (vimentin- and lysozyme-positive, and cyto-keratin-negative) characteristics as the original HS tumor cells. All of the established cell lines injected into nude mice subcutaneously produced solid tumors. Because the established cell lines also showed phagocytic and processing activities, the HS tumor cells appear to originate from the mononuclear phagocytic system cells, despite their differences in locations or organs.  相似文献   
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冬小麦蚰包,是亩产稳定800斤,高者可达1100斤以上的优良品种。本文系统总结了蚰包小麦十年创千斤的经验,论证了小麦生产过程中的阶段性、蚰包小麦创千斤的基本条件、群体动态结构及科学管理等问题。  相似文献   
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猪瘟病毒感染致外周免疫器官损伤的病理组织学观察   总被引:1,自引:0,他引:1  
将10头28日龄健康仔猪随机分成2组,其中感染组8头,对照组2头。感染组按1 mL/头颈部肌注猪瘟病毒(CSFV)石门株血毒(104TCID50/mL)进行人工感染,对照组不做任何处理。2 d后感染组仔猪体温升至40~41.5℃,稽留不退,而对照组体温正常。采集体温升高的仔猪扁桃体,运用RT-PCR方法检测,结果CSFV均为阳性,表明人工感染CSFV成功。分别于感染后4,7 d剖杀感染组和对照组仔猪各1头,剖解后观察各器官大体病变并采集脾脏和淋巴结等外周免疫器官制作石蜡切片,观察病理组织学变化;其余感染组仔猪分别于感染后13,16(2头),19,23,31 d自然死亡,死亡后按剖杀猪方法同样处理。组织学观察显示:随着病情的发展,感染组仔猪的脾脏和淋巴结的淋巴滤泡逐渐发生萎缩、甚至消失,脾脏的动脉周围淋巴鞘、淋巴结的副皮质区细胞亦逐渐减少坏死,即造成了T、B淋巴细胞的渐进性减少,而对照组无异常变化。结果表明:CSFV感染仔猪后,可引起脾脏淋巴结的淋巴细胞渐进性变性与坏死,造成免疫损伤。  相似文献   
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不同感染剂量MDRV对番鸭免疫反应和细胞毒性作用的影响   总被引:1,自引:1,他引:0  
用不同剂量番鸭呼肠孤病毒(MDRV MW9710株)感染8日龄番鸭后,通过检测血液中淋巴细胞对ConA、LPS的反应和NK细胞、细胞毒T细胞(CTL)的细胞毒性作用,探讨MDRV感染对番鸭免疫细胞功能和细胞毒性作用的影响。结果显示,不同感染剂量MDRV均会抑制番鸭血液淋巴细胞对ConA、LPS的增殖反应,降低NK细胞和CTL细胞的杀伤活性,且影响程度与剂量相关;同时感染番鸭生长缓慢,脾脏肿大,胸腺和法氏囊缩小。上述结果表明,MDRV感染能导致番鸭免疫抑制,且细胞免疫抑制程度与感染病毒量有关。  相似文献   
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The aim of the present study was to provide a method for evaluating bone toxicity induced by drugs in various bones in aged rats. Male Crl:CD (SD) rats at 46 weeks of age were administered 15 mg/m(2) body surface area of doxorubicin, which effects the growth plate in weanling rats, weekly for 9 weeks by intravenous injection, and the femur, sternum, humerus and tibia were examined histopathologically. In the doxorubicin-treated group, thinning of the growth plate was remarkably observed in the proximal tibia and humerus; however, these changes were not observed in other regions. In addition, the osteoclast number per bone perimeter in the proximal tibia was significantly higher than others in control aged rat. Thus, recognizing the various histological reactions related to the time of epiphyseal closure is important for evaluating bone toxicity in aged rats.  相似文献   
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试验旨在研究葡萄糖氧化酶(GOD)和乳酸菌制剂联合应用对肉鸡肠道形态及微生物菌群的影响.选取1日龄AA肉鸡1200只,随机分为4组,Ⅰ组为对照组,正常饮水;Ⅱ组为GOD组,在饮水中添加0.1% GOD;Ⅲ组为乳酸菌制剂组,在每只鸡饮水中添加1.5×105 CFU/(g·d)乳酸菌制剂;Ⅳ组为GOD与乳酸菌制剂联合应用组...  相似文献   
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以双季早稻超级稻淦鑫203为材料,设置34,36,38℃3个高温胁迫强度,1~5 d胁迫持续时间,于乳熟初期放入人工气候箱中进行高温处理,以同期田间自然温度为对照,研究了稻株倒二叶叶绿素含量、剑叶可溶性糖及可溶性蛋白质含量的变化。结果表明,淦鑫203在乳熟初期高温处理后,倒二叶叶绿素含量呈现先迅速升高后缓慢降低的特点,处理温度越高,天数越多,处理与对照间差异幅度越大;高温处理4 d后叶绿素含量恢复到对照水平。36℃和38℃高温1~2 d处理9 d后叶绿素含量较对照大幅降低,3~4 d处理6 d后叶绿素含量大幅降低。与对照相比,淦鑫203高温处理后剑叶中可溶性糖及可溶性蛋白质含量呈下降趋势,但可溶性糖及可溶性蛋白质含量胁迫指数均呈上升趋势。  相似文献   
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