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61.
This study aimed to examine 25OHD3 concentration in the fluid of follicular and follicular lutein cysts of sows in comparison with preovulatory follicles as well as immunolocalize vitamin D metabolic enzymes (CYP27B1 and CYP24A1) and determine their protein abundances in the cyst wall. We have shown for the first time that 25OHD3 level in the fluid of both cyst types was significantly lower than in preovulatory follicles. Furthermore, we have demonstrated CYP27B1 and CYP24A1 protein immunolocalization and abundance in follicular and follicular lutein cysts. The abundance of protein for both metabolic enzymes was decreased in ovarian cysts when compared to preovulatory follicles. We propose that altered VD metabolism in ovarian cyst might associate with their formation in sows.  相似文献   
62.
为评价口蹄疫病毒A型竞争ELISA(cELISA)抗体检测试剂盒在流行病学调查中的应用前景,对2017年从福建省三明市采集的336份黄牛、奶牛、羊和猪血清样品,用A型cELISA抗体检测试剂盒进行抗体检测。结果显示,92份黄牛血清、92份羊血清、92份猪血清、60份奶牛血清的A型抗体阳性率分别为13.04%、11.96%、20.65%、86.67%。从上述4种血清中,各挑选10份血清(阴性、阳性各5份)共40份,采用口蹄疫病毒液相阻断ELISA(LPB-ELISA)抗体检测试剂盒进行验证。结果显示:cELISA检测为阳性的20份血清中,用LPB-ELISA检出阳性19份;cELISA检测为阴性的20份血清中,用LPB-ELISA检出阴性17份;两种方法的κ值为0.8,总符合率为90.00%。结果表明,A型cELISA试剂盒与LPB-ELISA试剂盒的符合率和一致性均较高,可用于口蹄疫流行病学调查和血清学监测。  相似文献   
63.
试验旨在构建一种更安全有效的新型免疫去势DNA疫苗,通过选取下丘脑-垂体-性腺轴(hypot halamic-pituitary-gonadal axis,HPG)的上游调控基因吻素1(KISS1)和促性腺激素释放激素(GnRH)作为靶标,借助2A肽的自剪切功能,引入平衡致死系统代替抗性基因筛选流程,成功将GnRH和KISS1转入非抗性筛选质粒pVAX-asd中,酶切验证和测序对比验证目的基因的插入方向和序列完全正确。重组质粒转染HeLa细胞,反转录后扩增目的基因结果显示,重组质粒在真核细胞内能够正常转录,保证重组质粒在导入机体后能够正常表达,从而引起特异性免疫反应。将构建成功的质粒转入减毒的猪霍乱沙门氏菌C500中,获得可直接口服免疫的活载体疫苗,酶切和测序结果表明,双表达重组质粒成功导入工程菌中。将活菌疫苗在体外连续传代50次,选取0、2、5、10、20、30、40、50代的菌株进行稳定性研究,生长曲线检测结果表明,工程菌在体外连续传代50次的过程中,其生长特性无明显变化,且与减毒猪霍乱沙门氏菌C500的生长特性一致,未因携带质粒发生明显变化;同时将各代菌液扩增沙门氏菌标志基因(invA)和毒力基因(crp),结果表明多次传代后工程菌仍然具有沙门氏菌的特性,其减毒特性也无变化。各代菌液质粒酶切验证显示,多次传代并不影响质粒的稳定性,重组双表达质粒能够在沙门氏菌C500中维持正常拷贝功能。综上所述,该重组质粒和工程菌疫苗均具有良好的稳定性,可直接应用于动物免疫去势的研究。  相似文献   
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All feces produced during 24 h were collected from five pigs and cortisol and immunoreactive cortisol metabolites (CICM), and IgA were quantified. Within pigs, the concentrations of CICM and IgA varied extensively between random samples obtained from a single fecal dropping, and deviated in most cases significantly from the true concentration measured in total fecal output (CV 6.7-130%). The CICM and IgA contents varied considerably (CV 8.1-114%) within and between individual fecal droppings from the same pig compared to the total fecal excretion. In conclusion, single random samples could not be used to reliably quantify the total fecal concentration or excretion of CICM or IgA in pigs. Analyses of all feces collected during shorter periods than 24 h did not provide an accurate estimate of the daily excretion of CICM. Thus, the concentration of stress sensitive molecules in random single fecal samples as an indicator of animal welfare should be interpreted with prudence.  相似文献   
68.
Potato common scab caused by the actinobacterium Streptomyces scabiei is characterized by the formation of corky lesions on tubers that reduce their marketability. Management of common scab is very complex and often ineffective under various environmental conditions. Using potato varieties that are more resistant to common scab remains one of the most efficient strategies to control this disease. However, very little is known about the factors associated with resistance to common scab. Somaclone RB9 regenerated from thaxtomin A-habituated potato Russet Burbank calli produced tubers more resistant to common scab than the original variety. Comparison of the RB9 tuber proteome with that of Russet Burbank using label-free quantitative proteomic analysis revealed changes in the accumulation of defence-related proteins from the patatin and lipoxygenase (LOX) families, which are involved in the metabolism of lipids, and of two miraculins of the Kunitz-type protease inhibitors family. The implication of LOX during common scab infection was studied using synchronized minitubers developed from leaf-bud cuttings. S. scabiei infection stimulated the accumulation of LOX in both Russet Burbank and RB9 minitubers, but this accumulation was intensified in RB9 minitubers. Infection also increased LOX activity in Russet Burbank and RB9 minitubers. However, LOX activity measured in noninfected RB9 minitubers was similar to that of infected Russet Burbank minitubers, indicating endogenous activation of LOX activity in RB9 minitubers. We discuss how increased LOX abundance and activity in the somaclone RB9 may contribute to improving tuber defence against common scab.  相似文献   
69.
三棱栎种子特性与其致濒关系初步分析   总被引:3,自引:0,他引:3  
周元 《种子》2004,23(1):13-15
三棱栎是云南特有种,国家二级保护植物,主要分布在澜沧、沧源、孟连、西盟、勐腊等县.研究表明,其萌发温度在20~35℃范围内,萌发率在5.3%~9.1%之间.4个不同分布地和8种温度条件下萌发率差异不显著.本文认为三棱栎濒危的主要原因是:(1)三棱栎果实结实率低;(2)果实的特殊形状,不利于传播;(3)幼苗缺乏竞争力.针对三棱栎的濒危现状和原因,提出了三棱栎的一些保护措施.  相似文献   
70.
A. A. Markov Rolling Forecast Method is presented in this paper according to the dynamic characteristics of the estate business system. Test results reveal that the system quantitative forecast could be realized on the basis of previous samples, which provide a direction of the rational management in estate business. Concerning sample molding analysis and Markov Rolling Forecast Method, this paper gives a corresponding conclusion of analytic research quantitatively in order to demonstrate the formation of factors working in estate business activities and its systematic logistic connotation. Markov Rolling Forecast Method can be applied not only to short-term prediction but long term one as well, provided when the market is rather stable with no significant change during a regular period of time and when the rolling times of the state transition matrix are fairly enough.  相似文献   
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