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51.
孕牛血清中早孕因子的分离纯化 总被引:2,自引:0,他引:2
采用DEAE-Sepharose(DEAE-琼脂糖凝胶)、CM-Sepharose(CM-琼脂糖凝胶)等离子交换层析、抗孕牛全血清IgG-Sepharose 4B亲和层析等技术,分离纯化妊娠4-5个月健康孕牛全血清中的早孕因子(EPF),用玫瑰花环抑制实验对各阶段产物EPF活性进行检测。结果表明,经层析过柱后的CM-ⅡA提取物有EPF活性。经SDS-PAGE银染显色证实它含有分子量为21、67、80KD的蛋白,实验结果支持21KD的多肽为主要EPF活性物成分。同时实验表明了亲和层析对进一步纯化EPF是可行的。 相似文献
52.
53.
为鉴定男性不育药和有些驱虫药对寄生蠕虫的不育作用,对培养在试管内的鸡蛔虫和卵胚,以及人工感染蛔虫的鸡分别进行了体内和体外试验。棉酚和硝基呋喃类的呋喃唑酮、呋喃西林、S_(73031)和S_(72055)均无抑制产卵和卵胚发育的作用,苯并咪唑类的丙硫咪唑、甲苯咪唑和噻苯咪唑以及吩噻嗪均有抑制产卵和卵胚发育的作用,它们的EMIC_(50)分别为0.006,1.326,0.029和0.052ppm。抑制产卵所需浓度远大于抑制卵胚发育所需浓度。吡喹酮和硫双二氯酚也不具有抑制产卵和卵胚成熟的作用。放线菌酮仅对试管内蛔虫有抑制产卵作用,但对体内蛔虫却无影响。 相似文献
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56.
自然感染日本血吸虫病耕牛血清循环抗原消长规律的研究 总被引:1,自引:0,他引:1
为了观察疫区自然感染日本血吸虫病耕牛血清循环抗原消长规律,本试验将血吸虫病非疫区的水、黄牛各10头,转运至安徽省血吸虫病疫区,接受为期8周的自然感染。用斑点酶联免疫吸附试验测定牛血清循环抗原。结果,水、黄牛血清循环抗原滴度均于自然感染第4周后明显上升,水、黄牛自然感染第8周的血清循环抗原最高滴度分为1∶10240和1∶5120,最低滴度则分别为1∶1280和1∶640,水牛循环抗原滴度高于黄牛。虫荷数与血清循环抗原滴度未见有相关性。 相似文献
57.
Michael H. Woodford 《Tropical animal health and production》2009,41(7):1023-1033
Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental
security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission
and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human
population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade
in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the
ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded
townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The
emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to
increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted
and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent
and its human, domestic and wild hosts is stressed. 相似文献
58.
鸡丘脑背外侧核前部与上纹状体、新纹状体、外纹状体及圆核和视顶盖有纤维交互投射;丘脑背外侧核后部与上纹状体、新纹状体及圆核和视顶盖有纤维交互投射,且与丘脑其他核团有较多的联系。 相似文献
59.
Research in control of tick-borne diseases and trypanosomosis, and their vectors, namely, ticks and tsetse flies respectively,
has been on going for decades. However, very little attention has been paid to the socio-economic factors that are likely
to influence the outcome of the interventions in the control of these diseases. Thus, this study was designed to investigate
these factors, mainly the intra-household factors influencing decision-making in the control of Vector-borne diseases in the
pastoralist areas of Uganda. These factors included: indigenous technical knowledge, household economic factors, and gender.
Both qualitative and quantitative methods were used in the collection and analysis of data. The tools used for data collection
included among others, participatory learning and action (PLA), and Case studies. The findings included the following: In
pastoralist households, a big proportion of the household budget was allocated to vector-borne diseases control. In the male-headed
households, men dominated decision-making on vector-borne diseases control, although the goals and priorities of men and women
in these households were not the same. Also, vector-borne disease control was predominantly by use of modern veterinary drugs,
and pastoralists treated sick cattle by themselves even in situations where there were veterinary personnel. 相似文献
60.