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选用川楝子治疗鸡球虫病及其对机体免疫力影响的研究,通过测定用药前后球虫虫卵数量的变化,以及测定用药前后血清和胸腺、脾脏、法氏囊组织匀浆中NO、NOS、SOD、MDA含量,结果为川楝子组血清和胸腺、脾脏、法氏囊组织匀浆中NO、NOS、SOD、MDA含量都较球虫感染对照组差异显著(P0.05)或差异极显著(P0.01);川楝子组对鸡免疫器官胸腺、脾、法氏囊指数指数均较球虫感染对照组差异显著或差异极显著。说明川楝子治疗鸡球虫病效果明显,且能够促进鸡免疫器官的发育和增强机体的免疫力,为研究驱杀球虫中药对免疫功能的影响提供了一种可行性的方法。 相似文献
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为了探讨兔斯氏艾美耳球虫（E．stiedai）感染兔肝脏诱导型一氧化氮合酶（iNOS）活性和血清N0浓度变化以及NO对兔球虫的抑制或杀伤作用，以腹腔注射途径给予球虫感染家兔一氧化氮合酶（NOS）底物L-精氨酸（L-Arg）和iNOS抑制剂L-氮基胍（L-AG），对家兔球虫感染时肝脏iNOS活性、血清NO浓度、每克粪便的球虫卵囊数（OPG）、肝的剖检和镜下病变及其病变计分进行了研究。试验结果表明：①家兔感染E．stiedai后，肝匀浆的iNOs活性和血清中NO浓度逐渐升高，感染对照组、添加L-Arg组和添加L-AG组3组均在感染后第12天达到最高值，而后逐渐下降，于23d左右下降到感染前的水平；②L-Arg可增强iNOS的活性，促进体内大量生成NO，进而提高家兔对球虫的抑制作用，减轻球虫感染引起的病变；L-AG则降低iNOS的活性，使体内生成的NO减少，从而加重球虫感染引起的病变。结果提示：NO及iNOS确实参与了家兔E．stiedai的感染过程，并且NO在球虫感染过程中起到了抑制或杀伤兔球虫的作用。 相似文献
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近年来许多研究表明一氧化氮(NO)在抗寄生虫感染过程中发挥着重要的作用,其作用更多受到一氧化氮合酶(NOS)的影响。利用NO供体来模拟NO的活性是研究NO作用的一个重要手段。NO抑制寄生虫感染的机理十分复杂,既有直接作用,也有间接和免疫协同作用等多个作用。本文就NO的生物学特性、作用机制及其抗寄生虫感染的关系和影响因素等方面做一简要概述。 相似文献
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鸡球虫的免疫预防已有近80年的历史，20世纪20年代Tyzzer等发现鸡在自然感染球虫后可获得对再感染的高度抵抗力，表明鸡可对球虫产生免疫力。鸡球虫免疫是体液免疫、细胞免疫、局部免疫积极参与的综合免疫。 相似文献
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一氧化氮抗寄生虫感染的研究进展 总被引：4，自引：1，他引：3
一氧化氮 (NO)在寄生虫感染过程中具有抑制或杀伤寄生虫与对宿主机体产生病理损伤的双重作用。机体内 NO的产生及抗寄生虫作用受细胞因子严格调节 ,巨噬细胞经 IFN-γ等细胞因子或脂多糖 L PS刺激后能大量表达 i N-OS,产生的 NO对球虫、弓形虫、锥虫、疟原虫、肝片吸虫、血吸虫等均有杀伤作用 ,NOS抑制剂的阻断则进一步表明 NO在寄生虫感染中的重要作用。近年来 ,关于 NO抗寄生虫感染、作用机制、NO合酶抑制剂和细胞因子影响等的研究报道日渐增多。文章就有关研究进展进行了综述 相似文献
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为了揭示鸡柔嫩艾美耳球虫（E．tenella）病的免疫机制，试验从分子水平、细胞、亚细胞对人工攻毒病鸡特异性抗体、免疫细胞的动态变化及在抗球虫中的作用进行了探讨，试验结果如下：一是雏鸡感染E．tenella后，第6天即可在外周血液中检测出特异性IgG，于第18天达到峰值，第23天开始下降，第30天时降至感染后第7天的水平；二是揭示了雏鸡感染E．tenella后，鸡体IgG生成细胞的动态变化规律为：主要免疫器官胸腺、法氏囊、脾脏、盲肠扁桃体和盲肠局部的IgG生成细胞于第2天和第3天开始增殖，在第9天至第16天达到峰值，然后逐渐下降，盲肠扁桃体中的IgG生成细胞在第18天降至对照组水平，盲肠、脾脏和法氏囊中的IgG生成细胞数在第22天仍高于对照组，且差异显著。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献