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铅、镉及铅镉联合胁迫致雏鸡红细胞膜的损伤 总被引：1，自引：0，他引：1
150只7日龄公雏鸡分为10组,分别经口灌服或在体外培养红细胞中加入生理盐水、低浓度、中浓度及高浓度的铅、镉及铅镉混合溶液,研究铅、镉及铅镉联合对雏鸡红细胞膜Na+-K+-ATPase、Ca2+-Mg2+-ATPase活性的影响。结果表明:体内及体外红细胞铅、镉及铅镉联合染毒后,红细胞膜Na+-K+-ATPase、Ca2+-Mg2+-ATPase活性都有不同程度的降低(P0.01或P0.05),且呈明显的时间-剂量效应关系,中浓度联合染毒组与高浓度单独染毒组差异不显著(P0.05)。铅、镉、铅镉联合均对雏鸡红细胞膜有损伤作用,铅镉对红细胞膜的损伤有协同作用。 相似文献
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为研究促红细胞生成素(EPO)在铅镉联合胁迫致雏鸡贫血中的作用,选用60只7日龄公雏鸡,平均分为对照组、铅组、镉组和铅镉组,每日经口灌服染毒,分别于第1、3、7天染毒后,检测雏鸡血液学指标和网织红细胞数量,并进行骨髓象的观察及红细胞膜ATP酶活性、红细胞渗透脆性和血清EPO含量的检测。结果表明铅镉单独染毒使雏鸡发生贫血,网织红细胞数量先增加后降低,骨髓象增生先活跃后受抑制,红细胞膜Na+-K+-ATPase、Ca2+-Mg2+-ATPase活性降低,红细胞渗透脆性增加,血清EPO含量先增加后降低,铅镉联合染毒也表现出上述变化,且较单独染毒组变化明显(P<0.05或P<0.01)。本研究证实铅、镉单独及联合染毒均可引起雏鸡发生贫血,贫血类型主要为再生障碍性和溶血性贫血,且铅与镉存在显著的协同效应;EPO参与了铅镉联合胁迫致雏鸡的贫血作用。 相似文献
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将80只10日龄AA公鸡随机分为4组,分别经口灌服生理盐水、低浓度铅镉混合溶液、中浓度铅镉混合溶液和高浓度铅镉混合液,通过试剂盒检测鸡血液细胞因子IL-1β、IL-2和TNF水平,以研究铅、镉联合作用对雏鸡外周血液中细胞因子水平的影响。结果:铅镉联合染毒后,IL-1、IL-2水平显著降低(P<0.05或P<0.01),而TNF水平显著增高(P<0.05或P<0.01),且呈明显的时间-剂量效应关系,其中以高剂量联合染毒组变化最显著。表明铅、镉联合可以降低鸡的细胞免疫功能,进而引发机体免疫抑制。 相似文献
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本文主要介绍了畜禽摄入过量的重金属铅、镉,或被铅、镉污染的地因通过建立牧群、移场放牧、建立棚圈饲养而被动摄入过量,导致畜禽机体产生急性和慢性中毒,铅中毒畜禽出现消化障碍和神经机能紊乱反应,血液中嗜中性白细胞增多,点彩红细胞增多,X线检查腹部及骨有铅带,长骨骨骺有铅斑,血液铅浓度升高,可静脉注射6.6%的依地酸钠钙缓慢.镉中毒多为亚临床经过,镉在畜禽体内很难排出,存留期长,甚至终生.镉经消化道、呼吸道、皮肤吸收后,分布于红细胞和血浆中,通过红细胞膜与血红蛋白结合,与铜、铁、硒等微量元素相拮抗(颉颃),抑制骨髓的造血机能而造成贫血.严格控制镉排放,提高饲料中蛋白质比例,增加锌、硒供给量可限制镉沉着. 相似文献
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为了观察铅、镉及其联合对新生大鼠大脑皮质神经细胞的形态学影响,本试验通过对原代培养的新生大鼠大脑皮质神经细胞经提取、纯化和鉴定后,分九组进行单独或联合染毒,染毒时间为12 h,显微镜观察神经细胞形态并测量其胞体短直径和突起长度的变化.结果显示,与对照组相比,各试验组神经细胞密度降低,神经网络减少;各试验组神经细胞胞体短直径显著减小(P<0.05),突起长度显著变短(P<0.05);随铅、镉单剂量作用浓度的增加,神经细胞胞体短直径和突起长度有减小趋势,但组问差异不显著(P>0.05).与相应铅、镉单独染毒组比较.各铅镉联合染毒组神经细胞胞体短直径减小、突起长度变短更加明显,部分组间差异显著(P<0.05).结果表明,铅、镉作用浓度与神经细胞形态改变存在明显的剂量一效应关系,铅镉联合表现协同毒性效应. 相似文献
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铅镉联合暴露对大鼠肾脏的氧化损伤 总被引：5，自引：0，他引：5
采用饮水对大鼠进行铅(Pb)300 mg/L、镉(Cd)50 mg/L单独和联合(Pb+Cd)300 mg/L+50 mg/L染毒8周,通过检测肾脏皮质组织抗氧化指标和超微结构的变化来探讨铅镉对大鼠肾脏的毒性损伤及其机理.结果表明,Pb、Cd单独或联合染毒使肾脏皮质组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和还原型谷胱甘肽(GSH)含量显著或极显著低于对照组(P<0.05或P<0.01),以铅镉联合组降低幅度最大(P<0.01);3个染毒组丙二醛(MDA)含量显著或极显著高于对照组(P<0.05或P<0.01),联合组升高幅度最大而极显著高于单独染毒组(P<0.01).超微结构发现,铅镉染毒导致线粒体肿胀、膜损伤、嵴断裂或消失,联合组损伤程度重于单独染毒组.表明氧化损伤是Pb、Cd肾脏毒性的机制之一,其联合毒性表现为协同效应. 相似文献
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本研究旨在探讨Pb、Cd联合暴露对蛋鸡肝、肾组织中五种微量元素含量的影响。采用饮水对120只40周龄海兰褐蛋鸡进行铅(100 mg Pb/L)、镉(50 mg Cd/L)单独和联合(100 mg Pb/L+50 mg Cd/L)暴露8周。结果表明,铅、镉联合暴露对蛋鸡肝脏中铜、铁、锌、硒的影响呈协同效应,对锰的影响不明显;对肾脏中锰的影响呈协同效应,而对铜、铁、锌、硒呈一定的拮抗效应。铅镉在肝脏和肾脏中与微量元素之间存在复杂的相互作用。铅镉暴露引起家禽肝、肾中微量元素代谢紊乱可能是铅、镉毒性损伤的重要机制之一。 相似文献
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1981年,提出了红细胞免疫系统的假说,认为红细胞不仅具有呼吸功能,而且具有识别、粘附、杀伤抗原、清除免疫复合物(CIC)的功能[1],同时还得出试验结论,凡影响免疫功能的疾病,其红细胞上C3b受体的数量都出现明显的减少,其原因是病原 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