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1.
本文研究了敌草快和肾上腺皮质激素对胎鼠动脉管的收缩作用。取妊娠19、20、21 d的大鼠,各随机分成2组。试验组皮下注射7 mg/kg敌草快,观察胎鼠动脉管收缩情况;取妊娠19 d大鼠,随机分成4组,试验1组未切除肾上腺,2、3组切除肾上腺。1、3组皮下注射7 mg/kg敌草快,第2组和对照组注射生理盐水,观察胎鼠动脉管收缩情况,并且测定母鼠血浆中肾上腺皮质激素的浓度;取妊娠19、20、21 d大鼠,各随机分成2组,试验组皮下注射40 mg/kg肾上腺皮质激素,观察胎鼠动脉管收缩情况,另用80 mg/kg肾上腺皮质激素,重复上述操作。结果表明:敌草快和肾上腺皮质激素对妊娠末期胎鼠动脉管具有收缩作用,且引起收缩的临界期均在胎龄19￣20 d。 相似文献
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除草剂敌草快(Diquat)所致的大鼠胎儿动脉管收缩与血管紧张素及其受体的关系 总被引：1，自引：0，他引：1
为研究除草剂敌草快（Diquat）对胎儿动脉管的毒性作用机理，进行了以下3个试验：（1）取妊娠21d大鼠20只，随机分成5组，每组4只，于不同时间皮下注射敌草快7mg／kg，对照组注射等量生理盐水。取出胎儿，冷冻后，观察动脉管收缩情况。（2）取妊娠21d大鼠16只，随机分成4组，每组4只。试验1组母体皮下注射敌草快7mg／kg，2、3组通过子宫壁给胎儿分别注射D．05mL生理盐水和0．05mL（0．05mg）非选择性血管紧张素（ET）受体ETA／ETB拮抗药TAK-044后，再母体皮下注射敌草快7mg／kg，取出胎儿，观察动脉管收缩情况。（3）取妊娠21d大鼠16只，随机分成4组，每组4只。试验1组母体皮下注射敌草快7mg／kg，2、3组通过子宫壁给胎儿分别注射0．05mL生理盐水和0．05mL（0．02mg）选择性ETA受体拮抗药BQ-123后，再母体皮下注射敌草快7mg／kg，取出胎儿，观察动脉管收缩情况。结果表明，敌草快对妊娠末期胎儿动脉管有毒性作用，胎儿注射TAK-044和BQ-123都不引起动脉管收缩。由此可见，敌草快所致胎儿动脉管收缩与ET有关，且有ETA受体作为媒介参与。 相似文献
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本文研究了百草枯对胎儿动脉管的毒性作用机理。取妊娠21d大鼠随机分成5组,在不同时间皮下注射25mg/kg百草枯,观察胎儿动脉管收缩情况;取妊娠21d大鼠随机分成4组,试验第1组母体皮下注射25mg/kg百草枯,第2组和第3组胎儿分别注射生理盐水和TAK-044后,母体皮下注射25mg/kg百草枯,观察胎儿动脉管收缩情况;用BQ-123代替TAK-044重复上述操作。结果表明:百草枯对妊娠末期胎儿动脉管具有毒性作用;由百草枯引起的胎儿动脉管收缩与ET有关,且以ETA受体作为媒介参与动脉管收缩。 相似文献
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胆酸负荷对妊娠大鼠母体及其胎儿IGF-2和营养代谢物水平的影响 总被引：2，自引：0，他引：2
30只成年妊娠SD大鼠随机分为A，B，C3组，在妊娠13－20d给A组和B组大鼠每天分别腹腔注射2.9mg/kg和5.5mg/kg胆酸，C组同步注射等量生理盐水。妊娠21d时宰杀母鼠，剖腹取胎，测定胎儿体重，胚胎成活率。并采集母体和胎儿血样，测定IGF－2、胰岛素和代谢物水平。结果表明，低剂量胆酸注射导致胎儿成活率降低7．02％，胎儿血浆IGF－2升高及乳酸和总蛋白水平降低，母体血浆IGF－2和胰岛素水平降低。较大剂量胆酸注射使胎儿成活率和体重分别下降38．27％和7．33％，血浆IGF－2、胰岛素和总蛋白水平下降。结果提示长期胆酸负荷对胎儿生长发育产生严重影响，胎儿死亡率增加及生长迟缓与IGF－2、胰岛素水平降低有关。 相似文献
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为了探讨不同浓度敌草快(Diquat)诱导的氧化应激对肉鸡生产性能、肝脏功能、免疫功能和抗氧化性能的影响,同时确定敌草快诱导氧化应激的最佳剂量和作用时间。本试验将64只16日龄健康AA肉鸡随机分为4个组：对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组,3个试验组分别腹腔注射10、15和20 mg/(kg·bw)敌草快溶液,对照组注射等剂量的无菌生理盐水,试验期21 d。结果显示,3个试验组肉鸡在试验期内均处于氧化应激状态,其中试验Ⅲ组肉鸡有死亡现象,试验Ⅱ组肉鸡采食量和体重下降,肝脏肿大,肝脏功能受损;试验第7天,与对照组相比,试验Ⅱ组肉鸡血清谷丙转氨酶(ALT)活性显著升高(P<0.05),肠黏膜分泌型免疫球蛋白A(sIgA)和血清免疫球蛋白G(IgG)含量显著降低(P<0.05),肝脏组织超氧化物歧化酶(SOD)活性显著降低(P<0.05),血清总抗氧化能力(T-AOC)含量和SOD活性均显著降低(P<0.05),丙二醛(MDA)含量显著升高(P<0.05);试验第21天,各项指标显示氧化损伤有所恢复。结果表明,可选取15 mg/(kg·bw)敌草快作为诱导肉鸡... 相似文献
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本试验以酿酒酵母和枯草芽孢杆菌作为混合菌种发酵小麦麸皮,通过Amberlite XAD-2柱分离纯化制备麦麸阿魏酰低聚糖(feruloyl oligosaccharides,FOs),探讨麦麸FOs对敌草快(diquat)诱导的大鼠氧化应激是否有缓解作用。试验选用体重相近的断奶雄性大鼠48只,随机分为未攻毒组、攻毒组、攻毒+100 mg/kg BW麦麸FOs组、攻毒+200 mg/kg BW麦麸FOs组、攻毒+300 mg/kg BW麦麸FOs组和攻毒+100 mg/kg BW维生素C组,每组8个重复,每个重复1只鼠,各组大鼠均饲喂相同的商业饲料。麦麸FOs和维生素C配制成水溶液,采用灌胃的方式给予,未攻毒组、攻毒组用生理盐水替代,灌胃体积0.2 mL,连续灌胃15 d。灌胃结束当天,未攻毒组大鼠注射0.3 mL生理盐水,其他5组按0.1 mmol/kg BW的剂量腹腔注射0.3 mL敌草快。敌草快攻毒12 h后取样,分析各组大鼠血浆以及肝脏、肾脏和回肠中总抗氧化能力(T-AOC),过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性以及谷胱甘肽(GSH)和8-羟基脱氧鸟苷(8-OHd G)的含量。结果显示:1)通过混菌发酵小麦麸皮制备麦麸FOs,利用Amberlite XAD-2柱进行分离纯化,获得的麦麸FOs浓度为0.059 mmol/g。2)腹腔注射敌草快显著降低大鼠血浆中SOD活性和GSH含量(P0.05),显著降低大鼠肝脏中T-AOC,CAT、GSH-Px活性及GSH含量(P0.05),显著降低大鼠肾脏中T-AOC及CAT、SOD活性(P0.05),显著降低大鼠回肠中T-AOC,CAT、GSH-Px活性及GSH含量(P0.05),并显著提高大鼠血浆和各组织中8-OHd G含量(P0.05)。3)在敌草快引起的氧化应激状态下,灌胃一定剂量的麦麸FOs可以显著提高大鼠血浆中SOD(400 mg/kg BW)、GSH-Px活性(100和200 mg/kg BW)以及GSH含量(100和200 mg/kg BW)(P0.05),显著提高大鼠肝脏中T-AOC(100、200和400 mg/kg BW),CAT(200和400 mg/kg BW)、SOD(100、200和400 mg/kg BW)和GSH-Px活性(100、200和400 mg/kg BW)以及GSH含量(100、200和400 mg/kg BW)(P0.05),显著提高大鼠肾脏中T-AOC(400 mg/kg BW),CAT(200 mg/kg BW)和GSH-Px活性(200和400 mg/kg BW)以及GSH含量(400 mg/kg BW)(P0.05),显著提高大鼠回肠中T-AOC(200 mg/kg BW),SOD(400 mg/kg BW)和GSH-Px活性(100、200和400 mg/kg BW)以及GSH含量(100、200和400 mg/kg BW)(P0.05),显著降低血浆和各组织中8-OHd G含量(血浆、肾脏、回肠:100、200和400 mg/kg BW;肝脏:100 mg/kg BW)(P0.05);且灌胃200、400 mg/kg BW麦麸FOs后,大鼠血浆和组织中部分抗氧化相关指标可恢复到正常生理状态水平。综上所述,本试验制备的麦麸FOs可以通过有效提高大鼠血浆和组织中抗氧酶活性和GSH含量,降低DNA氧化应激代谢产物8-OHd G的含量,有效缓解由敌草快诱导产生的氧化应激。 相似文献
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《中国兽医学报》2019,(2):337-348
将60只昆明孕鼠随机分为3组,每组20只。A组为空白对照组,孕鼠妊娠1～14d灌胃玉米油。B组为双酚A(BPA)组,孕鼠妊娠1～7d灌胃玉米油,8～14d灌胃BPA(500mg/kg)。C组为菟丝子黄酮+BPA组,孕鼠妊娠1～7d灌胃1mg/kg菟丝子黄酮,8～14d灌胃BPA(500mg/kg)。母鼠产后21d剖杀,取子宫卵巢检测。组织学观察发现BPA导致子宫或卵巢组织结构损伤,预先给予菟丝子黄酮有一定缓解作用。免疫组化和免疫荧光方法检测均显示,BPA使母鼠AMH、StAR、Bax的表达水平显著升高,CYP11a1、Kitlg、Bcl-2的表达水平显著降低。菟丝子黄酮显著缓解BPA引起上述因子的变化和伤害,起到一定的保护作用。 相似文献
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《饲料工业》2019,(17):47-51
研究旨在探讨不同日粮能量水平对青海省海南地区湖羊母羊繁殖性能和初生羔羊体况的影响。选取1岁左右健康初产纯繁妊娠80 d湖羊180只,随机分成A、B和C3组,每组60只,在粗饲料[燕麦青干草0.5 kg/(只·d)、燕麦青贮0.69 kg/(只·d)]相同的情况下(干物质),精料饲喂量分别为A组0.4 kg/(只·d)、B组0.5 kg/(只·d)和C组0.6 kg/(只·d),饲喂时间为60 d。结果表明,A组母羊流产率和死胎率高于B、C两组,C组初生单羔羊的体高和体长显著高于B组(P<0.05),胸围和管围各组之间差异不显著(P>0.05),C组初生双羔羊的体长显著高于B组(P<0.05),A组与B组和C组之间差异不显著(P>0.05),管围C组显著高于A组(P<0.05),B组多羔羊初生体重显著高于A组(P<0.05),C组单羔羊平均增重显著高于A组(P<0.05)。综上所述,妊娠后期母羊精料饲喂量较高[0.6 kg/(只·d)]时,湖羊繁殖性能较好,所产羔羊的体尺、体重较高,有利于胎儿的后期生长发育。 相似文献
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旨在探讨牛磺鹅去氧胆酸(taurochenodeoxycholic acid, TCDCA)对佐剂性关节炎(AA)大鼠下丘脑-垂体-肾上腺轴(HPA)轴的影响。试验采用完全弗氏佐剂(CFA)法制备了AA大鼠,并将其分为5组,即模型组、TCDCA低剂量(0.1 g/kg)预防组和治疗组、TCDCA高剂量(0.2 g/kg)预防组和治疗组,并以正常的Wistar大鼠作为对照组,每组8只。给药方案：预防组于致炎前3 d,按照相应的药物剂量进行灌胃给药,1次/d,连续31 d。治疗组于致炎后第14天,按照相应的药物剂量进行灌胃给药,1次/d,连续14 d。通过外观观察对AA大鼠模型进行评价,并采用ELISA法检测大鼠血清中促肾上腺皮质激素释放激素(CRH)、促肾上腺皮质激素(ACTH)和皮质醇(CORT)的含量。结果显示：与正常组大鼠相比较,造模后14 d左右,模型组大鼠对侧足跖肿胀,造模后18～21 d,模型组大鼠尾部出现明显结节,提示AA大鼠模型制备成功。与正常对照组相比,模型组大鼠血清中ACTH、CORT含量显著升高(P<0.05),TCDCA低剂量治疗组可显著提高AA大鼠血清中C... 相似文献
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《畜牧与兽医》2016,(7):32-35
旨在研究妊娠后期营养限饲蒙古绵羊对其胎儿肝脏急性期蛋白合成的影响。选择健康的蒙古绵羊(经同期发情受孕)24只,在妊娠90d时选择6只母羊进行屠宰,其余18只随机均分为3个营养水平组:(0.175 MJ/kg BW~(0.75)·d,RG1组)、(0.33 MJ/kg BW~(0.75)·d,RG2组)和自由采食组(0.67 MJ/kg BW~(0.75)·d,CG组),妊娠140d时,对每组6只母羊进行屠宰。结果:RG1组胎儿肝脏重(P0.01)、肝脏中IL-1β、IL-2、INF-γ干扰素、结合珠蛋白和铜蓝蛋白显著低于CG组(P0.05),C反应蛋白显著高于CG组(P0.05),IL-4、肿瘤坏死因子(TNF)和淀粉样蛋白A差异不显著;RG2组胎儿肝脏重、肝脏中IL-1β、IL-2和TNF显著低于CG组(P0.05),而C反应蛋白极显著高于CG组(P0.01)。结果提示,妊娠后期营养限饲蒙古绵羊严重限制了其胎儿肝脏生长发育,且结构和功能也不同程度受到影响,RG1组严重影响了胎儿肝脏急性期蛋白合成,且机体适应性调控系统发生紊乱。 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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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
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献
20.
Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献