富硒麦芽对二乙基亚硝胺诱发大鼠肝癌血管生成的影响

试验选择雄性SD大鼠100只,体重100~120 g,随机分成3组。试验Ⅰ组日粮中添加富硒麦芽（SEM）使硒含量达到3.0 mg/kg;试验Ⅱ组为模型组;试验Ⅲ组为阴性对照组,不诱癌不加SEM;试验Ⅱ、Ⅲ日粮中分别添加亚硒酸钠使硒含量达到0.1 mg/kg。试验Ⅰ、Ⅱ组饮水中添加100 mg/L二乙基亚硝胺（diethylnitrosamine,DEN）诱癌,维持DEN摄入量每天约10 mg/kg体重,连续16周,然后改饮普通灭菌水至18周末。试验Ⅲ组始终以普通灭菌水自由饮用。18周末,处死大鼠。利用免疫组织化学法分析大鼠肝肿瘤微血管密度（microvessel density,MVD）和血管内皮生长因子（VEGF）的表达。结果表明,SEM组MVD和VEGF表达较模型组显著降低。因此,表明SEM对肝肿瘤血管生成有抑制作用,下调VEGF表达可能是其抑制肿瘤血管生成的主要机理之一。     

富硒麦芽对二乙基亚硝胺诱发大鼠肝癌病理学变化的影响

雄性SD大鼠180只,体重100～120g,随机分成5组。组Ⅰ为阴性对照组,不诱癌、不加富硒麦芽(SEM),组Ⅱ为模型组,组Ⅰ和组Ⅱ日粮中分别添加亚硒酸钠至硒含量达0.1mg/kg;组Ⅲ～组Ⅴ,日粮中分别添加SEM至硒含量为0.3、1.0、3.0mg/kg。组Ⅰ始终以普通灭菌水自由饮用;组Ⅱ～组Ⅴ,饮水中添加100mg/L二乙基亚硝胺(Diethylnitro-samine,DEN)诱癌,维持DEN摄入量每天约10mg/kg体重,连续16周,然后改饮普通灭菌水至18周末。18周末,处死大鼠。诱癌过程中通过肉眼和光镜动态观察各组大鼠的病理学变化。结果显示,SEM组的肝脏病理学变化轻于或显著轻于模型组。结果表明,补充一定量的SEM能延缓和阻滞大鼠肝癌的发生、发展进程。     

富硒麦芽对二乙基亚硝胺诱发大鼠肝癌肝细胞超微结构变化的影响

雄性SD大鼠180只,体重100~120g,随机分成5组。组Ⅰ,对照组,不诱癌不加富硒麦芽(SEM);组Ⅱ,模型组。组Ⅰ和组Ⅱ,日粮中分别添加亚硒酸钠至硒含量达0.1mg/kg;组Ⅲ~组Ⅴ,日粮中分别添加SEM至硒含量为0.3、1.0、3.0mg/kg。组Ⅱ~组Ⅴ,饮水中添加100mg/L二乙基亚硝胺(Diethylnitrosamine,DEN)诱癌,维持DEN摄入量每天约10mg/kg体重,连续16周,然后改饮普通灭菌水至18周末。组Ⅰ始终以普通灭菌水自由饮用。18周末,处死大鼠。诱癌过程中通过电镜动态观察各组大鼠的肝细胞超微结构变化。结果显示,SEM组的肝细胞超微结构变化轻于或显著轻于模型组。结果表明,补充一定量的SEM能延缓和阻滞大鼠肝癌的发生、发展进程。     

富硒麦芽硒对二乙基亚硝胺所致大鼠肝癌模型肝硬变前期的肝损伤及伴癌综合征的影响

将体质量100～120g的雄性SD大鼠258只随机分为7组。Ⅰ组，0．3mg／kg富硒麦芽硒组；Ⅱ组，1mg／kg富硒麦芽硒组；Ⅲ组，3mg／kg富硒麦芽硒组；Ⅳ组，3mg／kg亚硒酸钠硒组；Ⅴ组，诱癌阳性对照组；Ⅵ组，3mg／kg亚硒酸钠硒不诱癌组；Ⅶ组，阴性对照组，不加硒也不诱癌。Ⅰ～Ⅴ组，饮水中添加二乙基亚硝胺（DENA，100mg／L）以诱癌。每2周眼眶采血1次，测定血浆丙氨酸氨基转移酶（ALT）、碱性磷酸酶（ALP）、总胆红素（TBIL）、白蛋白（ALB）、葡萄糖和血清钙含量、全血GSH-Px活性等。结果发现，富硒麦芽硒比亚硒酸钠硒能更有效地抑制DENA所致大鼠肝损伤，提高大鼠全血GSH-Px活性，并以1mg／kg添加刺量效果较佳；DENA所致大鼠肝肿瘤初期即伴随着明显的低血糖症。结果表明：富硒麦芽比亚硒酸钠能更有效抑制DENA所致的初期肝损伤，保护肝脏，提高抗氧化能力。     

富硒麦芽对二乙基亚硝胺诱发大鼠肝癌发生、发展的影响

硒是人体一种必需的微量元素。大量的流行病学资料和动物实验证明,硒与多种人类癌症的发病率呈负相关,并能显著地预防和抑制动物的自发性、移植性和化学致癌剂诱发的肿瘤的发生、发展、播散和复发。     

富硒麦芽对二乙基亚硝胺诱发大鼠肝癌过程中肝癌特异性指标和肝功能的影响

硒是人体一种必需的微量元素。大量的流行病学资料和动物实验证明,硒与多种人类癌症的发病率呈负相关,并能显著地预防和抑制动物的自发性、移植性和化学致癌剂诱发的肿瘤的发生、发展、播散和复发。人群试验也表明,硒可以降低肿瘤的发生率。     

富硒麦芽对二乙基亚硝胺致肝癌大鼠低血糖症及相关体液调节因子动态变化的影响

雄性SD大鼠193只，体重100～120g，随机分成5组。组Ⅰ～组Ⅲ，日粮中添加富硒麦芽（SEM）至硒含量分别为0．3、1．0、3．0mg／kg；组Ⅳ，模型组；组Ⅴ，阴性对照组，不加SEM也不诱癌，日粮中分别添加亚硒酸钠至硒含量达0．1mg／kg。组Ⅰ～组Ⅳ，饮水中添加100mg／L二乙基亚硝胺（Diethylnitrosamine，DEN）诱癌，维持DEN摄人量每天约10mg／kg体重，连续16周，然后改饮普通灭菌水至18周末。组V始终以普通灭菌水自由饮用。每4周眼眶采血1次，测定血浆葡萄糖及其相关体液调节因子胰岛素、胰高血糖素、胰岛素样生长因子Ⅱ（IGF-Ⅱ）等的含量，统计胰岛素／葡萄糖（IGR1）、胰岛素／胰高血糖素（IGR1）、胰高血糖素／葡萄糖（GGR）值。分析血糖与各相关调节因子间的相关性。结果发现，与同期阴性对照组相比，各诱癌组大鼠血糖和血清胰岛素、胰高血糖素水平及GGR值均显著下降，血清IGF-Ⅱ水平和IGRz值则显著上升，而某些剂量的SEM能有效地抑制血糖、胰高血糖素水平的下降和血清IGF-Ⅱ水平、IGR2值的上升。血糖与上述各调节因子间分别存在显著相关性。结果表明SEM能抑制肝癌大鼠低血糖症的发生，该作用可能是通过对诸多相关调节因子的共同调节而实现的。     

富硒麦芽对二乙基亚硝胺诱发大鼠肝癌过程中脂质过氧化的影响

大量的研究已证实，硒具有抗肿瘤作用。但迄今为止，硒的确切抗癌机理尚未完全阐明。自由基脂质过氧化作用与肿瘤的关系极为密切。硒作为谷胱甘肽过氧化物酶（GSH-PX）的重要组成部分，具有清除自由基对抗氧化损伤的作用。     

富硒麦芽对实验性肝癌大鼠NO、NOS和脂质过氧化的影响

50只清洁级sD大鼠随机分为4组：对照组（5只）、模型组（15只）、富硒麦芽组（15只）和亚硒酸钠组（15只）。对照组和模型组饲喂大鼠基础饲料，饲料含硒量为0．1mg／kg；富硒麦芽组和亚硒酸钠组分别在基础饲料中补充富硒麦芽和亚硒酸钠，饲料含硒量为3．0mg／kg。除对照组外，其余3组采用0．01％二乙基亚硝胺（DEN）诱发大鼠肝癌16周，停止诱癌后继续饲养2周再处死全部大鼠，观察富硒麦芽对丙氨酸氨基转移酶（ALT）、碱性磷酸酶（ALP）、白蛋白（ALB）、总胆红素（TBIL）、一氧化氮（NO）、一氧化氮合成酶（NOS）、丙二醛（MDA）和谷胱甘肽过氧化物酶（GSH—Px）的影响。结果显示，富硒麦芽组大鼠血浆ALT、ALP、TBII—NO、MDA和肝组织NO、NOs、MDA显著低于模型组，全血和肝组织GSH—Px活性显著高于模型组；与亚硒酸钠组相比，富硒麦芽组大鼠血浆和肝组织的NO含量和NOS活性显著降低。试验表明富硒麦芽具有减轻肝脏损伤、延缓大鼠肝癌形成的能力，其作用机制之一可能为富硒麦芽能抑制NO的产生，清除体内大量过剩的氧自由基。减轻NO等自由基所致的脂质过氧化损伤。     

富硒酵母对长期缺硒和正常大鼠体内D-丝氨酸和L-丝氨酸水平的影响

本试验在建立缺硒大鼠模型的基础上,研究饲粮补充富硒酵母对长期缺硒和正常大鼠体内D-丝氨酸与L-丝氨酸水平的影响.将3周龄Sprague-Dawley大鼠随机分为缺硒组和正常组,分别饲喂低硒饲粮(含硒0.02 mg/kg)和正常饲粮(含硒0.18 mg/kg),饲喂期为420 d.第421天,将缺硒组大鼠分为4组:缺硒空...     

Effect of selenium-enriched malt on hypoglycemia and regulatory hormones in diethylnitrosamine-induced hepatocarcinoma SD rats

One hundred and ninety-three Sprague-Dawley (SD) rats (average body weight being 100–120 g) were randomly divided into 5 groups (I–V). Animals in group I and group II served as the negative control and positive control, respectively, and both received 0.1 mg/kg selenium (Se) from sodium selenite. Animals in groups III–V were fed with Se from Se-enriched malt (SEM) supplemented diets (0.3, 1 and 3 mg/kg, respectively). Simultaneously, hepatocarcinoma were induced in groups II–V by diethylnitrosamine (DEN) solution (100 mg/L) at the dosage of 10 mg/kg body weight every day as drinking water for 16 weeks, then sterilized water for a further two weeks. Rats of group I drank sterilized water during the whole experimental time. At 4th, 8th, 12th, 16th week, five rats in each group were then sacrificed by cervical decapitation. At the termination of the study, at 18th week, the surplus rats were sacrificed by cervical decapitation. Feed was withheld from the rats for 12 h before sampling. The values of plasma glucose at different sampling times were measured. The values of the hormones in plasma related to plasma glucose metabolism, including insulin, glucagon, insulin-like growth factors-II (IGF-II), and the ratios of insulin/glucose (IGR₁), insulin/glucagon (IGR₂) and glucagon/glucose (GGR) were determined. At the same time, the correlation of plasma glucose concentrations related to hormones was statistically analyzed. The results indicated that the values of plasma glucose, insulin, glucagon and GGR in the groups treated with DEN were decreased significantly as compared with that of the negative control group, however, the values of IGF-II and IGR₂ were increased significantly. SEM showed a significant effect in suppressing the decreased of plasma glucose and glucagons, and delaying the increased of IGF-II and IGR₂ in the DEN-induced hepatocarcinoma rats. The plasma glucose concentrations revealed a significant relation to the hormones. In conclusion, SEM could reduce the development of hypoglycemia in the DEN-induced hepatocarcinoma rats by regulating the relative levels and balances or proportions of hormones.     

富硒酵母对大鼠生产性能、脏器指数以及血常规指标的影响

将40只SD大鼠随机均分为4组(雌雄各半):对照组、低剂量组、中剂量组和高剂量组.对照组饲喂基础日粮,低剂量组、中剂量组和高剂最组分别饲喂含0.036%、0.144%和0.288%富硒酵母的日粮,持续28 d.在试验过程中,记录大鼠的增重和采食量,计算食物利用率.试验结束时,记录大鼠心脏、脾脏、肝脏、肾脏、睾丸、卵巢重量并计算脏器指数,试验结束时采取血液样本进行血常规指标测定.结果表明,高、中、低剂量组大鼠的食物利用率、心脏、脾脏、睾丸、卵巢指数以及血液常规指标与对照组相比均无显著差异(P>0.05);高剂鼍组大鼠的增重和采食量显著低于对照组(P<0.05),高剂量组大鼠的肾脏指数和肝脏指数显著高于对照组(P<0.05).低、中剂量富硒酵母日粮对大鼠的增重、采食量、肾脏、肝脏指数无明显影响;高剂量富硒酵母日粮对大鼠的增重、采食量、肾脏、肝脏指数有明显影响.     

富硒酵母对断奶羔羊生长性能及抗病力的影响

为研究富硒酵母制剂对断奶羔羊生长性能及抗病能力的影响,分析其临床应用效果,试验选取日龄相近断奶羔羊40只,随机分为高剂量组(2.0mg/kg)、中剂量组(1.0mg/kg)、低剂量组(0.5mg/kg)和对照组4组,连续用药30d,测定各组羔羊平均日增重、血液生理生化指标,并统计各组羔羊发病情况。结果表明,试验组羔羊平均日增均对照组,其中,高剂量组断奶羔羊平均日增重与对照组差异极显著(P<0.01);血液生理指标测定结果表明,高剂量组、中剂量组的白细胞数目(WBC)与对照组差异极显著(P<0.01),而3个试验组的红细胞数目(RBC)均与对照组差异显著(P<0.05);血液生化指标测定结果表明,高剂量组的谷丙转氨酶与对照组差异极显著(P<0.01),白蛋白(ALB)、葡萄糖(GLU)与对照组差异显著(P<0.05);高剂量组和中剂量组的总胆固醇(CHOL)均与对照组差异显著(P<0.05);对各组羔羊腹泻率统计分析,发现试验组腹泻率均低于对照组,其中,高剂量组的腹泻率最低,仅为3.3%。综上所述,中剂量的富硒酵母对断奶羔羊具有良好的促生长和抗腹泻作用。     

细胞因子在犬新孢子虫感染中的作用

犬新孢子虫是一种专一性细胞内寄生虫，它的感染导致了宿主Th细胞的分化。一方面，刺激宿主产生Th1型细胞因子反应，这些细胞因子包括IL-12、IFN-7和INF-α。Th1型细胞因子反应同时还激活了产生氧自由基（FOR）、一氧化氮（NO）及其代谢物，这些细胞因子对犬新孢子虫均具有致命的杀伤力。另一方面，引发宿主产生IL-4、IL-5和IL-10等Th2型细胞因子，Th2型细胞因子主要在宿主妊娠过程中发挥作用。     

Effect of danazol on NK cells and cytokines in the mouse uterus

Danazol, which has been used as a medicine for endometriosis, has a valid effect in pretreatment of patients receiving in vitro fertilization and embryo transfer, although its reproductive mechanism remains unclear. BALB/c mice were subcutaneously injected with danazol for 2 weeks. Blood and uteri were collected and cytokines were assayed. Following danazol treatment, an increase in pregnancy ratio was evident that was accompanied by up-regulation in serum macrophage-colony stimulating factor (M-CSF). RT-PCR analysis revealed that expression of M-CSF and Ly49, a phenotypic marker of natural killer (NK) cells, was up-regulated in the uteri of the danazol-treated mice. In immunohistochemical analysis, M-CSF and Ly49, together with alpha5 integrin, were clearly detected in the endometrium of the danazol-treated mice with very similar pattern of localization. These results suggest that danazol has an effect to promote pregnancy that induces recruitment of NK cells and a concomitant increase in the expression of M-CSF and alpha5 integrin in the uterus.     

细胞因子在猪呼吸道疾病中的作用

细胞因子如干扰素 α (IFN α) ,肿瘤坏死因子 α (TNF α) ,白细胞介素 1、 6和 8(IL 1、 6、 8) ,在多数感染的早期都会产生。它能调节细胞生长分化 ,调节免疫功能。这些细胞因子的活性已经在体外和小鼠试验中广泛研究 ,但有关细胞因子在肉用动物感染中的体内试验研究却很少。特别是病毒感染呼吸道后 ,细胞因子在体内出现的时间、机体临床表现以及抗病毒抗细菌感染的机理值得研究探讨。本文综述猪呼吸道感染中细胞因子的作用 ,并探讨其对呼吸道病毒性感染的相关性     

酵母对硒元素的富集研究和改良策略

<正>硒在自然界中以无机硒和有机硒两种形式存在。与无机硒相比,有机硒具有吸收率高、生物活性强、毒性低、环境污染小等特点。有机硒可由人工合成,也可通过生物转化和生物富集等不同方式生产。目前较为广泛采用的是酵母菌富集法,即利用酵母菌对无机硒进行富集和生物有机化,生产富硒酵母。     

胃肠宁对脾虚大鼠胃肠激素和炎性细胞因子的影响

目的:探讨胃肠宁对脾虚证动物胃肠激素和炎性细胞因子的影响。方法:采用苦寒泻下法复制大鼠脾虚证模型,研究胃肠宁对脾虚大鼠血清中IL-10、IL-1β及回肠始段SP、VIP含量的影响。结果:脾虚证大鼠血清中IL-10水平显著降低(P<0.05),IL-1β水平显著升高(P<0.05),胃肠宁能在一定程度上恢复IL-10和IL-1β含量,但与自然康复组相比差异不显著(P>0.05);脾虚证大鼠回肠始段SP含量显著升高(P<0.05),VIP含量显著降低(P<0.05),胃肠宁能显著恢复脾虚大鼠回肠始段SP和VIP含量(P>0.05)。结论:胃肠宁对脾虚证具有较好的治疗作用,其作用机制主要是能显著改善脾虚大鼠回肠始段SP和VIP水平。     

不同细胞因子对水牛原始生殖细胞传代培养的影响

为探讨不同细胞因子对水牛原始生殖细胞（PGCs）传代培养的影响，将PGCs分别采用A、B、C、D、E、F和G共7种培养基进行培养，即A组：基础液＋10ng／mL白血病抑制因子（LIF）＋10ng／mL碱性成纤维细胞生长因子（bFGF）；B组：基础液＋20ng／mL LIF＋20ng／mL bFGF；C组：基础液＋20ng／mL LIF＋10ng／mL bFGF；D组：基础液＋20ng／mL LIF；E组：基础液＋20ng／mL LIF＋20ng／mL bFGF＋20ng／mL干细胞因子（SCF）；F组：基础液＋20ng／mL LIF＋40ng／mL bFGF＋40ng／mL SCF；G组（对照组）：基础液。将机械法分离的PGCs小集落接种到水牛胎儿成纤维细胞（BEF）饲养层上进行传代培养。结果，原代时，A、B、C、D、E和F组的克隆数目都显著高于对照组（P％0．05），其中E和F组的克隆数目显著高于A组（P〈0．05），而与B、C、D组差异均不显著（P〉0．05）；1～8代时，B、C、D、E、F组的克隆数目显著高于A组（P〈0．05）；对照组传代数仅为2代，A组为5代，而B、C、D、E和F组均为8代以上。结果表明，在传代过程中，LIF起主要作用，20ng／mL的LIF浓度可以满足水牛PGCs传代培养的需要。     

Effect of dietary supplementation with selenium-enriched yeast or sodium selenite on selenium tissue distribution and meat quality in beef cattle

The objective was to determine the concentration of total Se and the proportion of total Se comprised as selenomethionine (SeMet) and selenocysteine (SeCys) in postmortem tissues of beef cattle offered diets containing graded additions of selenized enriched yeast (SY; Saccharomyces cerevisiae CNCM I-3060) or sodium selenite (SS). Oxidative stability and tissue glutathione peroxidase (GSH-Px) activity of edible muscle tissue were assessed 10 d postmortem. Thirty-two beef cattle were offered, for a period of 112 d, a total mixed ration that had been supplemented with SY (0, 0.15, or 0.35 mg of Se/kg of DM) or SS (0.15 mg of Se/kg of DM). At enrollment (0 d) and at 28, 56, 84, and 112 d following enrollment, blood samples were taken for Se and Se species determination, as well as whole blood GSH-Px activity. At the end of the study beef cattle were killed and samples of heart, liver, kidney, and skeletal muscle (LM and psoas major) were retained for Se and Se species determination. Tissue GSH-Px activity and thiobarbituric acid reactive substances were determined in skeletal muscle tissue (LM only). The incorporation into the diet of ascending concentrations of Se as SY increased whole blood total Se and the proportion of total Se comprised as SeMet, as well as GSH-Px activity. There was also a dose-dependent response to the graded addition of SY on total Se and proportion of total Se as SeMet in all tissues and GSH-Px activity in skeletal muscle tissue. Furthermore, total Se concentration of whole blood and tissues was greater in those animals offered SY when compared with those receiving a comparable dose of SS, indicating an improvement in Se availability and tissue Se retention. Likewise, GSH-Px activity in whole blood and LM was greater in those animals offered SY when compared with those receiving a comparable dose of SS. However, these increases in tissue total Se and GSH-Px activity appeared to have little or no effect in meat oxidative stability.