[目的]用高效液相色谱建立金银花中有效成分含量的检测方法.[方法]采用梯度洗脱方法,对金银花75％甲醇提取液中绿原酸、新绿原酸、隐绿原酸、异绿原酸A、异绿原酸B、异绿原酸C、芦丁和木犀草苷8种成分的含量进行研究.[结果]8种成分在各自范围内线性关系均良好(R2＞0.999 0);平均回收率为98.98％～102.84％(n=6);相对标准偏差为0.90％～4.11％.10批金银花样品均表现为绿原酸含量最高,含量为26.93～31.90 mg/g,且8种成分含量的RSD均符合标准.[结论]该方法简单稳定,适合金银花中有效成分的定量测定.

[目的]建立苍术高效液相色谱指纹图谱.[方法]采用艾杰尔-飞诺美Venusil MPC18色谱柱(150 mm×4.6 mm,5μm),流动相为水、甲醇和乙腈,梯度洗脱,检测波长270 nmn,流速1.0 mL/min,柱温30℃.进行相似度、聚类分析和主成分分析.[结果]建立了苍术的高效液相色谱指纹图谱,18批苍术样品的相似度在0.479～0.984之间,共标定出18个共有峰,并通过对照品指认了其中3个色谱峰.聚类分析将18批苍术样品分为6类,主成分分析后缩减为5个主成分.[结论]该方法快速可靠,稳定性和重复性好,可用于苍术的质量控制.

本试验旨在探索α-倒捻子素对奶牛乳房炎源性金黄色葡萄球菌诱发感染奶牛乳腺上皮细胞(bMECs)促炎反应的抑制作用.用微量稀释法测定α-倒捻子素对金黄色葡萄球菌的最小抑菌浓度(MIC);CCK-8法测定α-倒捻子素的细胞毒性作用;RT-PCR和ELISA法分别测定细胞的TNF-α、IL-1β和IL-6 mRNA和蛋白表达水平;Western Blot法测定NF-κB p-p65蛋白的表达量.结果 显示:α-倒捻子素对金黄色葡萄球菌的MIC为1.6 μg/mL;α-倒捻子素在0～ 3.2 μg/mL范围内对bMECs增殖没有明显的影响(P＞0.05);添加不同终浓度的α-倒捻子素(0.4、0.8μg/mL和1.6 μg/mL)不仅均能抑制金黄色葡萄球菌入侵bMECs(P ＜0.01),还能显著抑制金黄色葡萄球菌感染bMECs引起的TNF-α、IL-1β和IL-6 mRNA转录水平和蛋白水平的升高(P＜0.01);金黄色葡萄球菌感染bMECs后可显著上调NF-κB p65蛋白磷酸化水平(P＜0.01),添加0.4 μg/mL和1.6 μg/mL终浓度的α-倒捻子素可显著降低p65蛋白磷酸化水平(P＜0.01),但是添加0.8μg/mL终浓度的α-倒捻子素也能降低p65蛋白的磷酸化水平,但无统计学意义(P＞0.05).结果 表明α-倒捻子素对金黄色葡萄球菌有较强的抗菌作用,能够显著抑制金黄色葡萄球菌对bMECs的侵袭,有效缓解金黄色葡萄球菌感染bMECs引起的TNF-α、IL-1β和IL-6表达水平的上调,其抗炎的分子机理可能与NF-κB信号通路相关.

The standardized management of students is of great significance to enhance the management of students. The veterinary profession as a traditional and special agricultural specialty, the existence of it's student management specification particularity, this feature from veterinary students, the existing management specification deficiencies and innovative methods and approaches are studied, and tries to provide reference for the management of students animal medicine specialty.

动物解剖学是研究正常动物有机体的形态、结构及发生发展规律的科学.它是高等农业院校动物医学、动物科学等专业共同开设的一门重要的专业基础课,该课程名词概念繁多,内容复杂,具有很强的直观性和实践性,这对教和学提出了较高的要求.而高职兽医专业的教育有别于本科普通高等兽医教育的相对独立的层次和体系,它侧重于培养“技工型”、“操作型”人才,因此对这门课程的教学增加了难度,对实践教学环节提出了更高的要求.但在都市农业背景对畜牧兽医人才培养规格的变化以及实验动物等的价格的升高和动物福利观念的普及的条件下,给解剖学的实践教学增加了复杂性.为此北京农学院开展了教学改革,对于提高动物解剖学的教学效果取得了一定的成效.

研究了混凝剂对牛沼液的净化效果,选择最佳处理工艺,为畜禽废弃物厌氧发酵沼液的循环利用和安全排放提供科学依据.采用3种混凝剂、1种助凝剂,分别对牛沼液进行混凝试验,用矾花的形成、大小、沉降速度、浊度和CODcr值及其去除率评价其净化效果.结果表明:以氯化铁(320 mg·L-1)二次混凝的效果最好,矾花形成最快且相对最大、浊度为119.4 NTU,COD值为260 mg·L-1.将处理污水的混凝工艺技术应用在牛沼液的净化处理中,取得了良好的净化效果,有望达到国家畜禽养殖业污染物排放标准.

To explore purification approach of anaerobic-digested-slurry from cattle dung, this study translated a technology in inorganic coagulation. Under the same condition, a coagulation experiment was carried out by three kinds inorganic coagulants such as polyaluminium chloride (PAC), aluminum sulfate and ferric chloride, respectively, then measured indicators of pH value, BOD5 value, CODcr value, ammonia nitrogen value, turbidity value. Results showed that there was a varying degree of purification effect, and the removal rate of the above indicators increased as the coagulant dosage increasing, the ferric chloride with the dosage of 960mg/L was the best one in purifying effect among the three coagulants. It is feasible that coagulation technology was used to pretreatment biogas slurry from cattle dung, and most of the indicators reached Chinese national standard basically (GB 18596-2001).

Ninety hyline white hens aged 50 days were randomly allocated to 3 groups of 30 hens each.In feed,140 mg/kg CdCl2 was added into the low-dosage cadmium(Cd) group,210 mg/kg CdCl2 was added into the high-dosage cadmium group and the hens in the control group fed on the diet without Cd.Individually on day 20,40 and 60 post-treatment,livers of chickens were collected to detect expression of DNMT1 mRNA,DNMT3a mRNA and DNMT3b mRNA by RT-PCR.The fact that cadmium increased the expressions of DNMT1 mRNA and DNMT3a mRNA along with prolongation of time showed that DNA methylation might be involved in the carcinogenic action of cadmium.

To investigate the relationship between the methylation of p15 gene and the genesis of kidney tumor in the development of Marek's disease(MD),300 one-day-old chicks were randomly divided into control group and MD group.On 35,40 and 45 days-old,kidneys were collected and then pathologic changes were observed in the experimental replication MD cases and the variations of methylation of p15 gene in the genesis and development of kidney tumor of chicks with MD were detected by the methylated specific PCR.The results showed that the clinical manifestations and pathological changes of the kidney in the MD group were in accord with characteristics of MD,indicating that MD model was successfully generated.No methy-lation of p15 gene was generated in the control group,while 61.7% of methylation of p15 gene was found in the MD group,which was significantly higher(P0.01) than that in the control group in time-dependent manner.It was concluded that the methylation of p15 gene was intimately relevant to the genesis and development of MD.

镉是一种重要的环境污染物,动物镉中毒的主要原因是饲料中镉含量超标[1].进入机体中的镉将长期蓄积,对多器官和系统产生损伤.长期以来,人们对其致肝、肾、睾丸等器官及其线粒体损伤的研究较多,但对鸡垂体细胞线粒体损伤及垂体内酶活性的影响未见报道.

Cadmium is a persistent pollutant that poses a threat to most biological organisms including birds. Although toxicity of cadmium is mainly linked to cancer, the mechanism of its carcinogenic activity remains poorly understood. Since DNA methylation is linked to cancer, we have examined the effect of cadmium on DNA methylation and DNMTs mRNA expression in hen liver and kidney. Sixty 50-day-old hyline-white hens were randomly allocated into 3 equal groups; a control group fed a basal diet, a low-dose group fed the basal diet spiked with 140mg/kg CdCl(2), and a high-dose group fed the basal diet spiked with 210mg/kg CdCl(2). After 60 days, liver and kidney samples were analysed for cadmium by FAAS, DNA methylation level by HPLC and DNMTs mRNA levels by semi-quantitative RT-PCR. The DNA methylation levels and the expressions of DNMT1 and DNMT3a mRNA in liver and kidney were significantly elevated by the cadmium treatment but there was no change in the expression of DNMT3b mRNA in the two tissues. The fact that cadmium increases DNA methylation and the expressions of DNMT1 and DNMT3a mRNA in liver and kidney suggests DNA methylation may be involved in the carcinogenic action of cadmium.

The effect of cadmium chloride on cell apoptosis and the expressions of Fas and caspase-3 genes were explored in a hen model, Ninety normal Hyline white laying hens, aged 50 days, were randomly allocated to 3 groups of 30. The hens were fed 0 mg·kg-1 CdCl2 in the control group, 140 mg·kg-1 CdCl2 in the low-dosage cadmium group and 210 mg·kg-1CdCl2 in the high-dosage cadmium group. The anterior pituitary glands of the hens were removed after 20 d, 40 d and 60 d and the levels of cell apoptosis were detected by TUNEL and the expressions of Fas and caspase-3 genes were measured by RT-PCR. The results indicated that cadmium chloride can lead to apoptosis of pituicytes and overexpression of Fas and caspase-3 genes. At the same time point, cell apoptosis rates and gene expression showed variance (p0.01) in both test groups compared with control and the low-dosage group changed greatly both the expression of Fas, caspase-3 mRNA and cell apoptosis rates. The data indicated that cadmium chloride could induce apoptosis of anterior pituitary cells. The expression of Fas and caspase-3 mRNA have the same trend as apoptosis with the extension of time.

Flame atomic absorption spectrographic method was used to determine the cadmium accumulation in the ovaries and serum of sexually immatured hen. These hen were all fed complete feeds with cadmium chloride of 0, 140 and 210 mg/kg, for 20, 40 and 60 days respectirely. The result showed that cadmium accumulation increased with the doses and time of cadmium supplementation.

DNA甲基化(DNA methylation)是哺乳类动物体内极为重要的自然化学修饰方式,能调控体内基因的表达,影响细胞的增殖和分化,与动植物生长发育关系密切,是目前表遗传学研究的热点[1].环境中的哪些因素能影响DNA甲基化,目前还有待进一步研究,其中重金属与DNA甲基化有关.研究发现,重金属中毒能影响DNA总甲基化水平、甲基转移酶的活力和某些抑癌基因的表达,现就重金属中毒对DNA甲基化的影响做一综述.

镉是地壳中丰度很少的重金属元素,但由于人类的生产活动,它已成为当今环境中主要的污染物,随着水和土壤的污染,威胁着水生生物和动植物及人类的健康.大量的研究表明,镉中毒可引起多器官损伤.镉已被证实为一种环境雌激素,在很低的接触水平就可能对包括垂体在内的内分泌系统产生严重的损害[1].以往的研究表明,氧化应激是镉中毒的机制之一,并且镉可通过氧化应激诱导细胞凋亡[2],但这是否是镉诱导鸡垂体细胞凋亡的一个机制,目前还未见报道.本研究用不同浓度的CdCl,对鸡进行亚慢性体内染毒,通过抗氧化指标和凋亡的检测,探讨镉对鸡垂体氧化应激和细胞凋亡的影响以及两者的关系.

[OBJECTIVE] To study the accumulation of cadmium and the changes of morphology in chicken liver induced by sub chronic cadmium. [METHOD] 30 normal Hyline white laying hens, aged 50 days, were randomly allocated to 3 groups and each group included 10 respectively. In feed, we added 0 mg/kg CdCl2, 140 mg/kg CdCl2, 210 mg/kg CdCl2 separately into control group, low-dosage cadmium group and high-dosage cadmium group. Liver was got to determinate the contents of cadmium and observe changes of microstructure or ultrastructure at 20d?40d and 60d after cadmium exposure. [RESULTS] Accumulation of cadmium in liver showed time-effect curve and dose-effect curve. Denaturation and necrosis of cadmium-group liver cell could be seen, mitochondria and endoplasmic reticulum were enormously damaged. [CONCLUSION] Liver was one of the target organ of cadmium and the damage of liver changed deeper with time goes on and elevation of cadmium dose.

镉是一种重金属,镉在体内的生物半衰期长达10～30年,少量镉持续进入体内因长期积累而对各组织器官有不同程度的损伤,为已知的最易在体内蓄积的毒物.试验采用火焰原子吸收法对染镉鸡垂体中镉的蓄积情况进行检测,以探讨镉对内分泌器官毒性的影响,为进一步研究其毒理提供依据.