边缘无浆体膜表面蛋白1a(MSP1a)的克隆与原核表达

为了给牛边缘无浆体的诊断和基因工程疫苗的研制提供理论依据,试验以牛边缘无浆体基因组DNA为模板,采用PCR技术对其膜表面蛋白1a(MSP1a)基因进行扩增,将扩增产物转入克隆载体和表达载体中进行克隆和表达,用重组表达质粒转化大肠杆菌BL21(DE3),利用免疫印迹分析鉴定MSP1a基因表达产物的免疫活性。结果表明:MSP1a基因PCR扩增产物与GenBank上的PR1株MSP1a基因的序列同源性达98.3%,编码氨基酸的同源性为98.7%;将该基因亚克隆入原核表达载体pET-28a中,构建了重组原核表达载体;将其转化到DH5α大肠杆菌中,用IPTG进行诱导表达,实现了融合表达,表达产物的分子质量为49 ku;经SDS-PAGE电泳和免疫印迹检测,MSP1a基因在表达载体中得到高效表达,且表达产物具有免疫活性。     

内蒙古绒山羊褪黑激素受体1a基因外显子1 克隆及序列分析

参考GenBank上已发表的绵羊(登录号:15U14109)、人(登录号:U14108)、牛(登录号:U73327)、鼠(登录号:U52222)等物种褪黑激素受体(melatonin receptor 1a,MTNR1a)基因 cDNA序列设计引物,以内蒙古绒山羊基因组DNA为模板进行PCR扩增,得到257 bp的基因片段,将扩增产物进行克隆测序后与GenBank数据库进行序列同源性比较。结果表明,绒山羊MNTR1a基因外显子1序列与已发表的绵羊和牛该基因序列同源性分别为99%和96%,说明所得到的序列为绒山羊MNTR1a基因的外显子1序列。利用DNAStar软件分析,得到该基因序列的257个核苷酸。该序列包括5''UTR 23个核苷酸、翻译起始密码子ATG和N端78个氨基酸编码序列。     

EⅢ—1a型电动气雾枪

应用气雾法接种疫苗,具有方法简便、免疫效果好、节约疫苗用量、减轻劳动强度和不干扰畜禽正常生活的优点。过去气雾时使用的气雾枪都要以一定压力的气流为动力,体大,量重,使用时较为不便。1980年上海市嘉定县黄渡五金厂研制成功了轻便灵活的EⅢ—la型电动气雾枪,经上海市农科院畜牧兽医研究所鸡新城疫免疫程序研究课题试用,证明效果良好。     

GHSR-1a在奶山羊胃肠道的分布与表达

试验采用免疫组织化学、Real-time PCR和Western blotting方法测定ghrelin的功能性受体GHSR-1a(Growth hormone secretagogue receptor-1a,GHSR-1a)在奶山羊胃肠道的分布和表达。免疫组织化学结果显示,GHSR-1a免疫阳性细胞广泛分布于奶山羊胃肠道。在皱胃主要定位于黏膜层和肌层;瘤胃、网胃和瓣胃黏膜层及肌层中也可见GHSR-1a免疫阳性细胞;在小肠主要位于十二指肠、空肠和回肠的黏膜层、黏膜下层和肌层;在结肠、盲肠和直肠GHSR-1a免疫阳性细胞也有广泛分布;GHSR-1a主要表达于内在神经丛神经细胞、胃底腺上皮细胞、肠腺上皮细胞、复层鳞状上皮细胞、平滑肌细胞中。real-time PCR和Western blotting结果显示,皱胃、十二指肠、空肠、回肠、盲肠、结肠和直肠GHSR-1a的表达水平相对较高,显著高于瘤胃、网胃和瓣胃的表达(P<0.05)。结果表明,ghrelin可能通过GHSR-1a对奶山羊胃肠功能具有重要的调节作用。     

MTNR1a基因在内蒙古绒山羊卵巢中的表达

从内蒙古绒山羊卵巢中提取总RNA,根据已发表的相近物种MTNR1 DNA序列设计引物,利用RT-PCR技术对内蒙古绒山羊褪黑素受体基因MTNR1a进行PCR扩增,结果在内蒙古绒山羊卵巢中检测到了MTNR1基因的表达.     

猪细环病毒1a型ORF1基因的克隆与序列分析

为明确猪细环病毒(porcine Torque teno sus virus,PTTSuV)1a型福建株ORF1基因的特征,本研究采用分段扩增的办法从PTTSuV 1a型感染阳性粪便中扩增PTTSuV 1a型福建株ORF1基因,对PCR扩增产物胶回收克隆测序后利用SeqMan软件拼接出完整的PTTSuV 1a型福建株ORF1基因,通过分子生物学软件对其编码蛋白进行生物信息学分析。结果表明,PTTSuV 1a型福建株ORF1基因全长为1 947 bp,编码648个氨基酸,其理论等电点为10.06。核苷酸同源性比对结果表明,本试验PTTSuV 1a型福建株ORF1基因和PTTSuV 1a型TTV1 Bj2-1株(GenBank登录号:HM633243)同源性最高,达99.7%。利用Mega 6.06绘制其遗传进化树,可见PTTSuV 1a型ORF1基因在遗传进化上呈两个大的遗传进化分支(分支Ⅰ和分支Ⅱ),分支Ⅰ又可分为两个小的分支(Ⅰa和Ⅰb),本研究为丰富福建源PTTSuV 1a型分子流行病学数据库奠定基础。     

牦牛和犏牛睾丸CPT1a和ETHE1基因mRNA水平比较研究

试验旨在探索牦牛杂交雄性不育后代（犏牛）睾丸脂肪酸氧化特点及其与雄性不育的关联性,阐明犏牛雄性不育的分子机制。以GAPDH和18S rRNA基因为双内参,建立了牦牛和犏牛肝脏型棕榈酰肉碱转移酶1a（CPT1a）和硫双加氧酶1（ETHE1）基因mRNA水平的实时荧光定量PCR检测方法,结果发现,该实时荧光定量PCR方法扩增特异性好,扩增效率为98.5%~107.8%,标准曲线线性关系好。采集成年牦牛（n=9）和雄性不育犏牛（n=7）睾丸和附睾,通过常规组织切片和HE染色检测,证实犏牛睾丸和附睾中无精子,而牦牛睾丸和附睾中有精子。试验进一步从牦牛和犏牛睾丸中提取总RNA,测定睾丸中CPT1a和ETHE1基因的mRNA水平,结果显示,犏牛睾丸中CPT1a和ETHE1基因mRNA水平分别显著和极显著高于牦牛（P<0.05;P<0.01）。CPT1a基因mRNA水平的提高表明犏牛睾丸中脂肪酸β-氧化能力的加强;而ETHE1基因mRNA水平的增加可促进线粒体呼吸链的电子传递和脂肪酸氧化,或影响其他能量代谢通路,这两种基因mRNA水平的提高均有助于睾丸脂肪酸的β-氧化供能。本研究结果表明,与牦牛睾丸相比,雄性不育犏牛睾丸的脂肪酸氧化供能水平加强,可能对脂肪酸燃料分子有更多的依赖性。     

GHSR—1a在奶山羊胃肠道的分布与表达

试验采用免疫组织化学、Real—timePCR和Western blotting方法测定ghrelin的功能性受体GHSR-1a（Growth hormone seeretagogue receptor-1a,GHSR-1a）在奶山羊胃肠道的分布和表达。免疫组织化学结果显示,GHSR—1a免疫阳性细胞广泛分布于奶山羊胃肠道。在皱胃主要定位于黏膜层和肌层;瘤胃、网胃和瓣胃黏膜层及肌层中也可见GHSR-1a免疫阳性细胞;在小肠主要位于十二指肠、空肠和回肠的黏膜层、黏膜下层和肌层;在结肠、盲肠和直肠GHSR—1a免疫阳性细胞也有广泛分布;GHSR—1a主要表达于内在神经丛神经细胞、胃底腺上皮细胞、肠腺上皮细胞、复层鳞状上皮细胞、平滑肌细胞中。real—timePCR和Westernblotting结果显示,皱胃、十二指肠、空肠、回肠、盲肠、结肠和直肠GHSR—1a的表达水平相对较高,显著高于瘤胃、网胃和瓣胃的表达（P〈0．05）。结果表明,ghrelin可能通过GHsR-1a对奶山羊胃肠功能具有重要的调节作用。     

褪黑激素受体1a基因在内蒙古绒山羊垂体中的表达

本试验从内蒙古绒山羊脑垂体中提取总RNA,根据已发表的相近物种褪黑激素受体1a(melatonin receptor 1 a,MTNR1a)基因序列设计引物,利用实时荧光定量逆转录多聚酶链反应(real-time quantitative,RT-PCR)技术、组织原位杂交技术检测MTNR1a基因在内蒙古绒山羊垂体中的表达。结果显示,通过RT-PCR方法检测到MTNR1a基因在内蒙古绒山羊垂体中表达,利用原位杂交技术进一步确定MTNR1a基因在垂体中表达分布。结果提示,垂体是褪黑激素作用的靶器官,褪黑激素对绒山羊季节性繁殖的影响有可能是与垂体分泌的某些激素相互作用而发挥作用的。     

新牛蛙活性肽Catesbeianin-1a的抗菌抗肿瘤作用

通过筛选牛蛙皮肤cDNA文库得到具有较强抗菌抗肿瘤活性肽Catesbeianin-1a,合成其成熟肽氨基酸序列,MIC法测定抑菌活性结果表明,Catesbeianin-1a对临床常见的致病菌具有较强的抑菌活性,其中对猪链球菌2型的MIC为2.5mg/L,且对兔红细胞几乎无溶血性。MTT法测定多肽抗肿瘤细胞活性,结果 Catesbeianin-1a对胃癌细胞和肝癌细胞的抑杀活性很强,对肝癌细胞SGC7901的IC50为0.845mg/L。制作透射电镜超薄切片,利用透射电镜观察活性肽对细菌和肿瘤细胞超微结构的影响,旨在初步探讨牛蛙皮肤活性肽Catesbeianin-1a抗菌、抗肿瘤的作用机制,并以Catesbeianin-1a为基础进行分子改造来提高其抗肿瘤的靶向性并降低其毒性。     

商会自治的基石——商会自治规范研究

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。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

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。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

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。     

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.