马属动物组织培养细胞和外周血淋巴细胞染色体制作方法——附马C显带方法

马属动物染色体标本的制备对兽医学的基础理论研究和临床及畜牧业繁育良种的应用都是很重要的。细胞是一切生物的基本结构单位。染色体是遗传物质的主要载体,是细胞遗传学研究的主要内容。从染色体的形态结构以及染色体和其它细胞器的关系来研究遗传规律,阐明发育、遗传、变异及进化等原理,这对畜牧兽医的发展将是有深远意义的。现将我们制备染色体标本的方法介绍如下。     

鸡染色体标本制备技术条件的优化

染色体是基因的载体，细胞的染色体数目和结构是重要的遗传学指标，基因定位的染色体原位杂交；染色体组型分析；受精过程中染色体的行为；核型观察等这些研究，制备染色体标本无疑是这些实验成功与否的先决条件。     

无特定病原体京白鸡的核型研究

采用腹腔注射秋水仙素,取骨髓细胞制备染色体标本,对无特定病原体京白鸡的核型进行了分析.并根据前10对染色体相对长度、臂比值及着丝点指数的测量结果,与已公布的其它地方鸡品种进行了比较.     

小鼠骨髓染色体G显带最佳制备方法的探究

[目的]介绍一种改进的染色体G显带标本制备技术。[方法]采用小鼠骨髓细胞，改进取材方法、玻片的制备、胰酶处理时间以及染色方法等关键步骤，获得了染色体标本制备的最佳处理条件和试验方法。[结果]获得了更多的分散较好的分裂相，建立了一套实用性强、带型清晰、结果稳定、简单易行的染色体G显带制片技术。[结论]结果为规范小鼠染色体标本的制备方法，提高实验教学效果提供了参考。     

钉螺染色体核型研究进展

近年来,在WHO倡导的血吸虫病二元化防治策略的指导下,对血吸虫中间宿主-钉螺的研究日渐深入。取材问题、秋水仙素浓度、低渗处理时间和染色体的制备方法是成功制备钉螺染色体标本的关键。钉螺染色体核型主要包括染色体的数目和染色体形态。地域差异或者不同地理种群是造成染色体核型差异的主要原因,染色体显带技术的发展,为钉螺染色体核型研究提供了技术基础。论文对钉螺染色体核型研究进行综述。     

鸡与鹌鹑染色体核型比较研究

采用外周血淋巴细胞培养法制备染色体标本,对鸡与鹌鹑染色体核型进行研究。结果显示:鸡和鹌鹑染色体数目均为2n=78,但染色体形态存在差异,主要表现在No.1、No.4、No.6、No.8和W染色体上。No.1染色体,鸡为m型,鹌鹑为sm型;No.4染色体鸡为sm型,鹌鹑为st型;No.6、No.8和W染色体,鸡分别为sm、m、m型,鹌鹑全为t型。     

鱼类染色体制备方法概述

染色体是遗传物质的主要载体,几乎所有的染色体研究都离不开染色体标本的制备,随着各种生物技术的不断发展,鱼类染色体制备方法也不断完善,本文主要介绍鱼类几种主要的染色体制备方法。     

桑树有丝分裂染色体观察新法探索实验——酸解去壁低渗法

取桑芽、幼叶经前处理后,用1N HCl酸解处理材料15分钟,再进行低渗滴片,制备桑有丝分裂染色本标本.经观察,用此法制备的染色体标本,同样可以达到酶解去壁低渗法的观察效果,而比酶解去壁低渗法极大的节约实验费用;与常规切片法、压片法相比,其染色体制备效果好,且操作程序更简捷.将该方法称作桑树酸解去壁低渗法.     

野家牦牛染色体组型的比较研究

研究采用外周血淋巴细胞短期培养与气干法制备染色体标本,对野牦牛、家牦牛染色体进行核型分析比较,结果表明野牦牛和家牦牛二倍体细胞染色体数目相等,均为2n=60,雄性为29对常染色体和一对性染色体XY,雌性为29对常染色体和一对性染色体XX,根据测算结果常染色休勾端着丝点,性染色休XX和XY均为亚端着丝点染色体.     

乾华肉用美利奴羊的染色体核型研究及G-带分析

旨在研究新品种乾华肉用美利奴羊染色体的核型和G-带,揭示该品种的染色体数目和结构变异特征.采用外周血淋巴细胞培养法及常规染色体标本制备技术,分析染色体核型和G-带.结果表明,乾华肉用美利奴羊二倍体染色体数目为2n=54,26对常染色体中有3对为中着丝粒染色体,23对端着丝粒染色体;在性染色体中,X染色体为最大的端着丝粒...     

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.