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柳蚕卵黄原蛋白(Vg)cDNA3′端的克隆及序列分析 总被引：1，自引：1，他引：0
柳蚕(Actias seleneHbner)是野生泌丝昆虫。从柳蚕雌蛹脂肪体中提取总RNA,根据已经解析出的其它泌丝昆虫的卵黄原蛋白cDNA序列设计特异性引物,对柳蚕卵黄原蛋白cDNA3′端进行RACE(rapid amplification ofcDNA ends)扩增,经克隆和测序得到了一条1 072 bp的cDNA片段,该序列与柞蚕(Antheraea pernyi)、天蚕(An-theraea yamamai)、野桑蚕(Bombyxmandarina)、家蚕(Bombyxmori)、樗蚕(Samia cynthia pryeri)、蓖麻蚕(Philosamiacynthia ricini)、樟蚕(Saturnia japonica)相应序列的同源性分别为82.5%、82.4%、67.0%、63.2%、80.3%、78.5%、81.0%。同源性分析表明,昆虫卵黄原蛋白的一级结构在进化上具有较高的保守性。 相似文献
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柳蚕(Actias selene Hübner)是鳞翅目大蚕蛾科的一种珍稀野生绢丝昆虫.利用RT-PCR方法克隆了柳蚕丝素重链基因(Fib-H)cDNA 5'端的一个片段,该片段序列长819 bp, 编码273个氨基酸,含有4个保守多聚丙氨酸结构域.序列比对分析表明,该片段序列与樟蚕(Saturnia japonica)、天蚕(Antheraea yamamai)、柞蚕(Antheraea pernyi)、印度柞蚕(Antheraea mylitta)和家蚕(Bombyx mori) 的Fib-H基因cDNA 5'端同源序列的相似性分别为72.5%、65.8%、65.1%、65.1%、47.1%.半定量PCR分析显示柳蚕Fib-H基因cDNA 5'端片段序列在5龄幼虫第1-12天的表达量呈现逐渐上升的趋势. 相似文献
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基于丰富蓖麻蚕核型多角体病毒(Philosamia cynthia ricininucleopolyhedrovirus,PcrNPV)分子信息的目的,对PcrNPV DNA部分片段进行了测序分析,获得1个DNA结合蛋白基因p6.9的完整序列。该基因的读码框由240个核苷酸组成,编码79个氨基酸,分子质量约为9.8 kD,转录起始位点ATG侧翼序列符合Kozak规则,其上游34bp处具有晚期基因转录的保守起始序列taag,表明该基因为晚期表达基因。将PcrNPV与12种昆虫核型多角体病毒P6.9蛋白氨基酸序列作同源性比较的结果显示:PcrNPV P6.9蛋白氨基酸序列与家蚕(Bombyx mori)NPV P6.9的同源性为59%,与柞蚕(Antheraea pernyi)NPV的同源性为100%,表明PcrNPV与ApNPV的亲缘关系很近。 相似文献
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异柠檬酸脱氢酶(isocitrate dehydrogenase,IDH)是生物体内一种重要的氧化还原酶。根据已报道的烟酰胺腺嘌呤二核苷酸磷酸异柠檬酸脱氢酶(NADP-IDH)基因的保守性序列设计引物,以柳蚕(Actias seleneHubner)蛹脂肪体cDNA为模板,经PCR扩增获得了柳蚕IDH基因的部分序列。该序列长1 269 bp,编码412个氨基酸,与家蚕IDH基因的cDNA序列同源性达82.5%。柳蚕IDH与果蝇、赤拟谷盗、斑马鱼、人、大鼠、库蚊、人体虱、恶性疟原虫IDH的氨基酸序列同源性在70%左右,具有较高的保守性。半定量PCR检测结果表明,柳蚕IDH基因在蛹期不同组织中均有表达,且表达量没有显著差异。 相似文献
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柳蚕(Actias selene Hübner)是鳞翅目大蚕蛾科的一种珍稀野生绢丝昆虫。利用RT-PCR方法克隆了柳蚕丝素重链基因(Fib-H)cDNA 5′端的一个片段,该片段序列长819 bp,编码273个氨基酸,含有4个保守多聚丙氨酸结构域。序列比对分析表明,该片段序列与樟蚕(Saturnia japonica)、天蚕(Antheraea yamamai)、柞蚕(Antheraea pernyi)、印度柞蚕(Antheraea mylit-ta)和家蚕(Bombyxmori)的Fib-H基因cDNA 5′端同源序列的相似性分别为72.5%、65.8%、65.1%、65.1%、47.1%。半定量PCR分析显示柳蚕Fib-H基因cDNA 5′端片段序列在5龄幼虫第1-12天的表达量呈现逐渐上升的趋势。 相似文献
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绢丝昆虫卵黄原蛋白一级结构的特性分析 总被引：4，自引：4，他引：0
家蚕、天蚕、蓖麻蚕、柞蚕、野桑蚕、透目天蚕、樟蚕7种绢丝昆虫分别属于鳞翅目的家蚕蛾科和天蚕蛾科的不同属。通过对7种绢丝昆虫卵黄原蛋白一级结构保守序列如信号肽序列、多聚丝氨酸、糖基化位点等的比较和分析,并进一步根据氨基酸的同源性构建了系统树。结果证明了7种绢丝昆虫的卵黄原蛋白的一级结构在进化上具有很好的保守性,其中蓖麻蚕和樗蚕的亲缘关系最近,家蚕蛾科的野桑蚕和天蚕蛾科的樟蚕的亲缘关系最远。 相似文献
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樗蚕(Philosamia cynthia cynthia)与蓖麻蚕(Philosamia cynthia ricini)均是鳞翅目大蚕蛾科吐丝营茧的昆虫,二者的血缘关系很近,成虫的外形也极其相似。为了获得用于樗蚕与蓖麻蚕分子鉴定的DNA条形编码,测定了二者的线粒体细胞色素酶C亚基I基因(COI)574 bp的DNA片段序列(GenBank登录号:FJ788507,FJ772004),对序列特征及与同科其它绢丝昆虫同源序列的系统进化关系进行了分析。在大蚕蛾科绢丝昆虫中,樗蚕与蓖麻蚕COI序列表现出最强的碱基T偏好性(ATskew=-0.194),二者的COI序列之间具有明显差异,共鉴定出25个变异位点,表明所测定COI序列可以作为各自的DNA条形编码。樗蚕与蓖麻蚕之间基于Kimura-2-Parameter的遗传距离为0.041,而与同科其它绢丝昆虫之间的遗传距离则在0.076~0.159之间,二者与惜古比天蚕(Hyalophora ce-cropia)之间的亲缘关系较近。 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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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。 相似文献