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961.
962.
963.
为了探讨饲料可消化能值同饲料营养成分之间的关系,用Cr2O3作指示物,分别测定了鱼粉和大豆粕等饲料原料的草鱼(Ctenopharyngodon idella)团头鲂(Megalobrama amblyocephala Yih)青鱼(Myloparyngodon piceus)鱼种饲料的可消化能,用微机计算分析测试结果,发现饲料可消化能值随饲料蛋白质和/或脂肪食量增加而增加;随饲料无氮浸出物和/或纤维含量增加而降低。同时,“优选”出了有一定实用价值的估算草鱼、团头鲂和青鱼鱼种饲料可消化能值的回归方程。 相似文献
964.
利用PCR技术检测孕早期先天性沙眼衣原体感染 总被引:3,自引:0,他引:3
先天性感染已成为引起出生缺陷的重要原因,据调查,约有2—8%的新生儿受到先天性感染的影响〔1〕。由风疹病毒等感染引起的先天性感染已逐步为人们所重视,但由沙眼衣原体(Chlamydiatrachomatis,Ct)引起的先天性感染尚鲜为人知。本研究利用... 相似文献
965.
同步辐射小角X射线散射(SAXS)实验站所用的探测器由原来的NaI闪烁计数器改为位置灵敏探测器,其位置分辨好于100 μm,有效探测面积为50 mm×10 mm,得到了较以往更高质量的SAXS谱,并成功地对液体样品的SAXS谱进行了测试. 相似文献
966.
INTR0DUCTI0NIn0urprevi0usstudy0fV5andVKfromfouranti-TCSIgEhybrid0masestab-lishedin0urlaboratory,wefoundVKfr0mallfourcl0nesusedfragmentsfromthesamegermlinegenefamilyVK21,andabiasintheuse0fJk1genefragmentwasalsoobserved.Ontheotherhand,thegeneusageofVHwaJsquitediverse.WespeculatedthatinIgEresponsest0TCS,thelightchainmayplayam0reimpor-tantroleinspecificbindingtoallergenicdeterminant0nTCS[1].However,duet0thelimitationofhybrid0matechnology,itisdifficulttoachievealargenumberofanti-TCSI… 相似文献
967.
Human gastric cancer MKN-45 cells were transfected with pULB 3238,a plasmid carrying MVMp MS-1 gene with its original P4 promoter replaced by the glucocorticoid inducible promoter MMTV-LTR.After the integration and expression of NS-1 gene,some of the transfectants died,while others remained alive,but the growth features of survived cells were changed.For further study on the antineoplastic function of parvoviral NS-1 protein in vivo,transgenic mice carrying NS-1 genes were established by conventional method.Among 4 founders,one of them was found to be able to transmit the transgene to around 50% of their offsprings.RT-PCR was performed to indicate the expression of NS-1 gene in transgenic mice and its mRNA appeared in a variety of tissues.The expression of integrated NS-1 gene may correlate with the decreased incidence of tumor induced in vivo by chemical carcinogens. 相似文献
968.
A cDNA coding mutated cecropin CMIV from Bombyx mori was synthesized according to its amino acid sequense using E .coli biased codons .The gene was cloned into the fusion expression vector pEZZ318 and was expressed in E .coli HB101.The fusion protein produced was purified by affinity chromatography to yield 26 mg/L fusion product .The anti-bacterial activities of recombinant cecropin CMIV were recovered after cleavage by chemical method. 相似文献
969.
Using genomic in-situ hybridization (GISH) technique, 7 translocation-addition lines, 6 transloca-tion and translocation-addition lines, 2 ditelosomic addition lines and 1 translocation line were identified from Triticum aestivum L.-Psathyrostachys juncea (Fisch. ) Nevski intergeneric hybrids, of which translocation-addition and translocation and translocation-addition lines were not found in other reports. No substitutions and disomic additions were detected in the hybrids and breakages occurred in all P. juncea chromosomes studied. Results have shown that the improved GISH technique is a rapid and economical method for use in this field. 相似文献
970.
A cDNA coding mutated cecropin CMIV fromBombyx mori was synthesized according to its amino acid sequence usingE. coli biased codons. The gene was cloned into the fusion expression vector pEZZ318 and was expressed inE. coli HB101. The fusion protein produced was purified by affinity chromatography to yield 26 mg/L fusion product. The anti-bacterial
activities of recombinant cecropin CMIV were recovered after cleavage by chemical method. 相似文献