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991.
文章介绍了一种全新的教学模式——数控加工一体化教学模式,从他的内涵出发,分析了其在实践中所具有的优势,发现其中的不足,并提出一些参考性意见,希望能为数控人才的培养提供参考,促进数控机床加工技术的发展进步。 相似文献
992.
993.
ZHANG Zhi CHENG Xiao-na FAN Ya-ting DONG Ya-qin LIU Shuang WU Fa-xing SHAO Wei-xing LI Xiao-cheng 《中国畜牧兽医》2015,42(7):1654-1660
To ascertain a diarrhea case in a pig farm in Shandong province,the pathological changes of dead piglets were observed and nested RT-PCR test was carried out on 7 diarrhea samples for porcine epidemic diarrhea virus (PEDV).Pathological examination revealed that intestine was detected as enlargement,hyperemia and edema.After histological examination,the typical microscopic lesions of intestine were disappearance of epithelial cells,villus shrinkage and shortening.The result of nested RT-PCR showed that all of the 7 samples could amplify a specific target band of PEDV.Molecular characteristics of two field strains showed that they had an amino acid homology of 92.3% to 92.4% with vaccine CV777 and 96.6% to 98.6% with other previous field strains which sequences were downloaded from GenBank.Phylogenetic tree analysis further revealed that all of PEDV strains could be mainly divided into two clusters of G1 and G2. G2 consisted of the field strains of our study and other field strains from USA,China and so on,which had the same sequence characteristics of two insertions and one deletion,while G1 consisted of all vaccines of CV777 and several older field strains from China and Korea.These results indicated that our field strains were the dominant strains in recent epidemic diarrhea occurrence.Moreover,its molecular characteristics might be a characterization of differentiating the field and vaccine strains. 相似文献
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995.
996.
TAO Li LAN Xian-li LI Jun MA Chun-xia LAN Jin-hong HUANG Ming-xue LAN Mei-yi BI Bing-fen CHEN Ze-xiang YANG Wei 《中国畜牧兽医》2016,43(4):1072-1078
To investigate the pathogens of goat's respiratory disease from a goat farm in Guangxi province, the epidemiological investigation, clinic observation, pathological examination, bacterium isolation and identification, biochemical test, PCR and animal experiment test were conducted.The preventive and control measures were taken on the basis of pathogen epidemiological characteristics and drug sensitive test results.The results showed that Mycoplasma, influenza virus and parasite were negative by isolation and culture or PCR, however, two strains of gram-negative bacteria named MS1 and MS2 were isolated from lung.MS1 was identified as Serratia marcescens by biochemical test and 16S rRNA sequencing, which shared 99% nucleotide homology with other Serratia marcescens in GenBank.And MS2 was identified as E.coil by the same methods that shared 99% nucleotide homology with other E.coli in GenBank.Animal experiment showed that two strains could cause death in mice.The drug sensitive tests showed two strains were highly sensitive to spectinomycin, amikacin, kanamicin and neomycin.Kanamycin and dexamethasone were used to treat the sick goats, and achieved good results. 相似文献
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998.
文章以武汉职业技术学院为例,对高职酒店管理专业“管培生”项目班的现状及存在的困境进行了分析,并提出了相应的对策。 相似文献
999.
复合酶制剂对陕北绒山羊增重效果的研究 总被引:2,自引:0,他引:2
选择健康陕北白绒山羊断奶羊63只,随机分为7组,每组9只.试验1、2、3组为酶制剂组,分别在日粮中添加0.075%、0.1%和0.125%的复合酶,试验4、5、6组为酶制剂十益生素组,分别在日粮中添加0.075%、0.1%和0.125%的复合酶和益生素的复合物,对照组按常规日粮饲喂,研究饲料复合酶制剂和复合酶制剂和益生素混合物添加不同量对陕北白绒山羊生产性能的影响.结果表明,经过73 d的饲喂试验,6个试验组平均增重均高于对照组,其中试验5组与对照组相比,增重增加1.73 kg,增加40.9%,差异极显著(P<0.01).试验2组比对照组多增重1.68kg,增加39.72%,差异显著(P<0.05). 相似文献
1000.
浙蒲8号是以自交系G7-4-3-1-2-1为母本、自交系J63-1-6-3-2-1为父本配制而成的耐热瓠瓜一代杂种。植株生长势较强,早中熟,以侧蔓结瓜为主,坐瓜性较好。商品瓜中棒形,上下粗细较均匀,平均瓜长约30cm,横径约5cm,瓜皮绿色,具光泽,单瓜质量0.4~0.5kg。耐高温性较强,高温期商品瓜率较对照杭州长瓜高6个百分点;品质佳,游离氨基酸总量1304.193μg·g-1,其中谷氨酸含量85.663μg·g-1;田间对枯萎病和白粉病的抗性强于对照杭州长瓜。适宜作露地栽培和夏秋季设施避雨栽培,夏秋季栽培每667m2产量2600kg以上。 相似文献