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991.
从发生在四川、重庆等省市的斑点叉尾妇急性流行性传染病病鱼的肝脏、肾脏内分离到1株高致病性菌株(CCF00024),人工感染健康鱼表现出与自然痛鱼相同的症状,并从中分离获得同种细菌,证实其为斑点叉尾鲴急性流行性传染病的病原菌。形态、生理生化检测表明,该菌为非发酵型直杆菌,严格需氧,革兰氏阴性,极生多鞭毛,对除麦芽糖和甘露糖以外的多种糖类不利用产酸,氧化酶阴性,DNA酶、蛋白酶、脲酶、赖氨酸脱羧酶阳性,MR、VP阴性。在以该菌16SrDNA序列(GenBank登录号AY970826)和GenBank及RDP数据库内同源性较高的细菌16SrDNA序列构建的系统发育树中,分离菌CCF00024与嗜麦芽寡养单胞菌(Stenotrophomonasmaltophilia)聚在一簇,特剐是与5.maltophiliaM5—1的同源性最高,序列相似性达99.6%,结合形态和生理生化特点将其鉴定为嗜麦芽寡养单胞菌(Stenotrophomonasmaltophilia)。药敏试验结果表明,对磺胺甲口恶唑、磺胺异口恶唑、阿齐霉素、洛美沙星高度敏感,而对新霉素、卡那霉素、氨苄青霉素、头孢唑啉、先锋霉素V和链霉素不敏感。 相似文献
992.
Garner BC Wiedmeyer CE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(3):240-244
Background: It has been speculated that renal disease can be identified through the detection and quantification of microalbuminuria, however, reliable measurement of albuminuria in any quantity can be challenging. Recently, a new point‐of‐care immunoassay was validated for the specific detection of microalbuminuria and early renal disease in dogs. Objectives: The goal of this study was to determine if measurement of microalbuminuria by the point‐of‐care immunoassay correlated with results from routine semiquantitative methods for detecting proteinuria in dogs. Methods: One hundred and thirty‐eight urine samples, from 133 different dogs, submitted for urinalysis to the Clinical Pathology Laboratory at the University of Missouri‐Columbia Veterinary Medical Teaching Hospital were eligible for the study. Samples that contained >20 RBC/high power field (hpf) or >20 WBC/hpf were excluded, as were samples with insufficient volume to complete all tests. All samples were evaluated with a urinary dipstick with or without a sulfosalicylic acid turbidimetric test, a urine protein:creatinine (UPC) ratio, and the immunoassay for microalbuminuria. Data were analyzed by the Spearman rank order correlation. Results: Microalbuminuria results correlated significantly with those of the dipstick (r= 0.715), sulfosalicylic acid test (r= 0.742), and UPC ratio (r= 0.830). Correlation between the immunoassay and UPC ratio was the same (r= 0.830) when only samples with trace or 1+ proteinuria by dipstick were analyzed (n = 51). Conclusions: The point‐of‐care immunoassay results for microalbuminuria correlated with the results of semiquantitative methods for detecting total proteinuria in dogs. Routine methods for canine proteinuria appear to be adequate for determining whether further testing for renal disease is warranted. 相似文献
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Commercial development of Trichoderma species for control of soil-borne vegetable diseases and their integration into standard crop management practices
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Kirstin L McLean John S Hunt Alison Stewart 《浙江大学学报(农业与生命科学版)》2004,30(4):407-407
A 10 year research programme at Lincoln University, investigating the use of Trichoderma species for biological control of soil-borne diseases of vegetable crops, has resulted in the development of two commercial products. Trichodry TM. 6S and Trichoflow TM. 6S based upon Trichoderma hamatum isolate 6SR4, are used to control Sclerotinia lettuce drop disease. The Trichodry 6S product is formulated as a dry flake, which is incorporated into nursery seedling mix and the Trichoflow 6… 相似文献
996.
SUN Yan WANG Yun-yue HE Yue-qiu FAN Jing-hua CHEN Jian-bin ZHU You-yong 《中国农业科学(英文版)》2002,1(5):549-554
Genetic diversity of commercial and local rice cultivars in Yunnan Province was studied using the resistance gene analogue (RGA) based on resistance gene conserved sequences. The RGA analysis of 137cultivars was conducted by PCR amplification using three primers, i.e. S1/AS3, XLRR for/XLRR rev, and Pto-kin1/Pto-kin2, respectively. The results showed that both Indica and Japonica cultivars were genetically highly diverse. All cultivars were divided into 3 lineages according to the DNA band data at 96% dissimilarity,and into 20 lineages at 60% dissimilarity. The lineages were related to their genetic background and blast disease resistance with only a few exceptions. The RGA data can be useful in rice production by mixed-planting of different cultivars in the field and breeding of resistance cultivars by selecting different parental cultivars with great genetic diversity. 相似文献
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棉花黄萎病抗性遗传研究 总被引:39,自引:1,他引:39
棉花对黄萎病抗性的遗传方式迄今尚有争议,本试验应用了11个经过鉴定的抗,感亲本进行不同组合的杂交,用致病力强弱不同的菌系,采用单菌系和混合菌系接种,病菌孢子悬浮液接种和病菌毒素接种的方法,对各组合不同世代群体进行遗传分析,试验分1983-1985,1986-1988,1989-1991三轮连续进行,每轮试验所用的材料和方法不完全相同,所得试验结果相互吻合,并与前人研究结果有所不同,可以作为进一步研 相似文献
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