Genotyping of Mycobacterium bovis by geographic location within Mexico   总被引：1，自引：0，他引：1  

Milián-Suazo F  Banda-Ruíz V  Ramírez-Casillas C  Arriaga-Díaz C 《Preventive veterinary medicine》2002,55(4):e129-264

The spacer oligonucleotide typing (spoligotyping) method was used to differentiate 62 Mycobacterium bovis isolates obtained from tissues with macroscopic lesions typical of tuberculosis in dairy cattle from different regions of Mexico. Our purpose was to see if a strain from one region was genetically different from those of other regions (with the long-term aim of doing molecular trace back of isolates obtained in the laboratory). Results from the genetic analysis indicate that M. bovis isolates cannot be grouped by geographic location due to a wide range of genetic types involved in dairy cattle infections. Isolates even from the same herd showed different spoligotypes but some isolates from different region had similar genetic patterns. Genetic typing without epidemiologic information does not seem to be a plausible method to trace back animals to source of origin to detect and eliminate sources of infection.  相似文献   

尾叶桉胚状体植株诱导与增殖研究   总被引：6，自引：1，他引：6  

王米力  曾平安 《四川林业科技》1996,17(2):9-13

本文报导了用尾叶桉种子下胚胎诱导体细胞胚胎发生，获得根苗齐全的胚状体再生植株，经过５～６代增殖培养，获得大量丛生苗，已完成移栽，炼苗的全套生产技术流程，是迄今世界松树组培由下胚轴产生胚状体小苗成功的第三例，在木本植物的同类组培成功研究中也是数例之一，在科学和林木良种快速选育与繁殖上有重要价值。  相似文献   

Influence of diet and feeding strategy on the performance of nitrifying trickling filter,oxygen consumption and ammonia excretion of gilthead sea bream (Sparus aurata) raised in recirculating aquaculture systems     

Godoy-Olmos  Sergio  Jauralde  Ignacio  Monge-Ortiz  Raquel  Milián-Sorribes  María C.  Jover-Cerdá  Miguel  Tomás-Vidal  Ana  Martínez-Llorens  Silvia 《Aquaculture International》2022,30(2):581-606

Gilthead sea bream (Sparus aurata) was raised in six individual recirculating aquaculture systems (RAS) whose biofilters’ performance was analyzed. Fish were fed with three different diets (a control diet, a fishmeal-based diet (FM), and a plant meal-based diet (VM)) and with three different feeding strategies (manual feeding to apparent satiation, automatic feeding with restricted ration, and auto-demand feeding). For every combination of diet and feeding strategy, the mean oxygen consumption, ammonia excretion, and ammonia removal rate were determined. Fish fed with the VM diet consumed the most oxygen (20.06?±?1.80 gO₂ consumed kg^?1 day^?1). There were significant differences in ammonia excretion depending on the protein content and protein efficiency of the diet, as well as depending on feeding strategy, which in turn affected ammonia removal rates. Fish fed by auto-demand feeders led to the highest mean ammonia removal rate (0.10 gN-TAN removed m^?2 biofiltration area day^?1), while not leading to peaks of high ammonia concentration in water, which preserve fish welfare and growth.

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Melanoidins and carbohydrates in roasted barley.     

B L Mili?  B Gruji?-Injac  M V Pileti?  S Lajsi?  L A Kolarov 《Journal of agricultural and food chemistry》1975,23(5):960-963

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四川松杉植物细胞学研究及生物学意义     

王米力  石大兴 《四川农业大学学报》1996,14(3):444-448

本文首次讨论了四川松杉植物细胞学研究现状及核型资料应用于系统分类、植物区系研究的生物学意义和林学意义以及染色体技术在优良品种选育及无性系鉴定中的应用前景。  相似文献   

植物组织培养中控制污染技术研究   总被引：26，自引：0，他引：26  

李群  杜文平 《四川林业科技》1999,20(4):22-26

本文在总结分析近２０ 年来植物组织培养中有关污染的文献的基础上,结合笔者在桉树、月季、红豆杉、一品红等植物的组培研究中的体会,针对污染的原因、影响因素,首次系统地提出了控制或降低污染率的有效途径,为组培中提高得率提供了一定的理论和实践依据,在科研及生产上有一定的实用价值。  相似文献   

Genetic diversity of rhizobia associated with alfalfa in Serbian soils     

Olivera Stajkovi?-Srbinovi?  Sofie E. De Meyer  Bogi? Mili?i?  Du?ica Deli?  Anne Willems 《Biology and Fertility of Soils》2012,48(5):531-545

We have evaluated the genetic diversity and phylogeny of alfalfa rhizobia, originating from different types of soils in Serbia and their ability to establish an effective symbiosis with alfalfa (Medicago sativa L.). A collection of 65 strains isolated from root nodules of alfalfa were characterized by rep-PCR analysis, partial and complete 16S rDNA gene and recA gene sequencing, as well as atpD gene sequencing and DNA–DNA hybridizations. The results of the sequence analyses revealed that Sinorhizobium meliloti is the dominant species in alfalfa nodules. Only one strain was identified as Sinorhizobium medicae, two strains as Rhizobium tibeticum and one strain as Rhizobium sp. Despite the fact that the majority of strains were identified as S. meliloti, a high genetic diversity at strain level was detected. Almost all isolates shared the ability to nodulate and fix nitrogen with M. sativa, except 11 of them, which were incapable of fixing nitrogen with this species. About 50% of the isolates showed values of symbiotic effectiveness (SE) above 50%, while 10% of the strains were highly effective with SE values above 70%. Some of the strains which were highly effective in nitrogen fixation at the same time could intensively solubilize phosphates, offering a possibility for multipurpose inoculum development. This was the first genetic study of rhizobia isolated from this region and also the first report of natural presence of R. tibeticum in root nodules of M. sativa.  相似文献   

连香树离体快繁初步研究   总被引：1，自引：0，他引：1  

麦苗苗  石大兴  王米力  廖静  韩珊 《园艺学报》2006,33(1):186-189

 连香树为我国珍稀濒危树种, 具有较高的经济价值和观赏价值。本文研究了3年生连香树(Cercidiphyllum japonicum Sieb. et Zucc. ) 带芽茎段的离体培养。筛选出最佳培养基: (1) 腋芽诱导培养基: MS +NAA 0.01 mg·L ^{- 1} ; (2) 丛生芽诱导培养基: MS +BA 1.0 mg·L ^{- 1} ; (3) 丛生芽增殖培养基:MS +BA 2.0 mg·L ^{- 1} + 2,4-D 0.01 mg·L ^{- 1} ; (4) 生根培养基: 1 /2MS + IBA 1.0 mg·L ^{- 1}。  相似文献   

中国西部六种特有松科植物核型及细胞地理学研究   总被引：4，自引：0，他引：4  

石大兴  王米力 《四川农业大学学报》1994,12(1):84-91

本文分析的麦吊云杉、峨眉冷杉等４种２变种松科植物属我国特有种，主产中国西部，观察到的根尖细胞核型有５种为首次报导。麦吊云杉（Ｐｉｃｅａｂｒａｃｈｙｔｙｌａ）和变种油麦吊云杉（Ｐ．ｂ．ｖａｒ．ｃｏｍｐｌａｎａｔａ）为２Ａ核型，Ｋ（２ｎ）＝２４＝２０ｍ＋４ｓｍ；天山云杉（Ｐ．ｓｃｈｒｅｎｋｉａｎａｖａｒ．ｆｉａｎｓｈａｎｉｃａ）为２Ｂ核型，Ｋ（２ｎ＝２４＝１６ｍ＋８ｓｍ；峨眉冷杉（Ａｂｉｅｓｆａｂｒｉ）为２Ａ模型，Ｋ（２ｎ）＝２４＝１４ｍ＋８ｓｍ＋２ｓｔ；红杉（Ｌａｒｉｘｐｏｔａｎｉｎｉｉ）为２Ａ核型，ｋ（２ｎ）＝２４＝１２ｍ＋１０ｓｍ＋２ｓｔ；高山松（Ｐｉｎｕｓｄｅｎｓａｔａ）为１Ａ核型，ｋ（２ｎ）＝２４＝２４ｍ。试材来源于原始林区的自然居群，根据核型资料，结合各种的生态、地理分布，进行了遗传变异及进化程度的讨论。  相似文献   

岷江柏木和西藏柏木的核型及亲缘关系研究   总被引：3，自引：0，他引：3  

石大兴  王米力 《四川农业大学学报》1994,12(1):92-96

本文首次报导了岷江柏木（Ｃｕｒｐｒｅｓｓｕｓｃｈｅｎｇｉａｎａ）和西藏柏木（Ｃｕｐｒｅｓｓｕｓｔｏｒｕｌｏｓａ）的体细胞核型。两种有相同的核型公式Ｋ（２ｎ）＝２２＝２０ｍ＋２ｓｍ，同属１Ａ核型，其它核型数据相近。岷江柏木为中国特有种，西藏柏木主产我国，结合生态、地理分布特征及生化分析资料，讨论了两者的亲缘关系及生态同群种的一致性趋势。  相似文献