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排序方式: 共有417条查询结果,搜索用时 859 毫秒
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摘要:对皇帝蕉芽的消毒方法、外植体的诱导、幼芽的增殖培养、生根培养等进行了研究。结果表明:采用75%酒精60s--0.1%升汞12min(第一次8min 第二次4 min)的消毒方法,比较适宜于皇帝蕉外植体的消毒,易获得理想的无菌体系;在芽的诱导初期阶段,6-BA浓度采用5.0 mg/L,最适合皇帝蕉外植体的诱导;在幼芽的中高代增殖培养阶段,适宜采用MS 4.0mg/L6-BA 0.1mg/LNAA配方;在幼芽的高代增殖培养阶段,适宜采用MS 3.0mg/L6-BA 0.1mg/LNAA配方;在幼芽的生根阶段,适宜采用MS 2.5mg/LIBA 0.2mg/LNAA配方,幼苗生根快、根系壮实、发达,成活率高。 相似文献
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Kelsey A. Johnson James Sutherland-Smith Trisha J. Oura Amy F. Sato Bruce Barton 《Veterinary radiology & ultrasound》2023,64(1):86-94
Evaluation of brain disease in veterinary patients uses a wide variety of MRI sequences. A shortened protocol that maintains consistency of interpretation would reduce radiologist reporting time, patient anesthetic time, and client cost. The aims of this retrospective, methods comparison, observer agreement study were to evaluate whether abbreviated MRI protocols alter differential diagnoses and recommendations compared to our institution's standard protocol; evaluate interobserver agreement on standard brain MRIs; and assess whether differential diagnoses change after postcontrast images. Normal and pathologic canine and feline brain MRIs were retrieved from hospital archives. Three protocols were created from each: a 5-sequence noncontrast enhanced Fast Brain Protocol 1 (FBP1); a 6-sequence contrast-enhanced Fast Brain Protocol 2 (FBP2); and an 11-sequence standard brain protocol (SBP). Three blinded veterinary radiologists interpreted FBP images for 98 cases (1 reader/case) and SBP images for 20 cases (3 readers/case). A fourth observer compared these interpretations to the original MRI reports (OMR). Overall agreement between FBPs and OMR was good (k = 0.75) and comparable to interobserver agreement for multiple reviews of SBP cases. Postcontrast images substantially altered conclusions in 17/97 cases (17.5%), as well as improved interobserver agreement compared to noncontrast studies. The conclusions reached with shortened brain protocols were comparable to those of a full brain study. The findings supported the use of a 6-sequence brain MRI protocol (sagittal T2-weighted [T2w] TSE; transverse T2w turbo spin echo fluid-attenuated inversion recovery, T2*-weighted gradient recalled echo, T1-weighted spin echo, and diffusion weighted imaging/apparent diffusion coefficient; and postcontrast transverse T1-weighted spin echo) for dogs and cats with suspected intracranial disease. 相似文献
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C. Caprari C. Bergmann Q. Migheli G. Salvi P. Albersheim A. Darvill F. Cervone G. De Lorenzo 《Physiological and Molecular Plant Pathology》1993,43(6)
Extracellular endopolygalacturonase, purified from the pathogenic fungus Fusarium moniliforme, consists of four molecular forms (38, 41·5, 45, and 48·5 kDa, respectively. Three forms (38, 41·5, and 45 kDa) were purified to homogencity by FPLC on a Mono S column followed by electroelution after SDS-PAGE. The N-terminal amino acid sequences of each of the three forms, and of a mixture containing all four forms were shown to be identical to that predicted from the nucleotide sequence of the endopolygalacturonase gene previously cloned from F. moniliforme. Enzymatic deglycosylation experiments revealed the presence of N-linked, high mannose oligosaccharide side-chains on all four forms of endo polygalacturonase. Hydrogen fluoride catalysed chemical deglycosylation of the polygalacturonase mixture yielded a single polypeptide with an apparent molecular mass of 36·2 kDa. Southern blot analysis, carried out at high stringency with an endopolygalacturonase-specific probe on genomic DNA digested with three different restriction enzymes, showed a single hybridizing restriction fragment in all three digests. A single 2·0 Mb chromosome hybridized with the endo polygalacturonase-specific probe, as shown by Southern blot analysis of F. moniliforme chromosomes separated by CHEF electrophoresis. Northern blot analysis revealed only one mRNA species 1350 nt encoding endo polygalacturonase. These data indicate that a single gene encodes the endopolygalacturonases of F. moniliforme. 相似文献
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青岛梅园的建设及梅花品种的搜集与选育 总被引:3,自引:2,他引:1
在简介青岛梅园这一北方“新星”后,着重报道了其在建园中完成的两项科研成果,即①梅园快速规划设计与施工;②梅花品种的搜集、整理与新品种选育 相似文献
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Mohammed Anwar Hossain Daisuke Ikeda Akira Nomura Hideto Fukushima Shugo Watabe 《Fisheries Science》2008,74(4):921-934
ABSTRACT: The complete cDNA sequences encoding predominant types of myosin heavy chain (MYH) in the fast skeletal muscle were determined for brushtooth lizardfish Saurida undosquamis and wanieso lizardfish S. wanieso , which are used as materials for preparing high-quality surimi-based products. The cDNA consisted of 5973 and 5987 bp, respectively, and both encompassed an open reading frame encoding a polypeptide of 1936 amino acid residues. Brushtooth and wanieso lizardfish MYH showed the amino acid sequence identity of 92–93% to white croaker MYH, which was higher than that of 90% to walleye pollack MYH. The putative binding sites for ATP, actin, and regulatory and essential light chains in the subfragment-1 region of brushtooth lizardfish MYH exhibited a high identity with white croaker counterparts as well as the sequences of subfragment-2 and light meromyosin. In contrast, phylogenetic tree, constructed by the neighbor-joining method based on mitochondrial 16S rRNA gene, revealed that the two lizardfish species formed a cluster with walleye pollack, which was paraphyletic with white croaker. Therefore, a good reputation for lizardfish and white croaker to have a high thermal-gel forming ability seemed to be reflected by MYH rather than biological similarity as revealed by the mitochondrial 16S rRNA gene. 相似文献
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通过对加工中心刀具布局及多功能车整体布局的分析,提出了可行的作业头布局方式.结合作业头布局特点,分析了快速接口的设计要求,提出了可行的快速接口结构形式. 相似文献