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611.
A carbohydrate-derivative alkylcobalt carbonyl,([(1,2:5,6-di-O,O-isopropylidene-alpha-D-glucofuranos-3-yl)oxycarbonyl]methyl)cobalt tricarbonyl triphenylphosphene(3) was prepared and characterized by IR, NMR, and CD spectra, as well as by X-ray diffraction. The supramolecular chemistry in the crystalline P2(1)2(1)2(1) (chiral) phase and in solution was analyzed and compared. The bulky carbohydrate-based ligand stabilized one chiral conformation, which, however, is less ordered than for analogous compounds with more flexible and less bulky chiral groups. Intermolecular, H-bond interactions are more important in the P2(1)2(1)2(1) phase of complex 3 than at other analogous compounds. 相似文献
612.
Zucchi TD Bonda AN Frank S Kim BY Kshetrimayum JD Goodfellow M 《Antonie van Leeuwenhoek》2012,102(1):91-98
The status of two mesophilic filamentous actinomycetes isolated from an arid Australian soil sample was determined using a polyphasic taxonomic approach. The isolates had chemical and morphological properties consistent with their classification in the genus Amycolatopsis, assignments that were supported by analysis of 16S rRNA gene sequence data. Isolate SF26T formed a distinct phyletic line and hence was sharply separated from its nearest phylogenetic neighbour, Amycolatopsis sacchari DSM 44468T. In contrast, isolate SF27T formed a subclade in the Amycolatopsis tree with Amycolatopsis vancoresmycina DSM 44592T but was separated readily from the latter by DNA:DNA pairing data. The two isolates were distinguished from one another and from their respective nearest phylogenetic neighbours using a range of phenotypic properties. These data indicate that the two isolates should be recognized as new species in the genus Amycolatopsis. The names proposed for these new taxa are Amycolatopsis bartoniae sp. nov. and Amycolatopsis bullii sp. nov. with isolates SF26T (=NCIMB 14706T = NRRL B-2846T) and SF27T (=NCIMB 14707T = NRRL B-24847T) as the respective type strains. 相似文献
613.
Abreu AG Priolli RH Azevedo-Filho JA Nucci SM Zucchi MI Coelho RM Colombo CA 《Genetics and molecular biology》2012,35(1):119-121
Acrocomia aculeata is a perennial, fruit-producing palm tree, native to tropical forests. Its fruits have spurred interest because of their significant potential for use in the cosmetic industry and as feedstock for biofuel. In the present study, the genetic structure and mating system in Acrocomia aculeata were analyzed, using eight nuclear micro-satellite loci and samples from São Paulo and Minas Gerais states, Brazil. By means of Bayesian analysis, these populations were clustered into two or three groups. A high multilocus outcrossing rate suggests that outcrosses were predominant, although a certain degree of biparental inbreeding also occurred. Thus, although monoecious and self-compatible, there is every indication that A. aculeata bears a mixed reproductive system, with a predominance of outcrossing. Given the genetic structure revealed hereby, future conservation strategies and germplasm collecting should be focussed on sampling and preserving individuals from different clusters. 相似文献
614.
¿Neurologist's contribution to the diagnosis of sine materia respiratory insufficiency: case report¿
C Carbonelli M Zedde A Cavazza N Facciolongo F Menzella L Spaggiari L Zucchi 《BMC pulmonary medicine》2012,12(1):42
ABSTRACT: Right-to-left shunt (RLS) can be the reason of marked hypoxemia, this diagnosis of respiratory insufficiency is usually difficult to make by Respiratory Physicians as it develops in absence of an intrinsic lung disease. We report a case of RLS in a patient with a hepatopulmonary syndrome caused by chronic autoimmune cholangitis which was suspected clinically by physical examination and by standard CT imaging and MIP reconstruction of the pulmonary vascular bed. Repeated previous transthoracic echocardiography (TTE) studies didn't reveal the shunts. The final diagnosis was performed by a minimally invasive doppler transcranial examination with the use of agitated saline as contrast solution. Transcranial Colour-Coded Duplex Sonography (TCCS) with saline contrast medium injection is described to have an higher sensitivity compared with TTE and comparable with transesophageal echocardiography (TEE) in RLS diagnosis. The collaboration of Neurologists to this diagnosis of respiratory insufficiency is really important, as the examination is simple, well tolerated in comparison with the discomfort associated with transesophageal echocardiography, and of minimal invasivity in comparison with angiography which is the ultimate diagnostic procedure in this clinical scenario. TCCS with saline contrast medium injection, should be performed for the diagnosis of chronic hypoxemia for which causes are not detected with routine clinical examinations, in order to confirm RLS. 相似文献
615.
Chris Hawes 《植物学报(英文版)》2012,(11):838-839
<正>Organelles are eukaryotic subcellular structures each possessing a specific set of functions.The morphology,abundance,and content of the organelles also undergo constant changes for optimal function 相似文献
616.
617.
本文采用喷雾干燥法制备高纯α-亚麻酸为芯材、亚麻籽胶为壁材的微胶囊,并以微胶囊化效率和含油率为指标,考察了制备工艺.结果表明,最佳微胶囊原料配方为:芯材与壁材的比例为(m/m)3∶2,料液浓度为5%,进料温度为20℃;最佳喷雾干燥工艺条件:进风温度为180℃,出风温度为80℃,雾化器转速21000 rpm,进料速度为42.01 mL/min.在此工艺条件下亚麻酸的微胶囊化效率为96.18%,含油率为60.09%. 相似文献
618.
De Souza AR Lopes-Mielezrski GN Lopes EN Querino RB Corsato CD Giustolin TA Zucchi RA 《Environmental entomology》2012,41(2):233-237
The purpose of this study was to investigate native species of parasitoids of frugivorous larvae and their associations with host plants in commercial guava orchards and in typical native dry forests of a caatinga-cerrado ecotone in the State of Minas Gerais, Brazil. Nine species of parasitoids were associated with larvae of Anastrepha (Tephritidae) and Neosilba (Lonchaeidae) in fruit of Psidium guajava L. (Myrtaceae), Ziziphus joazeiro Mart. (Rhamnaceae), Spondias tuberosa Arruda (Anacardiaceae), Spondias dulcis Forst. (Anacardiaceae), Syzygium cumini (L.) Skeels (Myrtaceae), and Randia armata (Sw.) DC. (Rubiaceae). Doryctobracon areolatus was the most abundant species, obtained from puparia of Anastrepha zenildae, An. sororcula, An. fraterculus, An. obliqua, and An. turpiniae. This is the first report of Asobara obliqua in Brazil and of As. anastrephae and Tropideucoila weldi in dry forests of Minas Gerais State. The number of species of parasitoids was higher in areas with greater diversity of cultivated species and lower pesticide use. The forest fragments adjacent to the orchards served as shelter for parasitoids of frugivorous larvae. 相似文献
619.
620.
采用化学诱变剂乙酰基亚硝基脲(N-ethyl-N-nitrosourea,ENU)获得一种常染色体显性遗传多趾突变小鼠(Mus musculus),该突变小鼠在后趾内侧(即轴前部)多出一个脚趾,且严重程度不一,部分小鼠双侧后足都有多趾表型。阿尔新蓝-茜素红染色结果表明,多趾突变杂合子小鼠除多趾异常发育外,其余骨骼无明显异常。为定位该突变基因,利用微卫星标记对(C57BL/6J×DBA/2J)F1代多趾突变小鼠回交C57BL/6J得到的[(C57BL/6J×DBA/2J)F1×C57BL/6J]N2代多趾小鼠进行全基因组扫描,最终将本例多趾突变基因定位于小鼠第2号染色体微卫星D2mit45与D2mit184之间,并初步确定Alx4为该突变候选基因。在此基础上对Alx4进行测序分析,测序结果发现突变小鼠Alx4基因编码区第433位碱基处发生A到T的颠换,导致编码区第145位密码子AAA(编码赖氨酸)变为终止密码子TAA,引起蛋白编码提前终止,是引起多趾表型的原因。 相似文献