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排序方式: 共有706条查询结果,搜索用时 15 毫秒
51.
Selma Regina Penha Silva Cerqueira Patrícia Duarte Deps Dbora Vilela Cunha Natanael Victor Furtunato Bezerra Daniel Holanda Barroso Ana Brbara Sapienza Pinheiro Gecilmara Salviato Pillegi Taynah Alves Rocha Repsold Patrícia Shu Kurizky Simon M. Collin Ciro Martins Gomes 《PLoS neglected tropical diseases》2021,15(7)
52.
Teresa Lucena María A. Ruvira M. Carmen Macián María J. Pujalte David R. Arahal 《Antonie van Leeuwenhoek》2014,105(4):671-678
Strain 4SM10T, an aerobic marine, Gram-negative, heterotrophic and non pigmented bacterium isolated from seawater from Vinaroz in Castellón, Spain, was characterized using a polyphasic approach. Analysis of the 16S rRNA gene sequence placed the strain within the Roseobacter clade in the family Rhodobacteraceae. Phylogenetic analyses also showed that strain 4SM10T forms a stable clade with species of the genus Roseovarius, being related to Roseovarius nubinhibens ISMT and Roseovarius aestuarii SMK-122T at 97.5 and 97.4 % 16S rRNA sequence similarity, respectively. Average Nucleotide Identity (ANI) values, determined as a measure of overall genomic resemblance, confirmed that strain 4SM10T does not belong to the same species as R. aestuarii CECT 7745T and Roseovarius nubinhibens CECT 7750T displaying ANI values well below the 95 % boundary for genomic species. Strain 4SM10T requires Na+ plus a divalent cation (either Mg2+ or Ca2+) to grow, reduces nitrate to nitrite and uses a large number of amino acids and organic acids (but no carbohydrates) as sole carbon sources. Enzymatic activities displayed in API ZYM tests are alkaline phosphatase, leucine arylamidase and acid phosphatase. The major cellular fatty acids were identified as C18:1 ω7c and/or C18:1 ω6c (67.1 %). The DNA G+C content was determined to be 54.27 mol%. Based on the genotypic and phenotypic data obtained, the name Roseovarius albus sp. nov. is proposed for this novel taxon, with the type strain 4SM10T (=CECT 7450T = KCTC 22653T). 相似文献
53.
Bruna Martins Bezerra Antonio S. Souto Gareth Jones 《International journal of primatology》2010,31(5):759-778
The study of vocal behavior can reveal important aspects of how and why a species communicates in relation to ecological and
social challenges. We here focus on vocal communication in golden-backed uakaris (Cacajao melanocephalus), diurnal, pitheciine monkeys that exhibit fission-fusion social organization and typically inhabit dense forests that limit
the potential for visual communication. Moreover, the species spends little time engaged in tactile or olfactory communication,
e.g., social grooming and scent marking, respectively. Hence, vocalizations may be very important for the coordination of
social organization in these monkeys. We 1) categorized golden-backed uakari vocalizations, 2) ascertained their behavioral
context, and 3) investigated whether golden-backed uakari calls can encode information about the signaler. We observed the
monkeys during 2 wet seasons in the flooded igapó forest of Jaú National Park, Brazil. We showed that golden-backed uakaris
have 9 call types in their vocal repertoire, all distinguishable by ear and from analysis of spectrograms. Some calls, e.g.,
play-specific calls, were used only in particular behavioral contexts, and by individuals of specific age, whereas others
were emitted under a range of situations. The structure of the loud tchó call varied among individuals, and according to behavioral context, i.e., whether individuals were foraging/feeding, traveling,
or performing agonistic interactions. This knowledge of the species’ vocal repertoire is valuable for surveying the monkeys
acoustically in habitats where visual surveys are difficult. 相似文献
54.
55.
de Araújo MV Vieira EK Lázaro GS de Souza Conegero L Ferreira OP Almeida LS Barreto LS da Costa NB Gimenez IF 《Bioorganic & medicinal chemistry》2007,15(17):5752-5759
The inclusion complexation of pyrimethamine in 2-hydroxypropyl-beta-cyclodextrin has been investigated by 2D (1)H NMR, FTIR and UV/visible spectroscopy and also by molecular modelling methods (AM1, PM3, MM3). From the phase-solubility diagram a linear increase was observed in pyrimethamine aqueous solubility in the presence of 2-hydroxypropyl-beta-cyclodextrin, evidencing the formation of a soluble inclusion complex. According to the continuous variation method (Job's plot) applied to fluorescence measurements, a 1:1 stoichiometry has been proposed for the complex. Concerning the structure of the complex, a Cl-in orientation of pyrimethamine in the 2-hydroxypropyl-beta-cyclodextrin cavity has been proposed from the theoretical calculations, being confirmed by two-dimensional (1)H NMR spectroscopy (ROESY). The thermal behaviour has also been studied, providing complementary evidences of complex formation. 相似文献
56.
Bezerra GA Oliveira TM Moreno FB de Souza EP da Rocha BA Benevides RG Delatorre P de Azevedo WF Cavada BS 《Journal of structural biology》2007,160(2):168-176
Plant lectins, especially those purified from species of the Leguminosae family, represent the best studied group of carbohydrate-binding proteins. The legume lectins from Diocleinae subtribe are highly similar proteins that present significant differences in the potency/efficacy of their biological activities. The structural studies of the interactions between lectins and sugars may clarify the origin of the distinct biological activities observed in this high similar class of proteins. In this way, this work presents a crystallographic study of the ConM and CGL (agglutinins from Canavalia maritima and Canavalia gladiata, respectively) in the following complexes: ConM/CGL:Man(alpha1-2)Man(alpha1-O)Me, ConM/CGL:Man(alpha1-3)Man(alpha1-O)Me and ConM/CGL:Man(alpha1-4)Man(alpha1-O)Me, which crystallized in different conditions and space group from the native proteins. The structures were solved by molecular replacement, presenting satisfactory values for R(factor) and R(free). Comparisons between ConM, CGL and ConA (Canavalia ensiformis lectin) binding mode with the dimannosides in subject, presented different interactions patterns, which may account for a structural explanation of the distincts biological properties observed in the lectins of Diocleinae subtribe. 相似文献
57.
de Moura SA de Sousa JM Lima DF Negreiros AN Silva Fde V da Costa LJ 《Gerodontology》2007,24(3):173-176
Objective: The aim of the present study was to analyse the characteristics of salivary production and its composition in individuals with burning mouth syndrome (BMS). Study Design: Salivary flow rate, concentrations of potassium, iron, chloride, thiocyanate, magnesium, calcium, phosphorus, glucose, total protein and urea, as well as the expression profile of salivary proteins were analysed by SDS‐PAGE. Results: The mean salivary flow rate among control patients was lower than that of BMS patients. Chloride, phosphorus and potassium levels were elevated in patients with BMS (p = 0.041, 0.001 and 0.034, respectively). Total salivary protein concentration was reduced in individuals with BMS (p = 0.223). Analysis of the expression of salivary proteins by Coomassie blue SDS‐PAGE revealed a lower expression of low molecular weight proteins in individuals with BMS compared to healthy controls. Conclusions: These results indicate that the identification and characterisation of low molecular weight salivary proteins in BMS may be important in understanding BMS pathogenesis, thus contributing to its diagnosis and treatment. 相似文献
58.
Brain bank of the Brazilian aging brain study group—a milestone reached and more than 1,600 collected brains 总被引:2,自引:0,他引:2
Grinberg LT Ferretti RE Farfel JM Leite R Pasqualucci CA Rosemberg S Nitrini R Saldiva PH Filho WJ;Brazilian Aging Brain Study Group 《Cell and tissue banking》2007,8(2):151-162
INTRODUCTION: Brain banking remains a necessity for the study of aging brain processes and related neurodegenerative diseases. In the present paper, we report the methods applied at and the first results of the Brain Bank of the Brazilian Aging Brain Study Group (BBBABSG) which has two main aims: (1) To collect a large number of brains of elderly comprising non-demented subjects and a large spectrum of pathologies related to aging brain processes, (2) To provide quality material to a multidisciplinar research network unraveling multiple aspects of aging brain processes and related neurodegenerative diseases. METHODS: The subjects are selected from the Sao Paulo Autopsy Service. Brain parts are frozen and fixated. CSF, carotids, kidney, heart and blood are also collected and DNA is extracted. The neuropathological examinations are carried out based on accepted criteria, using immunohistochemistry. Functional status are assessed through a collateral source based on a clinical protocol. Protocols are approved by the local ethics committee and a written informed consent form is obtained. RESULTS: During the first 21 months, 1,602 samples were collected and were classified by Clinical Dementia Rating as CDR0: 65.7%; CDR0.5:12.6%, CDR1:8.2%, CDR2:5.4%, and CDR3:8.1%. On average, the cost for the processing each case stood at 400 US dollars. To date, 14 laboratories have been benefited by the BBBABSG. CONCLUSION: The high percentage of non- demented subjects and the ethnic diversity of this series may be significantly contributive toward aging brain processes and related neurodegenerative diseases understanding since BBBABSG outcomes may provide investigators the answers to some additional questions. 相似文献
59.
Fonseca Bárbara Medeiros Câmara Paulo Eduardo Aguiar Saraiva Ogaki Mayara Baptistucci Pinto Otávio Henrique Bezerra Lirio Juan Manuel Coria Silvia H. Vieira Rosemary Carvalho-Silva Micheline Amorim Eduardo Toledo Convey Peter Rosa Luiz Henrique 《Molecular biology reports》2022,49(1):179-188
Molecular Biology Reports - Vega Island is located off the eastern tip of the Antarctic Peninsula (Maritime Antarctica), in the Weddell Sea. In this study, we used metabarcoding to investigate... 相似文献
60.
Fernandes Jackellynne Fernanda Farias Freitas Jailza de Araújo Sandra Alves de Santana Thiago Campos Lobato Rafael Santos Figueiredo Marina Bezerra 《Environmental Biology of Fishes》2022,105(8):1033-1050
Environmental Biology of Fishes - To clarify the reproductive activity of lane snapper, Lutjanus synagris, a total of 359 specimens of lane snapper were collected in partnership with an artisanal... 相似文献