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71.
Merilane da Silva Calixto Izaquiel Santos de Andrade Diogo Cavalcanti Cabral-de-Mello Neide Santos Cesar Martins Vilma Loreto Maria José de Souza 《Genetica》2014,142(1):49-58
Chromosomal organization and the evolution of genome architecture can be investigated by physical mapping of the genes for 45S and 5S ribosomal DNAs (rDNAs) and by the analysis of telomeric sequences. We studied 12 species of bats belonging to four subfamilies of the family Phyllostomidae in order to correlate patterns of distribution of heterochromatin and the multigene families for rDNA. The number of clusters for 45S gene ranged from one to three pairs, with exclusively location in autosomes, except for Carollia perspicillata that had in X chromosome. The 5S gene all the species studied had only one site located on an autosomal pair. In no species the 45S and 5S genes collocated. The fluorescence in situ hybridization (FISH) probe for telomeric sequences revealed fluorescence on all telomeres in all species, except in Carollia perspicillata. Non-telomeric sites in the pericentromeric region of the chromosomes were observed in most species, ranged from one to 12 pairs. Most interstitial telomeric sequences were coincident with heterochromatic regions. The results obtained in the present work indicate that different evolutionary mechanisms are acting in Phyllostomidae genome architecture, as well as the occurrence of Robertsonian fusion during the chromosomal evolution of bats without a loss of telomeric sequences. These data contribute to understanding the organization of multigene families and telomeric sequences on bat genome as well as the chromosomal evolutionary history of Phyllostomidae bats. 相似文献
72.
Introduction
Health care utilization is an important step to disease management, providing opportunities for prevention and treatment. Anderson’s Health Behavior Model has defined utilization by need, predisposing, and enabling determinants. We hypothesize that need, predisposing, and enabling, highlighting behavioral factors are associated with utilization in Argentina.Methods
We performed a logistic regression analysis of the 2005 and 2009 Argentinean Survey of Risk Factors, a cohort of 41,392 and 34,732 individuals, to explore the association between need, enabling, predisposing, and behavioral factors to blood pressure measurement in the last year.Results
In the 2005 cohort, blood pressure measurement was associated with perception of health, insurance coverage, basic needs met, and income. Additionally, female sex, civil state, household type, older age groups, education, and alcohol use were associated with utilization. The 2009 cohort showed similar associations with only minor differences between the models.Conclusions
We explored the association between utilization of clinical preventive services with need, enabling, predisposing, and behavioral factors. While predisposing and need determinants are associated with utilization, enabling factors such as insurance coverage provides an area for public intervention. These are important findings where policies should be focused to improve utilization of preventive services in Argentina. 相似文献73.
Roman Schumann Stephanie B. Jones Vilma E. Ortiz Kathleen Connor Istvan Pulai Edwin T. Ozawa Alan M. Harvey Daniel B. Carr 《Obesity (Silver Spring, Md.)》2005,13(2):254-266
Objective: To develop evidence‐based recommendations that optimize the safety and efficacy of perioperative anesthetic care and pain management in weight loss surgery (WLS) patients. Research Methods and Procedures: This Task Group examined the scientific literature on anesthetic perioperative care and pain management published in MEDLINE from January 1994 to March 2004. We also reviewed additional data from other sources (e.g., book chapters). The search yielded 195 abstracts, of which 35 references were reviewed in detail. Task Group consensus was used to provide recommendations when evidence in the literature was insufficient. Results: We developed anesthesia practice and patient safety advisory recommendations for preoperative evaluation, intraoperative management, and postoperative care and pain management of WLS patients. We also provided suggestions related to medical error reduction and systems improvements, credentialing, and future research. Discussion: Obesity‐related comorbidities including obstructive sleep apnea place WLS patients at increased risk for complications perioperatively. Regarding perioperative safety and outcomes, conclusive evidence beyond the accepted standard of care in the reviewed literature is limited. Few reports specifically address the perioperative needs of severely obese patients. In this advisory, we synthesize current knowledge and make best practice recommendations for perioperative care and pain management in WLS patients. These recommendations require periodic review as further medical knowledge and evidence evolve. 相似文献
74.
75.
Patrick J. Venta James A. Brouillette Vilma Yuzbasiyan-Gurkan George J. Brewer 《Biochemical genetics》1996,34(7-8):321-341
We are developing a genetic map of the dog based partly upon markers contained within known genes. In order to facilitate
the development of these markers, we have used polymerase chain reaction (PCR) primers designed to conserved regions of genes
that have been sequenced in at least two species. We have refined the method for designing primers to maximize the number
that produce successful amplifications across as many mammalian species as possible. We report the development of primer sets
for 11 loci in detail:CFTR, COL10A1, CSFIR, CYP1A1, DCN1, FES, GHR, GLB1, PKLR, PVALB, andRB1. We also report an additional 75 primer sets in the appendices. The PCR products were sequenced to show that the primers
amplify the expected canine genes. These primer sets thus define a class of gene-specific sequence-tagged sites (STSs). There
are a number of uses for these STSs, including the rapid development of various linkage tools and the rapid testing of genomic
and cDNA libraries for the presence of their corresponding genes. Six of the eleven gene targets reported in detail have been
proposed to serve as “anchored reference loci” for the development of mammalian genetic maps [O'Brien, S. J.,et al., Nat. Genet.
3:103, 1993]. The primer sets should cover a significant portion of the canine genome for the development of a linkage map.
In order to determine how useful these primer sets would be for the other genome projects, we tested the 11 primer sets on
the DNA from species representing five mammalian orders. Eighty-four percent of the gene-species combinations amplified successfully.
We have named these primer sets “universal mammalian sequence-tagged sites” because they should be useful for many mammalian
genome projects. 相似文献
76.
Antibacterial Effect of Cysteine-Nitrosothiol and Possible Percursors Thereof 总被引:9,自引:5,他引:4
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The postulated intermediate of nitrite-myoglobin reaction, cysteine-nitrosothiol, was prepared and its antibacterial effect was tested on Salmonella strains, Streptococcus faecium, and spores and vegetative cells of Clostridium sporogenes. Cysteine-nitrosothiol showed a higher inhibitory effect than nitrite. Preliminary results on the effect of simultaneous use of nitrite and cysteine on Clostridium sporogenes spores were also presented. 相似文献
77.
Four different chemical extraction procedures for the isolation of wheat germ agglutinin receptor sites from L1210 cells are described. Fractionation of the biologically active material on Sephadex G-200 columns in pyridine results in two major peaks, the lower molecular weight fraction having a higher inhibitory activity. Electrophoresis in polyacrylamide sodium dodecyl sulfate gels yields four bands. The most active fraction from Sephadex G-200 has an approximate molecular weight between 40000–60000. A preliminary analysis of the active material indicates the presence of sialic acid, neutral sugars and amino sugars, including N-acetylglucosamine. 相似文献
78.
Leticia S. Guidolin Vilma Arce‐Gorvel Andrés E. Ciocchini Diego J. Comerci Jean‐Pierre Gorvel 《Cellular microbiology》2018,20(6)
Cyclic β‐1,2‐D‐glucans (CβG) are natural bionanopolymers present in the periplasmic space of many Proteobacteria. These molecules are sugar rings made of 17 to 25 D‐glucose units linked exclusively by β‐1,2‐glycosidic bonds. CβG are important for environmental sensing and osmoadaptation in bacteria, but most importantly, they play key roles in complex host–cell interactions such as symbiosis, pathogenesis, and immunomodulation. In the last years, the identification and characterisation of the enzymes involved in the synthesis of CβG allowed to know in detail the steps necessary for the formation of these sugar rings. Due to its peculiar structure, CβG can complex large hydrophobic molecules, a feature possibly related to its function in the interaction with the host. The capabilities of the CβG to function as molecular boxes and to solubilise hydrophobic compounds are attractive for application in the development of drugs, in food industry, nanotechnology, and chemistry. More importantly, its excellent immunomodulatory properties led to the proposal of CβG as a new class of adjuvants for vaccine development. 相似文献
79.
Nicoletta Rascio Paola Mariani Vilma Perin Francesca Dalla Vecchia Paola Castaldo 《Plant biology (Stuttgart, Germany)》1997,110(3):224-233
An ultrastructural study on the reserves stored in cotyledons and endosperm and on their utilization after germination has been carried out in Cercis siliquastrum seeds. The observations have shown that all the cotyledonal reserves of proteins and lipids are used during seedling growth. However, inside the endosperm cells only the protein reserves are depleted, and large quantities of lipids remain undigested. In both cell walls and intercellular spaces of the endosperm cells huge masses of polysaccharide reserves are stored. However, only the polysaccharides inserted in the cell walls are dismantled, while those located in the intercellular spaces are not attacked by the lytic enzymes. Some hypotheses regarding the possible roles of those endospermic non-nutritional materials in the strategies of seed germination and seedling growth are suggested. 相似文献
80.
Alterations of the cerebrospinal fluid (CSF) composition are useful clinical diagnostic tools as well as a source of candidates for new biomarkers of neurodegenerative disorders. This Editorial highlights a study by Rodrigues and colleagues in which the authors try to establish Tau as a new biomarker for Huntington´s disease (HD). The study confirmed in two independent, age‐controlled patient populations at various disease stages, asymptomatic mutation carriers and healthy controls, that CSF total Tau concentrations in HD gene mutation carriers are increased compared with healthy controls. This is a strong evidence that CSF total Tau concentration is associated with phenotypic variability in HD. Read the highlighted article ‘Cerebrospinal fluid total tau concentration predicts clinical phenotype in Huntington's disease’ on page 22 . 相似文献