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排序方式: 共有747条查询结果,搜索用时 31 毫秒
1.
Umar Nadia K. Badshah Maaz B. Sandrasegaran Kumar Ghabril Marwan Agarwal Saurabh Tann Mark Lacerda Marco Kwo Paul Y. 《Digestive diseases and sciences》2015,60(7):2196-2200
Digestive Diseases and Sciences - To determine whether the presence of portal vein thrombosis (PVT) where venous flow within the liver may be altered may delay the diagnosis of HCC and be... 相似文献
2.
Raul Quijada Jairton Dupont Mrcia S. Lacerda Miranda Rosngela B. Scipioni Griselda B. Galland 《Macromolecular chemistry and physics.》1995,196(12):3991-4000
The behaviour of catalytic systems based on zirconium compounds for the copolymerization of ethylene with 1-hexene and 1-octene is reported. The metallocenes (CH3)2SiCp2ZrCl2, Cp2ZrCl2 (Cp = η5-cyclopentadienyl), C2H4[Ind]2ZrCl2 and (Ind = η5-indenyl) were chosen for this study. The bridged catalysts, (CH3)2SiCp2ZrCl2 and C2H4[Ind]2ZrCl2, and the metallocene Cp2ZrCl2 showed similar catalytic activities for home- and copolymerization of ethylene with 1-hexene. 13C NMR analysis showed that the composition of copolymerization products depends on the catalytic system, in other words, on the ligand structure of the transition metal. Copolymers obtained using the bridged catalysts have greater incorporation of comonomer. Thermal analysis and viscosity measurements demonstrated that an increase of the comonomer concentration reduces the melting point, the crystallinity and the molecular weight of the copolymer. Results from infrared spectroscopy showed that β-elimination is one of the possible termination reactions. The monomer reactivity ratios r were determined for all catalytic systems using Fineman-Ross and 13C NMR methods. The values of r1 (M1 = ethylene) and r2 (M2 = α-olefin) showed an effect of the type of metallocene and of α-olefin on the structure of the copolymer obtained. 相似文献
3.
M C Dauge V Delmas C A Mandarim de Lacerda 《Bulletin de l'Association des anatomistes》1986,70(211):5-11
The initial prostatic development was investigated here with morphometric methods. Five male human fetuses, ranging in crown-rump length from 50 to 92 mm (foetal age 9 to 12.5 weeks) were studied. The morphometric analysis underline the importance of the prostatic mesenchyme and the later growth of the epithelial buds. Some reconstructions showed a crescent-shaped disposition of the supra-deferentials buds, according to the actual hypothesis about a "preprostatic" zone. 相似文献
4.
5.
A number of neurotoxins from venoms of invertebrates and plants are ligands for voltage-gated Na+ channels and are useful tools for studying Na+ channel function and structure. Using whole-cell recordings from vagal afferent nodose neurons, we studied neurotoxins that target Na+ channels. We asked whether Ts3 (an α-scorpion toxin) and/or veratridine (a lipid-soluble toxin), could modify the TTX-resistant Na+ current generated by vagal afferent nodose neurons. Nodose TTX-resistant current was not affected by Ts3, whereas Ts3 slowed inactivation of the current generated by TTX-sensitive current component. We found that veratridine inhibited the TTX-resistant Na+ currents on rat nodose neurons. Interestingly, veratridine-modified Na+ channels developed a persistent current that accounted for the large tail current observed. We propose that veratridine modifies TTX-resistant Na+ channels through a mechanism distinct from its actions on other voltage-gated Na+ channels. 相似文献
6.
P. Monteiro D.B. Miranda-Filho F. Bandeira H.R. Lacerda H. Chaves M.F.P.M. Albuquerque U.R. Montarroyos R.A.A. Ximenes 《Brazilian journal of medical and biological research》2012,45(9):818-826
We investigated the association between pulse wave velocity (PWV) and HIV infection, antiretroviral treatment-related characteristics, viral load, immune status, and metabolic changes in a cross-sectional study nested in a cohort of HIV/AIDS patients who have been followed for metabolic and cardiovascular changes since 2007. The study included patients recruited from the cohort (N = 261) and a comparison group (N = 82) of uninfected individuals, all enrolled from April to November 2009. Aortic stiffness was estimated using the carotid-femoral PWV (Complior-Artech, Paris, France). The groups were similar with respect to age, metabolic syndrome, diabetes mellitus, Framingham score, and use of antihypertensive and hypolipidemic medications. Hypertension was more frequent among the controls. Individuals with HIV had higher triglyceride, glucose and HDL cholesterol levels. Among individuals with HIV/AIDS, those with a nadir CD4+ T-cell count <200 cells/mm3 had a higher PWV (P = 0.01). There was no statistically significant difference when subjects were stratified by gender. Heart rate, age, male gender, and blood pressure were independently correlated with PWV. Nadir CD4+ T-cell count did not remain in the final model. There was no significance difference in PWV between HIV-infected individuals and uninfected controls. PWV was correlated with age, gender, and blood pressure across the entire population and among those infected with HIV. We recommend cohort studies to further explore the association between inflammation related to HIV infection and/or immune reconstitution and antiretroviral use and PWV. 相似文献
7.
Joanna d'Arc Lyra Batista Maria de Fátima Pessoa Milit?o de Albuquerque Marcela Lopes Santos Demócrito de Barros Miranda-Filho Heloísa Ramos Lacerda Magda Maruza Libia Vilela Moura Isabella Coimbra Ricardo Arraes de Alencar Ximenes 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(2):127-132
Despite the effectiveness of combination antiretroviral therapy in the
treatment of people living with HIV/AIDS (PLWHA), nonadherence to medication has
become a major threat to its effectiveness. This study aimed to estimate the
prevalence of self-reported irregular use of antiretroviral therapy and the factors
associated with such an irregularity in PLWHA. A cross-sectional study of PLWHA who
attended two referral centers in the city of Recife, in Northeastern Brazil, between
June 2007 and October 2009 was carried out. The study analyzed socioeconomic factors,
social service support and personal habits associated with nonadherence to
antiretroviral therapy, adjusted by multivariable logistic regression analysis. The
prevalence of PLWHA who reported irregular use of combination antiretroviral therapy
(cART) was 25.7%. In the final multivariate model, the irregular use of cART was
associated with the following variables: being aged less than 40 years (OR =
1.66, 95%-CI: 1.29-2.13), current smokers (OR = 1.76, 95%-CI: 1.31-2.37) or
former smokers (OR = 1.43, 95%-CI: 1.05-1.95), and crack cocaine users (OR
= 2.79, 95%-CI: 1.24-6.32). Special measures should be directed towards each
of the following groups: individuals aged less than 40 years, smokers, former smokers
and crack cocaine users. Measures for giving up smoking and crack cocaine should be
incorporated into HIV-control programs in order to promote greater adherence to
antiretroviral drugs and thus improve the quality of life and prolong life
expectancy. 相似文献
8.
9.
DNA methylation patterns of genes related to immune response in the different clinical forms of oral lichen planus
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Aline Fernanda Cruz Renata Gonçalves de Resende Júlio César Tanos de Lacerda Núbia Braga Pereira Leonardo Augusto Melo Marina Gonçalves Diniz Carolina Cavalieri Gomes Ricardo Santiago Gomez 《Journal of oral pathology & medicine》2018,47(1):91-95
Background
The oral lichen planus is a chronic inflammatory disease. Although its aetiology is not well understood, the role of T lymphocytes in its inflammatory events is recognised. Identifying the epigenetic mechanisms involved in the pathogenesis of this immune‐mediated condition is fundamental for understanding the inflammatory reaction that occurs in the disease. The purpose of this work was to evaluate the methylation pattern of 21 immune response‐related genes in the different clinical forms of oral lichen planus.Methods
A cross‐sectional study was performed to analyse the DNA methylation patterns in three distinct groups of oral lichen planus: (i) reticular/plaque lesions; (ii) erosive lesions; (iii) normal oral mucosa (control group). After DNA extraction from biopsies, the samples were submitted to digestions by methylation‐sensitive and methylation‐dependent enzymes and double digestion. The relative percentage of methylated DNA for each gene was provided using real‐time polymerase chain reaction arrays.Results
Hypermethylation of the STAT5A gene was observed only in the control group (59.0%). A higher hypermethylation of the ELANE gene was found in reticular/plaque lesions (72.1%) compared to the erosive lesions (50.0%).Conclusion
Our results show variations in the methylation profile of immune response‐related genes, according to the clinical type of oral lichen planus after comparing with the normal oral mucosa. Further studies are necessary to validate these findings using gene expression analysis. 相似文献10.