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71.
Rui Pereira Christopher Phillips Cíntia Alves António Amorim Ángel Carracedo Leonor Gusmão 《Electrophoresis》2009,30(21):3682-3690
Human identification is usually based on the study of STRs or SNPs depending on the particular characteristics of the investigation. However, other types of genetic variation such as insertion/deletion polymorphisms (indels) have considerable potential in the field of identification, since they can combine the desirable characteristics of both STRs and SNPs. In this study, a set of 38 non‐coding bi‐allelic autosomal indels reported to be polymorphic in African, European, and Asian populations were selected. We developed a sensitive genotyping assay, which is able to characterize all 38 bi‐allelic markers using a single multiplex PCR and detected with standard CE analyzers. Amplicon length was designed to be shorter than 160 bp. Complete profiles were obtained using 0.3 ng of DNA, and full genotyping of degraded samples was possible in cases where standard STR typing had partially failed. A total of 306 individuals from Angola, Mozambique, Portugal, Macau, and Taiwan were studied and population data are presented. All indels were polymorphic in the three population groups studied and the random match probabilities of the set ranged in orders of magnitude from 10?14 to 10?15. Therefore, the indel‐plex represents a valuable approach in human identification studies, especially in challenging DNA cases, as a more straightforward and efficient alternative to SNP typing. 相似文献
72.
Rodrigo S. Muceneeki Clarissa M. Amorim Talita G. Cesca Maique W. Biavatti Tania M. B. Bresolin 《Chromatographia》2009,69(Z2):219-223
The Mikania genus is widely known as guaco and is used to treat fever, rheumatism, influenza and respiratory diseases. This article deals
with the simultaneous quantification of three commercially available phenolic markers (o-coumaric acid, coumarin and syringaldehyde) in M. laevigata extracts, through LC-PDA. The validation data show that the method is specific, accurate, precise and robust, and also indicative
of the stability of guaco extract. The method was linear, over a range of 1.25–20.0 μg mL−1 for o-coumaric acid, 2.5–40.0 μg mL−1 for coumarin, and 0.25–4.0 μg mL−1 for syringaldehyde. The range of recovery was 94.3–96.4% for all the components, at a level of 100%. 相似文献
73.
Lucas Andreo Carla A. Soldera Beatriz Guimares Ribeiro Patrick Raoul Vicente de Matos Paola Bindes Sousa Weslley Wallace de Alcntara Araújo Amorim Anna Carolina Ratto Tempestini Horliana Sandra Kalil Bussadori Kristianne Porta Santos Fernandes Raquel Agnelli Mesquita‐Ferrari 《Photochemistry and photobiology》2019,95(3):879-885
A peripheral nerve injury (PNI) can result in motor or sensory disorders. Low‐level laser therapy (LLLT) has demonstrated positive results as a treatment option for PNI. Wistar rats were divided into five groups: Control, Injury, Injury + LLLTn (nerve), Injury + LLLTm (muscle) and Injury + LLLTn + m (nerve and muscle irradiation). The groups were analyzed after one, two, three and four weeks. PNI was achieved by crushing the sciatic nerve. Laser treatment (780 nm, 3.2 J) was realized over the nerve and/or tibialis anterior muscle. In gait analyses, the groups irradiated over the nerve demonstrated an improvement after two weeks. In the analysis of mechanical sensitivity, the Injury + LLLTn demonstrated a reduction after one week in comparison with Injury group; the Injury + LLLTn + m and Injury + LLLTm demonstrated an increase after two weeks in comparison with Injury group; and the irradiated groups demonstrated a reduction in nociception after four weeks in comparison with Injury group. In the analysis of muscle atrophy, the Injury + LLLTn demonstrated more muscle mass after two weeks. LLLT improves functional aspects related to gait, mechanical sensitivity and muscle mass, with better results regarding motor aspects and muscle mass when administered over the injured nerve and better results regarding sensory aspects when administered over the muscle. 相似文献
74.
Cruz-Filho J. S. Amorim R. G. G. Khanna F. C. Santana A. E. Santos A. F. Ulhoa S. C. 《International Journal of Theoretical Physics》2019,58(10):3203-3224
The Seiberg-Witten formalism has been realized as an electrodynamics in phase space (associated to the Dirac equation written in phase space) and this fact is explored here with non-abelian gauge group. First, a physically heuristic presentation of the Seiberg-Witten approach is carried out for non-abelian gauge in order to guide the calculation procedures. These results are realized by starting with the Lagrangian density for the free Dirac field in phase space. Then a field strength is derived, where the non-abelian gauge group is the SU(2), corresponding to an isospin (non-abelian) field theory in phase space. An application to nucleon is then discussed.
相似文献75.
Quantum mechanical molecular dynamics shows that gold nanowires formed along the [110] direction reconstruct upon stress to form helical nanowires. The mechanism for this formation is discussed. These helical nanowires evolve on stretching to form linear atomic chains. Because helical nanowires do not form symmetrical tips, a requirement to stop the growth of atomic chains, these nanowires produce longer atomic chains than other nanowires. These results are obtained resorting to the use of tight-binding molecular dynamics and ab initio electronic structure calculations. 相似文献
76.
77.
Ricardo Amorim 《General Relativity and Gravitation》1985,17(6):525-533
A consistent set of equations of motion for classical charged particles with spin and magnetic dipole moment in a Riemann-Cartan space-time is generated from a constrained Lagrangian formalism. The equations avoid the spurious free helicoidal solutions and at the same time conserve the canonical condition of normalization of the 4-velocity. The 4-velocity and the mechanical moment are parallel in this theory, where the condition of orthogonality between spin and 4-velocity is treated as a nonholonomic constraint. A generalized BMT precession equation is obtained as one of the results of the formalism. 相似文献
78.
79.
Lima CS De Amorim EL Nascimento SC De Araújo CF Agra MF Barbosa-Filho JM Silva MS Da-Cunha EV Vieira IJ Braz-Filho R 《Natural product research》2005,19(3):217-222
Three new pyranonaphthoquinones: 5-hydroxy-6-methoxy-alpha-lapachone, 5,6-dihydroxy-a-lapachone and 4',5-dihydroxy-6-methoxy-alpha-lapachone, and two known compounds: lapachol and 5,5'-dihydroxy-3',4',7-trimethoxyflavanone, were isolated from the stem bark of Melloa quadrivalvis. Their structures were established by spectrometric data, mainly 1D- and 2D-NMR and mass spectra. The methylazoetetrazolium (MTT) method using viable cells of the strain Hep2 and the strain NCIH-292 demonstrated cytotoxic activity. The CI50 was also calculated. The chloroform extract and 5-hydroxy-6-methoxy-alpha-lapachone inhibited cell growth. 相似文献
80.
E. A. N. Fernandes N. Nepomuceno A. B. Trevizam H. V. Amorim 《Journal of Radioanalytical and Nuclear Chemistry》1998,236(1-2):113-119
A chemical and radiochemical neutron activation analysis (CNAA/RNAA) method has been developed for the determination of three
calcium isotopes (48Ca,46Ca, and44Ca) in a single sample derived from urine. This method was developed in support of clinical research using a dual enriched
stable isotope methodology to study bone mineralization in premature infants, juvenile rheumatoid arthritics, and cystic fibrosis.
In these studies, one enriched isotope of calcium is administered orally, and one is administered intravenously. By making
determinations of three isotopes (two enriched, one unenriched) within the same sample, the perturbation from natural isotopic
ratios can be determined and used to calculate true absorption of calcium. In our method,48Ca is determined via the48Ca(n,γ)49Ca reaction and 3084 keV gamma-ray,46Ca via the46Ca(n,γ)47Ca reaction and 1296 keV gamma-ray, and44Ca via the44Ca(n,γ)45Ca reaction and 256 keV (max) beta-particle. A pair of chemical separation steps are employed to separate calcium from urine
as calcium oxalate with a yield in the range of 80–90%, and a radiochemical step is employed prior to the measurement of45Ca to remove interfering radionuclides. 相似文献