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排序方式: 共有169条查询结果,搜索用时 18 毫秒
1.
Osorio Ana C. P. de Sena Rodrigo C. Araújo Thiago de O. de Almeida Marcelo D. 《Accreditation and quality assurance》2019,24(5):387-394
Accreditation and Quality Assurance - The production of Certified Reference Materials (CRMs) is one of the essential activities of the National Institute of Metrology, Quality and Technology... 相似文献
2.
Effectiveness of Photodynamic Therapy in Elimination of HPV‐16 and HPV‐18 Associated with CIN I in Mexican Women 下载免费PDF全文
Elizabeth Maldonado Alvarado Martha Olivia Osorio Peralta Alejandra Moreno Vázquez Lydia Alejandra Martínez Guzmán Maria Eugenia Melo Petrone Zulma Iveth Enriquez Mar Dora Estela Jovel Galdamez Bárbara Carrión Solana Guadalupe Balderas Martínez Eduarda Parra Rossana Inés Castellanos Oliveros Rosa Linda Bello Leiva Araceli Espinosa Montesinos Citlalli Barrera Mendoza Selma Eugenia Medina García Eva Ramón Gallegos 《Photochemistry and photobiology》2017,93(5):1269-1275
This study aimed to determine the effectiveness of photodynamic therapy (PDT), using δ‐aminolevulinic acid (5‐ALA), in the elimination of premalignant cervical lesions in Mexican patients with human papillomavirus (HPV) infection and/or cervical intraepithelial neoplasia (CIN). Thirty women diagnosed with CIN I and/or positive for HPV participated in the study. Topical 6% 5‐ALA in gel form was applied to the uterine cervix; after 4 h, the lesion area was irradiated with a light dose of 200 J cm?2 at 635 nm. This procedure was performed three times at 48‐h intervals. Clinical follow‐up was performed at 3, 6, and 12 months after the initial PDT administration, by colposcopy, cervical cytology, histopathological analysis, polymerase chain reaction, and hybrid capture. Of HPV‐infected patients without evidence of CIN I, 80% cleared the infection, while HPV associated with CIN I was eliminated in 83% of patients (P < 0.05). At 12 months, CIN I had regressed in 57% of patients, although this response was not statistically significant. PDT using 6% 5‐ALA is concluded to be effective in eliminating HPV infection associated or not with CIN I. 相似文献
3.
M. Duque‐Bernal J. D. Quintero‐Arias W. Osorio‐Viana I. Dobrosz‐Gómez J. Fontalvo M. Á. Gómez‐García 《国际化学动力学杂志》2013,45(1):10-18
The liquid‐phase esterification of acetic acid and isoamyl alcohol has been studied to develop a kinetic model using a sequential experimental design based on the divergence criterion. Data come from batch reactor experiments, performed in the temperature range of 316–363 K. Discrimination among 36 possible kinetic models, written in terms of activity, mole fractions, and molar densities, is possible through the deviance information criterion, as estimated by a Markov chain Monte Carlo technique. The obtained results indicate a negligible heat of reaction and a clear autocatalytic effect of acetic acid on the esterification rate. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 45: 10–18, 2013 相似文献
4.
5.
Edison Liang 《High Energy Density Physics》2013,9(3):425-427
Ultra-intense laser irradiating high-Z solid targets has become a new, powerful and efficient tool to create electron–positron pairs and intense gamma-ray beams. This paper reviews the recent developments in this field, both in theory and experiments. We will also discuss potential astrophysical applications of such laboratory experiments using ultra-intense lasers. 相似文献
6.
Lizbet Le��n Angel Bustamante Ana Osorio G. S. Olarte Luis De Los Santos Valladares Crispin H. W. Barnes Yutaka Majima 《Hyperfine Interactions》2011,202(1-3):131-137
In this work we report the preparation of magnetic hematite hollow sub-micron spheres (??-Fe2O3) by colloidal suspensions of ferric nitrate nine-hydrate (Fe(NO3)3·9H2O) particles in citric acid solution by following the sol?Cgel method. After the gel formation, the samples were annealed at different temperatures in an oxidizing atmosphere. Annealing at 180°C resulted in an amorphous phase, without iron oxide formation. Annealing at 250°C resulted in coexisting phases of hematite, maghemite and magnetite, whereas at 400°C, only hematite and maghemite were found. Pure hematite hollow sub-micron spheres with porous shells were formed after annealing at 600°C. The characterization was performed by X-ray diffraction (XRD), Mössbauer spectroscopy (MS) and scanning electron microscopy (SEM). 相似文献
7.
A. Amuthavalli D. Edison B. Prakash M. S. Sivaramkumar R. Velmurgan 《Crystallography Reports》2017,62(7):1066-1070
The title compound, C13H12BrNO, was synthesized and characterised by IR, 1H and 13C NMR spectroscopy. The proposed structure was confirmed by single crystal X-ray diffraction. The single crystal data revealed that the compound crystallizes in the triclinic system, sp. gr. P1, with Z = 2. The sevenmembered ring exhibits a slightly distorted envelope conformation. N–H···O hydrogen bonds form a centrosymmetric dimer, these interactions create a stair-like chain of molecules that interacts only loosely with neighbouring chains via van der Waals interactions, and C–H···π contacts are found in the crystal structure. 相似文献
8.
L. C. Sánchez A. M. Calle J. D. Arboleda J. J. Beltran C. A. Barrero J. Osorio K. Nomura 《Hyperfine Interactions》2008,183(1-3):117-122
The effect of different milling conditions on the formation of Fe-doped TiO2 powders by mechanical alloying was investigated by Mössbauer spectrometry. The milling conditions investigated were ball to powder weight ratio, milling time, rotation velocity of supporting disc, and the type of starting reactive iron and its concentration. X-ray diffraction shows that high energy mechanical milling of undoped anatase TiO2 induce the anatase to rutile phase transformation via high pressure srilankite. Mössbauer spectra for the majority of the doped samples were decomposed into one sextet and one or two doublets. The sextets was attributed to the presence of α-Fe or hematite impurities. The doublets were assigned to Fe3?+? incorporated in the TiO2 structure, and to the Fe2?+? located either at the surface or the interstitial sites of TiO2. A greater incorporation of Fe in the TiO2 structure was observed when samples were prepared from hematite instead of α-Fe. 相似文献
9.
The dynamics of a point-like relativistic particle with respect of the proper time is formulated on the hyperboloid p
2
0–p
2=M
2
c
2. The Hamilton-Jacobi equations on the hyperboloid are derived for the particles with mass (M
2=m
2, m>0), for the particles with zero-mass (M=0, m>0), and for the neutrino. It is shown, in a certain factorization of the momentum, the model can be identified with Nambu's three-dimensional phase space formalism. A first quantized version of the model is formulated according to a canonical scheme of quantization (Schrödinger quantization scheme). 相似文献
10.
Henry Insuasty Braulio Insuasty Edison Castro Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(9):908-911
In the title compound, C15H12N4OS2, the bond distances in the fused heterocyclic system show evidence for aromatic‐type delocalization in the pyrazole ring with some bond fixation in the triazine ring. The thiophenyl substituent is slightly disordered over two sets of atomic sites having occupancies of 0.934 (4) and 0.066 (4). The non‐H atoms in the entire molecule are nearly coplanar, with the planes of the furanyl substituent and the major orientation of the thiophenyl substituent making dihedral angles of 5.72 (17) and 1.8 (3)°, respectively, with that of the fused ring system. Molecules are linked into centrosymmetric R22(10) dimers by C—H...O hydrogen bonds and these dimers are further linked into chains by a single π–π stacking interaction. Comparisons are made with some related 4,7‐diaryl‐2‐(ethylsulfanyl)pyrazolo[1,5‐a][1,3,5]triazines which contain variously substituted aryl groups in place of the furanyl and thiophenyl substituents in the title compound. 相似文献