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111.
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
112.
Linda Doyle 《Tetrahedron》2010,66(34):7041-2138
Thermal reactions of C-aryl δ-alkenyl oximes give N-unsubstituted bicylic lactone, lactam and pyrrolidine fused isoxazolidines by an intramolecular oxime olefin cycloaddition pathway (IOOC) and/or cyclic nitrones by an azaprotio cyclotransfer (APT) route; a number of factors, including the nature of the aryl group, the oxime geometry and the structure of the linker between the oxime and the terminal alkene, contribute to the competition. 相似文献
113.
Achim Edtbauer Stephan Denifl Dr. Violaine Vizcaino Dr. Lukas An der Lan Katherine Russell Jörg Taubitz Dr. Uta Wille Dr. Linda Feketeova Dr. Richard A. J. O'Hair Prof. Dr. Tilmann D. Märk Prof. Dr. Eugen Illenberger Prof. Dr. Paul Scheier Prof. Dr. 《Chemphyschem》2010,11(3):561-564
Electrons with virtually no kinetic energy (close to 0 eV) trigger the decomposition of cytotoxic cyclobutane‐pyrimidine dimer (CPD) into a surprisingly large variety of fragment ions plus their neutral counterparts. The response of CPD to low energy electrons is thus comparable to that of explosives like trinitrotoluene (TNT). The dominant unimolecular reaction is the splitting into two thymine like units, which can be considered as the essential molecular step in the photolyase of CPD. We find that CPD is significantly more sensitive towards low energy electrons than its thymine building blocks. It is proposed that electron attachment at very low energy proceeds via dipole bound states, supported by the large dipole moment of the molecule (6.2 D). These states act as effective doorways to dissociative electron attachment (DEA). 相似文献
114.
Linda Schweda 《Journal of organometallic chemistry》2010,695(18):2076-2082
The reaction of α,β-unsaturated imines with [(1,5-cyclooctadiene)-bis(2-methylallyl)-ruthenium(II)] leads to the formation of mononuclear ruthenium complexes of the general formula {(COD)Ru[RNC(H)-C(H)C(Ph)]2}. In these complexes the imine ligands are deprotonated in β-position with respect to the imine double bond and coordinate as an enyl-imino ligand. In the case of R = Me, Et the corresponding compounds have been characterized by X-ray crystallography. The relevance of these complexes with respect to ruthenium catalyzed C-C coupling reactions of the same α,β-unsaturated imines is demonstrated by the structural analysis of another mononuclear ruthenium complex in which two imine ligands are reductively coupled (R = Cy). [(1,5-Cyclooctadiene)-bis(2-methylallyl)-ruthenium(II)] also turns out to be a highly effective precatalyst in the reaction of the respective imines with carbon monoxide and ethylene to produce heterocyclic compounds. 相似文献
115.
Jun Zhang Ramona Rodila Eric Gage Mathew Hautman Leimin Fan Linda L. King Huaiqin Wu Tawakol A. El-Shourbagy 《Analytica chimica acta》2010,661(2):167-172
Simvastatin (SS) is an effective cholesterol-lowering medicine, and is hydrolyzed to simvastatin acid (SSA) after oral administration. Due to SS and SSA inter-conversion and its pH and temperature dependence, SS and SSA quantitation is analytically challenging. Here we report a high-throughput salting-out assisted liquid/liquid extraction (SALLE) method with acetonitrile and mass spectrometry compatible salts for simultaneous LC-MS/MS analysis of SS and SSA. The sample preparation of a 96-well plate using SALLE was completed within 20 min, and the SALLE extract was diluted and injected into an LC-MS/MS system with a cycle time of 2.0 min/sample. The seamless interface of SALLE and LC-MS eliminated drying down step and thus potential sample exposure to room or higher temperature. The stability of SS and SSA in various concentration ratios in plasma was evaluated at room and low (4 °C) temperature and the low temperature (4 °C) was found necessary to maintain sample integrity. The short sample preparation time along with controlled temperature (2-4 °C) and acidity (pH 4.5) throughout sample preparation minimized the conversion of SS → SSA to ≤0.10% and the conversion of SSA → SS to 0.00% The method was validated with a lower limit of quantitation (LLOQ) of 0.094 ng mL−1 for both SS and SSA and a sample volume of 100 μL. The method was used for a bioequivalence study with 4048 samples. Incurred sample reproducibility (ISR) analysis of 362 samples from the study exceeded ISR requirement with 99% re-analysis results within 100 ± 20% of the original analysis results. 相似文献
116.
The purpose of this article is to examine the effects of five univariate scoring techniques for rank order categorical data and the results of analyses using each of the techniques for five‐ and ten‐point bi‐polar adjective scales. The effect of scoring method and scale length is assessed for the resultant distance to multivariate normality, inter‐item reliability, discriminant analysis, least squares regression and logistic regression. For these data, the strongest effect of scoring was on distance to multivariate normality and determination of significant variables. 相似文献
117.
118.
Dr. Ana M. Ortuño Dr. Pablo Reiné Prof. Luis Álvarez de Cienfuegos Dr. Irene R. Márquez Dr. Wynand Dednam Prof. Enrico B. Lombardi Prof. Juan J. Palacios Dr. Edmund Leary Prof. Giovanna Longhi Prof. Vladimiro Mujica Dra. Alba Millán Dra. M. Teresa González Linda A. Zotti Dra. Delia Miguel Prof. Juan M. Cuerva 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218640
We report on the chemical design of chiral molecular junctions with stress-dependent conductance, whose helicity is maintained during the stretching of a single molecule junction due to the stapling of both ends of the inner helix. In the reported compounds, different conductive pathways are observed, with clearly different conductance values and plateau-length distributions, attributed to different conformations of the helical structures. The large chiro-optical responses and the potential use of these molecules as unimolecular spin filters have been theoretically proved using state-of-the-art Density Functional Theory (DFT) calculations, including a fully ab-initio estimation of the CISS-originating spin polarization which is done, for the first time, for a realistic molecular system. 相似文献
119.
Linda Lesmak 《Discrete Mathematics》1976,14(2):165-169
A graph G of order p ? 3 is called n-hamiltonian, 0 ? n ? p ? 3, if the removal of any m vertices, 0 ? m ? n, results in a hamiltonian graph. A graph G of order p ? 3 is defined to be n-hamiltonian, ?p ? n ? 1, if there exists ?n or fewer pairwise disjoint paths in G which collectively span G. Various conditions in terms of n and the degrees of the vertices of a graph are shown to be sufficient for the graph to be n-hamiltonian for all possible values of n. It is also shown that if G is a graph of order p ? 3 and , then G is n-hamiltonian. 相似文献
120.
Görbitz CH Nilsen M Szeto K Tangen LW 《Chemical communications (Cambridge, England)》2005,(34):4288-4290
Cocrystallized acetonitrile solvent molecules located inside 5.2 A channels in the crystal structure of L-leucyl-L-serine have been replaced by I2 molecules with full retention of the peptide scaffold. 相似文献