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排序方式: 共有1725条查询结果,搜索用时 15 毫秒
131.
Sueva Cantalupo Vito Alessandro Lasorsa Roberta Russo Immacolata Andolfo Giuseppe DAlterio Barbara Eleni Rosato Giulia Frisso Pasquale Abete Gian Marco Cassese Giuseppe Servillo Ivan Gentile Carmelo Piscopo Matteo Della Monica Giuseppe Fiorentino Giuseppe Russo Pellegrino Cerino Carlo Buonerba Biancamaria Pierri Massimo Zollo Achille Iolascon Mario Capasso 《International journal of molecular sciences》2021,22(10)
Genome-wide association studies (GWAS) found locus 3p21.31 associated with severe COVID-19. CCR5 resides at the same locus and, given its known biological role in other infection diseases, we investigated if common noncoding and rare coding variants, affecting CCR5, can predispose to severe COVID-19. We combined single nucleotide polymorphisms (SNPs) that met the suggestive significance level (P ≤ 1 × 10−5) at the 3p21.31 locus in public GWAS datasets (6406 COVID-19 hospitalized patients and 902,088 controls) with gene expression data from 208 lung tissues, Hi-C, and Chip-seq data. Through whole exome sequencing (WES), we explored rare coding variants in 147 severe COVID-19 patients. We identified three SNPs (rs9845542, rs12639314, and rs35951367) associated with severe COVID-19 whose risk alleles correlated with low CCR5 expression in lung tissues. The rs35951367 resided in a CTFC binding site that interacts with CCR5 gene in lung tissues and was confirmed to be associated with severe COVID-19 in two independent datasets. We also identified a rare coding variant (rs34418657) associated with the risk of developing severe COVID-19. Our results suggest a biological role of CCR5 in the progression of COVID-19 as common and rare genetic variants can increase the risk of developing severe COVID-19 by affecting the functions of CCR5. 相似文献
132.
DeSteno David; Bartlett Monica Y.; Braverman Julia; Salovey Peter 《Canadian Metallurgical Quarterly》2002,83(5):1103
Two studies are presented that challenge the evidentiary basis for the existence of evolved sex differences in jealousy. In opposition to the evolutionary view, Study 1 demonstrated that a sex difference in jealousy resulting from sexual versus emotional infidelity is observed only when judgments are recorded using a forced-choice response format. On all other measures, no sex differences were found, both men and women reported greater jealousy in response to sexual infidelity. A second study revealed that the sex difference on the forced-choice measure disappeared under conditions of cognitive constraint. These findings suggest that the sex difference used to support the evolutionary view of jealousy likely represents a measurement artifact resulting from a format-induced effortful decision strategy and not an automatic, sex-specific response shaped by evolution. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
133.
Chiara Bignardi Monica Mattarozzi Andrea Penna Simone Sidoli Lisa Elviri Maria Careri Alessandro Mangia 《Food Analytical Methods》2013,6(4):1144-1152
Enhanced sensitivity for the simultaneous determination of five nut allergens in biscuit and in dark chocolate complex matrices was obtained by introduction of a rapid size-exclusion solid-phase extraction-based step before liquid chromatography–electrospray ionization-tandem mass spectrometry (LC-ESI-MS2) analysis. A very fast and efficient separation (<12 min) of marker peptides with selected reaction monitoring detection was obtained. Limits of detection in the 0.1–1.3 mg nut/kg and 5–15 mg nut/kg ranges for biscuit and dark chocolate samples as well as high recoveries (84(±6)–106(±4)% for biscuits and 98(±5)–108(±6)% for dark chocolate) proved the excellent capabilities of the exploited sample treatment method combined with the LC-MS2 analysis. Good precision in terms of intra- and inter-day repeatability was calculated, being always lower than 19 % (n?=?75). Linearity was demonstrated up to four and three orders of magnitude for biscuit and dark chocolate, respectively. Finally, the validated method was successfully applied to the investigation of hidden nut trace allergens in commercially available biscuits and chocolates of different brands aiming to ascertain possible discrepancies between allergen content and food allergen labelling. 相似文献
134.
Roberto Rosa Paolo Veronesi Shahoua Han Valentina Casalegno Milena Salvo Elena Colombini Cristina Leonelli Monica Ferraris 《Journal of the European Ceramic Society》2013,33(10):1707-1719
Microwaves at 2.45 GHz have been applied to ignite the combustion synthesis of compacted Ti–Si–C powders mixtures, having 1:1:1 atomic ratio, in order to join SiC-based components. A mixture of different refractory phases such as TiC and TiSi2 were obtained. Depending on the synthesis conditions, no residual silicon in the joint was detected, suggesting the suitability of the here proposed experimental joining approach for nuclear plants and high temperature applications. A simplified model was developed with the aim of obtaining a deeper understanding of the here proposed rapid, almost pressure-less and localized heating joining method. Experimental and numerical simulation results demonstrate that joining of SiC can be rapidly obtained with minimization of heat affected zones in the SiC substrates. Maximum apparent shear strength values of the joints ranged from 9.9 to 45.1 MPa, depending on the process conditions. 相似文献
135.
One goal of the VaNTH Engineering Research Center is to estimate the effects of the “value added” to bioengineering student learning as a result of “How People Learn” (HPL) framework interventions. A necessary step in that process is to assess pedagogical differences in both lecture‐based and HPL‐oriented courses. Data from 28 bioengineering courses, over five semesters, were analyzed using a newly developed HPL Index. This index, developed from the Classroom Interaction Observation portion of the VaNTH Observation System, reports levels of HPL‐inspired pedagogy, traditional pedagogy, and classroom organization within a class using codes for different types of faculty and student interactions assigned by an observer in real time. Results confirm the HPL Index's ability to distinguish pedagogical practices based on HPL principles and pedagogical practices based on traditional, non‐HPL pedagogy. 相似文献
136.
Sergio R. Idelsohn Monica Mier-Torrecilla Norberto Nigro Eugenio Oñate 《Computational Mechanics》2010,46(1):115-124
Heterogeneous incompressible fluid flows with jumps in the viscous properties are solved with the particle finite element
method using continuous and discontinuous pressure fields. We show the importance of using discontinuous pressure fields to
avoid errors in the incompressibility condition near the interface. 相似文献
137.
Ageing in men is accompanied by a progressive decline of gonadal function with, in particular, a decline of total and free testosterone (T) plasma levels resulting in a significant proportion of elderly men over age 60 years presenting with subnormal T levels compared with the levels in young adults. A great interindividual variation in T levels is observed in elderly men, a variability explained in part by physiological variables and differences in life style, while associated acute or chronic diseases may accentuate the age-related decline of T levels. The progressive decrease of plasma T levels has been shown to result from both primary testicular changes and altered neuroendocrine regulation of Leydig cell function. At present, little is known about the clinical relevance of the relative hypoandrogenism of elderly men and there is an urgent need for more longitudinal studies, which may clarify a possible role of decreased T levels in the modulation of the clinical consequences of ageing in men. In view of the lack of relevant controlled clinical trials having careful assessment of the risks and benefits of androgen replacement therapy in elderly men, this treatment should be reserved for selected patients with clinically and biochemically manifest hypogonadism, after careful screening for contraindications. 相似文献
138.
J. Nijs S. Sivoththaman J. Szlufcik K. De Clercq F. Duerinckx E. Van Kerschaever R. Einhaus J. Poortmans Tom Vermeulen R. Mertens 《Solar Energy Materials & Solar Cells》1997,48(1-4)
Fabrication technologies for multicrystalline silicon (mc-Si) solar cells have advanced in recent years with efficiencies of mc-Si cells exceeding 18%. Intense efforts have been made at laboratory level to improve process technology, growth methods, and material improvement techniques to deliver better devices at lower cost. Deeper understanding of the physics and optics of the device led to improved device design. This provided a fruitful feedback to the industrial sector. Both screenprinting and buried-contact technologies yield cells of high performance. An increasingly large amount of research activity is also focussed on the fabrication of thin solar cells on cheap substrates such as glass, ceramic, or low quality silicon. Success of these efforts is expected to lead to high efficiency devices at much lower costs. Efforts are also being put on low thermal budget processing of solar cells based on rapid thermal annealing. 相似文献
139.
Piero De Filippis Monica Boscolo Mario Gibellini Paolo Rupena Fulvio Rubessa 《Drug development and industrial pharmacy》1991,17(14):2017-2028
The coprecipitates were prepared by a solvent technique using Eudragit E as carrier and indomethacin as a model drug.
X-Ray diffractometry, differential scanning calorimetry (DSC) and wettability tests were employed to investigate the physical state of the studied formulations. Up to 50% of indomethacin can be dispersed in an amorphous state in Eudragit E.
The influence of the pH on the in vitro release of solid dispersions has been evaluated. Because of the good solubility of Eudragit E at pH 1.2 a fast dissolution rate of the drug was observed while a marked delay was noticed at pH 7.5 where the polymer is only permeable to water. At pH 5.8 the kinetics of drug release can be modulated by the drug/polymer ratio. The dissolution rate of the drug can be increased by decreasing its amount in the coevaporate. 相似文献
X-Ray diffractometry, differential scanning calorimetry (DSC) and wettability tests were employed to investigate the physical state of the studied formulations. Up to 50% of indomethacin can be dispersed in an amorphous state in Eudragit E.
The influence of the pH on the in vitro release of solid dispersions has been evaluated. Because of the good solubility of Eudragit E at pH 1.2 a fast dissolution rate of the drug was observed while a marked delay was noticed at pH 7.5 where the polymer is only permeable to water. At pH 5.8 the kinetics of drug release can be modulated by the drug/polymer ratio. The dissolution rate of the drug can be increased by decreasing its amount in the coevaporate. 相似文献
140.
Ellinger D.C. Chute F.S. Vermeulen F.E. 《IEEE transactions on bio-medical engineering》1989,36(10):987-994
A modified solenoid having a semi-circular cross section is evaluated as an applicator for radio-frequency heating of biological materials. The operating efficiency of this applicator and the distribution of the electric field established within a simulated biological sample are determined for a number of modes of excitation. It is shown that uniform heating to a substantial depth is possible at efficiencies in excess of 80 percent. 相似文献