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2.
Julieta Ramos-Loyo Andrés Antonio Gonzalez-Garrido Claudia Amezcua Miguel A Guevara 《International journal of psychophysiology》2004,54(3):251-262
In spite of previous reports on the relationship between ongoing EEG and ERPs, there remains a lack of agreement on the nature of their nexuses. The aim of the present study was to evaluate the relationship between resting EEG and the ERP components in two groups of healthy subjects with different levels of performance in a highly demanding selective visual attention task. Young adults were classified according to the amount of their correct responses in the task, into high (HP; averaged hits (AH): 86%) and low performance groups (LP; AH: 59%). EEG was recorded during rest, prior to task performance and absolute (AP) and relative power (RP), as well as inter- (rTER) and intrahemispheric (rTRA) correlation were calculated. ERPs during task performance were also obtained and their amplitude and latency measures were assessed. Results showed that individuals with better behavioral performance had a higher synchronization between both hemispheres during rest as well as higher amplitude and shorter latencies of N2 and P3. Principal Component Analysis revealed that alpha2 AP and RP were inversely related to P2 and N2 latency. Higher values of alpha1 and alpha2 rTER were clustered with higher P3 amplitude and shorter reaction time. In conclusion, the differences in the cortical organization of HP and LP at rest (EEG) seem to be associated to the way the brain reacts during information processing (ERPs). 相似文献
3.
Steven D. Herman Paul D. Radecki Arnold C. Friedman Dina F. Caroline Parvati Ramchandani Louis M. Marmon Julieta D. Grosh 《Urologic radiology》1988,9(1):225-227
Sonography detected a paraaortic pulsatile tubular mass in a patient 10 years after “stump” nephrectomy, which was subsequently confirmed as a renal artery-renal vein fistula by computed tomography, angiography, and laparotomy. 相似文献
4.
In vitro and in vivo characterization of a Bordetella bronchiseptica mutant strain with a deep rough lipopolysaccharide structure
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Sisti F Fernández J Rodríguez ME Lagares A Guiso N Hozbor DF 《Infection and immunity》2002,70(4):1791-1798
Bordetella bronchiseptica is closely related to Bordetella pertussis, which produces respiratory disease primarily in mammals other than humans. However, its importance as a human pathogen is being increasingly recognized. Although a large amount of research on Bordetella has been generated regarding protein virulence factors, the participation of the surface lipopolysaccharide (LPS) during B. bronchiseptica infection is less understood. To get a better insight into this matter, we constructed and characterized the behavior of an LPS mutant with the deepest possible rough phenotype. We generated the defective mutant B. bronchiseptica LP39 on the waaC gene, which codes for a heptosyl transferase involved in the biosynthesis of the core region of the LPS molecule. Although in B. bronchiseptica LP39 the production of the principal virulence determinants adenylate cyclase-hemolysin, filamentous hemagglutinin, and pertactin persisted, the quantity of the two latter factors was diminished, with the levels of pertactin being the most greatly affected. Furthermore, the LPS of B. bronchiseptica LP39 did not react with sera obtained from mice that had been infected with the parental strain, indicating that this defective LPS is immunologically different from the wild-type LPS. In vivo experiments demonstrated that the ability to colonize the respiratory tract is reduced in the mutant, being effectively cleared from lungs within 5 days, whereas the parental strain survived at least for 30 days. In vitro experiments have demonstrated that, although B. bronchiseptica LP39 was impaired for adhesion to human epithelial cells, it is still able to survive within the host cells as efficiently as the parental strain. These results seem to indicate that the deep rough form of B. bronchiseptica LPS cannot represent a dominant phenotype at the first stage of colonization. Since isolates with deep rough LPS phenotype have already been obtained from human B. bronchiseptica chronic infections, the possibility that this phenotype arises as a consequence of selection pressure within the host at a late stage of the infection process is discussed. 相似文献
5.
Ming-Bo Liu Geraldine Dufour Zhuo-Er Sun Julieta Galante Chen-Qi Xing Jing-Ye Zhan Li-Li Wu 《中华创伤杂志(英文版)》2021,24(4):231-236
Purpose: As COVID-19 spreads globally and affects people''s health, there are concerns that the pandemic and control policies may have psychological effects on young people (age from 17 to 35 years). This psychological impact might vary in different countries, and thus we compared the prevalence of selfreported psychological distress, loneliness and posttraumatic stress symptoms (PTSS) among young people in the United Kingdom (UK) and China at the beginning of the COVID-19 pandemic.
Methods: Data of this study came from two sources. One source was the first wave of COVID-19 study in Understanding Society, a special wave of the UK household longitudinal study, which provided the highquality, national-wide representative panel data. The sample comprised 1054 young people. The other source was an online survey on the mental health of 1003 young people from Shanghai, a highly developed area in China. The questionnaire included questions on the prevalence of common mental disorders (cut-off score ≥ 4), loneliness and potential PTSS (cut-off ≥ 33). Univariable analyses were conducted to test the differences in the self-reported prevalence of psychological distress and loneliness between the two groups. Multivariable logistic regression analyses were run to explore the predictors of psychological distress and loneliness among all the young people from England and Shanghai.
Results: Among the samples with self-reported psychological distress, the UK sample accounted for 34.4% (n = 1054) and the Chinese sample accounted for 14.1% (n = 1003). The difference between the two groups was statistically significant (p < 0.001). Additionally, 57.1% of people in the UK and 46.7% in China reported that they sometimes or often felt lonely, of which the difference is statistically significant (p < 0.001). Regression analysis of the entire samples showed that nationality, gender, psychotherapy and loneliness were significant predictors of 12-item General Health Questionnaire scores, while the variables of age and living alone were not. Significant predictors of self-reported loneliness were the nationality, gender, age, living alone and psychotherapy. In China, 123 (12.3%) young people, 49 men (11.3%) and 74 women (13.0%), met the criteria of PTSS symptoms (cut-off scores ≥ 33). These scores were only collected in China.
Conclusion: This evidence suggests that mental health and loneliness reported by young people were lower in China than that in the UK during the studied period. More research is needed to understand these differences. If the differential negative psychological impacts are confirmed, country-specific measures of prevention and intervention should be adopted to improve the mental health of young people under the ongoing impact of the pandemic. 相似文献
6.
Freije MR 《Health facilities management》1990,3(10):28, 30, 32-28, 30, 34
7.
Beatrice-Adriana Serban Mihai-Tudor Olaru Ioana-Cristina Badea Dumitru Mitrica Marian Burada Ioana Anasiei Mihai Ghita Albert-Ioan Tudor Cristian-Alexandru Matei Ana Maria Julieta Popescu Virgil Constantin Florina Branzoi Cristian Dobrescu Nicolae Constantin 《Materials》2022,15(17)
Materials used in the marine industry are exposed to extreme conditions, so it is necessary to meet remarkable characteristics, such as mechanical resistance, low density, and good corrosion resistance. The challenging environment requires continuous performance improvements, so this work is focused on developing new materials with superior properties, using the electrochemical deposition technique, which are convenient for marine engineering. High-entropy alloys have been attracting tremendous interest in many applications, due to their simple crystal structures and advantageous physical-chemical properties, such as high strength, anti-corrosion, erosion, and electro-magnetic capabilities. To identify the most appropriate compositions, MatCalc software was used to predict the structure and characteristics of the required materials, and thermodynamic and kinetic criteria calculations were performed. The modelling processes generated a series of optimal compositions in the AlCrCuFeNi alloy system, that are suitable to be used in anticorrosive and tribological applications. The composition and morphology of the obtained high entropy alloy thin films revealed a uniform structure, with a small grain profile. The corrosion resistance was investigated in artificial seawater to observe the behavior of the newly developed materials in demanding conditions, and the results showed improved results compared to the copper foil substrate. 相似文献
8.
Mariana Fernndez-Lizrraga Julieta García-Lpez Sandra E. Rodil Rosa María Ribas-Aparicio Phaedra Silva-Bermudez 《Materials》2022,15(15)
Biomaterials with adequate properties to direct a biological response are essential for orthopedic and dental implants. The surface properties are responsible for the biological response; thus, coatings with biologically relevant properties such as osteoinduction are exciting options to tailor the surface of different bulk materials. Metal oxide coatings such as TiO2, ZrO2, Nb2O5 and Ta2O5 have been suggested as promising for orthopedic and dental implants. However, a comparative study among them is still missing to select the most promising for bone-growth-related applications. In this work, using magnetron sputtering, TiO2, ZrO2, Ta2O5, and Nb2O5 thin films were deposited on Si (100) substrates. The coatings were characterized by Optical Profilometry, Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, X-ray Photoelectron Spectroscopy, X-ray Diffraction, Water Contact Angle measurements, and Surface Free Energy calculations. The cell adhesion, viability, proliferation, and differentiation toward the osteoblastic phenotype of mesenchymal stem cells plated on the coatings were measured to define the biological response. Results confirmed that all coatings were biocompatible. However, a more significant number of cells and proliferative cells were observed on Nb2O5 and Ta2O5 compared to TiO2 and ZrO2. Nevertheless, Nb2O5 and Ta2O5 seemed to induce cell differentiation toward the osteoblastic phenotype in a longer cell culture time than TiO2 and ZrO2. 相似文献
9.
Scioscia Nathalia Paula Olmos Leandro Gorosábel Antonella Bernad Lucía Pedrana Julieta Denegri Guillermo María 《Parasitology research》2018,117(9):3023-3027
Parasitology Research - Lagochilascariosis is an emerging parasitic disease limited to the American continent, caused by nematodes of the genus Lagochilascaris. Its life cycle is heteroxenous,... 相似文献
10.
Subashini Onichandran Thulasi Kumar Yvonne A. L. Lim Nongyao Sawangjaroen Hemah Andiappan Cristina C. Salibay Tan Tian Chye Init Ithoi Julieta Z. Dungca Wan Y. W. Sulaiman Lau Yee Ling Veeranoot Nissapatorn 《Parasitology research》2013,112(12):4185-4191
The objective of this study was to assess the physico-chemical parameters and waterborne parasites in selected recreational lakes from Malaysia. Samples were collected from seven stations of Recreational Lake A (RL-A) and six stations of Recreational Lake B (RL-B). The samples were processed to detect the presence of Giardia spp. and Cryptosporidium spp. using immunomagnetic separation kit, helminth eggs or ova by bright field microscopy and Acanthamoeba spp. by cultivation in non-nutrient agar. Chemical parameters such as ammonia, chlorine, fluoride, nitrate and nitrite and physical parameters such as dissolved oxygen, electrical conductivity, pH, salinity, temperature and total dissolved solid were also measured. Both lakes were freshwater with salinity ranging from 0.05 to 0.09 ppt. Most stations of these lakes were contaminated with Cryptosporidium spp., Giardia spp., Ascaris spp. and hookworm. Schistosoma spp. was found in RL-B only, while Acanthamoeba spp. was found in all stations. Of all sampling sites, station 5 of RL-B is the most contaminated. Linear regression and correlation analysis revealed that Giardia spp. and Schistosoma spp. showed a significant negative correlation with turbidity (p?<?0.01). Based on the preliminary data obtained, it is clearly shown that there is a necessity to implement the detection of waterborne parasites and physico-chemical analysis in Malaysia. Future work on heavy metals (chromium, copper, mercury and zinc) is recommended to enhance the overall water quality monitoring and to take appropriate safety measures to ensure maintenance of good water standards. 相似文献