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11.
Quality of Life Research - Examining the associations of a-posteriori-defined dietary patterns and health-related quality of life (HRQOL) among Iranian adolescents. This cross-sectional study was...  相似文献   
12.
Testicular torsion is a dangerous urogenital disorder which is caused by twisting of spermatic cord, and unless immediate treatments happen at a proper time, oxidative stress, occurred during ischaemia reperfusion, finally leads to irreversible disintegration of testicular tissue. One of the first preventive lines is to administrate antioxidant factors. In the present study, we investigate the therapeutic effect of cerium oxide nanoparticle on the injury. We divided 45 rats into nine groups, subjected eight groups to testicular torsion–detorsion, injected different doses of cerium oxide nanoparticle into the peritoneum of six groups and analysed all the groups regarding spermatogenetic indices including sperm count, sperm viability and Johnson mean. Our results showed that cerium oxide nanoparticle can alleviate oxidative stress in testis, and this alleviation promotes the reproductive indices as the concentration of cerium oxide nanoparticles increases. The catalase-mimetic and superoxide dismutase-mimetic activities of cerium oxide nanoparticle are the most probable theories to explain the antioxidant effect of the nanoparticle.  相似文献   
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In this study, natural convection flow in a porous cavity with sinusoidal temperature distribution has been analyzed by a new double multi relaxation time (MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9 lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9 have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement with the previous works, thus confirming the reliability the new numerical method proposed in this paper. It is indicated that the heat transfer rate increases at increasing Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and phase deviation. However, the most sensitive parameter is the Rayleigh number. The maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on the heat transfer rate increases at increasing Rayleigh number, yielding a maximum enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and Ra=$10^5$, respectively.  相似文献   
15.
Portilla-Fernández  Eliana  Hwang  Shih-Jen  Wilson  Rory  Maddock  Jane  Hill  W. David  Teumer  Alexander  Mishra  Pashupati P.  Brody  Jennifer A.  Joehanes  Roby  Ligthart  Symen  Ghanbari  Mohsen  Kavousi  Maryam  Roks  Anton J. M.  Danser  A. H. Jan  Levy  Daniel  Peters  Annette  Ghasemi  Sahar  Schminke  Ulf  Dörr  Marcus  Grabe  Hans J.  Lehtimäki  Terho  Kähönen  Mika  Hurme  Mikko A.  Bartz  Traci M.  Sotoodehnia  Nona  Bis  Joshua C.  Thiery  Joachim  Koenig  Wolfgang  Ong  Ken K.  Bell  Jordana T.  Meisinger  Christine  Wardlaw  Joanna M.  Starr  John M.  Seissler  Jochen  Then  Cornelia  Rathmann  Wolfgang  Ikram  M. Arfan  Psaty  Bruce M.  Raitakari  Olli T.  Völzke  Henry  Deary  Ian J.  Wong  Andrew  Waldenberger  Melanie  O’Donnell  Christopher J.  Dehghan  Abbas 《European journal of epidemiology》2021,36(11):1143-1155

Common carotid intima-media thickness (cIMT) is an index of subclinical atherosclerosis that is associated with ischemic stroke and coronary artery disease (CAD). We undertook a cross-sectional epigenome-wide association study (EWAS) of measures of cIMT in 6400 individuals. Mendelian randomization analysis was applied to investigate the potential causal role of DNA methylation in the link between atherosclerotic cardiovascular risk factors and cIMT or clinical cardiovascular disease. The CpG site cg05575921 was associated with cIMT (beta?=??0.0264, p value?=?3.5?×?10–8) in the discovery panel and was replicated in replication panel (beta?=??0.07, p value?=?0.005). This CpG is located at chr5:81649347 in the intron 3 of the aryl hydrocarbon receptor repressor gene (AHRR). Our results indicate that DNA methylation at cg05575921 might be in the pathway between smoking, cIMT and stroke. Moreover, in a region-based analysis, 34 differentially methylated regions (DMRs) were identified of which a DMR upstream of ALOX12 showed the strongest association with cIMT (p value?=?1.4?×?10–13). In conclusion, our study suggests that DNA methylation may play a role in the link between cardiovascular risk factors, cIMT and clinical cardiovascular disease.

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16.
The1H-NMR signals of 2-cephems and 3-cephems have been assigned and the Nuclear Overhauser Effect (NOE) study of these compounds was undertaken.  相似文献   
17.
An investigation was undertaken to determine the toxicity of an intravitreal injection of a novel peptide drug, Shiva-1, in rabbits. The drug, a synthetic peptide modeled after lytic peptides secreted by certain insects, has antiproliferative and antibacterial properties. Initial in vitro experiments showed that the drug, at a concentration of 100 M, was toxic to both Y-79 retinoblastoma cells and human retinal pigment epithelial cells. A wide range of doses (6–1200 g) was injected into the rabbit vitreous in an attempt to determine the maximum tolerated dose. Retinal toxicity was evaluated clinically, by electroretinography, and by light microscopy. Some localized toxicity was evident at 200 g; all doses of 240 g and above were toxic. While the drug appears to exhibit a narrow range between effective and toxic doses, the results suggest that this and other peptides of similar design merit further investigation for the treatment of proliferative and infectious diseases of the eye.Supported in part by U.S. Public Health Service grants EY07541 and EY02377 from the National Eye Institute, the National Institutes of Health Services, Bethesda, MD, USA  相似文献   
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Any task is carried out more successfully if we allocate undivided attention to it, but as demands on attentional capacity increase-for example, in concurrent or dual task conditions-performance on attended tasks becomes more impaired. Patients with schizophrenia show impaired performance on tasks requiring high levels of attentional capacity. This study examines performance of 11 patients with schizophrenia and 13 normal controls on two motor tasks (placing pegs in a pegboard and repetitive index finger tapping) under unimanual, bimanual, and dual task conditions. The patients with schizophrenia placed fewer pegs and had reduced tapping speed in unimanual and bimanual conditions. However, the decrement in bimanual performance as a percentage of unimanual performance was not significantly different for the patients and controls on either the pegboard or tapping tasks. By contrast, under dual task conditions, the performance of the patients with schizophrenia in peg placement actually improved relative to the unimanual pegboard task, whereas tapping performance deteriorated compared with the unimanual tapping, a decrement that was significantly greater for the patients. Thus the improvement in the visually guided pegboard task was at the expense of the repetitive tapping task. These results are discussed in terms of an impairment of self initiated movement with general sparing of externally triggered movements in schizophrenia and the role of frontostriatal loops in this process.  相似文献   
20.
The S1-S2 go/no-go reaction time task has been frequently used to assess volitional inhibition. In this study our aim was to compare the ERPs elicited by S1 and S2 by using a modified S1-S2 paradigm which involved a two-stage go/no-go decision. The go and the no-go S1 ERPs did not differ substantially, and both displayed a prominent negativity with peaks at 260 ms (S1N260) and at 330 ms (S1N330) post-S1. The S1N260 was similar to the N2 from no-go S2 trials. Since after all three types of stimuli, movement is not required and is inappropriate, this negativity may represent the correlate of the voluntary decision to suppress movement. Later, the S1 ERPs were dominated by frontal negativity (S1N330), probably reflecting further processes related to response preparation, while the S2 ERPs displayed a large central and parietal positivity (P3), probably reflecting the processes of evaluation of response accuracy.  相似文献   
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