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141.
Vascular aging, characterized by structural and functional alterations of the vascular wall, is a hallmark of aging and is tightly related to the development of cardiovascular mortality and age-associated vascular pathologies. Over the last years, extensive and ongoing research has highlighted several sophisticated molecular mechanisms that are involved in the pathophysiology of vascular aging. A more thorough understanding of these mechanisms could help to provide a new insight into the complex biology of this non-reversible vascular process and direct future interventions to improve longevity. In this review, we discuss the role of the most important molecular pathways involved in vascular ageing including oxidative stress, vascular inflammation, extracellular matrix metalloproteinases activity, epigenetic regulation, telomere shortening, senescence and autophagy.  相似文献   
142.
The Tigris hydropower system is analyzed through an integrated operational policy. The operation algorithm is formulated in terms of non-linear programming to maximize energy production while satisfying water demands in the basin. The system is optimized for different cases, and the effects of system modifications in terms of the reservoir volume of Ilisu Dam and the demand constraints are examined. In addition, the state of the Garzan subsystem is analyzed to explore plant utilization when optimizing the entire system operations. The results show the necessity of such an integrated operation plan to supply water demands in the basin.  相似文献   
143.
We investigated plasma sphingomyelin (CerPCho) and ceramide (Cer) levels in pediatric patients with cystic fibrosis (CF) and primary ciliary dyskinesia (PCD). Plasma samples were obtained from CF (n = 19) and PCD (n = 7) patients at exacerbation, discharge, and stable periods. Healthy children (n = 17) of similar age served as control. Levels of 16–24 CerPCho and 16–24 Cer were measured by LC–MS/MS. Concentrations of all CerPCho and Cer species measured at exacerbation were significantly lower in patients with CF than PCD. 16, 18, 24 CerPCho, and 22, 24 Cer in exacerbation; 18, 24 CerPCho, and 18, 20, 22, 24 Cer at discharge; 18, 24 CerPCho and 24 Cer at stable period were significantly lower in CF patients than healthy children (p < 0.001 and p < 0.05). All CerPCho and Cer levels of PCD patients were significantly higher except 24 CerPCho and 24 Cer during exacerbation, 24 CerPCho at discharge, and 18, 22 CerPCho levels at stable period (p < 0.001 and p < 0.05) compared with healthy children. There was no significant difference among exacerbation, discharge, and stable periods in each group for Cer and CerPCho levels. This is the first study measuring plasma Cer and CerPCho levels in PCD and third study in CF patients. The dramatic difference in plasma levels of most CerPCho and Cer species found between two diseases suggest that cilia pathology in PCD and CFTR mutation in CF seem to alter sphingolipid metabolism possibly in opposite directions.  相似文献   
144.
AFMC-AIMECS meetings are internationally organized biannually by the Asian Federation for Medicinal Chemistry (AFMC) and are focused on recent studies in drug discovery and development both in academia and industry. Member organizations of the AFMC are the Pharmaceutical Society of Japan, the Chinese Pharmaceutical Association, the Royal Australian Chemical Institute, the Pharmaceutical Society of Korea, the Korean Chemical Society, the Chemical Society Located in Taipei, the Indonesian Society of Medicinal Chemistry, the Medicinal Chemistry Section of the Israel Chemical Society, and the Computer-Aided Drug Design & Development Society in Turkey. Each time, the symposium is organized within these member countries. The AIMECS 2019 symposium was held in Turkey this year, as Prof. Dr. Esin Aki-Yalcin is the current president of the AFMC (2018–2020); the next AIMECS meeting will be organized in 2021 in Tokyo, Japan. In this report, we discuss key topics at the 12th AFMC International Medicinal Chemistry Symposium — New Avenues for Design and Development of Translational Medicine (AIMECS 2019) held in Istanbul, September 8–11, 2019.  相似文献   
145.
146.
Abstract

In this study, the effects of air nozzles called jetring or nozzlering, on yarn quality which is used as an additional process in conventional ring spinning machines have been investigated. The response surface methodology (RSM) was used to investigate the yarn properties value. In the experiment, Ne30/1 100% cotton fibers were used. In all jetring yarn productions, the air pressure was kept at 125?kPa (gauge). In all samples, the nozzle length was kept 27?mm and twisting chamber diameter was kept Ø2mm. The number of injectors has been kept constant as 4 pieces. Giving the best yarn quality as a result of RSM, injector diameter Ø0.5?mm and injector angle 35° as determined. With this nozzle structural configuration, yarn hairiness values were reduced by 9.2% but yarn irregularity values were increased by 0.7%, yarn elongation values were decreased by 6.2% and yarn tenacity (cN/tex) values decreased to 5.6.  相似文献   
147.
Magnetic Resonance Materials in Physics, Biology and Medicine - Both fibroadenomas (FAs) and phyllodes tumors (PTs) are classified as fibroepithelial lesions. PTs are rare fibroepithelial neoplasms...  相似文献   
148.
It is anticipated that oxidized low‐density lipoprotein (oxLDL) and anti‐oxLDL are associated with atherosclerosis and mortality. However, data on this issue are controversial and limited. We aimed to investigate the effect of these two markers on the extent and progression of atherosclerosis and mortality in a group of hemodialysis patients. In this prospective observational study with a follow‐up of 36 months, 124 hemodialysis patients were studied. Ninety‐five patients underwent carotid intima media thickness (CA‐IMT) measurement by B‐Mode ultrasonography both at baseline and at the end of the study. oxLDL and anti‐oxLDL were measured by enzyme‐linked immunosorbent assay. The extent and progression of CA‐IMT, along with overall and cardiovascular mortality, were assessed. The mean age at baseline was 54.0 ± 14.8 years, 57.3% male and 20% diabetic. The mean oxLDL and anti‐oxLDL levels were 8.11 ± 3.16 mU/L and 1.30 ± 0.31, respectively. Baseline mean CA‐IMT was 0.82 ± 0.20 mm. Fifteen patients died during a follow‐up period of 28.5 ± 6.6 months, 11 from cardiovascular causes. Only oxLDL, not anti‐oxLDL, was correlated with the extent of atherosclerosis at baseline. However, both had no role in the progression of atherosclerosis. Also, in unadjusted and adjusted models, both parameters were not associated with overall or cardiovascular mortality. Neither oxLDL nor anti‐oxLDL level is associated with the progression of atherosclerosis or mortality in hemodialysis patients.  相似文献   
149.
Health-related quality of life (HRQoL) and sleep quality (SQ) were impaired in patients with end-stage renal disease (ESRD). The impairment of both HRQoL and SQ and being in a depressive mood were found to be associated with increased morbidity and mortality in dialysis patients. We aimed to investigate the association between SQ, HRQoL, and depression, and to define independent predictors of SQ and depression in peritoneal dialysis (PD) and hemodialysis (HD) patients. Ninety HD patients (41 females, 49 males with mean age 50 ± 15.7 years) and 64 PD patients (27 females, 37 males with mean age 52.4 ± 15.3 years) receiving renal replacement therapy for at least 3 months were screened for the assessment of SQ, HRQoL, and depression in this cross-sectional study. A modified postsleep inventory, Short Form of Medical Outcomes Study (SF-36) and Beck depression inventory (BDI) were applied to all patients for evaluating SQ, HRQoL, and depression, respectively. HD and PD patients had similar total SQ scores. Physical and mental component scale of HRQoL were found to be significantly higher in HD patients (p < 0.001). PD patients were found to be much more in depressive mood when compared with HD patients (p < 0.001). Independent predictors of depression in patients were mental component scale of HRQoL, gender (being female), and dialysis modality (being PD patient). Physical component scale was also found to be an independent predictor of SQ. This study showed that despite similar SQ scores between two groups, HD patients had better HRQoL and less depression than PD patients.  相似文献   
150.
Bi1?x Sb x nanoparticles were prepared by mechanical alloying and compacted using different techniques. The influence of the composition as well as the pressing conditions on the thermoelectric performance was investigated. A strong dependence of the thermoelectric properties on the composition was found, which deviates from the behavior of single crystals. The results indicate a significant change in the band structure of the material induced by the reduced size. The influence of the pressing conditions on the thermoelectric properties also showed composition dependence. The results show that the compacting method has to be chosen carefully.  相似文献   
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