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81.
In this work, Ba2MgWO6: Eu3+ (BMW: Eu3+) ceramic materials with a double perovskite structure were sintered using the High-Pressure Low-Temperature sintering (HPLT) technique. As part of the research, the influence of pressure (CP), sintering temperature (CT), and sintering time (CTS) on the structure and luminescence of the doped BMW were determined. Structural analysis via XRD and SEM + EDS and spectroscopic analysis via emission and excitation spectra, decay time, and absorption spectra of the obtained ceramics were performed. Dense double perovskite ceramics were obtained with a cubic structure with optimal sintering parameters: T = 500 °C, p = 8 GPa, and t = 1 min. The increase in temperature caused an increased extinction of the luminescence due to the diffusion of carbon into the ceramics. The increase in pressure led to the formation of the amorphous phase, which increased the speed of non-radiative transitions and also led to the extinction of the luminescence. The increase in sintering time from 1 to 3 min enhanced the luminescence output, but when the ceramic was sintered for 5 min, the luminescence was quenched, most likely by increasing the rate of the non-radiative process, as evidenced by reduced decay time.  相似文献   
82.
Background/AimsThis study aimed to determine changes in endoscopist-driven sedation practices 5 years after the first nationwide survey in 2014 by the Korean Society of Gastrointestinal Endoscopy (KSGE).MethodsA 59-item survey covering current practices was electronically mailed to all members of the KSGE in 2019.ResultsIn total, 955 (12.8%) out of 7,486 questionnaires were returned. A total of 738 (77.7%) out of 955 respondents attended dedicated sedation education programs. The American Society of Anesthesiologists class was recorded by 464 (51.2%) out of 907 respondents. The recording rate was higher in respondents who completed sedation education (p=0.014) and worked in general or tertiary hospitals (p<0.001). Compared to that reported in the previous survey, the reported use of propofol was higher in 2019. The respondents had higher satisfaction scores for propofol-based sedation compared with midazolam monotherapy (p<0.001). The rates of oxygen supplementation (p<0.001) and oxygen saturation level monitoring (p<0.001) during sedative endoscopy were higher in 2019 than in the previous survey. A total of 876 (98.4%) out of 890 respondents reported a separate recovery bay, and 615 (70.5%) out of 872 respondents reported that personnel were assigned solely to the recovery bay.ConclusionsEndoscopist-driven sedation and monitoring practices in 2019 were significantly different than those in 2014. The respondents favored propofol-based sedation and utilized oxygen supplementation and monitoring of O2 saturation more frequently in 2019 than in 2014. (Gut Liver, Published online August 1, 2022)  相似文献   
83.
A dietary pattern transition is a risk factor for the double burden of malnutrition (DBM), but related information is limited. This study aimed to identify sex differences in dietary patterns of adults in a low–middle income country and to examine their association with DBM. A total of 8957 adults (4465 men and 4492 non-pregnant and non-lactating women) who participated in the 2013 Philippine National Nutrition Survey were included in the analysis. Logistic regression models were formulated to investigate the relationship between dietary patterns and DBM. The factor analysis derived seven dietary patterns for males and six patterns for females. Results showed that approximately 30% of Filipino adults suffered from DBM. The rice pattern was associated with lower odds of DBM for males only. The meat and sugar pattern in males and the protein-rich foods, cereal, and sugar pattern in females decreased DBM likelihood. An inverse relationship was observed for the vegetables and corn patterns, wherein females had an increased risk for DBM. Our findings suggest that rice-based and meat-containing patterns could play protective roles in DBM development among adults in the Philippines. Understanding sex-specific dietary patterns can be utilized to guide public health nutrition interventions in the prevention of malnutrition in all its forms.  相似文献   
84.
Epigenetics is a series of alterations regulating gene expression without disrupting the DNA sequence of bases. These regulatory mechanisms can result in embryogenesis, cellular differentiation, X-chromosome inactivation, and DNA-protein interactions. The main epigenetic mechanisms considered to play a major role in both health and disease are DNA methylation, histone modifications, and profiling of non-coding RNA. When the fragile balance between these simultaneously occurring phenomena is disrupted, the risk of pathology increases. Thus, the factors that determine proper epigenetic modeling are defined and those with disruptive influence are sought. Several such factors with proven negative effects have already been described. Diet and nutritional substances have recently been one of the most interesting targets of exploration for epigenetic modeling in disease states, including autoimmunity. The preventive role of proper nutrition and maintaining sufficient vitamin D concentration in maternal blood during pregnancy, as well as in the early years of life, is emphasized. Opportunities are also being investigated for affecting the course of the disease by exploring nutriepigenetics. The authors aim to review the literature presenting vitamin D as one of the important nutrients potentially modeling the course of disease in selected autoimmune disorders.  相似文献   
85.
The relationship of high-carbohydrate (HC) meal intake to metabolic syndrome is still not fully explained. Metabolomics has the potential to indicate metabolic pathways altered by HC meals, which may improve our knowledge regarding the mechanisms by which HC meals may contribute to metabolic syndrome development. The fasting and postprandial metabolic response to HC or normo-carbohydrate (NC) meals with/without cinnamon + capsicum intake was evaluated using untargeted metabolomics and compared between normal-weight (NW) and overweight/obese (OW/OB) healthy men. Healthy male participants (age-matched) were divided into two groups (12 subjects per group). One was composed of men with normal weight (NW) and the other of men with overweight/obesity (OW/OB). On separate visits (with 2–3 week intervals), the participants received standardized HC or NC meals (89% or 45% carbohydrates, respectively). Fasting (0 min) and postprandial (30, 60, 120, 180 min) blood were collected for untargeted plasma metabolomics. Based on each metabolic feature’s intensity change in time, the area under the curve (AUC) was calculated. Obtained AUCs were analyzed using multivariate statistics. Several metabolic pathways were found dysregulated after an HC meal in people from the OW/OB group but not the NW group. The consumption of HC meals by people with overweight/obesity led to a substantial increase in AUC, mainly for metabolites belonging to phospholipids and fatty acid amides. The opposite was observed for selected sphingolipids. The intake of cinnamon and capsicum normalized the concentration of selected altered metabolites induced by the intake of HC meals. A HC meal may induce an unfavourable postprandial metabolic response in individuals with overweight/obesity, and such persons should avoid HC meals.  相似文献   
86.
1-取代吡唑烷酮类抗惊构效关系的研究   总被引:5,自引:0,他引:5  
1-正癸基吡唑烷-3-酮(Ⅱ结构式见表1)是欧洲专利报道的一种新型减肥剂。White等报道该化合物可通过血脑屏障,并对γ-氨基丁酸氨基转移酶(GABA-T)有强烈的抑制活性,但对谷氨酸脱羧酶的抑制作用较弱,因此可引起脑内γ-氨基丁酸(GABA)水平的升高,故我们相信应有抗惊活性。经我们合成后,发现Ⅱ确有良好的抗癲痫活性,抗小鼠最大电  相似文献   
87.
High mobility group box 1 (HMGB1) mediates proinflammatory responses in inflammatory diseases. Lycopene found in tomatoes and tomato products has anti-oxidant, anti-cancer and antiinflammatory effects. The potential anti-inflammatory roles of lycopene in HMGB1-mediated proinflammatory responses in both primary human umbilical vein endothelial cells (HUVECs) and animal were investigated. The anti-inflammatory effects of lycopene were determined including permeability, monocyte adhesion and migration, and activation of proinflammatory proteins and HMGB1 receptors on HMGB1 activated HUVECs. In the in vivo model, the anti-inflammatory effect of lycopene was assessed by monitoring vascular permeability and migration of leukocytes to the peritoneal cavity of mice injected with lycopene. Lycopene inhibited lipopolysaccharide (LPS)-mediated release of HMGB1, expression of HMGB1-mediated tumor necrosis factor (TNF)-secretory phospholipase A2 (sPLA2)-IIA, and HMGB1-mediated pro-inflammatory signaling responses in endothelial cells. It did this through down-regulation of cell surface expression of cell adhesion molecules (CAMs), HMGB1 receptors, toll-like receptor (TLR)-2, and -4, and receptors for advanced glycation end products (RAGE). These findings suggest that lycopene promotes barrier integrity, inhibits monocyte adhesion and migration to HMGB1 activating HUVECs by blocking activation of proinflammatory cytokines and expression of CAMs and HMGB1 receptors, thereby showing its usefulness as a therapy for vascular inflammatory diseases.  相似文献   
88.
慢性痛或神经痛是一种临床综合征,常伴有抑郁障碍,严重影响患者生活质量.对于神经痛,常规镇痛药物、甚至麻醉性镇痛药经常无效,而抗抑郁药、抗精神病药和抗癫痫药物等则有效.本文综述了抗抑郁药用于镇痛的作用机制和不同类型的抗抑郁药在疼痛治疗中的应用,旨在为疼痛的临床治疗提供参考.  相似文献   
89.
CGS 15435A, a novel thromboxane (Tx) synthetase inhibitor (5-chloro-1-methyl-2-(3-pyridyl)-3-indolhexanoic acid HCl), had a selectivity for Tx synthetase 100,000-fold greater than that for cyclooxygenase, PGI2 synthetase and lipoxygenase enzymes. In conscious beagles, 1 h following a single 3 mg/kg p.o. dose, serum TxB2 was inhibited 95% by CGS 15435 and 82% by dazoxiben (DAZ). Unlike the short acting Tx synthetase inhibitor DAZ, CGS 15435A significantly inhibited TxB2 formation 4, 6, 12 and 24 h after dosing. Serum levels of 6-keto PGF1 alpha and PGE2 were significantly increased following the administration of either drug. CGS 15435A and DAZ were further examined in a model with known Tx involvement. Thrombotic sudden death, produced in anesthetized rabbits by injection of 0.75 mg/kg arachidonic acid (AA) i.v. resulted in a 45% fall in the platelet count and 0% survival. Pretreatment with DAZ (8.6 mumol/kg i.v.) at 0.25 or 2 h pre-AA resulted in 3 and 42% thrombocytopenia and 100 and 0% survival respectively. CGS 15435A (8.6 mumol/kg i.v.) prevented the increases in plasma TxB2 levels, thrombocytopenia and sudden death with pretreatment at 0.25 h (0% thrombocytopenia and 100% survival) or 24 h (11% thrombocytopenia and 83% survival) before AA. These data indicate that CGS 15435A is a potent and selective Tx synthetase inhibitor with a long duration of action, and suggest that the compound could be useful in chronic, non-symptomatic indications of Tx involvement.  相似文献   
90.
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