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Prospective study of the prevalence and co-morbidities of obstructive sleep apnea in active-duty army personnel in the three southernmost provinces of Thailand using questionnaire screening 被引量:3
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作者 Anisong Pilakasiri Prasit Mahakit 《Military Medical Research》 SCIE CAS CSCD 2019年第2期135-142,共8页
Background: It is crucial for the army to know the prevalence of obstructive sleep apnea(OSA) syndrome in activeduty army personnel. Little information has been reported on the prevalence of OSA and clinical features ... Background: It is crucial for the army to know the prevalence of obstructive sleep apnea(OSA) syndrome in activeduty army personnel. Little information has been reported on the prevalence of OSA and clinical features in activeduty army personnel. This study was aimed to estimate the prevalence of snoring and risk of developing OSA in activeduty army personnel in Thailand and to identify the co-morbidities of OSA. In total, 1107 participants who were aged20–60 years and were deployed to the three southernmost provinces of Thailand were enrolled. All the participants completed the Phramongkutklao(PMK) Hospital OSA Questionnaire that was modified and validated from the Berlin Questionnaire and underwent physical examination. The participants were 1107 active-duty army personnel in the three southernmost provinces of Thailand, both males and females, aged 20–60 years.Methods: The PMK OSA Questionnaire was used to assess the risk of OSA together with interviewing for snoring,fatigue, falling asleep and day-time sleepiness. Physical examination of the neck, chest and hip circumference,and height was performed. Information concerning physical training, co-morbid diseases, smoking and alcoholic consumption was collected.Results: The prevalence of snoring was 58.5, and 4.8% met the PMK OSA Questionnaire criteria, thus indicating a high risk of OSA. The information obtained indicated that laryngopharyngeal reflux(LPR), current smoking and alcoholic consumption were significantly higher in the high-risk OSA group.Conclusions: Early detection and treatment of OSA in active-duty army personnel are imperative. Physical examination and polysomnography can be used to reveal the high-risk group. High body mess index(BMI), laryngopharyngeal reflux, current smoking and alcoholic consumption are modifiable factors for OSA and are avoidable. A policy to decrease the BMI and risk of LPR, as well as to stop smoking and alcoholic consumption, should be applied. 展开更多
关键词 active-duty ARMY personnel Laryngopharyngeal reflux PREVALENCE QUESTIONNAIRE Snoring Obstructive sleep apnea
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Research on semi-active control method of a building structure based on non-smooth control 被引量:2
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作者 Wang Qing Wang Jianhui Ma Kemao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第2期425-432,共8页
This study investigates the effectiveness of the non-smooth semi-active control algorithm on suppressing the vibration performance of a building structure subjected to seismic waves. According to the Lyapunov stabilit... This study investigates the effectiveness of the non-smooth semi-active control algorithm on suppressing the vibration performance of a building structure subjected to seismic waves. According to the Lyapunov stability theory, it has bene proven that the non-smooth semi-active control algorithm can achieve a finite-time stability of the vibration relative to the isolation layer of a building structure. Through numerical simulation of two buildings with different parameters subjected to the input of a seismic wave, the vibration conditions of passive control, LQR semi-active control and non-smooth semiactive control are compared and analyzed. The simulation results show that the non-smooth semi-active control algorithm has a better robustness and effectiveness in restraining the impact of earthquakes on the structure. 展开更多
关键词 building structure ISOLATION layer SEMI-active CONTROL non-SMOOTH CONTROL VIBRATION
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Investigating College Students’ Diet and Physical Activity Behaviors Regarding Non-Communicable Diseases Prevention in China
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作者 Ling-Shen Hung Yueyuan Chen +2 位作者 Yuqi Huang Li-Ching Hung Meng-Te Hung 《Journal of Biosciences and Medicines》 CAS 2023年第2期302-310,共9页
We aimed to investigate if college students’ dietary and physical activity adhered to the Chinese Dietary Guidelines, the Composing Editorial Board of Physical Activity Guidelines, and WHO recommendation for NCDs pre... We aimed to investigate if college students’ dietary and physical activity adhered to the Chinese Dietary Guidelines, the Composing Editorial Board of Physical Activity Guidelines, and WHO recommendation for NCDs prevention. Methods: A 3-day (2 weekdays and 1 weekend day) 24-hour (24-HRs) dietary recall was conducted to record details of participants’ food consumption. One-way analysis of variance (ANOVA) was applied to examine the influence of the identified demographic variables (including BMI, gender, major, family monthly income, and place of household registration) on the 8 food groups’ consumption. We analyzed the effect of the various demographic variables on sodium intake by the student’s t-test. The questionnaire, International Physical Activity Questionnaire (IPAQ)-Short Form, was utilized to assess participants’ physical activity (PA) level. The Wilcoxon-Mann-Whitney was applied to analyze participants’ physical activity. Results: Our research indicated participants consumed much fewer fruits and vegetables and excessive meats on average for both males and females regarding NCDs prevention. Conclusion: Participants’ dietary intake did not comply with the Chinese Dietary Guide-lines recommendation for chronic diseases prevention. Nutrition knowledge and health education are needed for college students. . 展开更多
关键词 non-Communicable Diseases Dietary Behavior Physical activity College Students
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A novel digital control strategy of three-phase shunt active power filter under non-ideal mains voltages 被引量:1
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作者 胡志坤 陈志文 +2 位作者 华长春 王会海 丁家峰 《Journal of Central South University》 SCIE EI CAS 2011年第6期2021-2030,共10页
A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous... A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous reactive power theory based algorithm was unsatisfactory in terms of isolating positive sequence fundamental active components exactly under non-ideal mains voltages. So, a modified ip-iq reference current calculation method was presented. With usage of the new method, not only the positive sequence but also the fundamental active current components can be accurately isolated from load current. A deadbeat closed-loop control model is built in order to eliminate both delay error and tracking error between reference voltages and compensation voltages under unbalanced and distorted mains voltages. Computer simulation results show that the proposed strategy is effective with better tracking ability and lower total harmonic distortion (THD). The strategy is also applied to a 10 kV substation with a local electrolysis manganese plant injecting a large amount of harmonics into the power system, and is proved to be more practical and efficient. 展开更多
关键词 并联有源电力滤波器 电源电压 控制策略 非理想 三相 瞬时无功功率理论 计算机模拟 总谐波失真
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Piezoelectric Actuator/Sensor Wave Propagation Based Nondestructive Active Monitoring Method of Concrete Structures 被引量:5
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作者 朱劲松 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期541-547,共7页
In order to monitor the basic mechanical properties and interior damage of concrete structures,the piezoelectric actuator/sensor based wave propagation method was investigated experimentally in the laboratory using a ... In order to monitor the basic mechanical properties and interior damage of concrete structures,the piezoelectric actuator/sensor based wave propagation method was investigated experimentally in the laboratory using a specifically designed test setup.The energy attenuation of stress waves was measured by the relative index between the output voltage of sensors and the excitation voltage at the actuator.Based on the experimental results of concrete cube and cylinder specimens,the effect of excitation frequencies,excitation amplitude,wave propagation paths and the curing age on the output signals of sensors are evaluated.The results show that the relative voltage attenuation coefficient RVAC is an effective indicator for measuring the attenuation of stress waves through the interior of concrete. 展开更多
关键词 piezoceramics actuator/sensor wave propagation method non-destructive evaluation (NDE) active monitoring concrete
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Robust stability characterizations of active metamaterials with non-Foster loads
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作者 范逸风 孙永志 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期594-601,共8页
Active metamaterials incorporating with non-Foster elements have been considered as one of the means of overcoming inherent limitations of the passive counterparts, thus achieving broadband or gain metamaterials. Howe... Active metamaterials incorporating with non-Foster elements have been considered as one of the means of overcoming inherent limitations of the passive counterparts, thus achieving broadband or gain metamaterials. However, realistic active metamaterials, especially non-Foster loaded medium, would face the challenge of the possibility of instability. Moreover,they normally appear to be time-variant and in unsteady states, which leads to the necessity of a stability method to cope with the stability issue considering the system model uncertainty. In this paper, we propose an immittance-based stability method to design a non-Foster loaded metamaterial ensuring robust stability. First, the principle of this stability method is introduced after comparing different stability criteria. Based on the equivalent system model, the stability characterization is used to give the design specifications to achieve an active metamaterial with robust stability. Finally, it is applied to the practical design of active metamaterial with non-Foster loaded loop arrays. By introducing the disturbance into the nonFoster circuit(NFC), the worst-case model uncertainty is considered during the design, and the reliability of our proposed method is verified. This method can also be applied to other realistic design of active metamaterials. 展开更多
关键词 active metamaterials stability analysis non-Foster circuit(NFC)
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Comparative Study of Linear and Non-Linear Controls of Three-Phase Shunt Active Filters for Improving the Quality of Electrical Energy
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作者 Mamane Adamou Nabil Alkassoum +1 位作者 André Foulani Amadou Seidou Maiga 《Energy and Power Engineering》 2019年第3期149-166,共18页
The aim of this work is to comparatively study two types of control of a three-phase shunt active filter (TSAF) in order to realize a system of depollution of electrical networks so as to improve the quality of electr... The aim of this work is to comparatively study two types of control of a three-phase shunt active filter (TSAF) in order to realize a system of depollution of electrical networks so as to improve the quality of electrical energy. We used two TSA control models which differ in the method of disturbed currents detection, one linear and the other non-linear. The results show that the non-linear control method, although with high calculation blocks, gives more promising results than the linear control method. When connecting a non-linear load (televisions, lamps, variable speed drives, etc.) directly to the public distribution network, the non-linear nature of the load causes the source current to be deformed due to the presence of harmonic currents and voltages. These harmonics thus generate a high reactive power, and therefore considerable electrical losses in the network. One of the solutions to reduce losses on the electricity grid is to incorporate an electronic circuit called a filter into the electricity grid. This work carried out a comparative study of two types of control of a three-phase shunt active filter (TSAF) in order to carry out a system for cleaning up electricity networks in order to improve the quality of electrical energy. We used two TSA control models that differ in the method of detecting disturbed currents, one linear and the other non-linear. The results show that the non-linear control method, although with high calculation blocks, gives better results than the linear control method. 展开更多
关键词 Power QUALITY active THREE-PHASE SHUNT Filter non-LINEAR CONTROL LINEAR CONTROL
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基于平衡系数的Active Demons非刚性配准算法 被引量:9
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作者 薛鹏 杨佩 +2 位作者 曹祝楼 贾大宇 董恩清 《自动化学报》 EI CSCD 北大核心 2016年第9期1389-1400,共12页
经典的Active demons算法利用参考图像和浮动图像的梯度信息作为驱动力,并使用均化系数调节两种驱动力之间的强度.该算法克服了Demons算法单一使用参考图像的梯度信息作为驱动力的缺点,但是Active demons算法中的均化系数无法同时兼顾... 经典的Active demons算法利用参考图像和浮动图像的梯度信息作为驱动力,并使用均化系数调节两种驱动力之间的强度.该算法克服了Demons算法单一使用参考图像的梯度信息作为驱动力的缺点,但是Active demons算法中的均化系数无法同时兼顾大形变和小形变区域的准确配准,还会导致配准的收敛速度和精确度相互制约的问题.为此,本文提出一种新的Active demons非刚性配准算法.提出的算法在Active demons扩散方程中引入一个称为平衡系数的新参数,与均化系数联合调整驱动力,不仅可以兼顾图像中同时具有的大形变和小形变区域的准确配准,而且在一定程度上缓和了收敛速度和精确度相互制约的问题.为了进一步提高配准的收敛速度和精确度,避免陷入局部极值,在新的配准算法的实现中引入由粗到细的多分辨率策略.在Checkboard测试图像、自然图像和医学图像上的实验结果表明,提出的算法较经典的Active demons算法收敛速度更快,配准精度平均提高了54.28%,接近最新的TV-L1光流场图像配准算法的配准精度,解决了Active demons算法存在的问题. 展开更多
关键词 非刚性配准 active DEMONS算法 光流场图像配准 驱动力 多分辨率策略
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Have guidelines addressing physical activity been established in nonalcoholic fatty liver disease? 被引量:9
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作者 Carmine Finelli Giovanni Tarantino 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第46期6790-6800,共11页
The purpose of this review was to highlight, in relation to the currently accepted pathophysiology of non-alcoholic fatty liver disease (NAFLD), the known exercise habits of patients with NAFLD and to detail the benef... The purpose of this review was to highlight, in relation to the currently accepted pathophysiology of non-alcoholic fatty liver disease (NAFLD), the known exercise habits of patients with NAFLD and to detail the benefits of lifestyle modification with exercise (and/or physical activity) on parameters of metabolic syndrome. More rigorous, controlled studies of longer duration and defined histopathological end-points comparing exercise alone and other treatment are needed before better, evidence-based physical activity modification guidelines can be established, since several questions remain unanswered. 展开更多
关键词 脂肪肝病 酒精性 体力 肝疾病 病理组织学 代谢综合征 生理过程 生活方式
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Non-UV germicidal activity of fresh TiO_2 and Ag/TiO_2 被引量:3
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作者 LIU Lifen John Barford YEUNG King Lun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期700-706,共7页
Fresh TiO2 was found to possess a strong germicidal activity even without UV irradiation. Live Yeast (Saccharomyces cerevisiae) cells in contact with fresh TiO2 were found deformed and dead after 15min contact. The ... Fresh TiO2 was found to possess a strong germicidal activity even without UV irradiation. Live Yeast (Saccharomyces cerevisiae) cells in contact with fresh TiO2 were found deformed and dead after 15min contact. The cause of germicidal activity was discussed from the observed cell deformation, lysis and increased absorption at 1680 cm^-1 in FT-IR spectra of the affected cells, which proved the oxidizing effect of fresh TiO2 to cells. The deformation caused by the stretching of cell wail and pressure built-up inside the cell, led to cell burst and release of intracellular materials. The degree of cell deformation was found positively related with the wetting property of TiO2. Cells are negatively charged, for Gram-negative cell (thinner ceil wail), a higher germicidal effect was observed than Gram-positive cells. The germicidal effect of TiO2 gradually decreased after exposure to air at room temperature, as the wetting property decreased. This kind of germicidal activity was more effective compared to other germicidal process such as UVA/TiO2 or Ag+. This shed light on designing new germicidal material either maintained by visible light irradiation, or by oxidation effect generated by reactive oxygen species. 展开更多
关键词 germicidal activity titanium dioxide non-UV
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Histopathological differences utilizing the nonalcoholic fatty liver disease activity score criteria in diabetic(type 2 diabetes mellitus) and non-diabetic patients with nonalcoholic fatty liver disease 被引量:10
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作者 Bharat K Puchakayala Siddharth Verma +3 位作者 Pushpjeet Kanwar John Hart Raghavendra R Sanivarapu Smruti R Mohanty 《World Journal of Hepatology》 CAS 2015年第25期2610-2618,共9页
AIM: To study clinical and histopathological features of nonalcoholic fatty liver disease(NAFLD) in patients with and without type 2 diabetes mellitus(T2DM) using updated nonalcoholic steatohepatitis clinical research... AIM: To study clinical and histopathological features of nonalcoholic fatty liver disease(NAFLD) in patients with and without type 2 diabetes mellitus(T2DM) using updated nonalcoholic steatohepatitis clinical research network(NASH-CRN) grading system.METHODS: We retrospectively analyzed data of 235 patients with biopsy proven NAFLD with and without T2 DM.This database was utilized in the previously published study comparing ethnicity outcomes in NAFLD by the same corresponding author.The pathology database from University of Chicago was utilized for enrolling consecutive patients who met the criteria for NAFLD and their detailed clinical and histopathology findings were obtained for comparison.The relevant clinical profile of patients was collected from the Electronic Medical Records around the time of liver biopsy and the histology was read by a single well-trained histopathologist.The updated criteria for type 2 diabetes have been utilized for analysis.Background data of patients with NASH and NAFLD has been included.The mean differences were compared using χ2 and t-test along with regression analysis to evaluate the predictors of NASH and advanced fibrosis.RESULTS: Patients with NAFLD and T2 DM were significantly older(49.9 vs 43.0,P < 0.01),predominantly female(71.4 vs 56.3,P < 0.02),had higher rate of metabolic syndrome(88.7 vs 36.4,P < 0.01),had significantly higher aspartate transaminase(AST)/alanine transaminase(ALT) ratio(0.94 vs 0.78,P < 0.01) and Fib-4 index(1.65 vs 1.06,P < 0.01) as markers of NASH,showed higher mean NAFLD activity score(3.5 vs 3.0,P = 0.03) and higher mean fibrosis score(1.2 vs 0.52,P < 0.01) compared to patients with NAFLD without T2 DM.Furthermore,advanced fibrosis(32.5 vs 12.0,P < 0.01) and ballooning(27.3 vs 13.3,P < 0.01) was significantly higher among patients with NAFLD and T2 DM compared to patients with NAFLD without T2 DM.On multivariate analysis,T2 DM was independently associated with NASH(OR = 3.27,95%CI: 1.43-7.50,P < 0.01) and advanced fibrosis(OR = 3.45,95%CI: 1.53-7.77,P < 0.01) in all patients with NAFLD.There was a higher rate of T2DM(38.1 vs 19.4,P < 0.01) and cirrhosis(8.3 vs 0.0,P = 0.01) along with significantly higher mean Bilirubin(0.71 vs 0.56,P = 0.01) and AST(54.2 vs 38.3,P < 0.01) and ALT(78.7 vs 57.0,P = 0.01) level among patients with NASH when compared to patients with steatosis alone.The mean platelet count(247 vs 283,P < 0.01) and high-density lipoprotein cholesterol level(42.7 vs 48.1,P = 0.01) was lower among patients with NASH compared to patients with steatosis.CONCLUSION: Patients with NAFLD and T2 DM tend to have more advanced stages of NAFLD,particularly advanced fibrosis and higher rate of ballooning than patients with NAFLD without T2 DM. 展开更多
关键词 non-alcoholic STEATOHEPATITIS non-alcoholicfatty liver disease Advanced FIBROSIS non-alcoholicfatty live
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Active disturbance rejection control on first-order plant 被引量:20
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作者 Ruiguang Yang Mingwei Sun Zengqiang Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第1期95-102,共8页
Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection ... Conventional PI control encounters some problems when dealing with large lag process in the presence of parameter uncertainties.For the typical first-order process,an observerbased linear active disturbance rejection control(LADRC) scheme is presented to cope with the difficulties,and a reduced-order observer scheme is proposed further.Some quantitative dynamic results with regard to non-overshoot characteristics are obtained.Finally,the performance boundaries of LADRC and PI control are explicitly compared with each other,which shows that the former is more superior in most cases. 展开更多
关键词 active disturbance rejection control(ADRC) first-order process dynamic performance non-overshoot.
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Catalytic Effect of Activated Carbon and Activated Carbon Fiber in Non-Equilibrium Plasma-Based Water Treatment 被引量:2
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作者 张延宗 郑经堂 +2 位作者 曲险峰 于维钊 陈宏刚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期358-362,共5页
Catalysis and regeneration efficiency of granular activated carbon (GAC) and activated carbon fiber (ACF) were investigated in a non-equilibrium plasma water treatment reactor with a combination of pulsed streamer... Catalysis and regeneration efficiency of granular activated carbon (GAC) and activated carbon fiber (ACF) were investigated in a non-equilibrium plasma water treatment reactor with a combination of pulsed streamer discharge and GAC or ACF. The experimental results show that the degradation efficiency of methyl orange (MO) by the combined treatment can increase 22% (for GAC) and 24% (for ACF) respectively compared to pulsed discharge treatment alone, indicating that the combined treatment has a synergetic effect. The MO degradation efficiency by the combined treatment with pulsed discharge and saturated GAC or ACF can increase 12% and 17% respectively compared to pulsed discharge treatment alone. Both GAC and ACF show catalysis and the catalysis of ACF is prominent. Meanwhile, the regeneration of GAC and ACF are realized in this process. When H202 is introduced into the system, the utilization efficiency of ozone and ultraviolet light is improved and the regeneration efficiency of GAC and ACF is also increased. 展开更多
关键词 non-equilibrium plasma water treatment activated carbon activated carbon fiber catalytic effect
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Role of peroxisome proliferators-activated receptors in the pathogenesis and treatment of nonalcoholic fatty liver disease 被引量:34
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作者 Eric R Kallwitz Alan McLachlan Scott J Cotler 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期22-28,共7页
Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and can result in nonalcoholic steatohepatitis (NASH) and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of lite... Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and can result in nonalcoholic steatohepatitis (NASH) and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of literature implicates the peroxisome proliferators-activated receptors (PPARs) in the pathogenesis and treatment of NAFLD. These nuclear hormone receptors impact on hepatic triglyceride accumulation and insulin resistance. The aim of this review is to describe the data linking PPARα and PPARγ to NAFLD/NASH and to discuss the use of PPAR ligands for the treatment of NASH. 展开更多
关键词 非酒精性脂肪肝 发病机理 治疗方法 过氧物酶体
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Physical activity and nutrition attitudes in obese Hispanic children with non-alcoholic steatohepatitis 被引量:2
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作者 Lana N Hattar Theresa A Wilson +2 位作者 Leanel A Tabotabo E O'Brian Smith Stephanie H Abrams 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第39期4396-4403,共8页
AIM:To assess nutrition,physical activity and health-ful knowledge in obese children with biopsy-proven nonalcoholic steatohepatitis(NASH or NA)compared to children without liver disease.METHODS:Children with biopsy-p... AIM:To assess nutrition,physical activity and health-ful knowledge in obese children with biopsy-proven nonalcoholic steatohepatitis(NASH or NA)compared to children without liver disease.METHODS:Children with biopsy-proven NASH comprised the NASH group.Age,sex and ethnicity matched control groups consisted of obese(OB)and lean(CO) children with no liver disease.Subjects were adminis-tered the School Physical Activity and Nutrition Survey and one blood draw was obtained.RESULTS:Fifty-seven patients were enrolled with a mean age of 12.1±2.1 years,and all were Hispanic.Even though the OB and NA had a similar increased body mass index(%),35%of the NA group always read nutrition labels compared to none in the OB(P<0.05),and more NA children felt their diet is"less healthy".NA consumed the least amount of fruits with only 25%having≥1 fruit/d vs 45%in OB and 64.7% in CO(P<0.05 NA vs CO).Only 15%of NA subjects performed light exercise vs 35%and 59%of OB and CO groups,respectively(P=0.02).The mean physical activity score was lowest in the NA group(P<0.05).Amongst the subjects with NASH,we found that 100% of patients with grade 2 or 3 fibrosis had a sedentary score>2 compared to only 63.6%of those with grade 1 or no fibrosis(P<0.05).CONCLUSION:Children with NASH had increased sedentary behavior,decreased activity,and fruit intake.Larger studies may determine the benefit of changing these behaviors as treatment for NASH. 展开更多
关键词 营养调查 西班牙 酒精性 儿童 体育锻炼 肥胖 肝炎 脂肪
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Electrocatalytic activity of non-precious metal catalyst Co-N/C toward oxygen reduction reaction 被引量:2
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作者 Yu Jun Si Chang Guo Chen +1 位作者 Wei Yin Hui Cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期983-986,共4页
Metallic cobalt was deposited on acetylene black to synthesize a composite Co/C by chemical reduction method.A platinumfree electrocatalyst Co-N/C(800) for oxygen reduction reaction(ORR) was synthesized by mixing ... Metallic cobalt was deposited on acetylene black to synthesize a composite Co/C by chemical reduction method.A platinumfree electrocatalyst Co-N/C(800) for oxygen reduction reaction(ORR) was synthesized by mixing the composite Co/C with urea and heat-treating at 800℃.The results from linear sweep voltammograms indicated that the Co-N/C(800) is active to ORR.Theβ-Co and cobalt oxides are not the active site of the catalyst Co-N/C.However,the existence of cobalt facilitated the modification of nitrogen to carbon black and led to the formation of active site of catalyst Co-N/C(800). 展开更多
关键词 Oxygen reduction reaction ELECTROCATALYST non-precious metal active site
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Peroxisome proliferator-activated receptors as targets to treat non-alcoholic fatty liver disease 被引量:19
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作者 Vanessa Souza-Mello 《World Journal of Hepatology》 CAS 2015年第8期1012-1019,共8页
Lately, the world has faced tremendous progress in the understanding of non-alcoholic fatty liver disease(NAFLD) pathogenesis due to rising obesity rates. Peroxisome proliferator-activated receptors(PPARs) are transcr... Lately, the world has faced tremendous progress in the understanding of non-alcoholic fatty liver disease(NAFLD) pathogenesis due to rising obesity rates. Peroxisome proliferator-activated receptors(PPARs) are transcription factors that modulate the expression of genes involved in lipid metabolism, energy homeostasis and inflammation, being altered in diet-induced obesity. Experimental evidences show that PPAR-alpha is the master regulator of hepatic beta-oxidation(mitochondrial and peroxisomal)and microsomal omega-oxidation, being markedly decreased by high-fat(HF) intake. PPAR-beta/delta is crucial to the regulation of forkhead box-containing protein O subfamily-1 expression and, hence, the modulation of enzymes that trigger hepatic gluconeogenesis. In addition, PPAR-beta/delta can activate hepatic stellate cells aiming to the hepatic recovery from chronic insult. On the contrary, PPAR-gamma upregulation by HF diets maximizes NAFLD through the induction of lipogenic factors, which are implicated in the fatty acid synthesis. Excessive dietary sugars also upregulate PPAR-gamma, triggering de novo lipogenesis and the consequent lipid droplets deposition within hepatocytes. Targeting PPARs to treat NAFLD seems a fruitful approach as PPAR-alpha agonist elicits expressive decrease in hepatic steatosis by increasing mitochondrial beta-oxidation, besides reduced lipogenesis. PPAR-beta/delta ameliorates hepatic insulin resistance by decreasing hepatic gluconeogenesis at postprandial stage. Total PPAR-gamma activation can exert noxious effects by stimulating hepatic lipogenesis. However, partial PPAR-gamma activation leads to benefits, mainly mediated by increased adiponectin expression and decreased insulin resistance. Further studies are necessary aiming at translational approaches useful to treat NAFLD in humans worldwide by targeting PPARs. 展开更多
关键词 PEROXISOME proliferator-activated receptors non-alcoholic FATTY liver disease Obesity Treatment Insulin resistance BETA-OXIDATION LIPOGENESIS
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Effects of light intensities and photoperiods on growth and proteolytic activity in purple non-sulfur marine bacterium, <i>Afifella marina</i>strain ME (KC205142) 被引量:6
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作者 Sujjat Al-Azad Tan Kar Soon Julian Ransangan 《Advances in Bioscience and Biotechnology》 2013年第10期919-924,共6页
Afifella marina strain ME (KC205142), a purple non-sulfur bacterium was isolated from mangrove habitats of Sabah. The effects of light intensities and photoperiods on proteolytic activity in Afifella marina strain ME ... Afifella marina strain ME (KC205142), a purple non-sulfur bacterium was isolated from mangrove habitats of Sabah. The effects of light intensities and photoperiods on proteolytic activity in Afifella marina strain ME (KC205142) were investigated. Secretion of proteolytic enzymes in Afifella marina was preliminarily assessed by skim milk agarose media. Subsequently, light intensities, such as, dark, 1000, 1500, 2000, 2500, 3000, 3500, 4000, 4500 and 5000 lux were used to evaluate the effects on proteolytic activity in Afifella marina strain ME under anaerobic condition. After that, the effect of photoperiods on proteolytic activity was monitored under anaerobic light condition (3000 lux) at 0 h (0L/24D), 6 h (6L/18D), 12 h (12L/12D), 18 h (18L/6D) and 24 h (24L/0D) of photoperiod. The highest proteolytic activity of 74.67 U was recorded at 3000 lux illumination light intensity. The proteolytic activity in bacterium Afifella marina strain ME was positively associated with the dry cell weight. The proteolytic activity of 72.67 U in bacterium Afifella marina strain ME at 18 h (18L/6D) photoperiod is not significantly different (p > 0.05) from proteolytic activity of 74.67 U recorded at continuous light (24L/0D) condition. Light intensity of 3000 lux, culture period of 48 h and a photoperiod of 18 h (18L/ 6D) were the optimum parameters for proteolytic activity in bacterium Afifella marina strain ME. 展开更多
关键词 Afifella MARINA LIGHT Intensity Photoperiod Proteolytic activity PURPLE non-SULFUR Bacteria
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Green tea polyphenols ameliorate non-alcoholic fatty liver disease through upregulating AMPK activation in high fat fed Zucker fatty rats 被引量:11
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作者 Yi Tan Jane Kim +7 位作者 Jing Cheng Madeleine Ong Wei-Guo Lao Xing-Liang Jin Yi-Guang Lin Linda Xiao Xue-Qiong Zhu Xian-Qin Qu 《World Journal of Gastroenterology》 SCIE CAS 2017年第21期3805-3814,共10页
AIM To investigate protective effects and molecular mechanisms of green tea polyphenols(GTP) on nonalcoholic fatty liver disease(NAFLD) in Zucker fatty(ZF) rats.METHODS Male ZF rats were fed a high-fat diet(HFD) for 2... AIM To investigate protective effects and molecular mechanisms of green tea polyphenols(GTP) on nonalcoholic fatty liver disease(NAFLD) in Zucker fatty(ZF) rats.METHODS Male ZF rats were fed a high-fat diet(HFD) for 2 wk then treated with GTP(200 mg/kg) or saline(5 m L/kg) for 8 wk, with Zucker lean rat as their control. At the end of experiment, serum and liver tissue were collected for measurement of metabolic parameters, alanine aminotransferase(ALT) and aspartate aminotransferase(AST), inflammatory cytokines and hepatic triglyceride and liver histology. Immunoblotting was used to detect phosphorylation of AMP-activated protein kinase(AMPK) acetyl-Co A carboxylase(ACC), and sterol regulatory element-binding protein 1c(SREBP1c). RESULTS Genetically obese ZF rats on a HFD presented with metabolic features of hepatic pathological changes comparable to human with NAFLD. GTP intervention decreased weight gain(10.1%, P = 0.052) and significantly lowered visceral fat(31.0%, P < 0.01). Compared with ZF-controls, GTP treatment significantly reduced fasting serum insulin, glucose and lipids levels. Reduction in serum ALT and AST levels(both P < 0.01) were observed in GTP-treated ZF rats. GTP treatment also attenuated the elevated TNFα and IL-6 in the circulation. The increased hepatic TG accumulation and cytoplasmic lipid droplet were attenuated by GTP treatment, associated with significantly increased expression of AMPK-Thr172(P < 0.05) and phosphorylated ACC and SREBP1c(both P < 0.05), indicating diminished hepatic lipogenesis and triglycerides out flux from liver in GTP treated rats. CONCLUSION The protective effects of GTP against HFD-induced NAFLD in genetically obese ZF rats are positively correlated to reduction in hepatic lipogenesis through upregulating the AMPK pathway. 展开更多
关键词 non-alcoholic fatty liver disease Green tea polyphenols Hepatic lipogenesis Inflammatory cytokines AMP-activated protein kinase
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Role of CD59 in T cell activation induced by non-lethal complement attack 被引量:1
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作者 韩根成 白云 +2 位作者 姜曼 黎万玲 朱锡华 《Journal of Medical Colleges of PLA(China)》 CAS 2001年第1期19-23,共5页
Objective: To study the mechanism of T-cell activation induced by non-lethal complement attack and the role of CD59 in this process. Methods: Human CD59 and its transmentbrane counterpart CD59TM cDNA were transfected ... Objective: To study the mechanism of T-cell activation induced by non-lethal complement attack and the role of CD59 in this process. Methods: Human CD59 and its transmentbrane counterpart CD59TM cDNA were transfected into murine thymoma EL-4 cells. Activation and proliferation of EL-4 transfectants were observed with MIT assay. Results:Both CD59 and CD59 TM cDNA expressed on EL-4 cells effectively inhibited complement-mediated membrane damage. Cross-linking of CD59 with antibody induced activation of CD59/EL-4 cells but not CDS9TM/EL-4 cells. This effect was inhibited by Herbimycin A. a special protein tyrosine kinase (PTK) inhibitor. Non-lethal complement attack induced CD59/EL-4 but not CD59TMIEL-4 cell to proliferate, and this reaction was not blocked by Herbimycin A. Conclusion: CD59 takes part in T cell activation induced by non-lethal complement attack. The mechanisms of T cell activation induced by non-lethal complement attack arc different from those by cross-linking of CD59. 展开更多
关键词 CD59 T细胞活化 EL-4 CD59TM 病理学
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