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BackgroundUltramarathon is a high endurance exercise associated with a wide range of exercise-related problems, such as acute kidney injury (AKI). Early recognition of individuals at risk of AKI during ultramarathon event is critical for implementing preventative strategies.ObjectivesTo investigate the impact of speed variability to identify the exercise-related acute kidney injury anticipatively in ultramarathon event.MethodsThis is a prospective, observational study using data from a 100 km ultramarathon in Taipei, Taiwan. The distance of entire ultramarathon race was divided into 10 splits. The mean and variability of speed, which was determined by the coefficient of variation (CV) in each 10 km-split (25 laps of 400 m oval track) were calculated for enrolled runners. Baseline characteristics and biochemical data were collected completely 1 week before, immediately post-race, and one day after race. The main outcome was the development of AKI, defined as Stage II or III according to the Acute Kidney Injury Network (AKIN) criteria. Multivariate analysis was performed to determine the independent association between variables and AKI development.Results26 ultramarathon runners were analyzed in the study. The overall incidence of AKI (in all Stages) was 84.6% (22 in 26 runners). Among these 22 runners, 18 runners were determined as Stage I, 4 runners (15.4%) were determined as Stage II, and none was in Stage III. The covariates of BMI (25.22 ± 2.02 vs. 22.55 ± 1.96, p = 0.02), uric acid (6.88 ± 1.47 vs. 5.62 ± 0.86, p = 0.024), and CV of speed in specific 10-km splits (from secondary 10 km-split (10th – 20th km-split) to 60th – 70th km-split) were significantly different between runners with or without AKI (Stage II) in univariate analysis and showed discrimination ability in ROC curve. In the following multivariate analysis, only CV of speed in 40th – 50th km-split continued to show a significant association to the development of AKI (Stage II) (p = 0.032).ConclusionsThe development of exercise-related AKI was not infrequent in the ultramarathon runners. Because not all runners can routinely receive laboratory studies after race, variability of running speed (CV of speed) may offer a timely and efficient tool to identify AKI early during the competition, and used as a surrogate screening tool, at-risk runners can be identified and enrolled into prevention trials, such as adequate fluid management and avoidance of further NSAID use.  相似文献   
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PurposeTo investigate the distribution of the (CCR) and its associated factors in children.MethodsUsing a random cluster sampling method, the school-based, cross-sectional Shandong Children Eye Study included children aged 4 to 18 years from the rural county of Guanxian and the city of Weihai in the province of Shandong in East China. CCR was measured by ocular biometry.ResultsCCR measurements were available for 5913 (92.9%) out of 6364 eligible children. Mean age was 10.0±3.3 years, and mean CCR was 7.84±0.27 mm (range: 6.98 to 9.35 mm). In multivariate linear regression analysis, longer CCR (i.e. flatter cornea) was significantly associated with the systemic parameters of male sex (P<0001;standardized regression coefficient beta: -0.08;regression coefficient B:-0.04; 95% Confidence Interval (CI):-0.05,-0.03), younger age (P<0.001;beta:-0.37;B:-0.03;95%CI:-0.04,-0.03), taller body height (P = 0.002;beta:0.06;B:0.001;95%CI:0.000,0.001), lower level of education of the father (P = 0.001;beta:-0.04;B:-0.01;95%CI:-0.02,-0.01) and maternal myopia (P<0.001;beta:-0.07;B:-0.04;95%CI:-0.06,-0.03), and with the ocular parameters of longer ocular axial length (P<0.001;beta:0.59;B:0.13;95%CI:0.12,0.14), larger horizontal corneal diameter (P<0.001;beta:0.19;B:0.13;95%CI:0.11,0.14), and smaller amount of cylindrical refractive error (P = 0.001;beta:-0.09;B:-0.05;95%CI:-0.06,-0.04).ConclusionsLonger CCR (i.e., flatter corneas) (mean:7.84±0.27mm) was correlated with male sex, younger age, taller body height, lower paternal educational level, maternal myopia, longer axial length, larger corneas (i.e., longer horizontal corneal diameter), and smaller amount of cylindrical refractive error. These findings may be of interest for elucidation of the process of emmetropization and myopization and for corneal refractive surgery.  相似文献   
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BackgroundRetinal microvascular signs may provide insights into the structure and function of small vessels that are associated with renal disease. We examined the relationship of retinal microvascular signs with both prevalent and incident end-stage renal disease (ESRD) in a multi-ethnic Asian population.MethodsA total of 5763 subjects (aged ≥40 years) from two prospective population-based studies (the Singapore Malay Eye Study and the Singapore Prospective Study) were included for the current analysis. Retinopathy was graded using the modified Airlie House classification system. Retinal vascular parameters were measured using computer-assisted programs to quantify the retinal vessel widths (arteriolar and venular caliber) and retinal vascular network (fractal dimension). Data on ESRD was obtained by record linkage with the ESRD cases registered by National Registry of Diseases Office, Singapore. Multi-variable adjusted regression analyses were performed to assess the associations of baseline retinal vascular parameters and prevalent and incident ESRD.ResultsAt baseline, 21(0.36%) persons had prevalent ESRD. During a median follow-up of 4.3 years, 33 (0.57%) subjects developed ESRD. In our analyses, retinopathy was associated with prevalent ESRD (multi-variable adjusted odds ratio [OR], 3.21, 95% confidence interval [CI]: 1.28–8.05) and incident ESRD (multi-variable adjusted hazard ratio [HR], 2.51, 95%CI: 1.14–5.54). This association was largely seen in person with diabetes (HR, 2.60, 95%CI: 1.01–6.66) and not present in persons without diabetes (HR, 1.65, 95%CI: 0.14–18.98). Retinal arteriolar caliber, retinal venular caliber and retinal vascular fractal dimension were not associated with ESRD.ConclusionRetinopathy signs in persons with diabetes are related to an increased risk of ESRD; however, other microvascular changes in the retina are not associated with ESRD.  相似文献   
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Objective

To examine the adjusted associations of fruit consumption and vegetable consumption with the Framingham score and its components in the non-Western setting of Southern China, considering health status.

Method

Linear regression was used to assess the cross-sectional associations of fruit and vegetable consumption with the Framingham score and its components, among 19,518 older Chinese (≥50 years) from the Guangzhou Biobank Cohort Study in Southern China (2003–2006), and whether these differed by health status.

Results

The association of fruit consumption with the Framingham score varied by health status (P-value<0.001), but not vegetable consumption (P-value 0.51). Fruit consumption was associated with a lower Framingham score (-0.04 per portions/day, 95% confidence interval (CI) -0.08 to -0.004) among participants in poor health, adjusted for age, sex, recruitment phase, socio-economic position and lifestyle. However, similarly adjusted, fruit consumption was associated with a higher Framingham score (0.05, 95% CI 0.02 to 0.09) among participants in good health, perhaps due to a positive association of fruit consumption with fasting glucose. Similarly adjusted, vegetable consumption was associated with a higher Framingham score (0.03, 95% CI 0.01 to 0.05) among all participants, with no difference by health status.

Conclusion

This large study from a non-western setting found that fruit and vegetable consumption was barely associated with the Framingham score, or major CVD risk factors.  相似文献   
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湖南鹅膏属(蘑菇目)标本的订正   总被引:5,自引:0,他引:5  
对采于湖南现存湖南师范大学真菌标本室 (MHHNU)和中国科学院微生物研究所真菌标本室 (HMAS)的鹅膏属标本进行了研究 ,发现有不少标本鉴定有误 ,需要订正。本文对 16种鹅膏的分类问题进行了讨论 ,对鲜为人知的湖南鹅膏A hunanensis进行了详细描述。湖南鹅膏隶属于橙盖鹅膏组sect.Caesareae ,其主要特点是担子果中等至大型 ;菌盖灰色至褐色 ,具深色花斑 ,边缘有较长的沟纹 ;菌褶白色 ,褶缘灰褐色 ;菌柄有菌环、被蛇皮状灰褐色鳞片 ;菌托白色 ,其中含有丰富的膨大细胞 ;担子基部有锁状联合 ;担孢子椭圆形 ,非淀粉质 ,(8 0 ) 9 5~ 12 5 (15 5 )× 6 5~ 8 5 (10 0 ) μm。  相似文献   
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Despite potent insulin‐sensitizing, anti‐inflammatory, and antiatherogenic effects in animal studies, the relationship between serum adiponectin level and coronary artery disease in patients remains unclear. We determined the adiponectin profile in a cohort of multiethnic Asian patients with coronary artery disease, and the association between serum adiponectin level and culprit lesion necrotic core (NC) content. Ninety‐four Asian patients (BMI, 25.3 ± 3.7 kg/m2) undergoing percutaneous coronary intervention were recruited. The serum adiponectin level was measured (n = 94), and the baseline virtual histology intravascular ultrasound examination was analyzed (n = 88). The median level of adiponectin was 3.7 µg/ml (interquartile range, 2.8–4.5 µg/ml). The serum adiponectin level was below 10 µg/ml in 90 patients (95.7%) and below 6 µg/ml in 80 patients (85.1%). There was a significant association between ethnicity and serum adiponectin level (P = 0.048). The median adiponectin level was highest among the Chinese, followed by the Malay and the Indians. Serum adiponectin levels were positively associated with culprit lesion NC content. A 1‐µg/ml increase in log adiponectin was associated with a 3.04% (95% confidence interval: 0.33–5.44) increase in culprit lesion NC content. This association remains significant after adjusting for age, sex, ethnicity, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol, and procedural indication. We found a low serum level of adiponectin in Asian patients and a significant ethnic effect on serum adiponectin level. Increased serum adiponectin levels were independently associated with increased culprit lesion NC burden, suggesting a role for adiponectin in modulating coronary plaque vulnerability.  相似文献   
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The pH-modified citrus pectin (MCP) has been demonstrated to inhibit galectin-3 in cancer progression. The components and structures of MCP related to this inhibition remained unknown. In this paper, we fractionated MCP on DEAE-cellulose column into a homogenous neutral fraction MCP-N (about 20?kDa) and a pectin mixture fraction MCP-A (wide molecular distribution on Sepharose CL-6B chromatography). Both MCP-N and MCP-A inhibited hemagglutination mediated by galectin-3 with minimum inhibition concentration (MIC) 625 and 0.5?μg/ml, respectively. MCP-N was identified to be a type I arabinogalactan (AG-I) with a main chain of β-1→4-galactan. MCP-N was digested by α-L-arabinofuranosidase to give its main chain structure fraction (M-galactan, around 18?kDa), which was more active than the original molecule, MIC 50?μg/ml. The acidic degradation of M-galactan increased the inhibitory activity, MIC about 5 times lower than M-galactan. These results above showed that the functional motif of the β-1→4-galactan fragment might lie in the terminal residues rather than in the internal region of the chain. Therefore, MCP-N and its degraded products might be developed to new potential galectin-3 inhibitors. This is the first report concerning the fractionation of MCP and its components on galectin-3 inhibition. The information provided in this paper is valuable for screening more active galectin-3 inhibitors from natural polysaccharides.  相似文献   
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In this review, we describe recent efforts to systematically study nano-structured metal organic frameworks (MOFs), also known as metal organic heat carriers, with particular emphasis on their application in heating and cooling processes. We used both molecular dynamics and grand canonical Monte Carlo simulation techniques to gain a molecular-level understanding of the adsorption mechanism of gases in these porous materials. We investigated the uptake of various gases such as refrigerants R12 and R143a. We also evaluated the effects of temperature and pressure on the uptake mechanism. Our computed results compared reasonably well with available measurements from experiments, thus validating our potential models and approaches. In addition, we investigated the structural, diffusive and adsorption properties of different hydrocarbons in Ni2(dhtp). Finally, to elucidate the mechanism of nanoparticle dispersion in condensed phases, we studied the interactions among nanoparticles in various liquids, such as n-hexane, water and methanol.  相似文献   
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