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51.
Chen X Sekine M Hamanishi S Wang H Gaina A Yamagami T Kagamimori S 《Journal of epidemiology / Japan Epidemiological Association》2003,13(5):278-287
BACKGROUND: There is little information about validation of young children's self-reported physical activity. This study assessed the validity of a self-reported questionnaire designed to measure children's physical activity. METHODS: Subjects were 34 boys from 4th to 6th grade of a public elementary school. Contents of the self-reported physical activity questionnaire included participation in sports club, physical activity intensity, preference for physical activity, and frequency of physical activity. Subjects were equipped with a Lifecorder and an Actiwatch for 7 consecutive days to monitor physical activity. Physical activity index was calculated from the Lifecorder data of total energy expenditure per day (TEE) divided by basal metabolic rate. Unpaired t-test, analysis of variance, and multiple linear regression analysis were performed to clarify the relationship between the objective and subjective data. RESULTS: Subjects who reported participation in a sports club had a higher physical activity index and energy expenditure originating from physical activity than those who did not. Those characterized by a "vigorous" physical activity intensity had a higher physical activity index (1.63 +/- 0.08), when compared with peers in "moderate" (1.59 +/- 0.06) or "light" categories (1.54 +/- 0.07) (p for linear trend p < 0.05). A high frequency of physical activity was significantly associated with an increasing trend in energy expenditure originating from physical activity, steps, and activity counts. Preference for physical activity was significantly related to data from the Lifecorder and the Actiwatch. CONCLUSIONS: Schoolchildren's self-reported physical activity is in accordance with the objective data, and could be used as a valid measure to evaluate physical activity level in school settings. 相似文献
52.
Jin Z Cheng Y Olaru A Kan T Yang J Paun B Ito T Hamilton JP David S Agarwal R Selaru FM Sato F Abraham JM Beer DG Mori Y Shimada Y Meltzer SJ 《International journal of cancer. Journal international du cancer》2008,123(10):2331-2336
Although the CDH13 gene has been shown to undergo epigenetic silencing by promoter methylation in many types of tumors, hypermethylation of this gene in Barrett's-associated esophageal adenocarcinogenesis has not been studied. Two hundred fifty-nine human esophageal tissues were therefore examined for CDH13 promoter hypermethylation by real-time methylation-specific PCR. CDH13 hypermethylation showed discriminative receiver-operator characteristic curve profiles, sharply demarcating esophageal adenocarcinoma (EAC) from esophageal squamous cell carcinoma (ESCC) and normal esophagus (NE) (p < 0.0001). CDH13 normalized methylation values (NMV) were significantly higher in Barrett's esophagus (BE), dysplastic BE (D) and EAC than in NE (p < 0.0000001). CDH13 hypermethylation frequency was 0% in NE but increased early during neoplastic progression, rising to 70% in BE, 77.5% in D and 76.1% in EAC. Both CDH13 hypermethylation frequency and its mean NMV were significantly higher in BE with than without accompanying EAC. In contrast, only 5 (19.2%) of 26 ESCCs exhibited CDH13 hypermethylation. Furthermore, both CDH13 hypermethylation frequency and its mean NMV were significantly higher in EAC than in ESCC, as well as in BE or D vs. ESCC. Interestingly, mean CDH13 NMV was significantly lower in short-segment than in long-segment BE, a known clinical risk factor for neoplastic progression. Similarly, BE segment length was significantly lower in specimens with unmethylated than with methylated CDH13 promoters. 5-aza-2'-deoxycytidine treatment of OE33 EAC and KYSE220 ESCC cells reduced CDH13 methylation and increased CDH13 mRNA expression. These findings suggest that hypermethylation of CDH13 is a common, tissue-specific event in human EAC, occurs early during BE-associated neoplastic progression, and correlates with known clinical neoplastic progression risk factors. 相似文献
53.
54.
Graham Peigh MD Jeremiah Wasserlauf MD MS Kelly Vogel BS Rachel M. Kaplan MD MS Anna Pfenniger MD PhD Daniel Marks MD Arjun Mehta MD Alexandru B. Chicos MD Rishi Arora MD Susan Kim MD Albert Lin MD Nishant Verma MD MPH Kaustubha D. Patil MD Bradley P. Knight MD Rod S. Passman MD MSCE 《Journal of cardiovascular electrophysiology》2021,32(8):2097-2104
55.
François-Pierrick Desgranges Etienne Javouhey Carmine Mottolese Anne Migeon Alexandru Szathmari Florent Baudin Mathilde de Queiroz Bérengère Cogniat Dominique Chassard 《Child's nervous system》2014,30(8):1393-1398
Purpose
There are no data available on the risk of intraoperative bleeding during decompressive craniectomy (DC) after traumatic brain injury (TBI) in children. The objectives of this study were to assess the risk of intraoperative bleeding during DC for intractable intracranial hypertension after TBI, to identify potential factors associated with the risk of bleeding during DC, and to assess the impact of DC on systemic and cerebral hemodynamics and on coagulation.Methods
Twelve children were identified as having undergone DC after TBI from April 2009 to June 2013 in our center. Subjects were allocated into two groups according to the percentage of blood loss (IBL) during the intraoperative period (<or ≥50 % of the estimated blood volume (EBV)).Results
The median IBL during DC was 49 [17–349] % of the EBV. Children with an IBL?≥?50 % of EBV had higher preoperative intracranial pressure (ICP) (p?=?0.03) and international normalized ratio (INR) (p?=?0.02) than those with an IBL?<?50 % of EBV. DC induced significant decreases in ICP (p?=?0.0005), mean arterial pressure (p?=?0.01), and a significant increase in norepinephrine flow rate (p?=?0.04) between the immediate pre- and postoperative periods.Conclusions
DC allows a significant decrease in ICP after severe pediatric TBI but is a surgical procedure at a high risk of bleeding. High ICP and INR during the immediate preoperative period are the main factors associated with increased IBL during DC. Further studies are needed to confirm our results and to assess the impact of the amount of IBL on the postoperative survival and functional outcome. 相似文献56.
57.
Graphene supports in vitro proliferation and osteogenic differentiation of goat adult mesenchymal stem cells: potential for bone tissue engineering 下载免费PDF全文
Hoda Elkhenany Lisa Amelse Andersen Lafont Shawn Bourdo Marc Caldwell Nancy Neilsen Enkeleda Dervishi Oshin Derek Alexandru S. Biris David Anderson Madhu Dhar 《Journal of applied toxicology : JAT》2015,35(4):367-374
Current treatments for bone loss injuries involve autologous and allogenic bone grafts, metal alloys and ceramics. Although these therapies have proved useful, they suffer from inherent challenges, and hence, an adequate bone replacement therapy has not yet been found. We hypothesize that graphene may be a useful nanoscaffold for mesenchymal stem cells and will promote proliferation and differentiation into bone progenitor cells. In this study, we evaluate graphene, a biocompatible inert nanomaterial, for its effect on in vitro growth and differentiation of goat adult mesenchymal stem cells. Cell proliferation and differentiation are compared between polystyrene‐coated tissue culture plates and graphene‐coated plates. Graphitic materials are cytocompatible and support cell adhesion and proliferation. Importantly, cells seeded on to oxidized graphene films undergo osteogenic differentiation in fetal bovine serum‐containing medium without the addition of any glucocorticoid or specific growth factors. These findings support graphene's potential to act as an osteoinducer and a vehicle to deliver mesenchymal stem cells, and suggest that the combination of graphene and goat mesenchymal stem cells provides a promising construct for bone tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
58.
Carina Ureche Radu Sascu Laura
poi Andreea Covic Corneliu Moroanu Luminia Voroneanu Alexandru Burlacu Cristian Sttescu Adrian Covic 《Echocardiography (Mount Kisco, N.Y.)》2019,36(7):1372-1380
Cardiovascular disease (CVD) is the leading cause of death worldwide and is particularly frequent among those with severe renal impairment. Early diagnosis and therapeutic intervention may help alleviate the burden of cardiovascular complication within this population. In the last years, advances have been made toward developing noninvasive imaging techniques that could offer better insight into the cardiac involvement in end‐stage renal disease (ESRD). Conventional transthoracic echocardiography remains the first‐line investigation used to assess cardiac function, but encompassing in our daily practice, the newer approaches such as speckle‐tracking imaging, cardiac computed tomography, or cardiac magnetic resonance can guide us to a more comprehensive understanding of CVD in ESRD. Given that patients with chronic kidney disease may not present with typical CVD symptoms, the amount of information brought by newer imaging techniques is crucial for an accurate diagnosis, risk stratification, and further management. The purpose of this review is to briefly summarize the specific applications of standard cardiac imaging techniques in patients with ESRD and to offer insight into the novel imaging modalities, highlighting the newest research in this field. By doing so, we aim to identify the most important imaging predictors of clinical outcomes in this population. 相似文献
59.
Christopher D. Crabtree Madison L. Kackley Alexandru Buga Brandon Fell Richard A. LaFountain Parker N. Hyde Teryn N. Sapper William J. Kraemer Debbie Scandling Orlando P. Simonetti Jeff S. Volek 《Nutrients》2021,13(3)
Ketogenic diets (KDs) often contain high levels of saturated fat, which may increase liver fat, but the lower carbohydrate intake may have the opposite effect. Using a controlled feeding design, we compared liver fat responses to a hypocaloric KD with a placebo (PL) versus an energy-matched low-fat diet (LFD) in overweight adults. We also examined the added effect of a ketone supplement (KS). Overweight adults were randomized to a 6-week KD (KD + PL) or a KD with KS (KD + KS); an LFD group was recruited separately. All diets were estimated to provide 75% of energy expenditure. Weight loss was similar between groups (p > 0.05). Liver fat assessed by magnetic resonance imaging decreased after 6 week (p = 0.004) with no group differences (p > 0.05). A subset with nonalcoholic fatty liver disease (NAFLD) (liver fat > 5%, n = 12) showed a greater reduction in liver fat, but no group differences. In KD participants with NAFLD, 92% of the variability in change in liver fat was explained by baseline liver fat (p < 0.001). A short-term hypocaloric KD high in saturated fat does not adversely impact liver health and is not impacted by exogenous ketones. Hypocaloric low-fat and KDs can both be used in the short-term to significantly reduce liver fat in individuals with NAFLD. 相似文献
60.