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排序方式: 共有356条查询结果,搜索用时 31 毫秒
1.
多孔碳酸化羟基磷灰石骨水泥的生物相容性研究 总被引:2,自引:0,他引:2
目的探讨一种新型的代骨材料--多孔碳酸化羟基磷灰石骨水泥的组织相容性.方法合成碳酸化羟基磷灰石骨水泥,添加成孔剂,制备能原位固化形成多孔结构的碳酸化羟基磷灰石代骨材料,并通过细胞毒性实验和肌内埋植实验检测其组织相容性.结果多孔碳酸化羟基磷灰石骨水泥的浸提液对骨髓基质细胞的生长无影响.细胞于材料表面的生长速度、形态与空白对照组无差别.肌内植入实验发现,材料周围纤维组织包膜的最大厚度为22.5μm,未发现炎性细胞反应.结论多孔碳酸化羟基磷灰石骨水泥具有良好的组织相容性,材料测试结果符合和标准. 相似文献
2.
Robert Murray John G. Seifert Dennis E. Eddy Gregory L. Paul George A. Halaby 《European journal of applied physiology》1989,59(1-2):152-158
Summary The purpose of this study was to determine the effect of ingesting fluids of varying carbohydrate content upon sensory response,
physiologic function, and exercise performance during 1.25 h of intermittent cycling in a warm environment (T
db=33.4°C). Twelve subjects (7 male, 5 female) completed four separate exercise sessions; each session consisted of three 20
min bouts of cycling at 65%
, with each bout followed by 5 min rest. A timed cycling task (1200 pedal revolutions) completed each exercise session. Immediately
prior to the first 20 min cycling bout and during each rest period, subjects consumed 2.5 ml·kg BW−1 of water placebo (WP), or solutions of 6%, 8%, or 10% sucrose with electrolytes (20 mmol·l−1 Na+, 3.2 mmol·l−1 K+). Beverages were administered in double blind, counterbalanced order. Mean (±SE) times for the 1200 cycling task differed
significantly: WP=13.62±0.33 min, *6%=13.03±0.24 min, 8%=13.30±0.25 min, 10%=13.57±0.22 min (*=different from WP and 10%,P<0.05). Compared to WP, ingestion of the CHO beverages resulted in higher plasma glucose and insulin concentrations, and higher
RER values during the final 20 min of exercise (P<0.05). Markers of physiologic function and sensory perception changed similarly throughout exercise; no differences were
observed among subjects in response to beverage treatments for changes in plasma concentrations of lactate, sodium, potassium,
for changes in plasma volume, plasma osmolality, rectal temperature, heart rate, oxygen uptake, rating of perceived exertion,
or for indices of gastrointestinal distress, perceived thirst, and overall beverage acceptance. Compared to ingestion of a
water placebo, consumption of beverages containing 6% to 10% sucrose resulted in similar physiologic and sensory response,
while ingestion of the 6% sucrose beverage resulted in significantly improved end-exercise performance following only 60 min
of intermittent cycling exercise. 相似文献
3.
The consumption of energy drinks (e.g., containing caffeine and taurine) has increased over the last decade among adolescents and athletes to enhance their cognitive level and improve intellectual and athletic performance. Numerous studies have shown that drinking moderate doses of such drinks produces beneficial effects, as they considerably boost the sporting performance of elite athletes in various sports, including both endurance and explosive events. However, apart from their ergogenic effects, the regular consumption of energy drinks also increases blood pressure and consequently incites problems such as hypertension, tachycardia, and nervousness, all of which can lead to cardiovascular disorders. A potential positive correlation between genetics and the moderate consumption of energy drinks and athletic performance has recently been reported; notwithstanding, a better understanding of the genetic variants involved in metabolism is a key area for future research to optimize the dose of energy drink consumed and obtain the maximal ergogenic effect in elite sports. The aim of this literature review, therefore, is to present the results of recent studies, classifying them according to the differences in the associations between energy drinks and: (i) Athletic performance; (ii) cardiovascular risk factors while practicing sports; and (iii) genetic associations and future prospects between the consumption of energy drinks and performance. 相似文献
4.
Energy drinks containing significant quantities of caffeine, taurine and sugar are increasingly consumed, particularly by adolescents and young adults. The putative effects of chronic ingestion of either standard energy drink, MotherTM (ED), or its sugar-free formulation (sfED) on metabolic syndrome were determined in wild-type C57BL/6J mice, in comparison to a soft drink, Coca-Cola (SD), a Western-styled diet enriched in saturated fatty acids (SFA), and a combination of SFA + ED. Following 13 weeks of intervention, mice treated with ED were hyperglycaemic and hypertriglyceridaemic, indicating higher triglyceride glucose index, which was similar to the mice maintained on SD. Surprisingly, the mice maintained on sfED also showed signs of insulin resistance with hyperglycaemia, hypertriglyceridaemia, and greater triglyceride glucose index, comparable to the ED group mice. In addition, the ED mice had greater adiposity primarily due to the increase in white adipose tissue, although the body weight was comparable to the control mice receiving only water. The mice maintained on SFA diet exhibited significantly greater weight gain, body fat, cholesterol and insulin, whilst blood glucose and triglyceride concentrations remained comparable to the control mice. Collectively, these data suggest that the consumption of both standard and sugar-free forms of energy drinks induces metabolic syndrome, particularly insulin resistance. 相似文献
5.
Helmut Schrder Vanessa Cruz Muoz Marta Urquizu Rovira Victoria Valls Ibaez Josep-Maria Manresa Domínguez Gerard Ruiz Blanco Monserrat Urquizu Rovira Pere Toran Monserrat 《Nutrients》2021,13(6)
Increasing sugar-sweetened beverages (SSB) consumption and associated health impacts warrant health-policy action. We assessed associations of socioeconomic and lifestyle variables with adolescents’ consumption of regular soda (RSD), sport (SD), and energy (ED) drinks. Cross-sectional study of 3930 Spanish adolescents (2089 girls, 1841 boys) aged 13–18 years). We compared frequency of consuming each SSB type (European Food Safety Authority questionnaire) with sociodemographic and lifestyle variables (standardized questions). RSD, SD, and ED were consumed at least weekly by 72.7%, 32.3%, and 12.3% of participants, respectively, and more frequently (p < 0.001) by boys, compared to girls. Multivariate ordinal logistic regression showed inverse association between RSD, SD, and ED consumption and parental occupation-based socioeconomic status (p < 0.01). Daily smoking was associated (p < 0.001) with higher ED (OR 3.64, 95% CI 2.39–5.55) and RSD (OR 2.15, 95% CI 1.56–2.97) consumptions. SD intake was associated inversely with smoking (OR 0.60, 95% CI 0.40–0.89, p = 0.012) and directly with physical activity (OR 2.93, 95% CI 2.18–3.95, p < 0.001). School performance was lower among ED (OR 2.14, 95% CI, 1.37–3.35, p = 0.001) and RSD (OR 1.81, 95% CI 1.24–2.64, p = 0.002) consumers, compared to SD. Maleness and low socioeconomic status predicted SSB consumption. Smoking and low school performance were associated with higher ED and RSD intakes. 相似文献
6.
Sylvie Mrug LaRita C. Jones Marc N. Elliott Susan R. Tortolero Melissa F. Peskin Mark A. Schuster 《The Journal of adolescent health》2021,68(1):155-160
PurposePrevious studies showed associations between soft drink consumption and mental health problems in adolescents, but the direction of these effects is unknown. This study examines the hypotheses that soft drink consumption predicts aggression and depressive symptoms over time and that these mental health problems predict soft drink consumption.MethodsInterviews were conducted with 5,147 children and their caregivers from three sites at child ages 11, 13, and 16. At each time point, youth reported on their frequency of consuming soft drinks, aggressive behavior, and depressive symptoms. An autoregressive cross-lagged path model tested reciprocal relationships between soft drink consumption, aggressive behavior, and depressive symptoms over time.ResultsMore frequent consumption of soft drinks was associated with more aggressive behavior at each time point and depressive symptoms at ages 11 and 13 (r = .04 to .18, p ≤ .002). After adjusting for covariates and stability of each behavior over time, soft drink consumption at ages 11 and 13 predicted more aggressive behavior at the next time point (β = .08 and .06, p < .001). Aggressive behavior at age 13 also predicted more soft drink consumption at age 16 (β = .06, p = .002). Soft drink consumption at age 13 predicted fewer depressive symptoms (β = ?.04, p = .007), but depressive symptoms did not predict soft drink consumption.ConclusionsMore frequent consumption of soft drinks may contribute to aggressive behavior in adolescents over time; there is some support for reciprocal relationships. There is no evidence for soft drink consumption contributing to adolescents' depression. Future research should examine longitudinal effects over shorter intervals. 相似文献
7.
(1) Background: In 2020, there seems to have been a global shift in lifestyle and eating habits with the emergence of the coronavirus disease 2019 (COVID-19) and the ensuing lockdowns implemented by national governments. This study assessed the impact of the COVID-19 lockdown on SSBs consumption among healthy 6–11 years old children in Saudi Arabia; (2) Methods: This is a mixed-methods study, incorporating a quantitative component, which was a validated Arabic online questionnaire completed by parents, and a qualitative component, involving structured interviews with 10 selected parents using a criterion sampling method; (3) Results: There was a small decrease in consumption reported during lockdown across all SSBs types (soft drinks, n = 58 (13.9%); juices: n = 115 (27.6%); flavored milk: n = 93 (22.3%)). The results showed that with every increase in the dental pain scale there was a positive odd (AOR:0.64; p = 0.001) of decreased consumption of SSBs. Several themes related to increase and decrease SSBs consumption emerged; (4) Conclusions: There was a small decrease in SSBs consumption during lockdown reported by parents. Several themes emerged that can be used to strategize against problematic eating behavior, enabling such provisions as family dietary interventions, which target both parents and children. 相似文献
8.
9.
目的研究平调饮对小鼠S180肉瘤抑瘤效应及免疫功能的影响,及对H22肝癌小鼠生命延长作用,为平调饮的临床应用提供实验依据。方法取雄性昆明小鼠,(对S180实验取75只,对H22实验取50只),体重:18±2g,随机各等分为5组,造模第2天开始给药。对S180小鼠,实验结束后第2天处死,称其体重、脾脏、胸腺及移植瘤重量,计算抑瘤率、脾脏指数、胸腺指数;对H22小鼠,观察生存时间,计算生命延长率。结果①平调饮各组对S180肉瘤小鼠的抑瘤率均显著高于模型组(P<0.05);②平调饮各组与模型组及5-Fu治疗组相比较,可使胸腺指数、脾脏指数明显升高(P<0.01);③对H22小鼠生存时间亦明显长于模型组和5-Fu治疗组(P<0.01)。结论平调饮对小鼠S180肉瘤有较强的抑瘤作用,并能显著提高机体免疫功能,还可以延长H22肝癌小鼠生存时间,这是一值得进一步研究的临床课题。 相似文献
10.
Cecile A Marczinski 《Advances in nutrition (Bethesda, Md.)》2015,6(1):96-101
Energy drinks, the fastest growing segment in the beverage market, have become popular mixers with alcohol. The emerging research examining the use of alcohol mixed with energy drinks (AmEDs) indicates that the combination of caffeine-containing energy drinks with alcohol may be riskier than the use of alcohol alone. The public health concerns arising from AmED use are documented in different research domains. Epidemiologic studies reveal that the consumption of AmEDs is frequent among young and underage drinkers, demographic groups that are more likely to experience the harms and hazards associated with alcohol use. In addition, for all consumers, elevated rates of binge drinking and risk of alcohol dependence have been associated with AmED use when compared to alcohol alone. Results from laboratory studies help explain why AmED use is associated with excessive intake of alcohol. When an energy drink (or caffeine) is combined with alcohol, the desire (or urge) to drink more alcohol is more pronounced in both humans and animals than with the same dose of alcohol alone. The experience of drinking alcohol appears to be more rewarding when combined with energy drinks. Given that caffeine in other foods and beverages increases preference for those products, further research on AmEDs may elucidate the underlying mechanisms that contribute to alcohol dependence. 相似文献