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91.
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Context:
Practice guidelines recommend a multifaceted approach for managing concussions, but a relatively small percentage of athletic trainers (ATs) follow these recommendations. Understanding ATs'' beliefs toward the recommended concussion practice guidelines is the first step in identifying interventions that could increase compliance. The theory of planned behavior (TPB) allows us to measure ATs'' beliefs toward the recommended concussion practice guidelines.Objective:
To examine the influence of ATs'' beliefs toward the current recommended concussion guidelines on concussion-management practice through an application of the TPB.Design:
Cross-sectional study.Setting:
A Web link with a survey was e-mailed to 1000 randomly selected members of the National Athletic Trainers'' Association (NATA).Patients or Other Participants:
A total of 221 certified ATs working in secondary school/clinic, high school, and college/university settings.Main Outcome Measure(s):
A 66-item survey reflecting the current recommended concussion guidelines of the NATA and International Conference on Concussion in Sport was created to measure beliefs using the TPB constructs attitude toward the behavior (BA), subjective norms (SN), perceived behavioral control (PBC), and behavioral intention (BI) of ATs. We used a linear multiple regression to determine if the TPB constructs BA, SN, and PBC predicted BI and if PBC and BI predicted behavior according to the TPB model.Results:
We found that BA, SN, and PBC predicted BI (R = 0.683, R2 = 0.466, F3,202 = 58.78, P < .001). The BA (t202 = 5.53, P < .001) and PBC (t202 = 9.64, P < .001) contributed to the model, whereas SN (t202 = −0.84, P = .402) did not. The PBC and BI predicted behavior (R = 0.661, R2 = 0.437, F2,203 = 78.902, P < .001).Conclusions:
In this sample, the TPB constructs predicted BI and behavior of ATs'' compliance with recommended concussion-management guidelines. The BA and PBC were the most influential constructs, indicating that those with positive attitudes toward concussion-management recommendations are more likely to implement them, and ATs are less likely to implement them when they do not believe they have the power to do so. We theorize that interventions targeting ATs'' attitudes and control perceptions will lead to improved compliance.Key Words: concussion management, traumatic brain injuries, practice guidelinesKey Points
- Using the theory of planned behavior constructs to investigate the application of recommended concussion-management guidelines by athletic trainers, we found that attitudes toward the behavior and perceived behavioral control were most influential.
- Interventions that take into account athletic trainers'' attitudes and perceived control may help to increase compliance with concussion-management guidelines.
93.
Margarita D. Tsiros Alison M. Coates Peter R. C. Howe Paul N. Grimshaw Jeff Walkley Anthony Shield Richard Mallows Andrew P. Hills Masaharu Kagawa Sarah Shultz Jonathan D. Buckley 《European journal of applied physiology》2013,113(6):1415-1422
The purpose of this study was to investigate if obese children have reduced knee extensor (KE) strength and to explore the relationship between adiposity and KE strength. An observational case–control study was conducted in three Australian states, recruiting obese [N = 107 (51 female, 56 male)] and healthy-weight [N = 132 (56 female, 76 male)] 10- to 13-year-old children. Body mass index, body composition (dual energy X-ray absorptiometry), isokinetic/isometric peak KE torques (dynamometry) and physical activity (accelerometry) were assessed. Results revealed that compared with their healthy-weight peers, obese children had higher absolute KE torques (P ≤ 0.005), equivocal KE torques when allometrically normalized for fat-free mass (FFM) (P ≥ 0.448) but lower relative KE torques when allometrically normalized for body mass (P ≤ 0.008). Adjustments for maternal education, income and accelerometry had little impact on group differences, except for isometric KE torques relative to body mass which were no longer significantly lower in obese children (P ≥ 0.013, not significant after controlling for multiple comparisons). Percent body fat was inversely related to KE torques relative to body mass (r = ?0.22 to ?0.35, P ≤ 0.002), irrespective of maternal education, income or accelerometry. In conclusion, while obese children have higher absolute KE strength and FFM, they have less functional KE strength (relative to mass) available for weight-bearing activities than healthy-weight children. The finding that FFM-normalized KE torques did not differ suggests that the intrinsic contractile properties of the KE muscles are unaffected by obesity. Future research is needed to see if deficits in KE strength relative to mass translate into functional limitations in weight-bearing activities. 相似文献
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96.
Herron KL Lofgren IE Sharman M Volek JS Fernandez ML 《Metabolism: clinical and experimental》2004,53(6):823-830
The influence of a high-cholesterol diet on the atherogenicity of the low-density lipoprotein (LDL) particle was examined by measuring LDL peak diameter and composition, LDL susceptibility to oxidation, and the distribution of cholesterol between LDL subclasses. The crossover intervention randomly assigned 27 premenopausal women and 25 men (18 to 50 years) to an egg (640 mg/d additional dietary cholesterol) or placebo (0 mg/d additional dietary cholesterol) diet for 30 days, followed by a 3-week washout period. Subjects were classified as either hyperresponders (>2.5 mg/dL increase in plasma cholesterol for each 100 mg additional dietary cholesterol consumed) or hyporesponders to dietary cholesterol. Sex was found to have a significant effect on 3 of the parameters examined. LDL peak diameter was significantly larger (P <.005) in females (26.78 +/- 0.59 nm, n = 27) as compared with males (26.52 +/- 0.49 nm, n = 25), regardless of response to dietary cholesterol. The LDL particles of the male participants also had a higher number of triglyceride (TG) and cholesteryl ester (CE) molecules (P <.01); however, cholesterol ester transfer protein (CETP) activity was higher in females (P <.05). Response classification also revealed significant differences in the determination of LDL subclasses. Independent of sex, the LDL-1 particle (P <.05), which is considered to be less atherogenic, was predominant in hyperresponders and this finding was associated with increased cholesterol intake (interactive effect, P <.001). In addition, CETP and lecithin: cholesterol acyltransferase (LCAT) activities were higher in hyperresponders during the egg period (interactive effect, P <.05). Sex, response to cholesterol intake, and diet were not found to affect the susceptibility of LDL to oxidation (P > 0.5). Because LDL peak diameter was not decreased and the larger LDL-1 subclass was greater in hyperresponders following egg intake, these data indicate that the consumption of a high-cholesterol diet does not negatively influence the atherogenicity of the LDL particle. 相似文献
97.
Sinisa Vidovic Jeff Elder Prabhakara Medihala John R. Lawrence Bernardo Predicala Haixia Zhang Darren R. Korber 《Antimicrobial agents and chemotherapy》2015,59(6):3317-3328
In this study, we tested the antimicrobial activity of three metal nanoparticles (NPs), ZnO, MgO, and CaO NPs, against Salmonella enterica serovar Enteritidis in liquid medium and on solid surfaces. Out of the three tested metal NPs, ZnO NPs exhibited the most significant antimicrobial effect both in liquid medium and when embedded on solid surfaces. Therefore, we focused on revealing the mechanisms of surface-associated ZnO biocidal activity. Using the global proteome approach, we report that a great majority (79%) of the altered proteins in biofilms formed by Salmonella enterica serovar Enteritidis were downregulated, whereas a much smaller fraction (21%) of proteins were upregulated. Intriguingly, all downregulated proteins were enzymes involved in a wide range of the central metabolic pathways, including translation; amino acid biosynthetic pathways; nucleobase, nucleoside, and nucleotide biosynthetic processes; ATP synthesis-coupled proton transport; the pentose phosphate shunt; and carboxylic acid metabolic processes, indicating that ZnO NPs exert a panmetabolic toxic effect on this prokaryotic organism. In addition to their panmetabolic toxicity, ZnO NPs induced profound changes in cell envelope morphology, imposing additional necrotic effects and triggering the envelope stress response of Salmonella serovar Enteritidis. The envelope stress response effect activated periplasmic chaperones and proteases, transenvelope complexes, and regulators, thereby facilitating protection of this prokaryotic organism against ZnO NPs. 相似文献
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99.
Kevin M. Conley Delmas J. Bolin Peter J. Carek Jeff G. Konin Timothy L. Neal Danielle Violette 《Journal of Athletic Training》2014,49(1):102-120
Objective
To present athletic trainers with recommendations for the content and administration of the preparticipation physical examination (PPE) as well as considerations for determining safe participation in sports and identifying disqualifying conditions.Background
Preparticipation physical examinations have been used routinely for nearly 40 years. However, considerable debate exists as to their efficacy due to the lack of standardization in the process and the lack of conformity in the information that is gathered. With the continuing rise in sports participation at all levels and the growing number of reported cases of sudden death in organized athletics, the sports medicine community should consider adopting a standardized process for conducting the PPE to protect all parties.Recommendations
Recommendations are provided to equip the sports medicine community with the tools necessary to conduct the PPE as effectively and efficiently as possible using available scientific evidence and best practices. In addition, the recommendations will help clinicians identify those conditions that may threaten the health and safety of participants in organized sports, may require further evaluation and intervention, or may result in potential disqualification.Key Words: medical history, family history, sudden cardiac death, concussion, sickle cell trait, diabetes, heat illness, hydrationParticipation in organized US athletics continues to rise. During the 2010–2011 academic year, more than 7.6 million high school students took part in organized interscholastic sports, compared with 7.1 million in 2005–2006.1 Similarly, an additional 444 077 National Collegiate Athletic Association student–athletes participated in intercollegiate athletics in 2010–2011, compared with 393 509 in 2005–2006.2 This growth in participation has led to a concomitant rise in sudden death. Most sudden deaths have been attributed to congenital or acquired cardiovascular malformations involving male football and basketball players.3–5 Other causes of sudden death include heat stroke, cerebral aneurysm, asthma, commotio cordis, and sickle cell trait.4,5 As sports participation continues to increase and catastrophic death in athletes receives more attention, the medical community should consider adopting a standardized preparticipation examination (PPE) instrument that, at a minimum and to the extent possible, sets out to ensure a safe playing environment for all and to identify those conditions that might predispose an athlete to injury or sudden death.For nearly 4 decades, PPE screening has been used routinely in an attempt to identify those conditions that may place an athlete at increased risk and affect safe participation in organized sports. Few would empirically argue the potential benefits of this practice, yet considerable debate exists as to the current efficacy of the PPE, given the significant disparities that presently characterize the examination and the information gathered. Over time, the PPE has become an integral component of athletics and sports medicine programs; however, the lack of standardization in the process has created confusion. In addition, the failure to adequately define the primary objectives of the PPE has led to the consensus that, in its current form, the PPE does not address the ultimate goal of protecting the health and safety of the player.The American Medical Association Group on Science and Technology6 has asserted that every physician has 2 responsibilities to an athlete during the PPE: “(1) to identify those athletes who have medical conditions that place them at substantial risk for injury or sudden death and to disqualify them from participation or ensure they receive adequate medical treatment before participation and (2) to not disqualify athletes unless there is a compelling medical reason.” As the PPE has evolved over the years, it has become increasingly difficult to meet these standards given the many objectives that have been proposed for the screening instrument. Originally, the primary objectives of the PPE were to (1) detect life-threatening or disabling conditions, (2) identify those conditions that predispose the athlete to injury or disability, and (3) address legal and insurance requirements.7,8 Today, however, those entities charged with developing and revising the PPE (eg, state high school athletic associations, medical associations, state education departments, state health departments, legislators)9 often have different missions, and as a result, they have sought to influence the makeup of the PPE to address their specific interests. This has led to the identification of a number of secondary objectives, including but not limited to documenting athletic eligibility, obtaining parental consent for participation and emergency treatment, and improving athlete performance.9 Most notably, the PPE represents the sole source of medical evaluation for 30% to 88% of children and adolescents annually10,11 and an opportunity to identify conditions that, although not necessarily related to or requiring restriction from athletic participation, nonetheless call for additional follow-up.9 Some authors12 have advocated this practice to evaluate the general health of the athlete and to provide an opening to discuss high-risk behaviors, preventive care measures, and nonathletic concerns. Others oppose this view, stating that the PPE “should not be the sole component of health care for athletes”6 and that the PPE can only be effective if the goals remain specific and properly directed toward the demands of sport participation.6,13 相似文献100.