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41.
OBJECTIVE: To compare effectiveness of two techniques for removing football face masks: cutting loop straps [cutting tool: FMXtractor (FMX)] or removing screws with a cordless screwdriver and using the FMXtractor as needed for failed removals [combined tool (CT)]. Null hypotheses: no differences in face mask removal success, removal time or difficulty between techniques or helmet characteristics. DESIGN: Retrospective, cross-sectional. SETTING: NOCSAE-certified helmet reconditioning plants. PARTICIPANTS: 600 used high school helmets. INTERVENTIONS: Face mask removal attempted with two techniques. MAIN OUTCOME MEASUREMENTS: Success, removal time, rating of perceived exertion (RPE). RESULTS: Both techniques were effective [CT 100% (300/300); FMX 99.4% (298/300)]. Use of the backup FMXtractor in CT trials was required in 19% of trials. There was significantly (P<0.001) less call for the backup tool in helmets with silver screws (6%) than in helmets with other screws (31%). Mean removal time was 44.51+/-18.79s (CT: 37.84+/-15.37s, FMX: 51.21+/-19.54s; P<0.001). RPE was different between techniques (CT: 1.83+/-1.20, FMX: 3.11+/-1.27; P<0.001). Removal from helmets with silver screws was faster (Silver=33.38+/-11.03, Others=42.18+/-17.64; P<0.001) and easier (Silver=1.42+/-0.89, Other=2.23+/-1.33; P<0.001). CONCLUSIONS: CT was faster and easier than FMX. Most CT trials were completed with the screwdriver alone; helmets with silver screws had 94% screwdriver success. Clinically, these findings are important because this and other research shows that compared to removal with cutting tools, screwdriver removal decreases time, difficulty and helmet movement (reducing potential for iatrogenic injury). The combined-tool approach captures benefits of the screwdriver while offering a contingency for screw removal failure. Teams should use degradation-resistant screws. CLINICAL RELEVANCE: Sports medicine professionals must be prepared with appropriate tools and techniques to efficiently remove the face mask from an injured football player's helmet.  相似文献   
42.
Inhalation anesthetics are effective chemical preconditioning agents in experimental cerebral ischemia. However, previous work has been performed exclusively in male animals. We determined if there is a gender difference in ischemic outcome after isoflurane preconditioning (IsoPC), and if this sex-specific response is linked to differences in Akt phosphorylation or expression of neuronal inducible cell-death putative kinase (NIPK), a negative modulator of Akt activation. Young and middle-aged male and female mice were preconditioned for 4 h with air (sham PC) or 1.0% IsoPC and recovered for 24 h. Cortices were subdissected from preconditioned young male and female mice for measurement of Akt phosphorylation (Western blot) and NIPK mRNA (quantitative polymerase chain reaction). Additional cohorts underwent 2 h of reversible middle cerebral artery occlusion. Lastly, male and female Akt1(+/+) and Akt1(-/-) mice were studied to determine if gender differences in ischemic outcome after IsoPC is Akt1-dependent. Infarction volume was determined at 22 h reperfusion (2,3,5-triphenyltetrazolium chloride). As expected, IsoPC decreased ischemic damage as compared with sham PC in young and middle-aged male mice. In contrast, IsoPC markedly increased infarction in young female mice and had no effect in middle-aged female mice. Cortical phospho-Akt was increased by IsoPC versus sham PC only in male mice. No increase was observed in IsoPC female mice. NIPK mRNA was higher in female mice than in male mice regardless of preconditioning status. Male IsoPC neuroprotection was lost in Akt1-deficient male mice. We conclude that IsoPC is beneficial only in ischemic male brain and that sex differences in IsoPC are mediated through Akt activation and basal NIPK expression.  相似文献   
43.
OBJECTIVES: Oral appliances are designed to treat snoring and sleep apnea by advancing the mandible and tongue. We test the hypothesis that an oral appliance affects palatal snoring as well as tongue base obstruction. METHODS: Prospective observational cohort study. Sixty patients with a chief complaint of snoring with or without apnea were enrolled. Each patient underwent a home sleep test followed by 3 weeks sleeping with an oral appliance. Each patient then underwent a repeat home sleep test while using the device. RESULTS: There was a statistically significant improvement in the snores per hour (P = 0.0005), the maximum snoring loudness (P = 0.0001), average snoring loudness (P = 0.00001), and the percentage of palatal snoring (P = 0.0007). There was also a significant decrease in oxygen desaturation events (P = 0.003). CONCLUSIONS: This study suggests oral appliances may be effective treatment for both palatal and tongue base snoring.  相似文献   
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The infective third-stage larvae of the hookworms Necator americanus and Ancylostoma duodenale infect their human hosts by active skin invasion, but A. duodenale is in addition capable of oral infection. The behaviour of the larvae when crawling on surfaces has already been described. Here we analyse in various in vitro systems the other behavioural invasion phases: activation, penetration, and orientation within the host. The larvae normally remained in a motionless, energy-saving, resting posture. An activation to sinusoidal locomotion was stimulated in both species by similar cues such as touch, vibration, water currents, heat, light, and chemicals. Human breath in addition stimulated searching and waving (nictating) behaviour, which facilitates a change-over to the host. Activating cues in air streams were warmth and moisture; CO2 activated only in combination with warmth and/or moisture. Penetration behaviour in both species was stimulated by warmth and skin extracts. The stimulating components of skin extracts were fatty acids, but their stimulating characteristics differed from those inducing schistosome cercarial skin penetration. After penetration into agar substrates, both species showed thermo-orientation, but only A. duodenale followed gradients of serum. The directing serum cues were not amino acids and glucose (the supposed cues for schistosome blood vessel localization), but Ringers solution attracted the larvae. The host-finding and host-invasion behaviour of both hookworm species is well adapted to the invasion of the human skin, and there seems to be no particular adaptation of A. duodenale behaviour to the oral infection mode. Hookworm host-finding behaviour is not as complex as that of schistosome cercariae but seems well adapted to the ecological conditions in the transmission sites.  相似文献   
47.
Recently developed PCR systems offer online-monitoring of amplification and allow simple and reliable DNA quantification. We have used the LightCycler system to develop a simple and rapid method for direct identification of female carriers of deletions and duplications in the dystrophin gene. The challenge resides in the ability to identify the presence of a deleted or duplicated allele over the background contributed by the normal allele. Quantification is based on the determination of the ratio between potentially deleted/duplicated dystrophin exons and non-deleted/-duplicated reference exons using the unspecific dsDNA-dye SYBRgreen I. In a retrospective study, we evaluated our method in female relatives of DMD/BMD patients with known carrier status by comparative analysis of deleted or duplicated versus non-deleted/-duplicated exons. Carrier status was accurately attributed in 100% of cases, the mean ratios being 0.52+/-0.12 for deletion carriers (expected value: 0.5) and 1.56+/-0.18 for duplication carriers (expected value: 1.5) vs. 1.022+/-0.17 for non-carriers (expected value: 1.0). The method proved to be simple, rapid, reliable, and cost-effective. It may be used for direct determination of deletions/duplications in potential DMD/BMD carriers and may easily be adapted for other genetic conditions involving deletions and duplications.  相似文献   
48.
Psychological features and complaints of persons presenting to medical settings with heart-focused anxiety and noncardiac chest pain are poorly understood. Comparing 20 healthy heart-anxious patients to cardiac and surgical inpatients and nonpatient controls, we found that healthy heart-anxious patients (a) were as afraid of chest pain and heart palpitations as inpatients with heart disease, (b) were as incapacitated by symptoms and using medical services as much as both inpatient groups; and (c) reported higher levels of cardiac disease conviction, heart awareness, and behaviors designed to protect their heart than surgical patients and nonpatients. Compared to all other groups, healthy heart-anxious patients reported more panic and other anxiety disorders, hypochondriacal beliefs, physical symptoms, obsessive-compulsive concerns, and negative affect. Following a hyperventilation test, heart-anxious patients also indicated more distressing symptoms and thoughts, and felt less safe and in control than surgical patients and nonpatients. Results support efforts for a timely recognition, diagnosis, and behavioral treatment of persons with heart-focused anxiety.  相似文献   
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Longitudinal data were used to investigate whether anxiety, depressive, disruptive, personality, or substance use disorders are associated with risk for the development of eating disorders during adolescence or early adulthood. Psychiatric disorders were assessed among 726 youths from a random community sample during adolescence and early adulthood. Depressive disorders during early adolescence were associated with elevated risk for the onset of eating disorders, dietary restriction, purging behavior, and recurrent weight fluctuations after preexisting eating problems and other psychiatric disorders were controlled statistically. Disruptive and personality disorders were independently associated with elevated risk for specific eating or weight problems. The present findings suggest that depressive disorders during early adolescence may contribute to the development of eating disorders during middle adolescence or early adulthood.  相似文献   
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