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991.
Stewart G. Trost Alison L. Marshall Ruth Miller Jane T. Hurley Julian A. Hunt 《Journal of Science and Medicine in Sport》2007,10(6):428-435
The purpose of this study was to evaluate the concurrent validity of a modified version of the widely used previous day physical activity recall (PDPAR-24) self-report instrument in a diverse sample of Australian adolescents comprising Aboriginal and Torres Strait Islanders (A&TSI) and non-indigenous high school students. A sample of 63 A&TSI and 59 non-indigenous high school students (N = 122) from five public secondary schools participated in the study. Participants completed the PDPAR-24 after wearing a sealed electronic pedometer on the previous day. Significant positive correlations were observed between the self-reported physical activity variables (mean MET level, blocks of vigorous activity, and blocks of moderate-to-vigorous physical activity) and 24-h step counts. Validity coefficients (rho) ranged from 0.29 to 0.34 (p < 0.05). A significant inverse correlation was observed for self-reported screen time and 24-h step count (rho = −0.19, p < 0.05). Correlations for A&TSI students were equal to or greater than those observed for non-indigenous students. The PDPAR-24 instrument is a quick, unobtrusive, and cost-effective assessment tool that would be useful for evaluating physical activity and sedentary behaviour in population-based studies. 相似文献
992.
This trial set out to test the hypothesis that there is no difference in the incidence of intra-abdominal adhesions after a stereotyped intraperitoneal injury created via laparoscopy or laparotomy. Twenty New Zealand White rabbits had a 2 × 2 cm area of peritoneum stripped off their caecum and adjacent parietal peritoneum, either by laparotomy or laparoscopy. Outcome was assessed by the incidence of adhesions to the test site and the wound. There was no difference in the rate of adhesions at the test site in the two groups. The rate of adhesions to the wound was different in the two groups (70% laparotomy, 0% laparoscopy; P = 0.003). In a rabbit model, comparing laparoscopy and laparotomy in a strictly controlled operative environment, a stereotyped intraperitoneal injury results in similar rates of postoperative adhesions. Laparoscopy is, however. associated with a much lower incidence of wound adhesion. The potential for postoperative adhesions is real after laparoscopic surgery. 相似文献
993.
本实验采用性腺摘除或经假摘除手术的两性SD大鼠,其中部分动物分别予以睾酮(T)或雌二醇(E_2),观察它们在急性饥饿或非饥饿状态下血清T_4、TSH与T浓度变化。结果提示急性饥饿可使雄鼠甲状腺合成或分泌T_4和性腺分泌睾酮减少,从而不完全地抑制了雄激素所介导的对垂体TSH分泌的兴奋作用。外源性T替代虽然可以使去势雄鼠血清T浓度恢复正常,但却无兴奋TSH分泌的作用;饥饿组去势雄鼠接受外源性T后血清TSH更为减少。提示外源性T可抑制此组雄鼠垂体TSH合成及(或)释放。 相似文献
994.
BackgroundSever's disease, is a musculoskeletal condition occurring in adolescence that symptomatically manifests as posterior heel pain during ambulation. Often participation in physical activity is severely limited resulting in frustration for children and parents alike. Conservative treatment options have included rest, abstinence from athletic activity, heel lifts, foot orthotic devices, ice, and calf-stretching exercise. The authors are proposing arch taping as an additional viable treatment option for controlling heel pain during athletic and other weight-bearing activities in patients with Sever's disease.ObjectiveTo assess the immediate impact of arch taping in controlling heel pain during ambulation in a group of subjects with Sever's disease and to discuss possible biomechanical explanations.Methods and measuresEleven subjects diagnosed with Sever's disease with a history of posterior heel pain were evaluated and treated by three different therapists in three different regions in the USA. Level of perceived pain during ambulation was reported before and immediately after arch tape application. The Wilcoxon Signed Ranks Test was utilized to assess pain reduction with significance set at p < 0.05 level and effect size was determined with Cliff's delta statistic.OutcomesEach subject reported an immediate reduction in heel pain during ambulation with arch taping. The median reduction in pain was 5 levels. Wilcoxon's statistic was significant with p = 0.001 and Cliff's delta revealed a value of 0.97 indicating a large pain reduction effect with arch taping.ConclusionsThe arch taping technique applied in this case series was effective in the immediate reduction of posterior heel pain during ambulation and allowed an early return to sports activities for those involved in athletics. This technique could be considered an additional treatment option for others with similar clinical presentations. Possible biomechanical explanations may relate to a windlass effect provided through the taping technique. 相似文献
995.
996.
EDWARD B. DIETHRICH M.D. DIOGO IVENS FERRAZ. DA CUNHA E SA M.D. ILHAN. BAHADIR M.D. OSVALDO. SANTIAGO M.D. 《Journal of interventional cardiology》1990,3(3):145-156
The proliferation of sophisticated endovascular interventions is mandating more definitive and comprehensive documentation of atherosclerotic lesions and the results of the interventional devices used in their removal. A technique with a potential to fulfill these goals, intravascular ultrasound imaging (IVUS), was evaluated against pressure gradients, arteriography, and femoral-radial indices in 11 patients with stenotic iliac lesions. The two-dimensional, real-time scans were useful in measuring pre-and posttreatment cross-sectional diameters and luminal areas for procedural assessment. Furthermore, the ultrasound scans clearly identified arterial wall calcifications, iliac veins, soft plague formations, dissections, synthetic graft anastomoses, and intravascular stents, often with definition superior to arteriography. The IVUS technique was useful in selecting interventional therapies, in particular, the need for stent implantation to control intimal flaps. Further, IVUS demonstrated its ability as a substitute for contrast arteriography in a twelfth patient with an iliac stent in whom a protocol-dictated follow-up arteriogram was contraindicated. 相似文献
997.
998.
The authors present two cases of percutaneous cecostomy performed with a modified approach previously described for percutaneous gastrostomy and cholecystostomy. T-fastener devices were used to affix the cecum to the anterior abdominal wall; thus, the potential problem of fecal spillage was prevented. In both cases, adequate fecal drainage was provided without complication. 相似文献
999.
Assault by burning is an often unappreciated cause of burn injury. One hundred forty-eight of 3678 adults admitted to a major burn center with acute burn injuries sustained their burns as a result of an assault by another adult. High-risk groups included blacks and alcohol abusers. Patients were extremely reductant to describe the cause of their injury and to identify their assailant. In contrast to child abuse, very few cases go to court due to the patient's failure to press charges. There was no typical burn pattern, although the injury often did not coincide with the initial medical history. The presence of multiple trauma, occurring in 16% of these patients, must be excluded in the assaulted patient. 相似文献
1000.
Exposure to N-methyl-D-aspartate increases release of arachidonic acid in primary cultures of rat hippocampal neurons and not in astrocytes 总被引:4,自引:0,他引:4
The release of [3H]arachidonic acid (ARA) was investigated from prelabelled primary cultures of hippocampal neurons and astroglial cells. The activation of N-methyl-D-aspartate (NMDA) subtype of glutamate receptors resulted in a dose-dependent stimulation of [3H]ARA release. The half maximal effect was obtained at about 15 microM NMDA, whereas the maximum concentration (50 microM NMDA) produced about a 2-fold increase in 7-day-old cultures. This elevation in [3H]ARA release was blocked in a dose-related manner by the NMDA receptor antagonist, 2-amino-5-phosphonovaleric acid (APV), and by Mg2+ which blocks NMDA receptor-linked Ca2+ ion channels. The removal of external Ca2+ inhibited NMDA-induced release, whereas treatment with calcimycin (A 23187, a Ca2+ ionophore) greatly increased the [3H]ARA release. The inhibitors of phospholipase A2, nordihydroguaiaretic acid and mepacrine, decreased the NMDA-dependent [3H]ARA release in a dose-related manner, maximum inhibition reaching to about 90% at high doses. Entry of Ca2+ brought about by opening the voltage-sensitive channels by high K+ had no effect on the release of [3H]ARA, indicating that NMDA gated channels are situated in a part of the neuron where Ca2+ entry through this route is more efficiently coupled to the activation of phospholipase A2. Treatment with NMDA had no significant effect on [3H]ARA release in hippocampal astroglial cells as opposed to neurons. This was not due to inability of astrocytes to release ARA, for ATP still evoked [3H]ARA release, and this was markedly inhibited by mepacrine. It is suggested that ARA act as both intracellular and intercellular messengers in the functioning of NMDA receptors in synaptic transmission and plasticity in the hippocampus. 相似文献