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1.
PurposeAlthough many studies have examined the efficiency of various protective devices for reducing the dose of radiation exposure to physicians during interventional pain procedures, no study has compared the protective effect of these devices when they are used in combination. The purpose of this prospective experimental study was to determine the best combination of radiation-shielding devices.Materials and MethodsUsing anthropomorphic phantoms of a physician and patient, we measured the radiation protection efficiency (RPE) of each of the following protection methods and in combination during C-arm–guided simulated lumbar epidural injection: (a) personal protective equipment (PPE), (b) bedside curtain shield (Curtain), (c) x-ray tube filter (Filter), and (d) fluoroscopic collimation method (Collimation). We measured exposure doses using personal electronic dosimeters at the eye, thyroid, and gonad levels for 1 minute. Each experiment was repeated 15 times.ResultsThe radiation exposure dose and RPE with the best single-, double-, and triple-protection methods were as follows: PPE for the single-protection method (11.82 μSv/min, 80.04%), PPE + Collimation for the double-combination method (4.68 μSv/min, 92.09%), and PPE + Collimation + Curtain for the triple-combination method (3.08 μSv/min, 93.39%). Additionally, PPE + Collimation + Curtain + Filter for the quadruple-combination method resulted in a radiation exposure and RPE of 2.91 μSv/min and 93.61%, respectively, compared with nonprotection.ConclusionsThe best single-, double-, and triple-protection method was PPE, PPE + Collimation, and PPE + Collimation + Curtain, respectively. While preparing protective equipment, we recommend prioritizing equipment in this order.  相似文献   
2.
BackgroundFoam Rolling (FR) is currently used by athletes at all levels. It is not known whether FR is more effective being used as a warm up to aid performance or more effectively used as a cool-down for recovery. Therefore, the purpose of this systematic review was to determine the effects of FR on performance and recovery.MethodsA customized search strategy was conducted to search seven electronic databases: Google Scholar; Science Direct; Pubmed Central; Pubmed; ISI Web of Science; Medline and Scopus. The database search was limited to journals published in English between January 2006 and June 2019. Any study design, for example, cross-over, repeated measures, randomized-control trials, was considered, as long as one of the interventions was using a FR. Studies that tested FR combined with other techniques were also considered, as long as one of the conditions was FR only.ResultsA total of 49 articles met the inclusion criteria.ConclusionFR may reduce muscle stiffness and increase ROM and should be used in combination with dynamic stretching and active warm-up before a training session. Furthermore, the optimum dosage to achieve these flexibility benefits seems to be a total 90s–120s of FR. FR reduced DOMS and increased PPT, and therefore may optimize recovery from training. Future studies on the effects of FR should include true controls or sham groups, and consider the FR experience of the athlete.Systematic Review RegistrationPROSPERO – CRD42017064976.  相似文献   
3.
Background:Stretching has been proven to be effective on pain and range of motion (ROM) in patients with plantar fasciitis. Despite recent gain in popularity and the proposed theories of effectiveness of foam roller, there is a lack of literature on the effect of foam rolling on plantar fasciitis.Objective:The objective of this study was to compare the effects of foam rolling and stretching on pain and ankle ROM in patients with plantar fasciitis.Methods:A total of 50 participants were included and randomly allocated to the stretching and foam roller groups. Visual analog scale (VAS), pressure pain thresholds (PPTs) for gastrocnemius, soleus and plantar fascia and weight-bearing lunge test (WBLT) measurements were recorded at baseline and immediately after treatment.Results:Within-group analysis has shown there is a statistically significant difference (p<0.001) in all the outcome measures in both foam roller and self-stretching groups. The between-groups analysis showed no statistical significance difference in VAS, plantar fascia PPT and WBLT parameters (with p-values of 0.171, 0.372 and 0.861, respectively); however, significant differences were found in gastrocnemius PPT (p=0.029) and soleus PPT (p=0.013).Conclusion:It was seen that both stretching and foam rolling techniques helped in reducing pain and increasing the ROM. However, the effectiveness of foam roller was superior to stretching in terms of increase in PPTs at gastrocnemius and soleus.Clinical Trial Registration No:CTRI/2018/01/011398.Name of registry:The Clinical Trials Registry — India (CTRI); https://ctri.nic.in.  相似文献   
4.
P-selectin glycoprotein ligand 1 (PSGL-1) is a mucin-like selectin counterreceptor that binds to P-selectin, E-selectin, and L-selectin. To determine its physiological role in cell adhesion as a mediator of leukocyte rolling and migration during inflammation, we prepared mice genetically deficient in PSGL-1 by targeted disruption of the PSGL-1 gene. The homozygous PSGL-1-deficient mouse was viable and fertile. The blood neutrophil count was modestly elevated. There was no evidence of spontaneous development of skin ulcerations or infections. Leukocyte infiltration in the chemical peritonitis model was significantly delayed. Leukocyte rolling in vivo, studied by intravital microscopy in postcapillary venules of the cremaster muscle, was markedly decreased 30 min after trauma in the PSGL-1-deficient mouse. In contrast, leukocyte rolling 2 h after tumor necrosis factor alpha stimulation was only modestly reduced, but blocking antibodies to E-selectin infused into the PSGL-1-deficient mouse almost completely eliminated leukocyte rolling. These results indicate that PSGL-1 is required for the early inflammatory responses but not for E-selectin-mediated responses. These kinetics are consistent with a model in which PSGL-1 is the predominant neutrophil P-selectin ligand but is not a required counterreceptor for E-selectin under in vivo physiological conditions.  相似文献   
5.
目的观察小鱼际滚法对组织机化期骨骼肌钝性损伤家兔纤连蛋白-1(fibronectin-1,FN-1)、结缔组织生长因子-1(connective tissue growth factor,CTGF-1)表达的影响。方法选取30只成年新西兰大耳白兔,随机均分为手法治疗组、模型对照组、空白对照组,各10只。手法治疗组予造模、治疗处理,模型对照组予造模、不治疗处理,空白对照组予不造模、不治疗处理,采取自制重力铅锤击打兔右后下肢股四头肌造成骨骼肌钝性损伤模型,并在疗程3 d后3组全处死,在兔股四头肌受损区域内取肌肉组织,HE染色观察组织形态的变化,Western-Blot检测治疗前后FN-1、CTGF-1的变化情况。结果HE染色结果显示:模型对照组与空白对照组对比,其模型对照组肌纤维受损较多,并有不规则结缔样组织填充其中;手法治疗组与模型对照组对比,手法治疗组新生的肌纤维及新生血管更明显,炎性细胞较少,肌肉形态受损较轻。Western-Blot结果显示:模型对照组FN-1、CTGF-1指标显著高于空白对照组,手法治疗组FN-1、CTGF-1指标均显著高于空白对照组、低于模型对照组,差异均有统计学意义(P<0.05)。结论在组织机化期骨骼肌钝性损伤模型家兔股四头肌修复过程中,运用小鱼际滚法治疗,可有助修复受损的骨骼肌,使炎性细胞减少,促进骨骼肌新生,改善家兔运动功能,提高疗效,值得推广应用。  相似文献   
6.
目的探讨岩斜区幕上下锁孔入路显微解剖,为岩斜区手术入路提供解剖学依据。方法在10例国人成人头颅湿标本上,在手术显微镜下观察,测量幕上下锁孔入路的重要显微结构;对手术前后共10例标本进行3D-CT颅骨重建:并对重要结构进行测量。结果通过幕上下锁孔入路,可涉及的重要解剖区域包括三叉神经、面听神经、岩骨内部结构、脑干腹侧间隙等,重要参数包括岩骨嵴磨除范围。结论岩斜区幕上下锁孔入路是手术治疗岩斜区肿瘤的灵活运用的手术入路。  相似文献   
7.
Conventional range hoods cannot effectively prevent the oil fumes containing cooking-induced harmful material from escaping into the kitchen Air curtains and guide plates have been used in range hoods to reduce the escape of airborne emissions and heat, thereby improving the kitchen environment and the cook's degree of comfort. In this article, numerical simulations are used to study the effects of the jet velocity of an air curtain, the jet angle of the air curtain, the width of the jet slot, the area of the guide plate, and the exhaust rate of the range hood on the perceived temperature, the perceived concentration of oil fumes, the release temperature of oil fumes, and the concentration of escaped oil fumes in a kitchen. The orthogonal experiment results show that the exhaust rate of the range hood is the main factor influencing the fumes concentration and the temperature distribution in the kitchen. For the range hood examined in the present study, the optimum values of the exhaust rate, the jet velocity of the air curtain, the jet angle of the air curtain, the width of the jet slot, and the area of the guide plate are 10.5 m3/min, 1.5 m/s, ?5°, 4 mm, and 0.22 m2, respectively, based on the results of the parametric study. In addition, the velocity field, temperature field, and oil fumes concentration field in the kitchen using the proposed range hood with the air curtain and guide plate are analyzed for those parameters. The study's results provide significant information needed for improving the kitchen environment.  相似文献   
8.
结合浙江省松阳县垃圾填埋场设计实例,介绍山谷型非标准填埋场防渗改造及扩建中新旧填埋区的隔离及已填埋区的防渗改造做法.  相似文献   
9.
New-generation oxide dispersion-strengthened (ODS) alloys with a high volume fraction of nano-oxides of 5% are intended to become the leading creep- and oxidation-resistant alloys for applications at 1100–1300 °C. Hot consolidation of mechanically alloyed powders by intensive plastic deformation followed by heat treatment of the alloys are the key aspects for achieving top creep properties, typically ensured by a coarse-grained microstructure strengthened with homogeneously dispersed, very stable yttrium nano-oxides. The rotary swaging method proves to be favourable for hot consolidation of the new-generation ODS alloy presented. Compared to specimens consolidated by hot rolling, consolidation by hot rotary swaging predetermines the formation of coarse grains with a very high aspect ratio during subsequent secondary recrystallization. Such a grain morphology increases the creep strength of the new-generation ODS alloy considerably.  相似文献   
10.
Background: Gross motor development is usually assessed in terms of age of achievement of motor milestones. Although there is generally an impression of faster development if the milestones are achieved at younger ages, no longitudinal studies have been done on the associations between the milestones, especially in Japan. As a part of the Japan Children's Study, the purpose of the present study was to determine whether the achievement of gross motor milestones in infancy is related with the age of walking. Methods: This was a prospective cohort study of 290 healthy and term infants born in a district of Osaka City, Japan. Three milestones (rolling over, sitting, and crawling) were observed in the laboratory for infants aged at 4 and 9 months by a pediatrician and a developmental psychologist, and the age of walking was confirmed in questionnaires filled in by the parents at 18 and 27 months. Results: Children who could roll over at 4 months, and sit and crawl at 9 months, walked earlier than children who could not roll over, sit and crawl, respectively. With regard to crawling, children who were creeping had a 1 month delay in walking, and those who could not move forward had a 2 month delay compared to typical crawlers. On multiple regression analysis these three milestones were positively associated with walking: rolling over (β= 0.567), sitting (β= 1.973) and crawling (β= 1.473). Conclusion: The age and the patterns of sitting, crawling and rolling over were all related to the age of independent walking among Japanese infants. Consideration of milestone definition and variations is essential in medical check‐up.  相似文献   
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