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1.
目的对比动力髋螺钉(dynamic hip screw,DHS)治疗和股骨近端抗旋髓内钉(proximal femoral nail anti-rotation,PFNA)固定治疗老年股骨粗隆间骨折疗效。方法纳入本院收治的45例采用PFNA固定治疗的老年股骨粗隆间骨折患者作为研究组,研究时间为2017年11月-2018年11月;回顾性分析2016年11月-2017年11月在我院采用DHS治疗的45例老年股骨粗隆间骨折患者的临床资料,作为对照组。记录两组的相关手术指标,观察手术并发症情况。结果研究组的手术时间和骨折愈合时间均短于对照组,术中出血量明显少于对照组,术后疼痛VAS评分均明显低于对照组(P<0.05)。对照组的并发症发生率高于研究组(P<0.05)。结论PFNA固定治疗比DHS治疗老年股骨粗隆间骨折更加安全有效,值得临床借鉴和应用。  相似文献   
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目的 研究新型冠状病毒肺炎常态化疫情防控下应急梯队护士的真实体验。提出针对性改善护士的心理状况的方法和建议。方法 于2021年10月选取上海市静安区闸北中心医院应急梯队的护士11名为研究对象,对其进行半结构式面对面谈话,并采用Colaizzi七步分析法进行资料分析。结果 进入应急梯队的护士普遍存在着紧张焦虑,情绪低落,身心疲惫等心理问题。而执行完应急任务后的成就感,社会的认同,多方的理解支持,有利缓解心理压力。结论 通过对新型冠状病毒肺炎常态化疫情防控下应急梯队护士的真实体验的了解,护士普遍存在各种心理问题,需要给予针对性的干预措施,提高应急梯队成员的心理素质和应急能力。  相似文献   
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Dry powder inhalers (DPIs) are gaining popularity for the delivery of drugs. A cost effective and efficient delivery device is necessary. Developing new DPIs by modifying an existing device may be the simplest way to improve the performance of the devices. The aim of this research was to produce a new DPIs using computational fluid dynamics (CFD). The new DPIs took advantages of the Cyclohaler® and the Rotahaler®. We chose a combination of the capsule chamber of the Cyclohaler® and the mouthpiece and grid of the Rotahaler®. Computer-aided design models of the devices were created and evaluated using CFD. Prototype models were created and tested with the DPI dispersion experiments. The proposed model 3 device had a high turbulence with a good degree of deagglomeration in the CFD and the experiment data. The %fine particle fraction (FPF) was around 50% at 60?L/min. The mass median aerodynamic diameter was around 2.8–4?μm. The FPF were strongly correlated to the CFD-predicted turbulence and the mechanical impaction parameters. The drug retention in the capsule was only 5–7%. In summary, a simple modification of the Cyclohaler® and Rotahaler® could produce a better performing inhaler using the CFD-assisted design.  相似文献   
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PurposeTo investigated the effect of vibratory stimulus on masseter muscles during oral fine motor biting tasks.MethodsSixteen healthy individuals (age: 24.5 ± 2.4 years) participated in experiment I during which the participants were asked to “hold and split” half a roasted peanut placed on a force transducer with their front teeth. The participant performed ten series with ten trials of the “hold and split” behavioral task while vibratory stimulus was applied on the masseter muscle every alternate series. Further, fourteen participants participated (age: 25.2 ± 4.8 years) in experiment II during which they performed a series each of the behavioral task at baseline, an adjusted baseline without and with vibration as well as with and without visual feedback. Hold and split forces along with the variability of hold force and duration and force rate during the split were measured.ResultsThe results of the study showed an increase in the magnitude of the hold force (P = 0.002), force rate during the split (P < 0.001) and a significant decrease in the duration of split (P < 0.001) due to the vibratory stimulus. However, there was no significant effect of the vibratory stimulus on the variability of hold forces (P = 0.879) or mean split force (P = 0.683) during the “hold and split” behavioral task. The results of experiment II also showed an increase in hold force due to the vibratory stimulus (P < 0.001).ConclusionsVibratory stimulus to the masseter muscles impairs the oral force control during a standardized biting task and provide further insight into the sensorimotor regulation of the masticatory system.  相似文献   
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Human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) is one of the leading causes of morbidity and mortality in West Africa. Prevalence among the most productive age group in West and Central Africa stood at 1.5%, 3.4.0%, 2.5%, and 2.1% in 1990, 2000, 2010, and 2015 respectively. This study examined the effect of HIV/AIDS on economic growth in West Africa with focus on 11 countries. The augmented Solow model, rooted in the neoclassical growth theory, was used, which was operationalized using dynamic panel data modeling approach. Incidence, prevalence, number of people living with HIV/AIDS (PLWHA), and AIDS‐related deaths were used to measure HIV/AIDS. Estimations using system GMM returned statistically significant results while those of first difference and difference GMM were not. From the outcome of system GMM analysis, a percentage increase in incidence, prevalence, PLWHA, and AIDS deaths correspondingly reduced growth significantly through their effects on life expectancy by 0.15%, 0.02%, 0.004%, and 0.03%. Acquired immune deficiency syndrome deaths and PLWHA lowered economic growth through enrolment but not significantly. The import of the findings is that HIV/AIDS threatens growth through life expectancy in West Africa. Therefore, its spread in the subregion should be effectively contained while proper treatment should be provided for all infected persons.  相似文献   
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We used the dual capability of hyperpolarized 129Xe for spectroscopy and imaging to develop new measures of xenon diffusing capacity in the rat lung that (analogously to the diffusing capacity of carbon monoxide or DLCO) are calculated as a product of total lung volume and gas transfer rate constants divided by the pressure gradient. Under conditions of known constant pressure breath-hold, the volume is measured by hyperpolarized 129Xe MRI, and the transfer rate is measured by dynamic spectroscopy. The new quantities (xenon diffusing capacity in lung parenchyma (DLXeLP)), xenon diffusing capacity in RBCs (DLXeRBC), and total lung xenon diffusing capacity (DLXe)) were measured in six normal rats and six rats with lung inflammation induced by instillation of fungal spores of Stachybotrys chartarum. DLXeLP, DLXeRBC, and DLXe were 56 +/- 10 ml/min/mmHg, 64 +/- 35 ml/min/mmHg, and 29 +/- 9 ml/min/mmHg, respectively, for normal rats, and 27 +/- 9 ml/min/mmHg, 42 +/- 27 ml/min/mmHg, and 16 +/- 7 ml/min/mmHg, respectively, for diseased rats. Lung volumes and gas transfer times for LP (TtrLP) were 16 +/- 2 ml and 22 +/- 3 ms, respectively, for normal rats and 12 +/- 2 ml and 35 +/- 8 ms, respectively, for diseased rats. Xenon diffusing capacities may be useful for measuring changes in gas exchange associated with inflammation and other lung diseases.  相似文献   
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