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51.
流化床包衣技术具有效率高、传热传质性能好等优点,在制药行业中具有广泛的利用价值。包衣过程本质为复杂的气固两相流动,准确地理解气固流动行为及其流动特性、掌握流化床包衣及其放大规律,一直是国内外学者的研究重点。本文首先简介了流化床包衣的基本过程,然后以颗粒特性为基础,从颗粒的旋转、碰撞和形状3个方面综述其对包衣过程中气固流动特性的影响,以及对流化床包衣性能产生的影响,并进行简要分析。基于此,本文指出了后续研究需要重点突破的方向:从介观颗粒群尺度研究流化床包衣相似放大可能是解决传统相似放大难题的一个有效途径。 相似文献
52.
目的研究45 d-6°头低位卧床对尿液中Ca和P元素昼夜节律的影响,探讨卧床实验中骨丢失的可能规律与机制。方法收集卧床实验8名受试者尿样,每个时间段连续收集3 d。采用电感耦合等离子体发射光谱仪(ICP-OES)对尿样中的Ca,P和K三种元素的含量进行检测,并对Ca和P等元素的昼夜节律特征进行分析。结果尿Ca总含量在卧床前、中、后3个时间段无显著差异,但Ca元素的日间含量在卧床中的早期和晚期阶段都显著降低,在卧床后又恢复至接近卧床前水平。尿中P元素总含量在卧床中的早期显著升高,随后不断下降,到卧床晚期则显著低于卧床前水平,P元素在日间和夜间的变化趋势差异不大。反映骨质变化的Ca/P参数在卧床中和卧床后也有显著变化。此外,卧床实验也对尿液中Ca和P含量变化的昼夜节律具有影响。结论卧床实验对于尿中Ca和P含量及Ca/P参数产生显著影响,同时也影响了Ca和P含量的节律性,这些变化可能与卧床过程中骨代谢失衡有关。 相似文献
53.
54.
Layla Banihashemi Lei K. Sheu Aimee J. Midei Peter J. Gianaros 《Social cognitive and affective neuroscience》2015,10(4):474-485
Early life experience differentially shapes later stress reactivity, as evidenced by both animal and human studies. However, early experience-related changes in the function of central visceral neural circuits that control stress responses have not been well characterized, particularly in humans. The paraventricular nucleus of the hypothalamus (PVN), bed nucleus of the stria terminalis (BNST), amygdala (Amyg) and subgenual anterior cingulate cortex (sgACC) form a core visceral stress-responsive circuit. The goal of this study is to examine how childhood emotional and physical abuse relates to adulthood stressor-evoked activity within these visceral brain regions. To evoke acute states of mental stress, participants (n = 155) performed functional magnetic resonance imaging (fMRI)-adapted versions of the multi-source interference task (MSIT) and the Stroop task with simultaneous monitoring of mean arterial pressure (MAP) and heart rate. Regression analyses revealed that childhood physical abuse correlated positively with stressor-evoked changes in MAP, and negatively with unbiased, a priori extractions of fMRI blood-oxygen level-dependent signal change values within the sgACC, BNST, PVN and Amyg (n = 138). Abuse-related changes in the function of visceral neural circuits may reflect neurobiological vulnerability to adverse health outcomes conferred by early adversity. 相似文献
55.
《Digestive and liver disease》2014,46(7):652-657
The scarcity of human and structural resources for specialized gastroenterology care is a problem in many Western countries. Data regarding the resources for Italian Gastroenterology, so far lacking, have been thus searched and evaluated. Based on an agreement protocol between the Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO) and the Ministry of Health, national data regarding all Institutions providing gastroenterological care were analysed. Hospital beds in Gastroenterology units are presented by region, regimen of stay and per million inhabitants as of January 2011.Association of Hospital Gastroenterologists and Endoscopists also performed a survey of gastroenterology units in all Italian regions regarding number of ordinary/day hospital beds and the number of staff gastroenterologists.The Ministry data showed a total of 174 Gastronterology Units in Italy, a total of 2062 hospital beds for the discipline, for a proportion of 34.2 beds per million inhabitants.The Association of Hospital Gastroenterologists and Endoscopists survey showed a total of 1425 gastroenterologists in Italy.These data should represent a key reference for appropriate planning of specialized care for digestive diseases. 相似文献
56.
老龄化社会到来,护理资源严重短缺,造成老人生活质量下降,以科技创新助力智慧养老,是解决老人护理难题的关键。针对半失能老年人渴望有一定的独立自主参与日常活动的诉求,设计了一款床椅一体化多功能移动智能护理床,除了使其具备日常起坐、翻身、如厕等日常需求之外,注重对半失能老人能力的辅助。该智能护理床通过移动机器人辅助自主移动能力,通过语音、动作的识别辅助交互能力,通过全方位智能检测与控制以辅助老人健康管理。在结构设计的基础上,对护理床进行了人因功效仿真,分析结果表明,该护理床对老人的安全性及舒适度符合标准要求。 相似文献
57.
Virtually every eukaryotic cell has an endogenous circadian clock and a biological sex. These cell-based clocks have been conceptualized as oscillators whose phase can be reset by internal signals such as hormones, and external cues such as light. The present review highlights the inter-relationship between circadian clocks and sex differences. In mammals, the suprachiasmatic nucleus (SCN) serves as a master clock synchronizing the phase of clocks throughout the body. Gonadal steroid receptors are expressed in almost every site that receives direct SCN input. Here we review sex differences in the circadian timing system in the hypothalamic–pituitary–gonadal axis (HPG), the hypothalamic–adrenal–pituitary (HPA) axis, and sleep–arousal systems. We also point to ways in which disruption of circadian rhythms within these systems differs in the sexes and is associated with dysfunction and disease. Understanding sex differentiated circadian timing systems can lead to improved treatment strategies for these conditions. 相似文献
58.
Khan BA Sodhi JS Zargar SA Javid G Yattoo GN Shah A Gulzar GM Khan MA 《Journal of gastroenterology and hepatology》2012,27(6):1078-1082
Background and Aim: Nocturnal gastro‐esophageal reflux causes heartburn and sleep disturbances impairing quality of life. Lifestyle modifications, like bed head elevation during sleep, are thought to alleviate the symptoms of gastroesophageal reflux. We tested the hypothesis that bed head elevation might decrease recumbent acid exposure compared to sleeping in a flat bed. Methods: Patients of symptomatic nocturnal reflux and documented recumbent (supine) reflux verified by esophageal pH test entered the trial. On day 1, baseline pH was measured while the patient slept on a flat bed. Then patients slept on a bed with the head end elevated by a 20‐cm block for the next 6 consecutive days from day 2 to day 7. The pH test was repeated on day 2 and day 7. Each patient acted as his own control. Results: Twenty of 24 (83.3%) patients with mean age of 36 ± 5.5 years completed the trial. The mean (± SD) supine reflux time %, acid clearance time, number of refluxes 5 min longer and symptom score on day 1 and day 7 were 15.0 ± 8.4 and 13.7 ± 7.2; P = 0.001, 3.8 ± 2.0 and 3.0 ± 1.6; P = 0.001, 3.3 ± 2.2 and 1.0 ± 1.2; P = 0.001, and 2.3 ± 0.6 and 1.5 ± 0.6; P = 0.04, respectively. The sleep disturbances improved in 13 (65%) patients. Conclusions: Bed head elevation reduced esophageal acid exposure and acid clearance time in nocturnal (supine) refluxers and led to some relief from heartburn and sleep disturbance. 相似文献
59.
Michael S. Bienkowski Elizabeth S. Wendel Linda Rinaman 《The Journal of comparative neurology》2013,521(15):3406-3431
The central and medial extended amygdala comprises the central (CEA) and medial nuclei of the amygdala (MEA), respectively, together with anatomically connected regions of the bed nucleus of the stria terminalis (BST). To reveal direct and multisynaptic connections within the central and medial extended amygdala, monosynaptic and transneuronal viral tracing experiments were performed in adult male rats. In the first set of experiments, a cocktail of anterograde and retrograde tracers was iontophoretically delivered into the medial CEA (CEAm), anterodorsal MEA (MEAad), or posterodorsal MEA (MEApd), revealing direct, topographically organized projections between distinct amygdalar and BST subnuclei. In the second set of experiments, the retrograde transneuronal tracer pseudorabies virus (PRV) was microinjected into the CEAm or MEAad. After 48 hours of survival, there were no significant differences between monosynaptic and PRV cases in the subnuclear distribution or proportions of retrogradely labeled BST neurons. However, after 60 hours of survival, CEAm‐injected cases displayed an increased proportion of labeled neurons within the anteromedial group of BST subnuclei (amgBST) and within the posterior BST, which do not directly innervate the CEA. MEApd‐injected 60‐hour cases displayed a significantly increased proportion of retrograde labeling in the amgBST compared with monosynaptic and 48‐hour cases, whereas MEAad‐injected cases displayed no proportional changes over time. Thus, multisynaptic circuits within the medial extended amygdala overlap the direct connections making up this anatomical unit, whereas the multisynaptic boundaries of the central extended amygdala extend into BST subnuclei previously identified as part of the medial extended amygdala. J. Comp. Neurol. 521:3406‐3431, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
60.
目的观察模拟失重效应对下肢肌萎缩的影响及中药红景天的干预作用。方法 16名成年男性健康志愿者随机分为对照组(8人)和用药组(8人),进行45 d-6°头低位卧床模拟长期失重效应实验。卧床期间,用药组和对照组每天分别服用红景天(红益胶囊)和安慰剂。卧床前、中、后动态测量小腿围径;并采用MRI技术,测试和分析卧床前、后大腿和小腿肌群最大横截面积和肌肉体积的变化。结果1)卧床期间用药组和对照组小腿围径进行性下降,在卧床30和45 d均显著下降(P0.01),但用药组下降幅度显著减少(P0.05);2)卧床45 d,用药组和对照组大腿和小腿肌肉最大横截面积均显著降低(P0.01),其中小腿比目鱼肌下降幅度最大。用药组肌肉最大横截面积的减少较对照组均有改善作用(P0.05);3)对照组大腿和小腿肌群肌肉体积在卧床45 d均显著下降(P0.01),以比目鱼肌体积下降最为明显,用药组下降幅度显著减少,且比目鱼肌对抗作用最为明显(P0.01)。结论 45 d-6°头低位卧床引起进行性加重的肌萎缩,中药红景天可部分对抗模拟长期失重效应诱导的下肢肌萎缩。 相似文献