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51.
本文全面系统地介绍了现代城市建筑中的屋面绿化技术,主要包括屋面构造、植物选型、栽培质选型、蓄排水选型、抗根防水层选型、保温层选型等内容,并介绍了几种不同的经济合理的绿化屋面构造方案,适用于新建及旧建筑中应用。通过系统地研究对屋面绿化技术,能有助于各地推广及应用屋面绿化技术。  相似文献   
52.
目的 探讨髋、膝关节手术病人血栓前状态和血液中凝血-纤溶系统的变化.方法 每组病人术前及术后1、4、7、10天检测TAT、PAP、血凝常规等指标;术前及术后第7天~10天应用彩色多普勒超声仪监测DVT.结果 ①手术组共有18例(40.9%)术后并发DVT,保守组共有9例(22.0%)并发DVT,对照组无DVT发生;②手术组术后并发DVT者术前及术后TAT均显著升高,而PAP水平较低;③术后并发DVT者与术前PAP/FB比值相关.结论 ①术前TAT检测可作为术后是否并发DVT的一项较有意义的预测指标.②术前较低的纤溶水平可能成为髋、膝关节置换术后DVT发病率高的原因之一.③术前血浆PAP/FB比值有望成为预测术后DVT的有用指标.  相似文献   
53.
We treated an infant with congenital central hypoventilation syndrome ("Ondine's curse"). She was cyanotic and given ventilatory support at the first hour after birth. An investigation of sleep state and respiration performed at the age of 3 months led to this diagnosis. Hypoventilation persisted in all sleep stages, with the most severely reduced tidal volumes occurring during delta-wave sleep (stages 3 and 4). In addition, severe secondary reduction in tidal volumes occurred in sleep-onset REM sleep. This phenomenon was absent in non sleep-onset REM sleep. At 4 months of age, her respiratory treatment was successfully converted to positive-pressure ventilation via a nasal mask, thus avoiding tracheotomy. This transition to noninvasive ventilatory support dramatically improved her quality of life during wakefulness. This report may be a clue to discuss the function of sleep-onset REM sleep seen in the early stage of life and suggests that nasal mask ventilation is a viable option in selected cases with congenital central hypoventilation syndrome (CCHS).  相似文献   
54.
Functional magnetic resonance imaging (fMRI) has been increasingly used in studying human brain function given its non-invasive feature and good spatial resolution. However, difficulties in acquiring data from peripheral (e.g. information from muscle) during fMRI studies of motor function hinder interpretation of fMRI data and designing more sophisticated investigations. Here we describe a system that was designed to concurrently measure handgrip force, surface electromyograms (EMG) of finger flexor and extensor muscles, and fMRI of human brain. The system included a pressure transducer built in a hydraulic environment, a heavily shielded EMG recording element, and a visual feedback structure for online monitoring of force and/or EMG signal, by the subject positioned in the scanner during an fMRI experiment. System evaluation and subsequent fMRI motor function studies have indicated that by using this system, high quality force and EMG signals can be recorded without sacrificing the quality of the fMRI data.  相似文献   
55.
醒脑静注射液对脑缺血再灌注氧化损伤的实验研究   总被引:11,自引:0,他引:11  
[目的]研究中药醒脑静注射液对沙土鼠急性脑缺血再灌注损伤的作用。[方法]采用沙土鼠双侧颈总动脉夹闭制作沙土鼠急性全脑缺血模型,观察干预性腹腔注射西药尼莫地平和中药醒脑静注射液对缺血再灌注急性期沙土鼠脑组织中MDA含量和SOD活力的影响。[结果]西药尼莫地平和醒脑静注射液均能显著提高脑缺血再灌注后SOD活力和降低MDA含量,醒脑静注射液疗效和西药尼莫地平无显著差异,而醒脑静大中小剂量组之间有较显著的差异,疗效随剂量的增加而增大。[结论]醒脑静注射液作为抗自由基损伤的中药和西药尼莫地平有相当的疗效。  相似文献   
56.
Theoretically, a haplotype has a higher level of heterozygosity than individual single nucleotide polymorphism (SNP) and the association study based on the haplotype may have an increased power for detecting disease associations compared with SNP-based analysis. In this study, we investigated the effects of four haplotype-tagging SNPs (htSNP) and the inferred haplotype pairs of the X-ray cross-complementing group 1 (XRCC1) gene on chromosome damage detected by the cytokinesis-block micronucleus assay. The study included 141 coke-oven workers with exposure to a high level of polycyclic aromatic hydrocarbons and 66 nonexposed controls. The frequencies of total MN and MNed cells were borderline associated with the Arg(194)Trp polymorphism (P = 0.053 and P = 0.050, respectively) but not associated with the Arg(280)His, Arg(399)Gln and Gln(632)Gln polymorphisms among coke-oven workers. Five haplotypes, including CGGG, TGGG, CAGG, CGAG, and CGGA, were inferred based on the four htSNPs of XRCC1 gene. The haplotype CGGG was associated with the decreased frequencies of total MN and MNed cells, and the haplotypes TGGG and CGAG were associated with the increased frequencies of total MN and MNed cells with adjustment for covariates among coke-oven workers. This study showed that the haplotypes derived from htSNPs in the XRCC1 gene were more likely than single SNPs to correlate with the polycyclic aromatic hydrocarbon-induced chromosome damage among coke-oven workers.  相似文献   
57.
穿心莲内酯微囊的制备及溶出度考察   总被引:6,自引:0,他引:6  
目的:研究以丙烯酸树脂Ⅳ号为囊材的穿心莲内酯微囊的制备方法及其体外溶出特点.方法:采用液中干燥法制备穿心莲内酯微囊,并按<中国药典>方法测定体外溶出度.结果:该法制备的穿心莲内酯微囊,在水中药物几乎没有溶出,而在酸性溶出介质中则可快速释放.结论:该方法所制备微囊不仅可以有效掩盖穿心莲内酯的苦味,而且在胃液中能够快速释放.  相似文献   
58.
Diabetic retinopathy (DR) is one of the leading causes of vision loss and can be effectively avoided by screening, early diagnosis and treatment. In order to increase the universality and efficiency of DR screening, many efforts have been invested in developing intelligent screening, and there have been great advances. In this paper, we survey DR screening from four perspectives: 1) public color fundus image datasets of DR; 2) DR classification and related lesion-extraction approaches; 3) existing computer-aided systems for DR screening; and 4) existing issues, challenges, and research trends. Our goal is to provide insights for future research directions on DR intelligent screening.  相似文献   
59.
It has previously been reported that propofol regulates the development of human osteosarcoma (OS). However, the specific molecular mechanisms underlying the effect of propofol on OS remain poorly understood. Therefore, the aim of the present study was to explore the effects of propofol on OS U2OS cells and the potential underlying mechanism. The Cell Counting Kit-8 and colony formation assays were performed to assess cell viability and proliferation. Furthermore, cell apoptosis was assessed using the TUNEL assay and western blotting. Wound healing and Transwell assays were performed to evaluate OS cell migration and invasion abilities, respectively. The protein expression levels of epithelial-mesenchymal transition (EMT)-, autophagy- and adenosine monophosphate-activated protein kinase (AMPK)/FOXO1 signaling pathway-related proteins were also determined using western blotting. The results demonstrated that propofol significantly reduced the viability of OS cells and promoted autophagy in a dose-dependent manner. Moreover, cell treatment with propofol significantly enhanced the protein expression levels of phosphorylated (p)-AMPK and FOXO1, while decreasing the protein levels of p-FOXO1. Furthermore, treatment with propofol significantly suppressed cell viability, migration and invasion abilities and the EMT of OS cells, and potentially promoted cell apoptosis via inducing autophagy via the AMPK/FOXO1 signaling pathway. In summary, the present study indicated that propofol potentially had an inhibitory effect on the development of OS cells via AMPK/FOXO1-mediated autophagy. These results have therefore provided an experimental basis for further studies into the therapeutic effect of propofol on OS.  相似文献   
60.
Robotic milling has broad application prospects in many processing fields. However, the milling performance of a robot in a certain posture, such as in face milling or grooving tasks, is extremely sensitive to process parameters due to the influence of the serial structure of the robot system. Improper process parameters are prone to produce machining defects such as low surface quality. These deficiencies substantially decrease the further application development of robotic milling. Therefore, this paper selected a certain posture and carried out the robotic flat-end milling experiments on a 7075-T651 high-strength aeronautical aluminum alloy under dry conditions. Milling load, surface quality and vibration were selected to assess the influence of process parameters like milling depth, spindle speed and feed rate on the milling performance. Most notably, the contribution ratio based on the analysis of variance (ANOVA) was introduced to statistically investigate the relation between parameters and milling performance. The obtained results show that milling depth is highly significant in milling load, which had a contribution ratio of 69.25%. Milling depth is also highly significant in vibration, which had a contribution ratio of 51.41% in the X direction, 41.42% in the Y direction and 75.97% in the Z direction. Moreover, the spindle speed is highly significant in surface roughness, which had a contribution ratio of 48.02%. This present study aims to quantitatively evaluate the influence of key process parameters on robotic milling performance, which helps to select reasonable milling parameters and improve the milling performance of the robot system. It is beneficial to give full play to the advantages of robots and present more possibilities of robot applications in machining and manufacturing.  相似文献   
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