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991.
992.
《中国现代医生》2021,59(19):175-178
目的 探讨针对性护理模式在冠心病心绞痛患者临床治疗中的应用效果,结合患者的心率血压及心理状态变化情况进行评价。方法 选取解放军东部战区总医院心血管内科2019年2月至2020年2月期间收治的74例冠心病心绞痛患者作为研究对象,应用随机数字表法,分为观察组37例,进行针对性护理模式,对照组37例,进行常规护理,对比两组患者的护理效果。结果 与对照组相比,观察组患者在护理后的心率(HR)水平[(76.17±4.82)次/min vs.(80.62±3.94)次/min]、收缩压(SBP)水平[(134.42±10.25)mmHg vs.(143.57±11.94)mmHg]、舒张压(DBP)水平[(88.92±7.63)mmHg vs.(44.73±5.05)mmHg]、心绞痛发作频次[(0.52±0.13)次/周vs.(1.47±0.31)次/周]以及焦虑自评量表(SAS)评分[(38.14±4.37)分vs.(93.71±5.09)分]相对更低(P0.05),与对照比,观察组患者的护理满意度相对更高(P0.05)。结论 冠心病心绞痛患者的治疗恢复期间,针对性护理模式的应用,可以有效纠正患者的心率、血压异常,同时改善其心理状态,减少症状的发作,改善患者的预后。 相似文献
993.
《Neuro-Chirurgie》2014,60(5):216-221
Background and purposeThe pathophysiology of the clinical manifestations in normal pressure hydrocephalus (NPH) remains obscure. Ventricular dilatation could generate forces on the paracentral fibers of the corona radiata (CR), hence interfering with their function and producing the classical clinical triad. The analysis of the regional displacement and deformation of the white matter bundles, forming the corona radiata and internal capsule, may clarify the relationship between ventricular dilatation and clinical manifestations in NPH.MethodAn experimental finite element (FE) analysis was used to simulate ventricular dilatation in 3 dimensions (3D) and to calculate the strain and deformation on the surrounding parenchyma. Magnetic resonance diffusion tensor imaging-based white matter tractography was then applied to retrieve the displacement and deformation exerted along various fiber bundles of the corona radiata and internal capsule. Anterior and posterior limb displacements and elongations were compared using a paired samples t-test.ResultsThe internal capsule, hence the corona radiata, of each cerebral hemisphere was segmented into anterior and posterior limbs. Mean displacements and elongations were calculated for each limb. Mean displacement was significantly larger in the anterior limb whereas mean deformation was larger in the posterior limb (P < 0.01).ConclusionThe present simulation demonstrates that ventricular dilatation does not have a homogeneous effect on the periventricular fibre tracts, with a particular load on the corticospinal tract. The affection of this tract remains thereby a potential factor in the generation of the NPH gait disorders. 相似文献
994.
Lulu Wang Changyuan Dong Dong-E Chen Zhen Song 《International journal of clinical and experimental pathology》2014,7(3):858-869
Coxsackievirus B (CVB) is a significant pathogen that causes pediatric central nervous system disease with acute syndromes commonly. The onset of its infection was abrupt, and after recovery there usually will be severe mental sequelae. The disease model for research was not established by the way of natural infection, although there are various investigations about the CVB-induced central nervous system (CNS) diseases. Thus, we have established an acute neonatal CNS disease mice model by CVB orally infecting. This model imitated the natural infection route and focuses the onset of CNS disease, inducing severe infection and lesion in the hippocampus and cortex regions, and the stability of the model was demonstrated. A pathology score system was developed for quantitative pathology analysis, which standardizes the CNS pathology analysis by statistics analysis. By this model, the track of CVB penetrating the blood brain barrier in vivo has been captured. One of the experimental strains CVB3/Macocy, as a new variant, was isolated, and its genomic RNA was cloned. According to its nucleotide sequence, we have characterized its genomic structure and defined its genotype. Based on the sequence, some mutations which do not change the CVB-induced CNS damage have been found. The model is an effective tool for studies on CVB-induced CNS diseases. 相似文献
995.
《Journal of Surgical Education》2014,71(3):426-433
BackgroundVirtual reality (VR) and physical model (PM) simulators differ in terms of whether the trainee is manipulating actual 3-dimensional objects (PM) or computer-generated 3-dimensional objects (VR). Much like video games (VG), VR simulators utilize computer-generated graphics. These differences may have profound effects on the utility of VR and PM training platforms. In this study, we aimed to determine whether a relationship exists between VR, PM, and VG platforms.MethodsVR and PM simulators for laparoscopic camera navigation ([LCN], experiment 1) and flexible endoscopy ([FE] experiment 2) were used in this study. In experiment 1, 20 laparoscopic novices played VG and performed 0° and 30° LCN exercises on VR and PM simulators. In experiment 2, 20 FE novices played VG and performed colonoscopy exercises on VR and PM simulators.ResultsIn both experiments, VG performance was correlated with VR performance but not with PM performance. Performance on VR simulators did not correlate with performance on respective PM models.ConclusionsVR environments may be more like VG than previously thought. 相似文献
996.
细胞中的DNA是辐射敏感的靶,击中DNA双链是导致细胞死亡的主要原因。但不同组织的细胞对射线的敏感性存在差异。为了更好的解析这种差异,线性二次模型(LQ模型)被提了出来,它用α/β来反映正常组织修复损伤的能力,较好的解释了肿瘤组织与正常组织反应的差别,为我们预测放射治疗中生物效应和预后提供了依据。但一直以来由于LQ模型涉及的知识范围较广,彻底掌握并熟练应用的难度较大,为此本文从LQ模型的提出,引入时间因子、修复因子等方面简述LQ模型发展和演变的基本过程,探讨LQ模型的局限和应用条件,以期对大家掌握应用该模型能有所帮助。 相似文献
997.
《Journal of neurotherapy》2013,17(4):63-75
ABSTRACT This paper describes a mixed general linear analysis of the quantitative electroencephalogram (qEEG). The modeling is similar to regression, which builds a regression or ‘best-fit’ model for the data structure but, in addition, provides for correlations between observations. A mixed linear model states that data consists of two parts: fixed effects and random effects. Fixed effects determine the expected values of the observations, while random effects account for the stochastic deviations from these expected values both between and within individuals. Since errors are independent between subjects, the deviations from the expected values may also be modeled using a repeated measures approach. The term ‘repeated measures’ in this model refers to data with multiple observations from one specific source. It is reasonable to assume that these observations from the same source are correlated, even if only slightly, in some measurable way. Consequently, statistical analysis of repeated measures data gives a more accurate prediction capability when the issue of covariation between these measures is addressed. With mixed model methodology now available (e.g., the mixed procedure [Mixed PROC] of the SAS® system), the covariance structure can be incorporated into the statistical model. Disregarding potential random effects not specific to single individuals and absorbing potential within-subject random effects into the covariance matrix allows one to work with a simplified model. The use of a mixed procedure and its method of modeling the data structure appear to provide an accurate and objective method of analysis resulting in quantifiable equations for testing predictions. Essentially, this method allows the physiological pattern of each individual in the study, not related to any other variable, to be represented and accounted for in the model. Several comparative examples will be used to highlight the information that can be hidden in data structures depending on the type of statistical analysis used. 相似文献
998.
Nephrolithiasis causes severe pain and is a highly recurrent pathophysiological state. Calcium-containing stones, specifically calcium oxalate (CaOx), is the most common type accounting for approximately 75 % of stone composition. Genetic predisposition, gender, geographic region, diet, and low fluid intake all contribute to disease pathogenesis. However, exposure to environmental pollutants as a contribution to kidney stone formation remains insufficiently studied. Lead (Pb2+) is of particular interest as epidemiological data indicate that low-level exposure (BLL = 0.48–3.85 μM) confers a 35 % increased risk of developing CaOx nephrolithiasis. However, mechanisms underlying this association have yet to be elucidated. Drosophila melanogaster provide a useful genetic model where major molecular pathophysiological pathways can be efficiently studied. Malpighian tubules (MT) were isolated from either Wild-Type or InsP3R knockdown flies and treated with oxalate (5 mM) ± Pb2+ (2μM) for 1 h. Following exposure, MTs were imaged and crystals quantified. CaOx crystal number and total area were significantly increased (˜5-fold) in Pb2+(pre-treatment) + oxalate-exposed MTs when compared to oxalate alone controls. However, CaOx crystal number and total crystal area in Pb2+ + oxalate-exposed InsP3R knockdown MTs were significantly decreased (˜3-fold) indicating the role for principal cell-specific InsP3R-mediated Ca2+ mobilization as a mechanism for Pb2+-induced increases in CaOx crystallization inset model of nephrolithiasis. 相似文献
999.
《Journal of investigative surgery》2013,26(6):405-414
ABSTRACTMesenchymal stem cells (MSC) have the potential to aid tissue regeneration. Intravenous (IV) MSC administration is currently being assessed following tissue injury. However, few studies have been performed to establish a safe and effective method of IV MSC infusion for newborns. We have established a safe, nontraumatic and effective technique for systemic MSC transplantation in newborn rats. Yellow-fluorescent-protein (YFP)-labeled MSC were characterized using MSC markers and their differentiation potential was confirmed. Rat pups were delivered by C-section on gestational day 21. The umbilical vein (UV) was cannulated and used for IV injection of MSC or saline control, which was performed under ultrasonographic imaging. An additional control group consisted of UV MSC injection in adult mice. Mean operating time, success rate of cannulation and death rate were recorded. YFP-MSC quantification in multiple organs was performed. Mean operating time was 3.9 ± 1.1 min. The success of UV MSC injection was 92.8%. The immediate and 24 hr delayed death rate for rat pups was significantly lower than that of adult mice (p < .05). No pups receiving saline injection died. After locating the patent foramen ovale (PFO) of newborn pups by ultrasonographic imaging, extra pulse-waves and wave-shape changes were detected when MSC were injected. The number of YFP-MSC was 15.8 ± 4.1 cells per visual field (CPVF) in the lungs, 2.9 ± 1.2 CPVF in the heart, and 19.8 ± 5.0 CPVF in the intestines. We conclude that IV MSC infusion through the UV is a convenient, safe, and effective method for systemic MSC transplantation in prematurely delivered newborn rats. 相似文献
1000.
Jakub Żmigrodzki Szymon Cygan Beata Leśniak-Plewińska MirosŁaw Kowalski Krzysztof KaŁużyński 《Ultrasound in medicine & biology》2017,43(1):206-217
The identification of a sub-endocardial infarction is of major interest in cardiology. This study evaluates the sensitivity of selected measures to the thickness of such an infarction. Synthetic ultrasonic data (long-axis view) of left ventricular models with inclusions were generated using Field II and meshes obtained from finite-element simulations, which also provided the reference for the estimates obtained from ultrasonic data. The displacements, the first and second component of the principal strain (ε1 and ε2), and several measures derived from these quantities were estimated. All estimates, except for the poorly estimated ε2, exhibited sensitivity to the presence and transmurality of the inclusion. The most sensitive was the gradient of the averaged transmural profiles of ε1, and ε1 averaged over the area corresponding to the transmural inclusion. The inflection point of the ε1 profile shifted toward the outer wall with increasing thickness of the non-transmural inclusion. 相似文献