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21.
王涛  李秋军 《护理研究》2006,20(28):2567-2568
早期下床活动的必要性已得到大家认可,但术后早期病人常常较虚弱,且下床活动时会引发一些不适,病人也会有一些担心和顾虑,这在一定程度上会影响病人下床活动的积极性。颈椎手术本身有其特殊性,术后对颈部的稳定要求较高,因此此类病人活动有其特点。本研究以颈椎术后已下床活动的病人为研究对象,通过问卷调查,了解颈椎手术后病人首次下床的感受和相关需求,为进一步提高颈椎术后护理质量提供依据。1资料和方法1.1对象采用方便取样,选取2005年4月—2005年6月在某三甲医院因颈椎病入院、术后已下床活动的病人75例。其中男54例,女21例;年龄28岁~7…  相似文献   
22.
The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anterior tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force-moment sensor testing system, valgus torques ranging from 0.0 to 10.0 Nm were applied in nine increments on the intact and ACL-deficient knee in flexion ranging from 0 degrees to 90 degrees. At 15 degrees of knee flexion, the coupled ATT and ITR were significantly increased in the ACL-deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p<0.05), while coupled ITR increased a maximum of 85% (5.1 degrees, p<0.05). At 30 degrees, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 Nm and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p<0.05) and a maximum increase in coupled ITR of 38% (3.6 degrees, p<0.05). At 45 degrees, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p<0.05), but only at torques > or =6.7 Nm. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 Nm was applied. Low valgus torque elicited tibial subluxation in the ACL-deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL-deficient and ACL-reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination.  相似文献   
23.
Previous work has shown that alterations in proteoglycan aggregates are among the first changes detected with aging, disuse, and degeneration of articular cartilage, yet the cause or causes of these alterations remain unknown. To determine if differences in link protein concentration can explain alterations in the assembly, size, and stability of articular cartilage proteoglycan aggregates, we isolated proteoglycan monomer (aggrecan) and link protein from adult bovine articular cartilage and then assembled proteoglycan aggregates from aggrecan and 0.8% hyaluronan relative to aggrecan weight, in the presence of 0, 2, 4, 6, 8, 10, 15, and 20% concentrations of link protein relative to aggrecan weight. We determined the amount, sedimentation coefficient, and stability of the aggregates by analytical ultracentrifugation and measured their dimensions by electron microscopy with use of the monolayer technique. Increased aggregate size, as determined by ultracentrifugation, was directly correlated with an increased number of aggrecans per aggregate and with increased hyaluronan length, as determined by electron microscopy. The concentration of link protein significantly influenced aggregation: concentrations of 6–8% produced maximum aggregation, aggregate stability, and uniformity of aggrecan spacing; concentrations greater than 10% led to the formation of superaggregates (aggregates with sedimentation velocities greater than 100 S that may result from linking two or more hyaluronan filaments) but decreased aggregate stability; and concentrations of less than 4% link protein significantly decreased aggregation, the size and stability of aggregates, and the regularity of aggrecan spacing. The latter observations suggest that a decline in the concentration of link protein could decrease the organization and stability of the articular cartilage matrix.  相似文献   
24.
25.
临床输液监控系统的设计   总被引:5,自引:0,他引:5  
本文针对临床输液过程中出现的漏、停、输液速度改变等各种问题,讨论了一由单台微机和多个单片机通讯实现的多床输液自动监控、自动反应、自动报答系统的可行性,并给出了主要部分的硬件、软件设计方法。  相似文献   
26.
Six human cytochrome P450s expressed in HepG2 cells using vaccinia virus cDNA-directed expression, were used to study the biotransformation of caffeine and its metabolites. CYP1A2 alone was responsible for caffeine 3-demethylation and paraxanthine 7-demethylation; in addition, 1A2 catalysed virtually all reactions related to caffeine and its metabolites. The metabolic profile of caffeine biotransformation by CYP1A2 averaged 81.5% for paraxanthine, 10.8% for theobromine and 5.4% for theophylline formation. It remained quite uniform when caffeine concentrations were varied. The most striking finding was that CYP2E1 (the ethanol-inducible form) had major influences upon caffeine metabolism: in particular, it catalysed the formation of theophylline and theobromine from caffeine. Thus, the in vivo metabolite profiling of caffeine may reveal CYP2E1 activities in addition to the previously documented activities of CYP1A2, polymorphic N-acetyltransferase and xanthine oxidase.  相似文献   
27.
观察了食饵性高血脂对新西兰兔血小板功能、纤溶系统和血液流变学的影响以及去纤酶的调节作用,并动态观察了指标的变化.结果发现,高血脂能引起兔的血小板数增加,粘附力增强,血液粘滞性增加,红细胞流动变慢,呈现高凝和低纤溶状态,且主动脉形成明显粥样斑块.去纤酶在降低血脂的同时,可明显降低血小板的粘附力,降低血液粘滞性,呈现低凝和高纤溶状态,其主动脉粥样斑块亦明显减轻和缩小.提示去纤酶既能降低血脂又能降低血粘稠度,促进纤溶,起到抗凝及防止血栓形成,抑制动脉硬化的形成和发展.  相似文献   
28.
The skeletal extracellular matrix produced by osteoblasts contains the glycoprotein fibronectin (Fn), which regulates the adhesion, differentiation, and function of osteoblasts. Fn fibrillogenesis is involved in the process of bone mineralization. Bone morphogenetic proteins (BMPs) can be isolated from organic bone matrix and are able to initiate de novo cartilage and bone formation. In this study, the effect of BMP-4 on Fn fibrillogenesis in cultured rat osteoblasts was examined. BMP-4 enhanced Fn synthesis and extracellular Fn assembly in primary cultured osteoblasts. In addition, the extracellular assembly of Fn from exogenously applied soluble human Fn was also increased by BMP-4. It has been reported that alpha5beta1 integrin is related to Fn fibrillogenesis. The synthesis of both alpha5 and beta1 integrins was upregulated by BMP-4. Immunocytochemistry showed that the clustering of alpha5 and beta1 integrins was also increased by BMP-4. BMP-4 increased fibril formation of Fn and the adhesion of osteoblasts onto Fn matrix, which was inhibited by disintegrin triflavin and Gly-Arg-Gly-Asp-Ser (GRGDS) peptide. Phosphorylation of extracellular signal-regulated kinase (ERK) and focal adhesion kinase (FAK) was increased by BMP-4. Enhancement of extracellular Fn fibrillogenesis and the mRNA expression of beta1 integrin by BMP-4 were inhibited by ERK kinase (MEK) inhibitor PD98059. These results suggest that the enhancement of extracellular Fn fibrillogenesis by BMP-4 in cultured osteoblasts is related to the increase of the synthesis of Fn and clustering of alpha5 and beta1 integrins. ERK is involved in the signaling pathway of BMP-4 in regulating Fn fibrillogenesis in osteoblasts.  相似文献   
29.
30.
鼻咽癌增强CT扫描的影像表现及价值(附102例报告)   总被引:7,自引:0,他引:7  
目的 探讨鼻咽癌 (NPC)增强CT表现和价值。方法 对 10 2例NPC放化疗前病人行平扫加增强扫描 ,观察癌灶密度变化、鼻咽表面线样强化层和癌灶周界情况。结果 平扫癌灶密度与同层面鼻咽肌相近的有 89例 (87% ) ,其余与翼外肌相近(13 % )。平扫难以明确癌灶的大小和范围 ,所能显示的仅是有无占位。增强扫描癌灶密度差异明显的占 44% ,单靠密度差异能使其周界全部或大部清楚的仅占 40 %。根据癌灶强化和线样强化层的表现 ,综合判断癌灶周界全部或大部清楚的达到 76%。结论 增强扫描对准确判断NPC癌灶的大小、范围以及对发现小的癌灶和鉴别诊断有重要作用。在主要针对鼻咽部本身的检查 ,增强也应列为常规扫描  相似文献   
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