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11.
主要阐述空调水系统利用平衡阀调节系统阻力,保持系统水力稳定;利用软启动器实施水泵的平滑软启动;压差旁通阀的作用及选型安装;系统管道热膨胀等问题。  相似文献   
12.
三维骨建模在全膝关节置换术中韧带平衡的作用   总被引:3,自引:3,他引:0  
目的探讨以三维骨建模为基础、无需影像的计算机辅助系统在人工全膝关节置换术(totalknee arthroplasty,TKA)中韧带平衡的作用。方法2002年11月~2003年6月,采用后稳定型人工全膝关节,在Ceravision无需影像资料的三维骨建模系统导航监控下,辅助完成TKA21例。男5例,女16例,年龄64~79岁,平均72.4岁。其中2例既往行胫骨近端截骨术,1例行股骨远端截骨术。14例膝内翻,7例膝外翻。术前下肢全长X线正位片测量,内翻13°~外翻13°,平均2.36°;膝关节X线正位片测量,应力下内翻平均8.47°(内翻2°~内翻20°),应力下外翻平均3.63°(内翻7°~外翻12°)。结果术中导航系统测量,额面内翻12°~外翻10°,平均3.33°,与术前比较差异有统计学意义(P<0.05);额面应力下内翻平均6.47°(内翻0°~内翻24°),应力下外翻平均4.32°(内翻8°~外翻15°),与术前比较差异有统计学意义(P<0.05)。术毕导航系统测得膝内外翻平均0.175°(内翻2°~外翻3°),而术后下肢全长X线正位片测量平均0.3°(内翻3.5°~外翻1.5°),二者差异无统计学意义(P>0.05)。术后3个月关节活动度为105~130°,平均115°,膝关节额面松弛度0.2~0.5cm,平均0.27cm。人工膝关节胫、股骨假体取得满意的对位置入和韧带平衡,无关节失稳和髌骨脱位等并发症发生。结论以三维骨建模为基础、无需影像的Ceravision系统,具有三维立体定位、优化截骨,并通过旋转对位和韧带松解获得伸屈膝关节等距间隙与韧带平衡稳定的作用,近期临床疗效满意,可在TKA中常规使用。  相似文献   
13.
Background and Purpose . Patients with multiple sclerosis (MS) tend to have movement difficulties, and the effect of physiotherapy for this group of patients has been subjected to limited systematic research. In the present study physiotherapy based on the Bobath concept, applied to MS patients with balance and gait problems, was evaluated. The ability of different functional tests to demonstrate change was evaluated. Method . A single‐subject experimental study design with ABAA phases was used, and two patients with relapsing–remitting MS in stable phase were treated. Tests were performed 12 times, three at each phase: A (at baseline); B (during treatment); A (immediately after treatment); and A (after two months). The key feature of treatment was facilitation of postural activity and selective control of movement. Several performance and self‐report measures and interviews were used. Results . After intervention, improved balance was shown by the Berg Balance Scale (BBS) in both patients, and improved quality of gait was indicated by the Rivermead Visual Gait Assessment (RVGA). The patients also reported improved balance and gait function in the interviews and scored their condition as ‘much improved’. Gait parameters, recorded by an electronic walkway, changed, but differently in the two patients. Among the physical performance tests the BBS and the RVGA demonstrated the highest change, while no or minimal change was demonstrated by the Rivermead Mobility Index (RMI) and Ratings of Perceived Exertion (RPE). Conclusion . The findings indicate that balance and gait can be improved after physiotherapy based on the Bobath concept, but this should be further evaluated in larger controlled trials of patients with MS. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
14.
The objective of this review is to identify and review publications describing the impact of reduced somatosensation on balance. Based on knowledge of the association between specific somatosensory loss and deterioration of balance, conclusions can be made about role of somatosensation in standing balance.A systematic literature review is presented in which publications from the years 1993 through 2007 were searched in Medline and Embase. Medical Subject Headings (MESH) terms and free text words (related to balance, somatosensory loss, and lower limb) were used to perform the searches. Fifteen articles were selected for detailed review based on predetermined inclusion criteria, and three of the included articles described the effect of experimentally reduced somatosensation on balance in healthy subjects. Ten of the articles described balance in diabetic neuropathy (DN). The last two included articles described balance in Charcot-Marie-Tooth (CMT) disease type 1A (CMT1A) or type 2 (CMT2).The literature indicates that the tactile sensation is reduced in DN, CMT1A, and CMT2 and when the plantar surface of the feet was hypothermically anesthetized. Joint motion sensation seems to be impaired in patients with DN, and passive joint position sensation appears to be reduced in healthy subjects with anesthesia of ankle and foot from prolonged ischemia. This reduced somatosensation seems to have a negative effect on balance in patients with DN and CMT2; however, this appeared not to be the case in patients with CMT1A and in healthy subjects.  相似文献   
15.
Neural plasticity of modality-nonspecific and modality-specific memory and learning abilities pertains to fluid intelligence and crystallized intelligence, respectively. The limbic system with the novelty neurons of the hippocampus interacts with the prefrontal cortex optimization of the orienting reflex and voluntary attention. Brain-derived neurotrophic factor produced by novelty neurons of the hippocampus contributes to long-term memory formation and improves learning abilities in a wide range of disciplines. Synergistic combination of stimulation with “analytical-specific visual perceptual patterns” and “optimally high” physiological activation of the bilateral electrodermal system optimizes the limbic system and prefrontal cortex activity as demonstrated by enhanced prefrontal N450 ERPs to a memory workload paradigm. This is accompanied by improvements in auditory retention tasks, word memorization, higher school achievement and marks, and an amelioration of “analytical-specific perceptual skills” as measured by the Mangina-Test. Intracerebral ERPs to a memory workload paradigm contributed to the elucidation of limbic structures and neocortical sites involved in memory workload processes. The progressive degeneration of these same structures causes the gradual decline of memory functions observed in early Alzheimer's disease. Research findings indicate that ERPs elicited by a memory workload paradigm are sensitive markers for diagnosis, treatment and clinical follow-up of early Alzheimer's patients. In addition, ERPs provide objective measurement of cholinergic medication effects on cerebral functions involved in memory processes through neuropsychophysiological parameters.  相似文献   
16.
目的 探讨门腔分流术后病人给予含丙氨酰 谷氨酰胺双肽 (Ala GLN)肠外营养 (PN)的安全性 ;观察其营养支持的效果 ,及对肠道通透性的影响。方法  16例病人随机分为两组。对照组(n =7)接受不含GLN的PN ;实验组 (n =9)接受含Ala GLN双肽的PN。两组自术后第 1天起给予等氮、等热量的PN共 7d ,于PN前后分别测定血清前白蛋白、氮平衡变化、血清GLN浓度、血氨、尿乳果糖 /甘露醇排泄率比值 (L/Mratio)、生化和临床指标的变化。结果 对照组术后血清GLN水平比术前显著降低 ,术后实验组GLN水平 (5 77± 4 2 ) μmol/L显著 (P =0 0 0 9)高于对照组术后水平 (499± 6 1)μmol/L ;两组术前的L/M比率均明显高于国人正常水平 ,术后对照组L/M水平 (0 0 95± 0 0 34)显著 (P=0 0 4 5 )高于实验组 (0 0 6 4± 0 0 2 3) ;两组累积氮平衡无显著性差异 ,但实验组第 5~ 7天期间氮平衡要明显优于对照组 ,实验组第 5天氮平衡 (- 15 3± 4 6 9)mg·kg-1·d-1显著 (P =0 0 4 3)好于对照组 (-92 7± 90 5 )mg·kg-1·d-1;对照组术后血清前白蛋白水平较术前显著下降 ,实验组术后血清前白蛋白水平 (0 2 6 9± 0 0 37)g/L显著 (P =0 0 0 1)高于对照组 (0 199± 0 0 2 7)g/L ;两组术后血氨水平相比无统计学意义 ;生  相似文献   
17.
Paul L. Booth  W. Eric Thomas   《Brain research》1991,548(1-2):163-171
Ramified microglial cells were investigated in primary cultures of dissociated cerebral cortical tissue from rats. The identification of these cells was confirmed through immunohistochemical staining with 7 monoclonal antibodies selective for microglia. While there was significant variation in staining intensity with different antibodies, all stained the identified ramified cells; the antibodies OX-42 and ED1 yielded the most intense immunoreactivity. Based on distinctive morphological features, the microglia could be identified in living cultures where they were monitored using time-lapse video recording. This technique revealed extremely dynamic features of cellular plasticity and motility. Ramified microglia exhibited constant and rapid alterations in the size and shape of their cell body with an associated extension and retraction of processes; concomitantly, the cells moved about in a circumscribed area. These features of plasticity and motility were unique to this cell type, and correlated with OX-42 immunostaining. The microglia also possessed a differentially high level of pinocytotic activity; this too was correlated with OX-42 staining. From the nature of their morphological plasticity and motility, high pinocytosis, and cellular distribution, it is hypothesized that the ramified microglia specifically function as a system of fluid cleansing in normal brain tissue.  相似文献   
18.
Accurate assessment and replacement of blood loss and fluid–electrolyte deficit during craniosynostosis repair is difficult owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was used in 4 ml kg–1 h–1 except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients (10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment of the primary craniosynostosis. Received: 16 February 1998  相似文献   
19.
PURPOSE: This study compared the near phoria measurement using the Bernell muscle balance card with and without prism neutralization, using both trial frame and phoropter correction, and compared with the conventional Maddox rod method. METHODS: Forty young normal Chinese adults had their near phoria measured with trial frame correction using the conventional muscle balance card method (method 1). Any deviation was compensated with a prism bar as an alternative approach (method 2). The conventional Maddox rod method (method 3) was also carried out for comparison. These three methods were repeated with phoropter correction and considered as methods 4, 5 and 6. RESULTS: The phorias obtained from these six methods were not significantly different from each other (repeated measures anova, p > 0.05). More than half of the subjects were exophoric. Although the difference in phoria was not significant, phoria measurement using phoropter correction yielded a greater coefficient of variation. CONCLUSIONS: Near phoria measurement using the muscle balance card conducted with trial frame correction was less variable, and was also more natural and similar to a real reading situation. The use of prism for compensation did not affect the phoria results. Exophoria seems to be more common than esophoria in young Chinese adults.  相似文献   
20.
全麻复合硬膜外麻醉患者林格氏溶液的容量动力学   总被引:1,自引:0,他引:1  
目的 通过确定全麻复合硬膜外时麻醉林格氏溶液的容量动力学模型参数,评价硬膜外复合全麻对晶体液扩容效应的影响。方法择期行肝癌切除术患者20例,随机分为2组:组Ⅰ麻醉诱导前行扩容治疗,组Ⅱ硬膜外复合全麻诱导后行扩容治疗。扩容采用30ml/kg乳酸钠林格氏溶液(LR)恒速输注,30min内输完,输注LR开始后90min内每5min测定血红蛋白(Hb)及红细胞压积(Hct),并记录总尿量及血液动力学数据。用容量动力学数学模型和物质守恒定律处理数据,获得结果。结果 组Ⅱ容量增加量、容量扩张效率、输注结束时液体保留率均高于组Ⅰ(P〈0.05)。一级容量动力学分析结果:组Ⅰ目标容积(V)和清除率(k1)均大于组Ⅱ(P〈0.05)。二级容量动力学分析结果:组Ⅱ的V1、k1、k1均高于组Ⅱ(P〈0.05)。扩容后组Ⅱ的平均动脉压、中心静脉压、心输出量均小于组Ⅰ(P〈0.05)。结论 全麻复合硬膜外麻醉可提高晶体液的容量扩张效率。  相似文献   
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