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81.
皮肤组织热水烫伤传热分析   总被引:5,自引:2,他引:3  
目的:研究生物组织热水烫伤过程的传热规律及影响因素并由此进行烫伤程度预测。方法:基于Pennes生物传热方程,建立热水洒落皮肤组织所致烫伤过程的一般模型,研究生物组织内部的温度变化规律,并对生物组织烫伤程度进行预测。结果:通过数值计算,得到生物组织内部的温度分布,以及生物组织烫伤发生的开始时间。研究表明,皮肤及内部组织初始温度分布、热水与皮肤表面的对流换热系数及热水的温度对于烫伤的发生有显著影响。结果:该模型可用于生物组织热水烫伤过程传热分析和烫伤预测,为烫伤的诊断和治疗提供依据。  相似文献   
82.
不同强度运动后大鼠心肌细胞热休克蛋白72mRNA的表达   总被引:5,自引:1,他引:4  
目的 :探讨不同运动强度和持续时间运动对大鼠心肌细胞热休克蛋白 72mRNA表达的影响。方法 :分别使SD大鼠进行低强度 (6 0 %VO2 max)、中等强度 (75 %VO2 max)和高强度 (85 %VO2 max)跑台运动 1天、2天和 3天 ,在末次运动结束后 2 4小时以RT -PCR法检测大鼠心肌细胞热休克蛋白 72mRNA的表达。结果 :在安静情况下大鼠心肌细胞存在HSP72mRNA的基础结构性表达 ;低强度运动 1天后心肌细胞HSP72mRNA表达与对照组相比无显著性差异 ,但随着运动时间的延长 ,HSP72mRNA表达逐渐增加 ;中等强度运动后心肌细胞HSP72mRNA表达随运动持续时间的延长显著增加 ,但运动 2天和 3天组表达量无显著性差异 ;大强度运动后心肌细胞HSP72mRNA表达随运动持续时间的延长显著增加。结论 :运动可以造成心肌细胞HSP72mRNA的表达增加 ,不同强度运动诱导心肌细胞HSP 72mRNA表达程度不同 ,且与运动持续时间存在内在关系。  相似文献   
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84.
The intensity dependence of the auditory-evoked potentials (IDAP) is inversely related to serotonergic tone. Depression is frequently observed after stroke, associated with cognitive impairment and increased mortality. Aim of this study was to investigate the serotonergic tone in acute stroke patients by IDAP. Consecutive patients with an acute stroke admitted in our stroke unit were evaluated using clinical and instrumental examinations and compared with healthy controls. The IDAP was calculated as the linear amplitude/stimulus intensity function (ASF) slope, by measuring the peak-to-peak amplitude of Nl-P2 on four blocks of different stimulus intensities. Twenty patients were enrolled; 11 had a right brain infarction; nine had depressive symptoms (DS). The ASF slope of the auditory-evoked potentials was markedly increased in stroke patients compared with controls ( P  = 0.021). Stroke patients with DS had a significant steeper ASF slope than controls ( P  = 0.017). There was no statistical difference in ASF slope between stroke patients without DS and controls. Post-stroke depression pathophysiology is still debated. Our study suggests that in acute stroke patients with DS, there is a direct involvement of the serotonergic system, regardless the degree of disability and the site of the lesion.  相似文献   
85.
Early Stroke Recognition: Developing an Out-of-hospital NIH Stroke Scale   总被引:1,自引:0,他引:1  
Objective : To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke.
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke.
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed.  相似文献   
86.
Improvementofheat-tolerancebytrainingⅡ.Evaluationofeffectsofcross-countryraceandheat-bathtrainingonheat-toleranceQiuRenzhi;Zh...  相似文献   
87.
Stroke rehabilitation is an area of practice that many occupational therapists encounter during their career. The literature promotes a wide range of management techniques and support devices for people who have a stroke-affected upper limb, but little is known about the validity of those that occupational therapists actually use in practice. A questionnaire was sent to occupational therapists working in Queensland and northern New South Wales facilities (n = 35), in which adults with a stroke were likely to be treated. Eighteen respondents answered questions about the management techniques and support devices used in their facility, and their perception of the benefit of these devices in the reduction of hemiplegic shoulder pain. Results are discussed with reference to evidence-based practice and indicate an urgent need for the collation and dissemination of the best current evidence available for the management techniques and support devices used in this area, as well as further research to extend this evidence.  相似文献   
88.
89.
We assessed predictors of spontaneous early neurological recovery after acute ischemic stroke by means of multivariate analysis in a cohort of 1,473 consecutive patients treated at one academic center. At hospital discharge, spontaneous neurological improvement or good outcome was defined as grades 0-2 of the Rankin scale, and poor outcome (no improvement or in-hospital death) as grades 3-5. Spontaneous recovery of neurological deficit at the time of discharge from the hospital was observed in 16% of patients with cerebral infarction (n = 238). Dysarthria-clumsy hand syndrome improved in 44% of patients and was the only variable significantly associated with in-hospital functional recovery in three logistic regression models that in addition to lacunar syndromes, included demographic variables, cardiovascular risk factors, and clinical variables [odds ratio (OR) 2.56], neuroimaging findings (OR 2.48), and outcome data (OR 2.39), respectively. Clinical factors related to severity of infarction available at stroke onset have a predominant influence upon in-hospital outcome and may help clinicians to assess prognosis more accurately. Our work gives a contribution into prognostic factors after acute ischemic stroke. With regard to patterns of stroke, dysarthria-clumsy hand syndrome was a significant predictor of spontaneous in-hospital recovery in ischemic stroke patients.  相似文献   
90.
热休克蛋白70-2基因在大鼠隐睾中的表达及意义   总被引:4,自引:0,他引:4  
目的 :探讨Hsp70 2基因表达在大鼠隐睾生精细胞中的作用。方法 :采用 2 2日龄Sprague Dawley雄性大鼠复制单侧隐睾模型 ,运用免疫组织化学SP法检测Hsp70 2和cdc2 基因在大鼠隐睾侧和对侧睾丸组织中的表达 ;运用生物素 dUTP 酶标亲和素测定法检测睾丸生精细胞凋亡。结果 :术后第 7d ,与对侧睾丸相比 ,隐睾侧Hsp70 2表达下降显著 (P <0 .0 1) ,cdc2 表达无显著性变化 (P >0 .0 5 ) ,生精细胞凋亡显著性增加 (P <0 .0 1)。术后第 14d ,隐睾侧生精细胞少见 ,Hsp70 2和cdc2 表达呈阴性。结论 :隐睾可以引起生精细胞发育停止和凋亡增加 ,这可能与Hsp70 2表达下降或不表达有关  相似文献   
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