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81.
Thermoregulatory heat-loss responses at high ambient temperatures were studied in intact cats and those with bilateral electrolytic lesions in the pontine tegmentum during wakefulness (W), slow-wave sleep (SWS), paradoxical sleep (PS) and PS without atonia induced by the lesions. Panting (respiratory rate 90/min) was present W, SWS, and in some cases, during PS. The percentage of the PS episodes with panting was directly related ambient temperature. In intact cats at 30 °C, panting occurred in 8% of the PS episodes; at 35 °C, in 52%, and at 40 °C, in 77%. The percentage of PS episodes with panting higher in the pontine-lesioned cats (90% at 35 °C), probably another indication of the altered thermoregulation of such animals. Thermoregulatory responses to heat load, and thermoregulation in general, have previously been shown to be suppressed in PS. Because hypothalamic thermosensitive neurons lack thermal responses during PS, the partial activation of heat-loss responses observed here may depend upon the function of extrahypothalamic brainstem areas.  相似文献   
82.
Alterations in presynaptic and postsynaptic dopaminergic system and cerebral glucose metabolism in corticobasal degeneration (CBD) were assessed to evaluate the potential usefulness of different imaging methods for CBD. (123)I-FP-CIT/(123)I-beta-CIT SPECT and (123)I-IBZM SPECT as well as (18)F-FDG PET were performed in eight CBD patients. Decreased presynaptic dopamine transporter binding was found in all CBD patients while D2 receptor binding was reduced in only one patient. (18)F-FDG PET displayed a contralateral hypometabolism in cortical and subcortical areas in seven out of eight patients. Our results demonstrate that glucose metabolism and DAT are reduced, while D2 receptors may be frequently preserved in CBD.  相似文献   
83.
5地市720名高中学生睡眠状况相关因素分析   总被引:4,自引:0,他引:4  
目的了解省级示范高中学生睡眠状况及相关因素对学生睡眠的影响,为相关部门制订针对性改进措施提供依据。方法采用睡眠状况自评量表(self-rating scale of sleep,SRSS)对省级示范高中学生进行睡眠状况问卷调查,用SPSS 10.0 FOR WINDOWS进行数据的统计与分析。结果发现720名省级示范高中学生睡眠状态异常者占65.42%,显著高于全国常模(45.6%)。其中轻度睡眠问题占57.36%,显著高于全国常模(35.6%)。学业负担过重、缺乏良好的学习习惯、住宿条件差、家庭状况不好、家校距离远和心理问题是导致省级示范高中在校学生睡眠状态异常的主要因素。结论应促进高中生身心健康,提高其学习能力,改善其睡眠状况。  相似文献   
84.
The objective of the study was to investigate the effects of oral appliance (OA) therapy on ambulatory blood pressure in patients with obstructive sleep apnea (OSA). Eleven OSA patients who received OA therapy were prospectively investigated. Ambulatory blood pressure was measured for 20 h from 4:00 p.m. to 12:00 noon the next day using an ambulatory blood pressure monitor. The Respiratory Disturbance Index (RDI) was measured in the pretreatment and posttitration periods. The OA was titrated to reach a therapeutic jaw position over 2 to 8 months, and posttitration measurements were repeated. At posttitration, the RDI was significantly decreased from a mean (SD) of 24.7 (20.1) to 6.1 (4.5). Significant reductions in diastolic blood pressure (DBP) and mean arterial pressure (MAP) were found for the 20-h periods, and systolic blood pressure (SBP), DBP, and MAP while asleep. The mean values were 79.5 (5.5) to 74.6 (6.0) for DBP and 95.9 (5.4) to 91.2 (5.9) for MAP, for over a 20-h period, and 118.4 (10.0) to 113.7 (9.1) for SBP, 71.6 (8.0) to 67.2 (7.9) for DBP, and 88.4 (8.0) to 83.9 (7.5) for MAP, while asleep. This study suggests that successful OSA treatment with an OA may also be beneficial to lower blood pressure in OSA patients, as previously suggested for nasal continuous positive airway pressure therapy. This study was conducted in the Division of Orthodontics, The University of British Columbia, Canada  相似文献   
85.
赵伟  任霖  张卫泽 《宁夏医学杂志》2004,26(11):701-702
目的 比较高血压合并阻塞性睡眠呼吸暂停患者的短期血压变异性。方法 将155例分为对照组、高血压组、高血压合并轻度或中重度阻塞性睡眠呼吸暂停组,EE较患者不同活动状态的短期血压变异性。结果 高血压合并中重度阻塞性睡眠呼吸暂停组患者睡眠期间和早晨血压变异系数分别为:收缩压18.69、21.32;舒张压19.41、23.61,明显高于其他各组。结论 夜间睡眠期间和早晨短期血压变异性增加,是高血压合并中重度阻塞性睡眠呼吸暂停患者夜间和早晨心血管事件发生率增加的重要危险因素。  相似文献   
86.
采用LabVIEW技术完成对心电、呼吸、无创血氧和无创血压信号的采集与处理,而后通过MATLAB模糊测量系统对采集的人体生理信号进行模糊预测分析。通过实验检验了人体生理信号检测、处理和模糊预测分析方法的可靠性。LabVIEW技术对人体生理信号的模糊预测分析是有效的,可用于检测阻塞性睡眠呼吸暂停患者的生理状态信号。  相似文献   
87.
支气管扩张症辨证模式初探   总被引:4,自引:0,他引:4  
目的:探讨支气管扩张症的中医辨证分型规律及证候特点.方法:通过对563例支气管扩张症的临床流行病学调查,采集以症状、体征、舌、脉及相关理化检测为变量的基本信息,以频数分析、聚类分析、方差分析等方法,提炼支气管扩张症的证候分布规律及证候特点.结果:临床上支气管扩张症多见4种证候类型,分别为痰热壅肺证(45.65%)、肝火犯肺证(24.51%)、肺脾气虚证(22.38%)、气阴两虚证(7.46%).结论:较大样本的临床流行病学调查为研究支气管扩张症辨证分型规律提供了科学依据,并可以通过主症判别分析法建立证候识别模式,为临床实践提供依据.  相似文献   
88.
目的:研究外伤性脾切除术后中医辨证与免疫功能变化的关系.方法:选择15例脾切除和15例非脾切除患者作为观察对象,以其症状、舌苔、脉象及免疫功能的测定作为观察指标,观察其中医辨证与免疫功能变化.结果:脾切除组在术后早期可出现脾胃虚弱的证候群,同时免疫功能测定补体C3、免疫球蛋白IgG、免疫球蛋白IgM的水平明显降低,与非脾切除组有显著性差异.结论:脾切除容易造成患者术后出现的脾胃虚弱症候群,并降低患者的免疫功能.  相似文献   
89.
90.
Patients with obstructive sleep apnea (OSA), in comparison to controls, have increased levels of circulating epinephrine and norepinephrine, both of which are risk factors for the development of central serous chorioretinopathy (CSCR). The aim of this pilot study was to investigate the frequency of symptoms that suggest OSA in CSCR patients and normal controls. The Berlin Questionnaire, a validated research tool to assess risk for OSA, was administered to 29 patients who met the criteria for active, acute, non-steroid-induced CSCR and 29 controls matched for age and sex. In this retrospective case-controlled study, the main outcome measure was increased risk for OSA. The mean age of the patients was 47.8 years (range 29–72) and the mean age of controls was 47.3 years (range 25–70). Seventy-six percent (22) of both groups were men. Survey scores showed 58.6% (17) of patients with CSCR to be at an increased risk for OSA compared to 31.0% (nine) of controls. A conditional logistic regression analysis showed that the CSCR group had a higher proportion with an increased risk for OSA compared to the control group (odds ratio=3.67; 95% CI: 1.02, 13.14; P = 0.046). Patients with CSCR may be more likely than other adults to have OSA, and screening for this sleep disorder should be considered in this population. Further research is warranted to determine whether sleep apnea may contribute to the development of CSCR, and to assess whether treatment of sleep apnea might offer a new therapeutic option for some patients with CSCR.  相似文献   
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