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91.
The present study investigated the temporal structure of sleep propensity during 48 hours using an ultrashort 7-min sleep/13-min wake cycle. Eight subjects were tested under two experimental conditions of either attempting sleep, or resisting sleep after a monitored night in the laboratory. Electrophysiological recordings were carried out during the 7-min trials. The temporal structure and the overall level of sleepiness of the 48-hour sleep propensity functions calculated from the amount of total sleep in each trial revealed a high within-subjects stability. This was found both across the two days of the study within conditions, and across conditions. Also, diurnal levels of sleepiness were systematically related to nocturnal sleep parameters. Subjects having short nocturnal sleep latencies and higher sleep efficiencies slept more during the day. It is proposed that the structure and level of the sleep propensity function can be used to characterize individuals along two dimensions of somnotypology: "morningness-eveningness" and "sleepy-alert."  相似文献   
92.
Summary The effects of acute introduction and withdrawal of 2 new -adrenergic blockers, acebutolol and metoprolol, on sleep in normal subjects were investigated. Both the subjective effects of the drug and EEG sleep variables were determined during a baseline period with placebo and in relation to the drug. The results showed that neither drug had a significant effect on sleep pattern in normal subjects. However, a transient effect on certain sleep parameters was seen on the first night of drug administration, with complete return to baseline, on the following night without any evidence of rebound. Possible mechanisms to explain the central actions of -adrenergic blockers are briefly discussed.  相似文献   
93.
Benzodiazepine hypnotics increase NREM sleep and alter its EEG by reducing delta (0.3–3 Hz) and increasing sigma (12–15 Hz) and beta (15–23 Hz) activity. We tested whether the nonbenzodiazepine hypnotic, zolpidem (10 mg), produced the same pattern of sleep and EEG changes as two “classical” benzodiazepines, triazolam (0.25 mg) and temazepam (30 mg). Sleep EEG of 16 subjects was analyzed with period amplitude analysis for 3 nights during drug administration or placebo. The effects of zolpidem were in the same direction but generally of smaller magnitude than those of the classical benzodiazepines. These differences are more likely the result of non-equivalent dosages than different pharmacologic actions. Period amplitude analysis showed that the decreased delta activity resulted mainly from a decrease in wave amplitude. In contrast, the increased sigma and beta activity were produced by increased wave incidence. Delta suppression increased with repeated drug administration but sigma and beta stimulation did not. While these findings have little relevance for the clinical choice of hypnotics they may hold important implications for the brain mechanisms involved in hypnotic tolerance and withdrawal delirium.  相似文献   
94.
Objective: Sleep-disordered breathing has been hypothesized to have a close relationship with hypertension but previous studies have reported mixed results. This is an important health issue that requires further clarification because of the potential impact on the prevention and control of hypertension.Methods: The relationship between hypertension and three forms of sleep-disordered breathing (chronic snoring, breathing pauses and obstructive sleep apnea syndrome (OSAS)) was assessed using representative samples of the non-institutionalized population of the UK, Germany and Italy (159 million inhabitants). The samples were comprised of 13,057 individuals aged 15–100 years who were interviewed about their sleeping habits and their sleep symptoms over the telephone using the Sleep-EVAL system.Results: OSAS was found in 1.9% (95% CI: 1.2% to 2.3%) of the UK sample, 1.8% (95% CI: 1.4% to 2.2%) of the German sample and 1.1% (95% CI: 0.8% to 1.4%) of the Italian sample. OSAS was an independent risk factor (odds ratio (OR): 9.7) for hypertension after controlling for possible confounding effects of age, gender, obesity, smoking, alcohol consumption, life stress, and, heart and renal disease.Conclusions: Results from three of the most populated countries in Western Europe indicate that OSAS is an independent risk factor for hypertension. Snoring and breathing pauses during sleep appeared to be non-significant predictive factors.  相似文献   
95.
Severity of negative esophageal pressure (Pes) and apnea hypopnea index (AHI) were investigated in six cases of upper airway resistance syndrome (UARS) and 11 cases of obstructive sleep apnea syndrome (OSAS). The severity of negative Pes was represented by the highest peak (Pes Max) and the number of increased episodes (more than 13.5 cmH2O) per h (NPesI13.5). There was no significant correlation between Pes indices and AHI. Pes Max and NPesI13.5 were not different among severe OSAS (AHI > 30), mild OSAS (AHI < 30) and UARS. Apnea hypopnea index failed to represent the severity of negative Pes, which is an important aspect of the pathophysiology of sleep-disordered breathing.  相似文献   
96.
目的 :探讨 Snoreguard矫治器对阻塞性呼吸暂停综合征 ( OSAS)患者气道、睡眠结构的影响。方法 :选择 2 6岁~ 5 9岁患有 OSAS的患者 8例 ,在睡眠时分别配戴 Snoreguard矫治器 ,同时结合应用头颅侧位片、夜间多导睡眠图监测来测定分析配戴 Snoreguard矫治器的测量指标 ,进行统计分析。结果 :配戴 Snoreguard矫治器后 ,8例患者的AI值、平均呼吸暂停时间、AHI值均有显著性的降低 ( P<0 .0 1) ,Sa O2 显著增加 ( P<0 .0 1) ,HI值降低显著 ( P<0 .0 5 )。鼾声指数大幅度减轻甚至消失 ( P<0 .0 1)。配戴矫治器后下颌在水平向和垂直向的位移平均为 2 .0 3 mm和 8.74m m,IAS无显著变化 ,MAS变化明显 ( P<0 .0 5 ) ,最显著性改变的是上气道后间隙 ( SPAS) ( P<0 .0 1) ,SPL 减少 3 .64m m。结论 :Snoreguard矫治器是通过将下颌限制在一个前伸位 ,从而改变口咽部的结构影响上气道大小来达到治疗效果  相似文献   
97.
路菊 《现代医药卫生》2003,19(6):668-669
目的:探讨经鼻持续气道正压通气(nCPAP)治疗,对阻塞性睡眠呼吸暂停综合征(OSAS)合并高血压患者动态血压的影响。方法:22例男性患者行多导睡眠图(PSG)监测及动态血压检查确诊为OSAS合并高血压的患者,观察nCPAP治疗前后患者动态血压、多导睡眠图等多项指标变化。结果:nCPAP治疗后患者PSG参数明显改善:睡眠时最低SaO_2从(71.0±12.3)%上升到(91.7±7.3)%(P<0.01);RDI显著降低;同时24小时血压明显下降,治疗前血压(16.5±1.6/11.6±2.3Kpa),治疗后血压(13.7±1.5/9.3±1.4Kpa)(P<0.01)。结论:经鼻持续气道正压通气治疗阻塞性睡眠呼吸暂停综合征,不但可以纠正患者的呼吸暂停,改善临床症状,而且可能降低患者的血压。  相似文献   
98.
鼻塞对阻塞性睡眠呼吸暂停综合征发病影响的研究   总被引:4,自引:1,他引:4  
目的:探讨鼻塞对阻塞性睡眠呼吸暂停综合征(OSAS)发病的影响。方法:对18例诊断为鼻塞和腭咽平面阻塞的OSAS患者,单纯行鼻腔手术改善通气,6个月后复诊。结果:12例睡眠阻塞症状缓解,其中4例效果明显;6例无效。睡眠呼吸紊乱指数(AHI)由术前的29.9±2.1降至22.8±2.7;夜间最低血氧饱和度由(75.0±2.9)%升至(83.4±2.3)%;而体重指数无明显差异。无效组与有效组的术前AHI值差异有显著性意义。结论:鼻塞是OSAS的重要致病因素,早期治疗解除鼻塞是预防OSAS发病的重要措施之一;长期鼻塞引发的OS-AS患者,早期通过鼻腔手术解除鼻塞是治疗OSAS的有效方法之一。  相似文献   
99.
目的 观察重度阻塞性睡眠呼吸暂停低通气综合征 (obstructivesleepapneahypopneasyndrome ,OSAHS)围手术期病情变化和持续正压通气治疗 (continuouspositiveairwaypressure,CPAP)的影响 ,探讨围手术期治疗的必要性。方法  45例重度OSAHS患者均接受了完整保留悬雍垂的改良悬雍垂腭咽成形术。其中 2 4例不做围手术期CPAP治疗的作对照组 ,2 1例行围手术期CPAP治疗 :术前CPAP治疗 7d以上 ,于术后 1~ 3d夜应用自动调节治疗压力的CPAP(autotitratedCPAP ,AutoSet)进行治疗。治疗组患者术后第二夜在AutoSet治疗下同时做多导睡眠监测 (polysomnography,PSG)。对呼吸暂停低通气指数 (apneahyponeaindex ,AHI)、最低血氧饱和度 (lowestSaO2 ,LSaO2 )、血压以及睡眠结构等指标进行观察。结果 对照组 2 4例患者中有 6例于术后第二夜LSaO2 比术前下降 ,AHI升高 ,另外 1 8例患者LSaO2 升高 ,AHI下降。治疗组 2 1例患者CPAP治疗前AHI为 (61 1± 9 9)次 /h( x±s,以下同 ) ,LSaO2 为 65 0 %± 9 6 % ,手术前CPAP治疗后AHI为 (2 2± 1 4)次 /h ,LSaO2 为 94 5 %± 2 9% ,t检验P <0 0 0 1 ;手术前经CPAP治疗临床症状消失。术后患者均能良好耐受AutoSet治疗 ,术后第二夜应用AutoSet治疗时AHI为 (3 6± 1 8)次 /h  相似文献   
100.
目的:探讨阻塞性睡眠呼吸暂停综合征(OSAS)患病情严重程度与夜间心律失常的关系,以及经鼻持续气道内正压(n-CPAP)通气治疗对心律失常的作用。方法:101例阻塞性睡眠呼吸暂停综合征患按呼吸紊乱指数分轻、中、重三组,观察夜间平均心率变化、最大心率变化、最慢心率、最快心率及心律失常累计时间,比较组间差异性,并对16例患进行了n-CPAP治疗前后各项参数的比较。结果:夜间心率变化和夜间心律失常  相似文献   
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