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101.

1. 1. Acute effects of alcohol and diazepam on reaction time (RT) and event-related potential (ERP) measures were examined in 108 healthy male volunteers.

2. 2. The subjects engaged in a simple RT task at two levels of stimulus intensity during baseline and treatment sessions.

3. 3. Lower stimulus intensity produced increased RTs, increased ERP peak latencies, and suppression of peak amplitudes.

4. 4. Moderate and high doses of alcohol, and high doses of diazepam produced increased RTs. Alcohol suppressed P100 and N100 amplitudes, while diazepam suppressed P100 amplitudes only. P100 amplitudes were correlated to RTs under baseline and treatment conditions.

5. 5. These results were taken as evidence for impaired stimulus detection during alcohol and diazepam intoxication, with both drugs influencing sensory-perceptual processes and alcohol alone influencing the degree of attentiveness.

Author Keywords: alcohol; diazepam; event-related potentials; simple reaction time  相似文献   

102.
Optic nerve injury demonstrated by MRI with STIR sequences   总被引:1,自引:0,他引:1  
We studied nine patients with optic nerve injury associated with closed head trauma by magnetic resonance imaging (MRI) with short inversion time inversion recovery (STIR) sequences on 11 occasions from 4 days to 14 years after the injury: three studies were within 17 days and eight over 4 months to 14 years. MRI revealed abnormal high signal in 10 of the 11 injured nerves. MRI 4 days after the injury showed no abnormality.  相似文献   
103.
79只眼底病患眼的光照黄斑部试验(MPT)结果显示:中心性浆液性脉络膜视网膜病变、老年性黄斑变性渗出型和Rieger型中心性渗出性脉络膜视网膜病变患眼的光照黄斑恢复时间显著延长,其它黄斑部病变患眼也有不同程度的延长。本文结合眼底荧光血管造影和黄斑视野域值试验对光照黄斑部试验的机理进行了探讨。  相似文献   
104.
Ventilation and perfusion SPECT images during tidal breathing were studied in 15 cases of lung cancer using 81mKr gas and 99mTc-microspheres. Furthermore, functional images of V/Q ratio and Q/V ratio were prepared, and their clinical significance is descussed with reference to general lung function. There was a decreas in %VC and %FEV 1.0in 7 of 15 cases, and an increase of AaDo2 in the blood gas analysis in 12 of 15 cases. Both planar and SPECT images showed ventilation and perfusion abnormalities in all 15 cases. Of these, 12 patients showed matched ventilation and perfusion defects, 2 patients a dead-space effect and 1 patient a shunt effect. In comparing planar and SPECT images, depiction of ventilation and perfusion impairments were equally clear in 11 cases, but in 3, showing a lobar or segmental defect with a shunt effect, the SPECT images were superior. In a patient with markedly impaired function of the affected lung, the remaining function could not be depicted by SPECT. From the above, it seems that better information can be obtained for understanding the ventilation and perfusion states of lung cancer by adding the SPECT images to the planar image.  相似文献   
105.
The treatment times for the fabrication of Extensive Amalgam Restorations (EAR) as recorded in a longitudinal clinical trial at the Dental School in Nijmegen were analyzed. 269 EAR's with different retention methods were made on molars by three operators. A mean total treatment time of 60 min was found. The factor operator had a significant influence on all treatment phases resulting in a 26% difference in total treatment time between operators. Also significant influences were found in some treatment phases for the factor retention, side location of the tooth and extension of the restoration. The results of this study with regard to treatment times must be considered from the perspective of the quality of the care provided.  相似文献   
106.
Ten-year stability of cardiovascular responses to laboratory stressors   总被引:1,自引:0,他引:1  
In this study we examined test-retest stability of cardiovascular stress responses over a decade of the life span. Participants were 55 male college undergraduates. 19 years of age at initial testing, and 29 years of age at follow-up testing Stressors were a foot cold pressor and an aversive reaction time task. Cardiovascular measures included systolic and diastolic blood pressure, heart rate, and preejection period. For cold pressor, the magnitude and pattern of cardiovascular responses remained unchanged at the 10-year follow-up. For the reaction time task, the characteristic cardiovascular response patterns was preserved but with significant attenuation of magnitude. The present findings are consistent with previous observations of temporal stability but over a substantially longer test-retest interval. The long-term stability of stress responses is discussed in the context of stress test methodology, behavioral response demands, and maturation of the physiological systems involved in cardiovascular response expression.  相似文献   
107.
两种术式治疗多囊卵巢综合征的远期疗效追踪比较   总被引:1,自引:0,他引:1  
[目的]评价开腹卵巢楔形切除(OWR)和腹腔镜下双侧卵巢电灼开窗术(LOD)两种术式对多囊卵巢综合征(PCOS)的远期疗效.[方法]1981至2001年在我院诊断为PCOS并接受手术治疗的妇女共151例,其中行OWR 61例、LOD 90例,追踪分析两组妇女术后妊娠率、术后妊娠时间的分布及术前后月经模式变化.[结果]两组的临床特征具有可比性,OWR组累积妊娠率84%,LOD组累积妊娠率72%,两组间没有明显差异,绝大部分妊娠发生在术后18个月内;OWR组术后3个月、半年、1年、3年、5年及10年月经规律的妇女所占的比例分别是81.3%、81.3%、77.3%、77.6%、78.9%、85.2%,明显高于术前的31.1%(P值<0.05);LOD组术后3个月、半年、1年、3年、5年及10年月经规律的妇女所占的比例分别是80.6%、63.5%、56.7%、58.0%、57.6%、42.9%,明显高于术前的35.6%(P值<0.05);术后OWR组月经规律妇女占的比例明显高于LOD组(P均<0.05).[结论]两种术式的术后妊娠率相似.OWR比LOD更好、更长远地改善PCOS妇女的月经异常.  相似文献   
108.
磁共振灌注成像在脑胶质瘤中的应用与评价   总被引:4,自引:3,他引:1  
目的 :评价磁共振 (MR)灌注成像在脑胶质瘤病理分级诊断中的价值。 方法 :对 2 8例脑胶质瘤患者术前行MR灌注成像 ,采用GRE EPI序列 ,重建相对脑血容量 (rCBV)彩图后 ,以肿瘤对侧对应部位和对侧正常脑白质为参照 ,分别计算出肿瘤最大rCBV1及rCBV2 ,并与病理学分级进行对照分析。 结果 :低、高度恶性胶质瘤的最大rCBV1值分别为 1.38± 0 .36和 4 .32± 3.4 1,最大rCBV2值分别为 2 .83± 0 .76和 9.71± 6 .2 3;低、高度恶性胶质瘤的rCBV1或rCBV2值与病理分级之间差异均有显著性意义。另外 ,rCBV1、rCBV2间有高度相关性 (r =0 .736 ,P <0 .0 0 1)。 结论 :MR灌注成像对脑胶质瘤的术前分级诊断有重要价值。  相似文献   
109.
A restricted field of view (rFOV) approach for imaging a dynamic time series of volumes of limited spatial extent within a larger subject is described. The shorter readout with rFOV-MRI can be exploited to either limit image artifacts or increase spatial resolution. To accomplish rFOV imaging of a multislice volume for a dynamic series, an outer volume suppression (OVS) preparation that saturates signal external to a cylinder through the subject is followed by slice-selective excitation and a spiral readout. The pass- and stopband efficiencies of the OVS in an agar gel phantom were 97% (+/-1.5%) and 3% (+/-1%), respectively. Profiles of the temporal signal-to-noise ratio (SNR) were measured in a phantom and an adult brain. The rFOV sequence reduced distortions from off-resonance signal and T2*-induced blurring compared to a conventional sequence. Sequence utility is demonstrated for high-resolution rFOV functional MRI (fMRI) in the visual cortex. The rFOV sequence may prove to be useful for other multislice dynamic and high-resolution imaging applications.  相似文献   
110.
青年男性MMPI-215F量表应答时间效应分析   总被引:1,自引:1,他引:0  
目的分析青年男性心理测评中F量表条目应答时间,研究其相关影响因素和变化规律,并对该测评计算机化过程中应答时间的设定提供一定的参考.方法使用MMPI-215对全国18个省市的青年男性进行测试,利用计算机对时间记录,汇总分析.结果青年男性在F量表各条目平均应答时间(以下简称F均时)为4.57s;低于总测试的各条目平均应答时间(6.34 s)(P<0.01);F均时与F分数、应答前后不一致的条目数以及漏答条目数有显著相关;F均时受文化程度、年龄、城乡结构多种因素影响;每个条目的应答时间主要取决于条目汉字的个数.结论 F均时在测评中表现出一定的变化规律,可以结合临床进一步深入研究,使其成为评价青年男性性格特征的客观性指标之一.  相似文献   
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