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1.
The present study investigated the characteristics of the middle-latency negative potential of event-related potentials (ERPs) using somatosensory go/nogo tasks. We manipulated interstimulus interval (ISI) in Experiment 1 and stimulus probability in Experiment 2 and analyzed the subtracted difference waveform resulting from subtraction of the ERP evoked by the go stimulation from that evoked by the nogo stimulation. In Experiment 1, the peak latency of negativity became significantly longer as the ISI increased, but the peak amplitude was unchanged. The reaction time (RT) was longer with increasing ISI. In Experiment 2, manipulation of the stimulus probability yielded an increase in peak amplitude with decreasing probability of the nogo stimulus, but did not affect the latency. The RT increased as the probability of a nogo stimulus rose. Because manipulation of the ISI and stimulus probability elicited different brain activities, we hypothesized that manipulation of the ISI elicited a delay of the stimulus evaluation process including response inhibition, and that stimulus probability significantly affected the strength of the response inhibition process.  相似文献   
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The P3(00) is an electrophysiological index of neural processing that varies with such stimulus parameters as interstimulus interval (ISI) and target probability, with a common view being that it reflects an endogenous form of memory update. Building on previous research, we argue that relations between P3 amplitude and both ISI and probability may be attributable to the target-to-target interval (TTI). Employing between-subject (Experiment 1; N = 24) and within-subject (Experiment 2; N = 10) designs, the present paper addresses this by testing subjects on a standard two-tone auditory oddball task as well as a one-tone task. In both studies, P3 amplitude increased and latency decreased linearly with TTI, and these relations were relatively unaffected by ISI or probability. This suggests that ISI and probability per se do not independently affect P3 amplitude, and that TTI offers a strong explanation of the reported relations between P3 amplitude and both ISI and probability.  相似文献   
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Because prepared learning has been defined in terms of response acquisition in spite of degraded input, it was expected that differences in resistance to extinction between skin conductance responses conditioned to potentially phobic and neutral stimuli would increase with increased interstimulus interval (ISI) and be larger with a trace than with a delay conditioning paradigm. Twelve groups with 10 subjects each were observed in a differential conditioning experiment manipulating ISI (2, 8, or 16 sec), paradigm (delay versus trace), and fear-relevance of the conditioned stimulus (potentially phobic versus neutral). The results showed highly reliable resistance to extinction of first-interval anticipatory responses to phobic stimuli, and no resistance to extinction of the corresponding responses to the neutral stimuli. This difference did not interact either with the ISI or the paradigm factor. Thus, although underscoring the reliability of the difference in conditioning to potentially phobic and neutral stimuli, the results did not support the specific hypothesis of conditioning to phobic stimuli as being less dependent on the ISI parameters than conditioning to neutral stimuli.  相似文献   
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国际敏感指数在血浆凝血酶原时间测定中的应用   总被引:1,自引:0,他引:1  
目的 :分析在测定 PT- INR实验过程中建立实验室敏感指数 (L ocal ISI)值的方法和必要性。方法 :在 CA- 15 0 0全自动凝血仪上使用 INR定标血浆建立 INR标准曲线 ,并做回归分析 ,计算出 L ocal ISI值 ,并利用 Dade- behring公司产品 Thromborel S凝血活酶试剂 ISI值和 L ocal ISI值分别测定 4 3例正常对照组和 2 0例长期口服抗凝药物治疗患者的凝血酶原时间 PT- INR,对两组结果进行统计处理。结果 :经校正本实验所用 Dade- behring公司产品 Throm borel S凝血活酶试剂 L ocal ISI值为 1.10 ,高于厂家提供的 ISI值。两组受试者利用 L ocal ISI值和 ISI值测定所得 PT- INR值差异有极显著性 (P<0 .0 1) L ocal ISI值组明显高于 ISI值组。结论 :直接利用试剂厂家标定的 ISI值进行 PT- INR值测定可能造成误差 ,仍应用 PT- INR定标血浆仪器上进行校正。利用实验室敏感指数 (L ocal ISI)值测定 PT- INR具有可信性 ,可应用于口服抗凝药物治疗监测  相似文献   
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Objective:To compare and evaluate the clinical effects on patients with poststroke insomnia of various acupuncture and acupuncture-related therapies.Methods:In order to analyze the direct and indirect evidence from related studies, we used network meta-analysis (NMA). In order to collect randomized controlled trials (RCTs) of acupuncture and related therapies in the treatment of poststroke insomnia, 3 English and 4 Chinese databases were searched. After 2 researchers independently screened the literature, extracted the information, and assessed the probability of bias in the included studies, the data was analyzed using Stata15.0 and WinBUGS1.4.3 software.Results:Based on the existing data, the pros and cons of different acupuncture-related therapies are compared extensively, the effectiveness of different acupuncture-related therapies is ranked compared to drugs with hypnotic effect in poststroke insomnia care, and the best methods or combinations of acupuncture intervention are summarized.Conclusion:This study will provide new evidence for the safety and effectiveness of acupuncture-related therapies in the treatment of poststroke insomnia, and may be helpful for clinicians, poststroke insomnia patients, and clinical guideline makers to choose the optimal combination of acupuncture for the treatment of poststroke insomnia.Registration Number:INPLASY202120028.  相似文献   
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It has been suggested that the P300 component of the ERP is an electrophysiological index of memory-updating processes associated with task-relevant stimuli. Component magnitude varies with the time separating target stimuli (target-to-target interval: TTI), with longer TTIs eliciting larger P300 amplitudes. According to the template-update perspective, TTI effects observable in the P300 reflect the updating of stimulus-templates in working memory (WM). The current study explored whether young adults' memory-task ability could predict TTI effects in P300. EEG activity was recorded from 50 university students (aged 18–25 years) while they completed an auditory equiprobable Go/NoGo task with manipulations of TTIs. Participants also completed a CogState® battery and were sorted according to their WM score. ERPs were analysed using a temporal PCA. Two P300 components, P3b and the Slow Wave, were found to linearly increase in amplitude to longer TTIs. This TTI effect differed between groups only for the P3b component: The high WM group showed a steeper increase in P3b amplitude with TTI than the low WM group. These results suggest that TTI effects in P300 are directly related to WM processes.  相似文献   
8.
The Q Hemostasis Analyzer (Grifols, Barcelona, Spain) is a fully-automated random-access multiparameter analyzer, designed to perform coagulation, chromogenic and immunologic assays. It is equipped with a cap-piercing system. The instrument was evaluated in a hemostasis laboratory of a University Hospital with respect to its technical features in the determination of coagulation i.e. prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin time, fibrinogen and single coagulation factors V (FV) and VIII (FVIII), chromogenic [antithrombin (AT) and protein C activity] and immunologic assays [von Willebrand factor antigen (vWF:Ag) concentration], using reagents from the analyzer manufacturer. Total precision (evaluated as the coefficient of variation) was below 6% for most parameters both in normal and in pathological ranges, except for FV, FVIII, AT and vWF:Ag both in the normal and pathological samples. No carryover was detected in alternating aPTT measurement in a pool of normal plasma samples and in the same pool spiked with unfractionated heparin (> 1.5 IU/mL). The effective throughput was 154 PT, 66 PT/aPTT, 42 PT/aPTT/fibrinogen, and 38 PT/aPTT/AT per hour, leading to 154 to 114 tests performed per hour, depending of the tested panel. Test results obtained on the Q Hemostasis Analyzer were well correlated with those obtained on the ACL TOP analyzer (Instrumentation Laboratory), with r between 0.862 and 0.989. In conclusion, routine coagulation testing can be performed on the Q Hemostasis Analyzer with satisfactory precision and the same apply to more specialized and specific tests.  相似文献   
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本研究主要观察格列吡嗪控释片对 2型糖尿病患者胰岛素敏感性的影响。1 对象和方法1.1 对象 选择 1999年 6月~ 2 0 0 2年 3月在我院住院治疗的按 ADA标准确诊的 2型糖尿病患者 77例 ,男 45例 ,女 3 2例 ,年龄 60~ 72岁 ,病程 4~ 15年。其中并发冠心病 15例 ,脑梗死 11例 ,周围神经病变 18例 ,视网膜病变 9例 ,白内障 4例。患者均无急性并发症 ,观察期间均未用其他磺脲类药物或胰岛素治疗 ,只给予饮食治疗及口服二甲双胍和 /或拜糖平治疗。观察期间用药量不变。本组按照体重指数 (BMI)分为两组 :BMI<2 5者为 A组 ,BMI≥ 2 5者为 …  相似文献   
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