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101.
Mounting evidence suggests that ethanol exerts effects on learning and memory by altering cellular activity in the hippocampus and related structures. However, little is actually known regarding ethanol's effects on hippocampal function in awake, freely-behaving animals. The present study examines the effects of ethanol on hippocampal place-cell and interneuron activity in freely-behaving rats. Signals from individual hippocampal neurons were isolated while subjects traversed a symmetric Y-maze for food reward. Following 15 min of baseline recording, subjects were injected with one of four doses of ethanol (0.0, 0.5, 1.0 and 1.5 g/kg), and cellular activity was monitored for a 1-h time period. Following sufficient time for recovery (minimum of 3 h post injection), cellular activity was monitored for an additional 15-min period. Both 1.0 and 1.5 g/kg ethanol potently suppressed the firing of hippocampal place-cells without altering place-field locations. Ethanol did not significantly suppress out-of-field firing rates, leading to a decrease in spatial specificity (i.e. the ratio of in-field/out-of-field firing rates). Interneuron activity was not altered by 1.0 g/kg ethanol, but was occasionally suppressed by 1.5 g/kg ethanol. Results are interpreted in light of recent behavioral and electrophysiological studies examining the effects of ethanol on hippocampal function. 相似文献
102.
103.
Objective: Using receiver operating characteristics (ROC) curve to evaluate the value of pulse wave velocity (PWV) in the diagnosis of coronary heart disease (CHD). Methods: By using coronary angiography as golden diagnostic standard of CHD, 218 patients were divided into both CHD group (n=121) and non-CHD group (n = 97). All these patients received PWV test. The efficacy of PWV of each artery segments in the diagnosis of CHD was evaluated by ROC curve. The sensitivity and specificity were calculated with the golden diagnostic standard of CHD. Results:The PWV of right carotid to femoral artery (Rc-f), left carotid to femoral artery (Lc-f), right radial to carotid artery (Rc-r), left radial to carotid artery (Lc-r) in CHD group were significantly higher than that of non-CHD group (9. 31±1. 75 vs 7.60±1.59, P<0. 01; 9. 02±1.71 vs 7. 52±1.50, P<0. 01; 8. 69±1. 37 vs 8. 00±1. 27, P<0. 01; 8.52±1. 03 vs 8. 03±1. 2, P<0. 01 respectively). However, the PWV of both right and left femoral to ankle artery (Rf-a and Lf-a) had no significant differences between the two groups. We then compared the area under curve (AUC) of each ROC(AUCROC) of PWV of Rc-f, Lc-f Rc-r and Lc-r to evaluate their diagnostic efficacy for CHD. We found that AUCROC of Rc-f PWV was the biggest (AUCROC = 0. 818), at the peak point of its ROC curve, the PWV was 8. 32 m/s. PWV>8. 32 m/s of Rc-f could predict the presence of CHD with a sensitivity of 79% and specificity of 77%. Conclusion: The PWV of Rc-f, Lc-f, Rc-r, Lc-r are significantly higher in CHD group than that in non-CHD group, and PWV of Rc-f is the most accurate in the detection of CHD. The PWV>8. 32 m/s of RC-F is a valuable predictor of CHD. 相似文献
104.
Patients seen in primary medical clinics report higher rates of major depression [Pérez-Stable et al., 1990: Arch Intern Med 15:1083-1088], and panic disorder [Sherbourne et al., 1996b: Von Korff et al., 1987: Arch Gen Psychiatry 44:152-156] than the general population. Primary care staff therefore need efficient methods of identifying patients with psychiatric disorders. The current study evaluates the use of several brief psychiatric screening measures for identifying patients with major depression and/or anxiety disorders. Participants were 213 primary care patients who received the Center for Epidemiological Studies Depression Scale (CES-D), the Beck Anxiety Inventory (BAI), and two new instruments, the Autonomic Nervous System Questionnaire (ANS) for assessing panic disorder and the Social Phobia Questionnaire (SPQ) for assessing social phobia. Participants received both the screening instruments and a structured diagnostic interview. Results suggest that the CES-D is a useful measure for detecting psychopathology, but it is not particularly specific to depression, the ANS was a highly sensitive and reasonably specific measure for panic disorder, and the SPQ was reasonably sensitive and specific for social phobia. The BAI was a relatively poor screening measure that added no significant information beyond the other measures. 相似文献
105.
高眼压症和青光眼患者角膜中央厚度的研究 总被引:1,自引:0,他引:1
李姝 《中国中医眼科杂志》2004,14(4):195-196
目的研究高眼压症和原发性开角型青光眼患者的角膜中央厚度(central corneal thickness,CCT),探讨CCT对Goldmann眼压计眼压测量的影响.方法分别用超声角膜测厚仪和Goldmann眼压计对原发性开角型青光眼病例18例36只眼和高眼压症患者15例26只眼以及正常对照组18例36只眼行角膜中央厚度和眼压(intraocular pressure,IOP)测量,并进行统计学分析.结果CCT在高眼压组为572.76±37.42(μm),原发性开角型青光眼组为548.41±34.15(μm),对照组为547.22±34.68(μm).高眼压组CCT值明显大于原发性开角型青光眼组和正常对照组,差异有显著性(P<0.05),CCT在后两组间差异不显著(P>O.05).46%的高眼压患者校正眼压正常.结论CCT是影响眼压测量的重要因素,诊断高眼压症的同时应该测量CCT. 相似文献
106.
复方沙棘颗粒对大鼠皮层神经细胞缺血性损伤的保护作用 总被引:1,自引:0,他引:1
目的 :研究复方沙棘颗粒对体外培养的大鼠大脑皮层神经细胞谷氨酸 (Glu)损伤的保护作用及机理。方法 :分离培养新生 (1d)大鼠大脑皮层神经细胞 ,加入Glu模拟兴奋性损伤 ,MTT法测定细胞存活率 ,比色法测定上清中乳酸脱氢酶 (LDH)含量 ,细胞中超氧化物歧化酶 (SOD)、谷胱甘肽 (GSH Px)活性、丙二醛 (MDA)含量。结果 :细胞经Glu损伤后 ,上清LDH含量、细胞中MDA含量显著增加 ,SOD和GSH Px活力明显下降。复方沙棘处理组可有效防止上述改变。结论 :复方沙棘颗粒可有效保护由Glu引起的大鼠大脑皮层神经细胞的损伤。其机理可能与抗脂质过氧化、清除自由基有关 相似文献
107.
采用方波溶出伏安法(OSWSV),建立了N-乙酰-5-羟色胺的—种新型快速、灵敏的测定体系。实验研究了富集条件、pH值对方波溶出伏安法对N-乙酰-5-羟色胺的影响。在pH=9.33的硼砂-氢氧化钠缓冲液中,N-乙酰-5-羟色胺在约0.2V(vs.Ag/AgCl)电位处产生一个阳极氧化峰,峰电流与浓度在1.0×10-7~1.0×10-4mol.L-1范围内成线性关系,N-乙酰-5-羟色胺检测限为1.2×10-8mol.L-1。进行尿样样品测定,回收率为81.8%,结果良好。 相似文献
108.
三种螺距对种植体初期稳定性影响的有限元研究 总被引:10,自引:2,他引:8
目的:利用即刻负载有限元模型,研究种植体不同螺纹螺距因素对初期稳定性的影响。方法:利用Pro/E软件、Hypermesh软件及ABAQUS有限元软件,建立四类种植体即刻负载的三维有限元模型,比较3种螺纹螺距(0.8mm、1.6mm、2.4mm)在分别垂直和水平加载时,对种植体初期稳定性的影响。结果:对不同螺纹螺距种植体来说,垂直加载和水平加载时0.8mm螺距螺纹种植体微动最小,2.4mm螺距螺纹种植体微动最大。结论:螺纹的螺距对垂直相对位移有影响,对水平相对位移影响不大。随着螺距的增加,种植体对抗垂直向载荷的抵抗力减弱。水平加载时,螺纹的螺距对颈部微动影响不明显。 相似文献
109.
Zhao Hu Feixiang Zhou Atipatsa Chiwanda Kaminga Huilan Xu 《Investigative ophthalmology & visual science》2022,63(5)
PurposeTo evaluate the potential causal associations between type 2 diabetes and fasting glucose and HbA1c levels and the risk of primary open-angle glaucoma (POAG) in European and East Asian populations.MethodsWe selected genetic variants (P < 5 × 10−8) for type 2 diabetes (898,130 Europeans; 433,540 East Asians), fasting glucose, and HbA1c (196,991 Europeans; 36,584 East Asians) from three meta-analyses of genome-wide association studies (GWAS). The GWAS for POAG provided summary statistics (192,702 Europeans; 46,523 East Asians). Mendelian randomization (MR) analysis was accomplished using the inverse variance–weighted method, weighted-median method, MR Egger method, and MR-Pleiotropy RESidual Sum and Outlier test.ResultsGenetically predicted type 2 diabetes was potentially positively associated with POAG in the European ancestry (body mass index [BMI]–unadjusted: odds ratio [OR] = 1.07, 95% confidence interval [CI], 1.01–1.14, P = 0.028; BMI-adjusted: OR = 1.07, 95% CI, 1.01–1.15, P = 0.035), but not in the East Asian ancestry (BMI-unadjusted: OR = 1.01, 95% CI, 0.95–1.06, P = 0.866; BMI-adjusted: OR = 1.00, 95% CI, 0.94–1.05, P = 0.882). There was no evidence to support a causal association of fasting glucose (European: OR = 1.19, P = 0.157; East Asian: OR = 0.94, P = 0.715) and HbA1c (European: OR = 1.27, P = 0.178; East Asian: OR = 0.85, P = 0.508) levels with POAG.ConclusionsThe causal effect of type 2 diabetes on the risk of POAG is different in European and East Asian populations. The point estimates of fasting glucose and Hb1Ac with POAG are large but not statistically significant, which prompts the question of statistical power. 相似文献
110.
Enshuai Wang Fei Yang Xinmin Shen Haiqin Duan Xiaonan Zhang Qin Yin Wenqiang Peng Xiaocui Yang Liu Yang 《Materials》2022,15(10)
An acoustic metamaterial absorber of parallel–connection square Helmholtz resonators is proposed in this study, and its sound absorption coefficients are optimized to reduce the noise for the given conditions in the factory. A two–dimensional equivalent simulation model is built to obtain the initial value of parameters and a three–dimensional finite element model is constructed to simulate the sound absorption performance of the metamaterial cell, which aims to improve the research efficiency. The optimal parameters of metamaterial cells are obtained through the particle swarm optimization algorithm, and its effectiveness and accuracy are validated through preparing the experimental sample using 3D printing and measuring the sound absorption coefficient by the standing wave tube detection. The consistency between the experimental data and simulation data verifies feasibility of the proposed optimization method and usefulness of the developed acoustic metamaterial absorber, and the desired sound absorption performances for given conditions are achieved. The experimental results prove that parallel–connection square Helmholtz resonators can achieve an adjustable frequency spectrum for the low frequency noise control by parameter optimization, which is propitious to promote its application in reducing the noise in the factory. 相似文献