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971.
ObjectiveTo assess the importance of the Pelli-Robson contrast sensitivity test in multiple sclerosis patients according to the Expanded Disability Status Scale (EDSS).Material and methodsA total of 62 patients with multiple sclerosis were included in a retrospective study. Patients were enrolled from the Neurology Department to Neuroophthalmology at Virgen de la Victoria Hospital. Patients were classified into 3 groups according to EDSS: group A) lower than 1.5, group B) between 1.5 and 3.5 and group C) greater than 3.5. Visual acuity and monocular and binocular contrast sensitivity were performed with Snellen and Pelli-Robson tests respectively. Twelve disease-free control participants were also recruited. Correlations between parameter changes were analyzed.ResultsThe mean duration of the disease was 81.54 ± 35.32 months. Monocular and binocular Pelli-Robson mean values in the control group were 1.82 ± 0.10 and 1.93 ± 0.43 respectively, and 1.61 ± 0.29 and 1.83 ± 0.19 in multiple sclerosis patients. There were statistically significant differences in the monocular analysis for a level of significance P<.05. Mean monocular and binocular Pelli-Robson values in relation to gravity level were, in group A: 1.66 ± 0.24 and 1.90 ± 0.98, group B: 1.64 ± 0.21 and 1.82 ± 0.16, and group C: 1.47 ± 0.45 and 1.73 ± 0.32 respectively. Group differences were statistically significant in both tests: P=.05 and P=.027.ConclusionsMonocular and binocular contrast discrimination analyzed using the Pelli-Robson test was found to be significantly lower when the severity level, according EDSS, increases in multiple sclerosis patients.  相似文献   
972.
目的 比较SHR、WKY、SD大鼠行为学特征,探寻研究SHR大鼠注意缺陷多动障碍(ADHD)理想的对照模型。方法 运用旷场实验统计大鼠运动距离、运动速度、穿格数及理毛次数来评价SHR、WKY、SD大鼠自主运动情况;运用水迷宫实验检测三组大鼠的学习记忆能力。结果 旷场实验结果显示,SHR大鼠在总运动量、平均运动速度及穿格次数上较WKY及SD大鼠均显著增加(P<0.01);与WKY大鼠相比,SD大鼠运动距离显著高于WKY组(P<0.01),其运动速度及穿格数略高于WKY组(P<0.05);水迷宫隐匿站台实验中,与SHR大鼠相比,SD大鼠潜伏期较长(P<0.05),在潜伏期运动距离上,SD大鼠在训练第1天、第3天及第4天运动距离较SHR大鼠延长(P<0.05或P<0.01);比较WKY组,SD大鼠潜伏期及潜伏期运动距离较WKY在各个训练时间均有不同程度的下降(P<0.05或P<0.01)。在空间探索阶段,SD大鼠穿台次数及目标象限运动时间、距离比率等均较SHR大鼠有所减少(P<0.05),而较WKY大鼠则有不同程度的升高(P<0.05或P<0.01)。结论 WKY大鼠与SHR大鼠行为学差异过大,两者的比较存在一定的不足,增设SD大鼠作为SHR大鼠的对照组能够提升SHR大鼠行为学特征的可比性,更为客观的反映SHR大鼠的行为学特征。  相似文献   
973.
974.
Nonsuicidal self-injury (NSSI) is associated with reduced pain sensitivity (PS). Existing theories posit that altered PS is a risk factor for NSSI. Cross-sectional data suggest that PS normalizes in those terminating self-injury. However, previously no study addressed the longitudinal course of PS in patients engaging in NSSI. We addressed changes in PS and clinical symptomatology in adolescents with NSSI (n = 18) and matched controls (n = 19) over one year. Despite significant clinical improvements, PS did not change in the NSSI group but decreased in controls. Greater NSSI reduction was associated with increased pain tolerance. Findings are discussed in the light of current theories on PS in NSSI.  相似文献   
975.
For biological and statistical reasons it makes sense to combine information from variants at the level of the gene. One may wish to give more weight to variants which are rare and those that are more likely to affect function. A combined weighting scheme, implemented in the SCOREASSOC program, was applied to whole exome sequence data for 1392 subjects with schizophrenia and 982 with obesity from the UK10K project. Results conformed fairly well with null hypothesis expectations and no individual gene was strongly implicated. However, a number of the higher ranked genes appear plausible candidates as being involved in one or other phenotype and may warrant further investigation. These include MC4R, NLGN2, CRP, DONSON, GTF3A, IL36B, ADCYAP1R1, ARSA, DLG1, SIK2, SLAIN1, UBE2Q2, ZNF507, CRHR1, MUSK, NSF, SNORD115, GDF3 and HIBADH. Some individual variants in these genes have different frequencies between cohorts and could be genotyped in additional subjects. For other genes, there is a general excess of variants at many different sites so attempts at replication would be more difficult. Overall, the weighted burden test provides a convenient method for using sequence data to highlight genes of interest.  相似文献   
976.
Sensitivity to interaural time differences (ITDs) is important for sound localization. Normal-hearing listeners benefit from across-frequency processing, as seen with improved ITD thresholds when consistent ITD cues are presented over a range of frequency channels compared with when ITD information is only presented in a single frequency channel. This study aimed to clarify whether cochlear-implant (CI) listeners can make use of similar processing when being stimulated with multiple interaural electrode pairs transmitting consistent ITD information. ITD thresholds for unmodulated, 100-pulse-per-second pulse trains were measured in seven bilateral CI listeners using research interfaces. Consistent ITDs were presented at either one or two electrode pairs at different current levels, allowing for comparisons at either constant level per component electrode or equal overall loudness. Different tonotopic distances between the pairs were tested in order to clarify the potential influence of channel interaction. Comparison of ITD thresholds between double pairs and the respective single pairs revealed systematic effects of tonotopic separation and current level. At constant levels, performance with double-pair stimulation improved compared with single-pair stimulation but only for large tonotopic separation. Comparisons at equal overall loudness revealed no benefit from presenting ITD information at two electrode pairs for any tonotopic spacing. Irrespective of electrode-pair configuration, ITD sensitivity improved with increasing current level. Hence, the improved ITD sensitivity for double pairs found for a large tonotopic separation and constant current levels seems to be due to increased loudness. The overall data suggest that CI listeners can benefit from combining consistent ITD information across multiple electrodes, provided sufficient stimulus levels and that stimulating electrode pairs are widely spaced.  相似文献   
977.
Purpose: To compare early visual function between patients undergoing phacoemulsification combined with multifocal and accommodative intraocular lens implantation.
Methods: A total of 112 patients with age-related cataract undergoing phacoemulsification in our hospital were recruited for this study and randomly assigned into multifocal (56 eyes; ZAM00 group) and accommodative (56 eyes; FLEX group) intraocular lens groups. Visual acuity and contrast sensitivity were statistically compared between the two groups.
Results: No significant difference was found in uncorrected distant visual acuity between the ZMA00 and FLEX groups at 1 week, or 1, 3, and 6 months after operation (all P〉0.05). At postoperative 6 months, no statistical significance was noted in distant and intermediate best-corrected visual acuity or in contrast sensitivity between the two groups (all P〉0.05). Patients in the ZMA00 group were superior to their counterparts in the FLEX group regarding near best corrected visual acuity, reading speed, and spectacle independence (all P〈0.05).
Conclusion: ZMA00 and FLEX IOL implantation can provide excellent distant and intermediate visual acuity for patients with age-related cataract. ZMA00 IOL is superior to FLEX in terms of near visual acuity.  相似文献   
978.
979.
980.
目的本课题观察急性冠脉综合征(ACS)患者中超敏c反应蛋白(hs—CRP)及血脂水平变化,评价hs—CRP与ACS的关系。方法随机入选ACS患者81例,其中不稳定心绞痛(UAP)47倒,急性心肌梗塞(AMI)34例,入选稳定性心绞痛(SAP)24例。于发病12—24小时分别测定hs—CRP及血脂水平。另设正常健康对照组20例与之对照。结果AMI组、UAP组及SAP组三组血清hs—CRP水平及血清总胆固醇、甘油三酯、低密度脂蛋白胆固醇水平均较健康对照组显著增高(P〈0.05.0.001),血清高密度脂蛋白胆固醇水平显著降低(P〈0.05)。结论hs—cRP可能与ACS发病有关,ACS患者测定hs—CRP浓度可为临床评价痛情的变化提供有意义的参考指标,临床在治疗时应充分考虑炎症反应这一危险因素。  相似文献   
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