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71.
72.
Steve Majerus Anne-Lise Leclercq Aurélie Grossmann Monique Touzin Martine Poncelet 《Cortex; a journal devoted to the study of the nervous system and behavior》2009,45(6):708-720
This study re-explored the nature of verbal short-term memory (STM) deficits in children with specific language impairment (SLI), by distinguishing item and serial order STM processes. Recent studies have shown serial order STM capacity to be a critical determinant of language development, relative to item STM. In Experiment 1, 12 children with SLI, 12 age-matched children and 12 language-matched children were administered serial order recognition and reconstruction tasks. Experiment 2 assessed implicit serial learning abilities via a Hebb learning task. The SLI group showed impaired performance for the serial order reconstruction and recognition tasks, relative to language-matched and/or age-matched control groups. However, normal serial position effects were observed in all SLI children in the serial order reconstruction task, suggesting normal coding of serial position information. Similarly, performance on the Hebb serial learning task was at chronological age appropriate levels. Experiment 3 showed that the group differences observed for the serial order STM tasks in Experiment 1 disappeared when the SLI group was compared to a mental age-matched control group. Experiment 4 showed similar performance levels in the SLI group and the mental age-matched control group for a nonword recognition task assessing item STM capacities. This study shows that children with SLI have no specific impairments for serial order and item STM components but that poorer general cognitive efficiency is related to functional limitations in verbal STM tasks. The data are in line with limited information processing accounts of SLI. 相似文献
73.
Age determines memory for face identity and expression 总被引:1,自引:1,他引:0
Egemen SAVASKAN Sandra Elisabeth MÜLLER reas BÖHRINGER Christine PHILIPPSEN Franz MÜLLER-SPAHN Hartmut SCHÄCHINGER 《Psychogeriatrics》2007,7(2):49-57
Background: The recognition of facial expressions is an important component of emotion processing which contributes to interactional behavior. One of the factors highly associated with potential decline of ability in behavioral tasks is age. Methods: We have investigated age‐related changes in facial identity and expression memory of healthy subjects in three age groups: young adults (20–40 years), elderly adults (60–80 years) and, for the first time in the literature, very old adults (over 80 years of age). Using a picture test, photographs of faces with happy or angry expressions were presented to study participants during the encoding task, and the memory for identity and emotional facial expression was investigated in a subsequent recognition task showing emotionally neutral faces. Half of the faces presented in the recognition task were initially shown in the encoding task. Results: Age interacted with the memory process: the ability to recognize both facial identity and emotional expression declined with advanced age. Happy facial expressions were better recognized in all age groups. Although there was a continuous overall decrease in recognition of both happy and angry expressions with advanced age, the effect favoring happy facial expressions was stable also in very old adults. Other factors such as gender or educational level did not affect the memory process for facial expressions. Conclusions: Our findings suggest that age is a significant determinant of memory for facial identity and emotional expression, and that, similar to younger adults, the recognition process of the elderly favors happy emotional facial expressions. 相似文献
74.
目的 测试复合矫治弓丝接头的机械性能及分析接头、接头断口变化。方法 测试复合矫治弓丝接头的拉伸强度、剪切强度、扭转强度、弯曲形变残余角,TiNi形状记忆合金丝超弹性,扫描电镜观察及分析接头、断口组织变化。结果 复合矫治弓丝接头抗拉伸强度为32 0~36 0MPa ,剪切强度为2 2 0~2 5 0MPa ,抗扭转强度为30~4 0N·m、断裂时扭转角度不小于1 4 4 0°,弯曲形变残余角为1 2~1 7°;钎焊异质接头中TiNi形状记忆合金丝超弹性几乎没有破坏;接头钎料与TiNi形状记忆合金界面不存在扩散层,与不锈钢丝界面之间有一较宽的扩散层,接头断裂多发生在钎料与TiNi形状记忆合金超弹界面处,部分发生在钎缝中心。结论 复合矫治弓丝机械性能符合正畸临床要求,可应用于临床。 相似文献
75.
他汀类药物对心血管的保护作用 总被引:6,自引:0,他引:6
他汀类药物(statins)被研制出来的最初目的是降低血脂,但是现在发现它不仅具有降低血脂的作用,还具有很多其他的作用包括改善内皮细胞功能的紊乱,提高内皮源性一氧化氮合成酶的生物活性,抑制血管平滑肌细胞的增殖,抗氧化作用,抗炎作用,降低血压,逆转心血管系统的重构。充分理解statins的多效性作用及机制有利于它更好的在临床中被应用于心血管系统的预防和治疗。 相似文献
76.
产科危重患者多器官功能障碍综合征的临床分析 总被引:4,自引:0,他引:4
目的 :分析产科危重患者多器官功能障碍综合征 (MODS)的发病特点及诱因 ,以及与急性生理与慢性健康状况评分II(APACHEII)的关系。方法 :回顾分析 2 0 0 0年1月至 2 0 0 4年 4月转入GICU产科危重患者中发生MODS 6 6例的临床资料 ,并计算其A PACHEII评分。结果 :产科MODS患者诱因主要是产科因素 ,共 4 8例 (72 .73% ) ,死亡 7例 (14 .5 8% ) ,以重度子痫前期或子痫及产后出血为主 ;诱因 18例妊娠合并内外科疾病 ,死亡 11例 ,死亡率为 6 1.11% ,以妊娠合并心脏病和妊娠合并重症肝炎为主。产科MODS患者死亡率随着器官损害数的增多而上升 ,差异有显著性 (P <0 .0 5 ) ;随着器官损害数的增多 ,APACHEII评分逐渐升高 ,差异有显著性 (P <0 .0 5 ) ;APACHEII评分用于预测MODS死亡阳性率 ,2 ,3,4 ,5个器官受损害 ,其阳性率分别为 33.4 5 % ,5 7.12 % ,97.0 9% ,10 0 %。结论 :产科多器官功能障碍 /衰竭的产科主要诱因是重度子痫前期 /子痫 ,产后出血 ;产科MODS患者死亡率也随着器官损害数的增多而上升 ;APACHEII评分可在一定程度上作为评定产科MODS患者病情危重程度和预测预后的指标。 相似文献
77.
623例慢性前列腺炎患者的性功能状况调查 总被引:6,自引:2,他引:4
目的:了解慢性前列腺炎对早泄(PE)和勃起功能障碍(ED)的影响,探讨它们之间的关系。方法:依据美国国立卫生研究院慢性前列腺炎症状指数评分表(NIH-CPSI)、中国早泄患者性功能评分表(C ISFPE)、国际勃起功能问卷评分表(IIEF-5);采用和患者面对面交谈、询问,并分别记录623例慢性前列腺炎患者的NIH-CPSI评分、C ISFPE评分、IIEF-5评分。结果:623例18~57岁的慢性前列腺炎患者中,PE发生率为39.0%,其中轻度占26.2%、中度占12.0%、重度占0.8%;ED发生率为16.9%,其中轻度占14.9%、中度占1.0%、重度占1.0%。慢性前列腺炎患者PE的发生率以年轻者为多,18~29岁组为42.9%(103/240)、30~39岁为37.0%(95/257)、40~57岁组为35.7%(45/126);ED发生率以年龄高者为多,18~29岁组为13.8%(33/240)、30~39岁为11.3%(29/257)、40~57岁组为34.1%(43/126)。统计学分析发现,NIH-CPSI评分与早泄评分以及与IIEF-5评分均无明显相关性。结论:慢性前列腺炎的症状轻重与PE和ED的轻重程度无明显的相关性。 相似文献
78.
J. de Rotrou L. Battal-Merlet E. Wenisch C. Chausson E. Bizet F. Dray H. Lenoir A.-S. Rigaud O. Hanon 《European journal of neurology》2007,14(2):144-149
Within the context of early diagnosis of Alzheimer's disease (AD), there is a growing interest in neuropsychological screening tests. Amongst these tests, we focused on the largely used Memory Impairment Screen (MIS). The objective of the present work was to show that adding a 10-min delayed recall to the MIS, improves the test psychometric characteristics in order to detect dementia in the earliest stages. A prospective study was carried out on a cohort of 270 consecutive elderly ambulatory subjects attending the Broca Hospital Memory Clinic: normal controls ( n = 67), mild cognitive impairment subjects ( n = 98) and mildly demented patients [ n = 105, Mini Mental State Examination (MMSE) = 23 ± 4]. This study consisted in testing the advantage of the 10-min delayed recall entitled MIS-D compared with the MIS. At a cut-off score of 6, the MIS-D revealed satisfying psychometric characteristics with a sensitivity of 81% and a specificity of 91%, whilst the MIS alone indicated a sensitivity of 60% and a specificity of 88% in detecting dementia. In demented patients with MMSE score ≥26, MIS-D properties still remained satisfying (sensitivity: 75%, specificity: 92%). MIS-D is a more relevant screening test than MIS alone at very early stages of dementia. 相似文献
79.
80.
Jiqu Xu Shuang Rong Bijun Xie Zhida Sun Li Zhang Hailei Wu Ping Yao Yunjian Zhang Liegang Liu 《Phytotherapy research : PTR》2009,23(12):1742-1747
The major purpose of this study was to determine the effect of procyanidins extracted from the lotus seedpod (LSPC) on the learning and memory impairments induced by scopolamine (1 mg/kg, i.p.) in mice. The capacities of memory and learning were evaluated by the Morris water maze and the step‐down avoidance test. LSPC (50, 100, 150 mg/kg BW, p.o.) significantly reversed scopolamine‐induced learning and memory impairments in the Morris water maze test, as evaluated by shortened escape latency and swimming distance. In the step‐down avoidance test, LSPC (50, 100, 150 mg/kg BW, p.o.) treatment significantly reduced the number of errors and shortened latency compared with that of scopolamine. In addition, LSPC was also found to inhibit acetyl cholinesterase (AChE) activity. These results of this study suggest that LSPC may play a useful role in the treatment of cognitive impairment caused by AD and aging. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献