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1.
Background: Traumatic brain injury (TBI) results in verbal recall deficits and impaired processing of emotion encoded in facial appearance, prosody and the linguistic content of messages. Emotion facilitates memory (emotional memory advantage) for non-brain injured (NBI) individuals but the impact of emotion on verbal recall for linguistically encoded stimuli in TBI has not been explored.

Aims: The purpose of this study was to determine the effects of stimulus emotional content on verbal recall of words and paragraphs in TBI compared to NBI individuals.

Methods and procedures: Six 10-item lists, each with five emotional and five neutral words, and six paragraphs (three emotional, three neutral) were counterbalanced and presented in random order to 20 individuals with TBI and 44 NBI. The number of words from lists and the number of content units from paragraphs were compared for the two groups.

Outcomes and results: The NBI participants recalled more words from the lists and content units from the paragraphs than the individuals with TBI. Both groups recalled significantly more emotional than neutral words. NBI but not TBI participants had significantly greater recall for information in paragraphs with emotional content.

Conclusions: Participants with TBI showed impaired recall of words and paragraph content. Emotion facilitated word and paragraph content recall for neurotypical individuals but emotional memory advantage was limited to words for the TBI participants.  相似文献   

2.
Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can be reinstated by a non‐invasive multisensory training procedure in which spatiotemporally concordant visual‐auditory pairs are repeatedly presented within the blind hemifield. Despite this recovery of visual responsiveness, the loss of visual cortex was expected to result in permanent deficits in that hemifield, especially when visual events in both hemifields compete for attention and access to the brain's visuomotor circuitry. This was evaluated in the present study in a visual choice paradigm in which the two visual hemifields of recovered cats were simultaneously stimulated with equally valent visual targets. Surprisingly, the expected disparity was not found, and some animals even preferred stimuli presented in the previously blind hemifield. This preference persisted across multiple stimulus intensity levels and there was no indication that animals were less aware of cues in the previously blind hemifield than in its spared counterpart. Furthermore, when auditory cues were combined with visual cues, the enhanced performance they produced on a visual task was no greater in the normal than in the previously blind hemifield. These observations suggest that the multisensory rehabilitation paradigm revealed greater inherent visual information processing potential in the previously blind hemifield than was believed possible given the loss of visual cortex.  相似文献   
3.
在军队物资非招标采购方式运用实践中,竞争性谈判采购存在竞争性程度问题、谈判操作中的严密性问题、临时更改评审方法标准和成交条件问题;询价采购存在评审方法和评定成交的标准问题、是否必须有3家以上合格报价问题、指定品牌问题和其他程序问题;单一来源采购存在价格居高不下问题、成本价格随性能同时增长问题、技术创新与技术改造的动力受限问题.  相似文献   
4.
5.
为了识别在不同思维状态下的自发脑电(EEG)信号,本文用6阶自回归(AR)模型表示EEG信号,用学习矢量量化(LVQ)神经网络作分类器,分别用LVQl和LVQ2.1算法对网络进行训练,并对分类结果进行测试,比较了网络选择不同参数时对分类正确率的影响。研究表明:竞争层神经元数目直接影响了正确率,当选择最佳参数值时分类正确率为62%-83%,因人而异。  相似文献   
6.
文章阐述了我国医药制造业的基本现状,对31个省市区(港、澳、台地区除外)的医药制造业竞争力,主要从市场占有率和市场竞争优势系数两个方面,进行了比较分析。市场占有率的优势主要集中在东部发达地区,但是市场竞争优势系数的优势分布较为均匀,各地区均有其自身的优势。  相似文献   
7.
Thirty randomly oriented T’s were presented in a circle around fixation at an eccentricity of 11° such that each T was crowded by its neighbors. Two locations within the same hemifield (unilateral condition) or one location in each hemifield (bilateral condition) were precued for subsequent probing. Observers were then asked to report the orientation of a target T at one of these locations. A bilateral field advantage was found: target identification was better when the two precued targets were in different hemifields than when they were within the same hemifield. This bilateral advantage was absent when only targets were presented, without any distracters. Further controls showed that this advantage could not be attributed to differences between horizontal and vertical target alignments or to visual field anisotropies. A similar bilateral advantage has been reported for multiple object tracking (Alvarez, G. A., & Cavanagh, P. (2005). Independent resources for attentional tracking in the left and right visual fields. Psychological Science 16(8), 637-643) and other attentional tasks. Our results suggest that crowding also demonstrates separate attentional resources in the left and right hemifields. There was a cost to attending to two targets presented unilaterally over attending to a single target. However, this cost was reduced when the two crowded targets were in separate hemifields.  相似文献   
8.
Virgin males (or females) of some species ofDrosophila, when stored singly, are known to be superior in mating to males (or females) stored in groups. This may create a spurious rare-male effect on some occasions. When no account is taken of this storage effect in an experimental setup designed to show rare-male mating advantage, bias in favor of a raremale effect may result. It is shown that merely by storing the rare males singly and the common males in groups, with males not differing in any other respect, a very strong spurious rare-male effect can be produced. Similarly, it is shown that a spurious rare-female effect is possible too. It is proposed that the very strong rare-male effect for pepperment scent as found by Dal Molin [(1979).Am. Nat. 113:951–954] is merely a result of such a bias. The relevance for natural populations of the mating advantage associated with the single housing condition is discussed. In the experiments designed to show a spurious rare-male effect, mating chambers of two different sizes were used. It is shown that sexual selection is more severe in the small chambers, for both males and females.  相似文献   
9.
Cytokines serve a central function as key factors in the regulation of the intestinal immune response and mediation of tissue damage in inflammatory bowel disease (IBD). Abnormalities in the expression of immunoregulatory cytokines such as IL-2, IL-4, IL-10 and interferon-gamma (IFN-gamma) may indicate a dysregulation of intestinal immunity probably associated with pathogenic events. Therefore, cytokine mRNA concentrations were determined in the mucosa of patients with IBD at sites of active (n = 13) and inactive (n = 12) ulcerative colitis (UC), active (n = 11) and inactive (n = 11) Crohn's disease (CD) and in control patients (n = 14) using quantitative RT-PCR. IL-10 mRNA concentrations were significantly increased in patients with both active UC (P < 0.001) and active CD (P < 0.005) compared with control patients. IFN-gamma mRNA concentrations were also significantly increased both in patients with active UC (P < 0.02) and active CD (P < 0.05) compared with control patients, whereas IL-2 mRNA levels were significantly (P < 0.02) increased only in active CD. IL-4 mRNA expression in the intestinal mucosa was frequently below the detection limit. Our results demonstrate that chronic intestinal inflammation in patients with CD is characterized by an increase of Th1-like cytokines. Furthermore, the increased IL-10 mRNA expression at sites of active IBD suggests that IL-10 is an important regulatory component involved in the control of the inflammatory response in inflammatory bowel disease.  相似文献   
10.
Induction of ovulation after gnRH antagonists   总被引:2,自引:0,他引:2  
The gonadotrophin-releasing hormone (GnRH) antagonist binds competitively to the receptors and thereby prevents endogenous GnRH from exerting its stimulatory effect on the pituitary cells. This causes suppression of gonadotrophin secretion which occurs immediately after administration of the antagonist. When using GnRH antagonist in controlled ovarian stimulation, ovulation or maturation of the oocyte can, therefore, be induced by a variety of drugs, e.g. native GnRH, recombinant LH or short-acting GnRH agonists. Short-acting GnRH agonists were recommended for triggering ovulation in cases with a high risk of developing ovarian hyperstimulation syndrome (OHSS). Since it is evident that GnRH is required to initiate the LH surge and the oestradiol rise, a single administration of GnRH antagonist during the late follicular phase delays the LH surge. Studies showed that a single s.c. administration of 3 or 5 mg of Cetrorelix in the late follicular stage was sufficient to prevent the LH surge for 617 days. This phenomenon can be used in high responder patients who are prone to OHSS. The question whether this delay has any effect on oocyte quality and maturation still remains unanswered. Overall, there are four uses for GnRH antagonist: (i) using short-acting GnRH agonists for triggering ovulation in cases in which the GnRH antagonist is part of the protocol for ovarian stimulation. Recombinant LH and native LHRH could also be used as triggers of LH surge; (ii) delaying the LH surge in cases prone to OHSS by treatment with GnRH antagonist; (iii) to administer GnRH antagonist during the luteal phase to decrease the activity of corpora lutea; (iv) in polycystic ovarian disease with elevated LH the LH/FSH ratio can be corrected with the injection of GnRH antagonist prior to and during ovarian stimulation.  相似文献   
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