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101.
目的: 探讨多种油脂肪乳剂对超未成熟儿肝脏功能的影响。方法: 回顾分析2015年7月1日至2021年6月30日收治的胎龄<28周、接受肠外静脉营养超过2周的超未成熟儿60例。根据应用脂肪乳剂种类不同,分为SMOF (多种油脂肪乳)组(n=30),和LCT (长链脂肪乳)组(n=30)。比较2组DBIL、ALT、γ-GT、TBA达峰值的指标及胃肠外营养相关性胆汁淤积(PNAC)发病率。结果: LCT组DBIL、ALT、γ-GT、TBA峰值均数分别为25.7(6.5~223)μmol·L-1、(52.5±44.7) U·L-1、(204.9±74.7) U·L-1、(64.9±48.6)μmol·L-1,SMOF组DBIL、ALT、γ-GT、TBA峰值均数分别为15.1(5.2~167.7)μmol·L-1、(32.5±18.8) U·L-1、(176.9±74.7) U·L-1、(53.3±35.8)μmol·L-1,其中2组DBIL、ALT峰值比较,P分别为0.026及0.034,差异均有统计学意义。2组γ-GT、TBA峰值比较差异无统计学意义。LCT组PNAC发生率为40%,SMOF组PNAC发生率为16.7%,2组比较差异有统计学意义(P=0.042)。结论: 与LCT比较,SMOF能减轻超未成熟儿DBIL、GOT、γ-GT、TBA的严重程度,并降低PNAC的发生率,对肝脏有一定的保护作用。 相似文献
102.
Isabela Pedroza-Pacheco Alejandro Madrigal Aurore Saudemont 《Cellular & molecular immunology》2013,10(3):222-229
Regulatory T (Treg) cells and natural killer (NK) cells are key players in the immune system. The interaction between these two cell types has been reported to be beneficial in healthy conditions such as pregnancy. However, in the case of certain pathologies such as autoimmune diseases and cancer this interaction can become detrimental, as Treg cells have been described to suppress NK cells and in particular to impair NK cell effector functions. This review aims to discuss the recent information on the interaction between Treg cells and NK cells under healthy and pathologic conditions, to describe the specific conditions in which this interaction takes place, the effect of Treg cells on hematopoietic stem cell differentiation and the consequences of this interaction on the optimization of immunotherapeutic protocols. 相似文献
103.
Amphetamine-Induced Dopamine Release and Neurocognitive Function in Treatment-Naive Adults with ADHD
Mariya V Cherkasova Nazlie Faridi Kevin F Casey Gillian A O'Driscoll Lily Hechtman Ridha Joober Glen B Baker Jennifer Palmer Alain Dagher Marco Leyton Chawki Benkelfat 《Neuropsychopharmacology》2014,39(6):1498-1507
Converging evidence from clinical, preclinical, neuroimaging, and genetic research implicates dopamine neurotransmission in the pathophysiology of attention deficit hyperactivity disorder (ADHD). The in vivo neuroreceptor imaging evidence also suggests alterations in the dopamine system in ADHD; however, the nature and behavioral significance of those have not yet been established. Here, we investigated striatal dopaminergic function in ADHD using [11C]raclopride PET with a d-amphetamine challenge. We also examined the relationship of striatal dopamine responses to ADHD symptoms and neurocognitive function. A total of 15 treatment-free, noncomorbid adult males with ADHD (age: 29.87±8.65) and 18 healthy male controls (age: 25.44±6.77) underwent two PET scans: one following a lactose placebo and the other following d-amphetamine (0.3 mg/kg, p.o.), administered double blind and in random order counterbalanced across groups. In a separate session without a drug, participants performed a battery of neurocognitive tests. Relative to the healthy controls, the ADHD patients, as a group, showed greater d-amphetamine-induced decreases in striatal [11C]raclopride binding and performed more poorly on measures of response inhibition. Across groups, a greater magnitude of d-amphetamine-induced change in [11C]raclopride binding potential was associated with poorer performance on measures of response inhibition and ADHD symptoms. Our findings suggest an augmented striatal dopaminergic response in treatment-naive ADHD. Though in contrast to results of a previous study, this finding appears consistent with a model proposing exaggerated phasic dopamine release in ADHD. A susceptibility to increased phasic dopamine responsivity may contribute to such characteristics of ADHD as poor inhibition and impulsivity. 相似文献
104.
We aimed to compare executive function (EF) outcomes in pediatric brain tumor (BT) survivors compared with healthy children (HC) across multiple settings. This retrospective cross-sectional study of BT survivors and age- and gender-matched HC analyzed scale patterns of parent and teacher ratings of EF (Behavior Ratings of Executive Function; BRIEF). We also analyzed relationships between groups and raters (parent/teacher) and clinical elevations across EF domains on the BRIEF. Group differences in aspects of EF emerged from parent ratings in working memory (WM), while significant interactions from teacher ratings emerged on nearly all EF scales. Parents reported impaired cognitive/behavioral flexibility in the BT group four times more than parents of HC. Teachers rated survivors significantly more poorly as a group on the majority of EF domains, and indicated clinical impairment in cognitive/behavioral flexibility, emotional regulation, self-starting/initiation, WM, and planning and organization (P/O) four to ten times more often than the teachers of HC. Overall, teacher ratings of EF impairment in pediatric BT survivors were significantly greater than parent ratings, who reported far fewer EF problems. Possible explanations for inter-rater discrepancies include potential reporting bias/response shift in parents and/or differences in EF demands across settings. 相似文献
105.
《Brain stimulation》2014,7(6):773-783
BackgroundTranscranial direct current stimulation (tDCS) is increasingly used in research and clinical settings, and the dorsolateral prefrontal cortex (DLPFC) is often chosen as a target for stimulation. While numerous studies report modulation of cognitive abilities following DLPFC stimulation, the wide array of cognitive functions that can be modulated makes it difficult to predict its precise outcome.ObjectiveThe present review aims at identifying and characterizing the various cognitive domains affected by tDCS over DLPFC.MethodsArticles using tDCS over DLPFC indexed in PubMed and published between January 2000 and January 2014 were included in the present review.ResultstDCS over DLPFC affects a wide array of cognitive functions, with sometimes apparent conflicting results.ConclusionPrefrontal tDCS has the potential to modulate numerous cognitive functions simultaneously, but to properly interpret the results, a clear a priori hypothesis is necessary, careful technical consideration are mandatory, further insights into the neurobiological impact of tDCS are needed, and consideration should be given to the possibility that some behavioral effects may be partly explained by parallel modulation of related functions. 相似文献
106.
Jérémy Besnard Philippe Allain Ghislaine Aubin Valérie Chauviré Frédérique Etcharry-Bouyx Didier Le Gall 《Journal of clinical and experimental neuropsychology》2014,36(1):88-109
Introduction: A. R. Luria was the first author to hypothesize that executive dysfunction can lead to specific deficits in arithmetic problem solving, showing that patients’ performance depends on the structure of the tasks. Cummings (1995. Anatomic and behavioral aspects of frontal-subcortical circuits. Annals of the New York Academy of Sciences, 15, 1–13) proposed the term “environmental dependency” to define such behavioral disorders triggered by the characteristics of the test and pointed out also the role of executive impairments. Few studies compare executive functioning and problem solving in brain-damaged patients, and none have examined the question from this point of view. Thus, the main aim of the present paper was to study the relationship between environmental dependency and executive functions. Method: Fifty neurological patients with frontal, subcortical, and posterior brain lesions were compared to 45 matched healthy controls and were divided into two groups (dysexecutive/nondysexecutive) according to their performances on executive tasks. Then, we confronted the results of the two groups on an experimental protocol designed in accordance with Luria’s proposals. We made also comparisons between groups on the basis of lesion location. Results: Our findings indicate a high association between executive functions and environmental dependency, showing that dysexecutive patients’ performances were dependent on task demands. In addition, a specific frontal behavior not associated with executive functions and characterized by the solving of insoluble problems was highlighted. Conclusion: The discussion focused on the interest to take into account the methodological and clinical contributions of environmental dependency. Based on our findings and theoretical arguments, we highlight the need to fractionate this concept. 相似文献
107.
108.
《Revue neurologique》2014,170(8-9):527-530
The commonly used test to evaluate naming ability in multiple sclerosis (MS) is the Boston Naming Test (BNT). In previous studies the BNP has not shown any specific deficit in MS patients. The BNT score is obtained by adding spontaneously correct answers to correct answers obtained after semantic and phonological clues are given. Our hypothesis was that due to a lexical access deficit based on executive dysfunction, MS patients would need more clues than control subjects to normalize their performances,. Fifteen relapsing-remitting (RR) and 17 secondary progressive (SP) MS patients, and 32 controls matched for sex, age, and educational level, took the BNT. The 32 MS patients also took the BCCog (Short French battery used in MS to evaluate cognitive functions) in order to evaluate their executive functions. MS patients needed significantly more clues than matched controls to normalize their performances (P < 0.001). This lexical access deficit was more frequent in the SP than in the RR group (P < 0.05). A lexical access deficit inducing a denomination problem has thus been shown in MS patients. Further research should aim to better evaluate the executive functions of patients with a lexical access deficit. 相似文献
109.
《Parkinsonism & related disorders》2014,20(12):1359-1364
BackgroundFreezing of gait (FOG) is a major concern for Parkinson's disease (PD) patients because it is a leading cause of falls and is associated with poor quality of life. The pathophysiology is unknown but it is hypothesized that it relates to cognitive abnormalities; particularly executive and visuospatial dysfunction. However, prior results have been discrepant. Pharmacologic subtypes of FOG include those that are responsive and unresponsive to levodopa.ObjectiveTo determine whether executive and visuospatial dysfunction are associated specifically with the levodopa unresponsive subtype of FOG.Methods135 PD subjects completed a single assessment included FOG questionnaire, UPDRS motor scale, comprehensive cognitive battery and measure of hallucinations. Analyses compared unresponsive (n = 16), responsive (n = 20) and no FOG (n = 99) subtypes.ResultsThe unresponsive subtype had a significantly older age of onset of PD than the responsive group (p = .03) and had worse motor scores (p = .003) than the no FOG group. Longer disease duration was associated with the responsive group compared to the no FOG group (p = .002). The unresponsive FOG group had significantly poorer visuospatial ability (p = .001) and executive functioning (p = .02) than both the no and responsive FOG subgroups. These latter groups were not significantly different. The responsive FOG group was associated with the presence of hallucinations.ConclusionAside from pharmacological differences, unresponsive FOG is associated with executive and visuospatial dysfunction implicating frontostriatal pathways while responsive FOG is associated with hallucinations suggesting involvement of posterior cortical regions. Further study and treatment of FOG should include appropriate subtype classification. 相似文献
110.
The study investigated, with an adult sample, the hypothesis that differences between subtypes of ADHD on neuropsychological tests contribute to the poor separation of ADHD and healthy groups on tests of this kind. Groups of ADHD inattentive (n = 16) and combined (n = 16) subtypes were carefully identified using DSM-IV criteria, and their performance on 14 measures of attention, memory, and executive function (EF) was compared between subtypes and between the two subtypes combined and a group of healthy controls (n = 30). Multivariate analyses showed statistically significant differences between the two subtypes, and between the two subtypes combined and the healthy controls. Importantly for the hypothesis, where differences for neuropsychological tests in terms of effect sizes between subtypes were largest, the differences in effect sizes between the two groups combined and controls were smallest (r = −0.64, 95% CI [−0.15, −0.87]). 相似文献