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31.
Endogenous circadian rhythms prepare the cardiovascular (CV) system for optimal function to match the daily anticipated behavioral and environmental cycles, including variable activities when awake during the day and recuperation when sleeping at night. The overall day-night patterns in most CV variables result from the summation of predictable circadian effects with variable behavioral and environmental effects on the CV system. The circadian system has also been implicated in the morning peak in the incidence of adverse CV events, including myocardial infarction, stroke, and sudden cardiac death. We discuss the resting and stress-reactive circadian control of CV physiology in humans and suggest future research opportunities, including improving CV therapy by optimally timing therapy relative to a person’s internal body clock time.  相似文献   
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In this paper, the properties of Amari’s dynamical neural field with global constant inhibition induced by its kernel are investigated. Amari’s dynamical neural field illustrates many neurophysiological phenomena successfully and has been applied to unsupervised learning like data clustering in recent years. In its applications, the stationary solution to Amari’s dynamical neural field plays an important role that the underlying patterns being perceived are usually presented as the excited region in it. However, the type of stationary solution to dynamical neural field with typical kernel is often sensitive to parameters of its kernel that limits its range of application. Different from dynamical neural field with typical kernel that have been discussed a lot, there are few theoretical results on dynamical neural field with global constant inhibitory kernel that has already shown better performance in practice. In this paper, some important results on existence and stability of stationary solution to dynamical neural field with global constant inhibitory kernel are obtained. All of these results show that such kind of dynamical neural field has better potential for missions like data clustering than those with typical kernels, which provide a theoretical basis of its further extensive application.  相似文献   
34.
Deficits in the capacity to engage in social interactions are a core deficit associated with Autistic Disorder (AD) and Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS). These deficits emerge at a young age, making screening for social interaction deficits and interventions targeted at improving capacity in this area important for early identification and intervention. Screening and early intervention efforts are particularly important given the poor short and long term outcomes for children with Autism Spectrum Disorders (ASDs) who experience social interaction deficits. The Screen for Social Interaction (SSI) is a well-validated screening measure that examines a child's capacity for social interaction using a developmental approach. The present study identified four underlying factors measured by the SSI, namely, Connection with Caregiver, Interaction/Imagination, Social Approach/Interest, and Agreeable Nature. The resulting factors were utilized to compare social interaction profiles across groups of children with AD, PDD-NOS, children with non-ASD developmental and/or psychiatric conditions and typically developing children. The results indicate that children with AD and those with PDD-NOS had similar social interaction profiles, but were able to be distinguished from typically developing children on every factor and were able to be distinguished from children with non-ASD psychiatric conditions on every factor except the Connection with Caregiver factor. In addition, children with non-ASD developmental and/or psychiatric conditions could be distinguished from typically developing children on the Connection with Caregiver factor and the Social Approach/Interest factor. These findings have implications for screening and intervention for children with ASDs and non-ASD psychiatric conditions.  相似文献   
35.
"心肾相交"是指肾水上济于心,心火下降于肾。Klotho作为肾精的物质基础,在生理功能上与肾精作用相同,二者均秉承于父母,具有抗衰老、主生殖和生长发育、保护骨骼调节钙磷代谢等功用。Klotho衍生物可溶性Klotho(soluble Klotho,sKlotho)延续了Klotho的生理功能,并参与调节心肌细胞和血管平滑肌细胞的钙离子代谢,抑制钙离子沉积,调节脉道,保护心血管,具有交通心藏系统的功能。Klotho基因的这种微观调节作用,使得心藏系统和肾藏系统之间的关系更加紧密,加强了中医心肾之间的交互关系,也丰富了中医"心肾相交"理论。  相似文献   
36.
Several learning approaches have been used to predict RNA-binding amino acids in a protein sequence, but there has been little attempt to predict protein-binding nucleotides in an RNA sequence. One of the reasons is that the differences between nucleotides in their interaction propensity are much smaller than those between amino acids. Another reason is that RNA exhibits less diverse sequence patterns than protein. Therefore, predicting protein-binding RNA nucleotides is much harder than predicting RNA-binding amino acids. We developed a new method that removes data redundancy in a training set of sequences based on their features. The new method constructs a larger and more informative training set than the standard redundancy removal method based on sequence similarity, and the constructed dataset is guaranteed to be redundancy-free. We computed the interaction propensity (IP) of nucleotide triplets by applying a new definition of IP to an extensive dataset of protein-RNA complexes, and developed a support vector machine (SVM) model to predict protein binding sites in RNA sequences. In a 5-fold cross-validation with 812 RNA sequences, the SVM model predicted protein-binding nucleotides with an accuracy of 86.4%, an F-measure of 84.8%, and a Matthews correlation coefficient of 0.66. With an independent dataset of 56 RNA sequences that were not used in training, the resulting accuracy was 68.1% with an F-measure of 71.7% and a Matthews correlation coefficient of 0.35. To the best of our knowledge, this is the first attempt to predict protein-binding RNA nucleotides in a given RNA sequence from the sequence data alone. The SVM model and datasets are freely available for academics at http://bclab.inha.ac.kr/primer.  相似文献   
37.
This preliminary study presents the results of a process of validation of a new questionnaire on the type of interaction in the game (QTIJV), composed of 26 items. This instrument focuses on two types of interaction: emotional and sensory-motor-narrative. It aims to distinguish use “normal” use “problem” video game. To this end, 313 adolescents aged 11 to 18 years, were surveyed in schools in the Île-de-France and Amiens. The results show good psychometric qualities of the tool (factor structure, internal consistency, Bravais Pearson correlation coefficient and concordance test/retest sensitivity, internal validity and reliability) with a confirmatory factor analysis proposing a new theoretical model of adjustment seven factors.  相似文献   
38.
Sensemaking theories help designers understand the cognitive processes of a user when he/she performs a complicated task. This paper introduces a two-step approach of incorporating sensemaking support within the design of health information systems by: (1) modeling the sensemaking process of physicians while performing a task, and (2) identifying software interaction design requirements that support sensemaking based on this model. The two-step approach is presented based on a case study of the tumor contouring clinical task for radiotherapy planning. In the first step of the approach, a contextualized sensemaking model was developed to describe the sensemaking process based on the goal, the workflow and the context of the task. In the second step, based on a research software prototype, an experiment was conducted where three contouring tasks were performed by eight physicians respectively. Four types of navigation interactions and five types of interaction sequence patterns were identified by analyzing the gathered interaction log data from those twenty-four cases. Further in-depth study on each of the navigation interactions and interaction sequence patterns in relation to the contextualized sensemaking model revealed five main areas for design improvements to increase sensemaking support. Outcomes of the case study indicate that the proposed two-step approach was beneficial for gaining a deeper understanding of the sensemaking process during the task, as well as for identifying design requirements for better sensemaking support.  相似文献   
39.
Benign prostatic hyperplasia (BPH) is the most common disease in elderly men. BPH symptoms include frequent urination, urgent tenesmus and urination at night, a weak and interrupted urine flow and a sense of incomplete emptying of the bladder. Alpha- 1 adrenergic receptor antagonists and 5 α-reductase inhibitors form the most important groups of medications employed in BPH. Appropriately managed BPH patients shall be subject to counselling on interactions between agents belonging to these groups, and on particular components of the food they have.The present review has been aimed at assessing potential effects of consumed food, alcohol and fruit juices on the pharmacokinetics and pharmacodynamics of medications for benign prostatic hyperplasia.The authors reviewed the English PubMed database covering the years 1991–2015. Additionally, a digital version of Stockley Drugs Interaction and other electronic databases such as drugs.com and Medscape were also researched; characterisation charts for particular medical products were also analyzed.Pharmacokinetics of extended-release forms of alfuzosin, doxazosin, tamsulosin and silodosin is well known to be food-sensitive. Alfuzosin, tamsulosin and silodosin due to their likely interaction with grapefruit juice and citrus fruits, may intensify adverse effects of the drugs. Alpha-1 adrenergic receptor antagonists are known to interact with alcohol, leading to orthostatic hypotension. For 5 alpha-reductase inhibitors, such as finasteride, or dutasteride, the pharmacokinetic effect due to consumed food is of no clinical importance and thus they may be taken regardless of meals.As in general grapefruit juice and alcohol tend to significantly affect the efficacy and safety of the applied drug therapy, it is highly advisable to be knowledgeable on the subject in order to educate patients.  相似文献   
40.
蔡练功  聂军 《实用医学杂志》2008,24(17):3064-3066
目的:了解大学生人格与社会支持的交互作用对网络成瘾的影响。方法:采用包括网络成瘾诊断量表(YIAS)、艾森克个性问卷简式量表(EPQ-RSC)、领悟社会支持量表(PSSS)以及个人网络使用情况调查的问卷对某医科大学950名本科生进行测查。结果:大学生的人格特质与领悟社会支持水平对网络成瘾的影响存在主效应的同时还存在联合作用效应(P<0.05)。结论:内向人格倾向的人,其领悟社会支持的水平越低,患网络成瘾的危险性越大。应当对这部分人群重点干预,以达到防治网络成瘾的目的。  相似文献   
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