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71.
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73.
Benjamin Sohmer MD Christopher Hudson MD Juliet Atherstone MD A. Stephane Lambert MD Michel Labrosse PhD Munir Boodhwani MD 《Journal canadien d'anesthésie》2013,60(1):24-31
Background
As aortic valve (AV) repairs become more sophisticated, surgeons need increasingly detailed information about the structure and function of this valve. Unlike two-dimensional transesophageal echocardiography (2D-TEE), using three-dimensional (3D)-TEE makes it possible to image the entire AV. We hypothesized that measuring coaptation surface area (CoapSA) would be feasible and reproducible, and CoapSA would decrease in patients with aortic insufficiency.Methods
We developed a new technique to calculate the AV-CoapSA using 3D-TEE. We measured the coaptation surfaces between the right coronary cusp/left coronary cusp, right coronary cusp/non-coronary cusp, and left coronary cusp/non-coronary cusp in ten normal AVs and ten AVs with moderate-severe aortic insufficiency (AI). Since computer models have previously shown that CoapSA is trapezoidal, we used the formula: trapezoid area = length × (medial coaptation height + lateral coaptation height)/2. The total CoapSA was calculated by adding all three areas. To adjust for valve size, we indexed the value to the diameter of the ventricular aortic junction (VAJ). Measurements were performed by two observers.Results
The intra-observer correlation was 0.84 for one observer (P < 0.0001) and 0.93 for the other (P < 0.0001). The inter-observer correlation was 0.87 (P < 0.0001). In normal valves, the CoapSA [mean total (standard deviation)] was significantly greater than in the insufficient valves [1.61 (0.31) cm2 vs 1.03 (0.22) cm2, respectively; P < 0.001]. After indexing for the VAJ diameter, the total CoapSA remained significantly greater in normal valves than in insufficient valves.Conclusion
In this proof of concept study, we present a new and innovative technique to measure AV-CoapSA using 3D-TEE. It is reproducible and shows decreased CoapSA in patients with AI. Coaptation surface area may provide insight into mechanisms of AI and may have predictive value following AV repair. 相似文献74.
Leif Johannsen Karen Z.H. Li Magdalena Chechlacz Attia Bibi Zoe Kourtzi Alan M. Wing 《Neuropsychologia》2013
Background
Limited information processing capacity in the brain necessitates task prioritisation and subsequent adaptive behavioural strategies for the dual-task coordination of locomotion with severe concurrent cognitive loading. Commonly observed strategies include prioritisation of gait at the cost of reduced performance in the cognitive task. Alternatively alterations of gait parameters such as gait velocity have been reported presumably to free processing capacity for the benefit of performance in the cognitive task. The aim of this study was to describe the neuroanatomical correlates of adaptive behavioural strategies in cognitive-motor dual-tasking when the competition for information processing capacity is severe and may exceed individuals’ capacity limitations.Methods
During an fMRI experiment, 12 young adults performed slow continuous, auditorily paced bilateral anti-phase ankle dorsi-plantarflexion movements as an element of normal gait at .5 Hz in single and dual task modes. The secondary task involved a visual, alphabetic N-back task with presentation rate jittered around .7 Hz. The N-back task, which randomly occurred in 0-back or 2-back form, was modified into a silent counting task to avoid confounding motor responses at the cost of slightly increasing the task′s general coordinative complexity. Participants’ ankle movements were recorded using an optoelectronic motion capture system to derive kinematic parameters representing the stability of the movement timing and synchronization. Participants were instructed to perform both tasks as accurately as possible.Results
Increased processing complexity in the dual-task 2-back condition led to significant changes in movement parameters such as the average inter-response interval, the coefficient of variation of absolute asynchrony and the standard deviation of peak angular velocity. A regions-of-interest analysis indicated correlations between these parameters and local activations within the left inferior frontal gyrus (IFG) such that lower IFG activations coincided with performance decrements.Conclusions
Dual-task interference effects show that the production of periodically timed ankle movements, taken as modelling elements of the normal gait cycle, draws on higher-level cognitive resources involved in working memory. The interference effect predominantly concerns the timing accuracy of the ankle movements. Reduced activations within regions of the left IFG, and in some respect also within the superior parietal lobule, were identified as one factor affecting the timing of periodic ankle movements resulting in involuntary ‘hastening’ during severe dual-task working memory load. This ‘hastening’ phenomenon may be an expression of re-automated locomotor control when higher-order cognitive processing capacity can no longer be allocated to the movements due to the demands of the cognitive task. The results of our study also propose the left IFG as a target region to improve performance during dual-task walking by techniques for non-invasive brain stimulation. 相似文献75.
Nayla Hariz Souha Bawab Mia Atwi Lucy Tavitian Pia Zeinoun Munir Khani Boris Birmaher Ziad Nahas Fadi T. Maalouf 《Psychiatry research》2013
This study aimed at investigating the reliability and validity of the Arabic Screen for Child Anxiety Related Emotional Disorders (SCARED) as a first child and adolescent anxiety screening tool in the Arab World. The English parent (SCARED-P) and child (SCARED-C) versions were translated into Arabic and administered along with the Arabic Strengths and Difficulties Questionnaire (SDQ) to 77 parents and 67 children attending a Psychiatry clinic. DSM-IV-TR diagnoses were made by a psychiatrist without knowledge of the scale scores. Internal consistency was confirmed by Cronbach's α=0.92 for SCARED-P and 0.91 for SCARED-C. Their subscales had internal consistencies between 0.65 and 0.89. Parent–child agreement was r=0.67, p<0.001. SCARED-P demonstrated good discriminant validity between participants with anxiety disorders and those with other psychiatric disorders (t(72)=3.13, p=0.003). For SCARED-C, this difference was significant when participants with depressive disorders were excluded (t(43)=2.58, p=0.01). Convergent validity was evident through a significant correlation between SCARED-P and the parent SDQ emotional subscale (r=0.70, p<0.001), and SCARED-C and the child SDQ emotional subscale (r=0.70, p<0.001). Divergent validity with the SDQ hyperactivity subscale was observed as no significant correlation was found. Overall, the Arabic SCARED demonstrated satisfactory psychometric properties in a clinical sample in Lebanon. 相似文献
76.
Muhammad Akram Muhammad Riaz Naveed Munir Akhtar Rasul Muhammad Daniyal Syed Muhammad Ali Shah Mohammad Ali Shariati Ghazala Shaheen Naheed Akhtar Farzana Parveen Naheed Akhter Aymen Owais Ghauri Abdul Wadood Chishti Muhammad Usman Sarwar Fahad Said Khan 《Clinical and experimental pharmacology & physiology》2020,47(7):1107-1119
The advent of antibiotics revolutionized medical care resulting in significantly reduced mortality and morbidity caused by infectious diseases. However, excessive use of antibiotics has led to the development of antibiotic resistance and indeed, the incidence of multidrug-resistant pathogens is considered as a major disadvantage in medication strategy, which has led the scholar's attention towards innovative antibiotic sources in recent years. Medicinal plants contain a variety of secondary metabolites with a wide range of therapeutic potential against the resistant microbes. Therefore, the aim of this review is to explore the antibacterial potential of traditional herbal medicine against bacterial infections. More than 200 published research articles reporting the therapeutic potential of medicinal plants against drug-resistant microbial infections were searched using different databases such as Google Scholar, Science Direct, PubMed and the Directory of Open Access Journals (DOAJ), etc., with various keywords like medicinal plants having antibacterial activities, antimicrobial potentials, phytotherapy of bacterial infection, etc. Articles were selected related to the efficacious herbs easily available to local populations addressing common pathogens. Various plants such as Artocarpus communis, Rheum emodi, Gentiana lutea L., Cassia fistula L., Rosemarinus officinalis, Argemone maxicana L, Hydrastis canadensis, Citrus aurantifolia, Cymbopogon citrates, Carica papaya, Euphorbia hirta, etc, were found to have significant antibacterial activities. Although herbal preparations have promising potential in the treatment of multidrug-resistant bacterial infection, still more research is required to isolate phytoconstituents, their mechanism of action as well as to find their impacts on the human body. 相似文献
77.
Association Between Combined Presence of Hepatitis C Virus and Polymorphisms in Different Genes With Toxicities of Methotrexate and 6‐Mercaptopurine in Children With Acute Lymphoblastic Leukemia
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78.
Ahmad Munir Abu‐Helalah MD MPH PhD Ahmad Hussam Alshraideh PhD Mo'tasem Al‐Hanaqtah MD Moh'd Da'na MD Asim Al‐Omari MD Rasmi Mubaidin MD 《The breast journal》2016,22(2):213-217
Breast cancer is the most common cancer, and one of the leading causes of death for females in Jordan and many countries in the world. Studies have shown that delay in symptoms presentation, diagnosis or treatment would result in poor prognosis. There has been no published study from Jordan on delays in patient presentation, delays in diagnosis, or delays in treatment. Therefore, we conducted this study to assess these important quality indicators aiming to improve prognosis for breast cancer patients in Jordan. This project was a cross‐sectional study on female breast cancer patients in Jordan. The total number of participants was 327. The proportion of patients with presentation delay, diagnosis delay, and treatment delay was 32.2%, 49.1%, or 32.4%, respectively. The main reported reasons for delay in presentation were ignorance of the nature of the problem (65.6%), limited/lack of knowledge that symptoms were suggestive of cancer diagnosis (16.7%), and misdiagnosis (16.7%). Predictors of delay and mean time for presentation, diagnosis, and treatment were identified. Our results reveal that breast cancer patients in Jordan are experiencing delays in presentation, diagnosis, and treatment. This could justify the advanced stages at diagnosis and poor outcomes for breast cancer patients in Jordan. We recommend revising the current early detection and down‐staging programs in Jordan. 相似文献
79.
Aims
This paper investigates the distributional implications for eight population groups of using six different instruments to measure wellbeing and to prioritise access to health services. Specifically, it examines the importance of different physical and psycho-social problems for the scores obtained using each instrument and whether scores differ because of differences in the concept measured by the instrument or because of the instrument’s construction.Methods
Patients with seven chronic conditions and a sample of the ‘healthy’ public were administered six instruments: two utility instruments; two self-rating scales; a subjective wellbeing instrument and the ICECAP measure of capability. Scores were regressed upon the subscales of the SF-36 and the AQoL-8D. Each instrument’s ‘problem mix’ was measured by the numerical importance of the subscales for the instrument’s score and compared with the problem mix of patients constructed from all of the instruments.Results
The apparent importance of different problems varied significantly with the instrument used to assess welfare but not with the chronic conditions. The correspondence between an instrument’s problem mix and the patients’ problem mix was highly variable.Conclusion
Different instruments give prominence to different physical and psycho-social problems and consequently favour different groups of patients. Budgetary decisions which appear to be based on efficiency criteria such as the cost per quality-adjusted life year (QALY) conceal distributive effects attributable to the instrument used in the analysis. The effects are additional to the ethical questions considered in making an equity–efficiency trade-off as they arise from the measurement of efficiency.80.
Community-dwelling stroke survivors: function is not the whole story with quality of life 总被引:1,自引:0,他引:1
White JH Alston MK Marquez JL Sweetapple AL Pollack MR Attia J Levi CR Sturm J Whyte S 《Archives of physical medicine and rehabilitation》2007,88(9):1140-1146
OBJECTIVE: To compare function and quality of life in community-dwelling stroke survivors at 1, 3, and 5 years after stroke. DESIGN: A community-based, cross-sectional study of 3 retrospective cohorts. SETTING: Community-dwelling stroke survivors in Australia. PARTICIPANTS: The 3 cohorts comprised 30 participants each at 1, 3, and 5 years poststroke discharge from a tertiary referral hospital. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Stroke severity, comorbidity, medications used, and demographic information were recorded. Poststroke function was assessed using the Modified Rankin Scale, Mini-Mental State Examination, Stroke Impact Scale, and Multidimensional Scale of Perceived Social Support. RESULTS: This cross-sectional study provides insights into trends in stroke survivors over time. A high proportion of stroke survivors use community services, even those who are independent with activities of daily living. Although there was little attrition in medication use over time except for warfarin, this was from a baseline of suboptimal compliance and adherence with stroke preventive therapies. Stroke survivors report high levels of perceived social support; however, emotional well-being was low overall. The data suggest that those who are independent at 1 year tend to remain independent, although this was an extrapolation from serial cross-sections and needs to be explored in a longitudinal study. CONCLUSIONS: Stroke survivors' function does not change significantly over time. A high proportion of survivors require community services. The development of needs-related effective long-term service delivery models is required. 相似文献