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71.
Sears SF Serber ER Alvarez LG Schwartzman DS Hoyt RH Ujhelyi MR 《Pacing and clinical electrophysiology : PACE》2005,28(8):801-807
BACKGROUND: Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with a variety of symptoms such as dizziness, palpitations, shortness of breath, and other signs of heart failure, which in turn impact quality of life (QOL). Implantable cardioverter defibrillators with atrial therapies (ICDs-ATs) have been shown to reduce AF symptoms and improve QOL in select AF samples. METHOD: This study examined the strength of relationships between objective (device-detected AF events) versus subjective (emotional symptoms) data and AF symptoms (number) reported as part of the Patient Atrial Shock Survey of Acceptance and Tolerance Study (N = 96, 72% men, M age = 65, SD = 12). Depression and anxiety were assessed via the Center for Epidemiological Studies--Depression Scale and the-State Trait Anxiety Inventory. AF disease burden was measured via a number of device-detected AF episodes and the Atrial Tachyarrhythmia Symptom Severity Scale. RESULTS: Hierarchical multiple regression analysis indicated that negative emotions accounted for a significant 13.2% of unique variance in AF symptom score (F change (1, 54) = 9.625, P = 0.003). On the other hand, the number of device-detected AF episodes accounted for non-significant 8.2% of unique variance in the AF symptom score (P = 0.167). The full model explained 25.7% of the variance in AF symptom score (F(6, 54) = 3.110, P = 0.011). Specifically, greater number of treated AF episodes (beta= 0.251, P = 0.043) and higher levels of negative emotions (beta= 0.369, P = 0.003) predicted greater number of reported AF symptoms. CONCLUSION: Therefore, psychological distress may be a significant confounding factor affecting patient's report of AF symptoms rather than the actual experience of recurrent AF episodes. 相似文献
72.
In recent years, the ophthalmic examination of infants has been of increasing interest to both clinicians and vision researchers. Clinicians have documented a greater risk of retinopathy, strabismus and amblyopia in premature infants, especially those of low birthweight. In addition to the external and retinal examination of the infant eye, a number of clinical tests can help the ophthalmologist to detect visual dysfunction through the evaluation of pupillary responses and ocular motility. Recently, the development of objective techniques (optokinetic nystagmus, forced choice preferential looking, and visually evoked potentials) have not only aided in the detection of ophthalmic disorders in infants; they have contributed to useful definitions of “normal” vision at various ages and to the understanding of factors that influence the pre- and post-gestational development of visual function. 相似文献
73.
A Hoyt M A Thompson F J Moore C R Smith 《The American review of respiratory disease》1967,95(5):806-819
74.
The ability to image and quantitate fluorescently labeled markers in vivo has generally been limited by autofluorescence of the tissue. Skin, in particular, has a strong autofluorescence signal, particularly when excited in the blue or green wavelengths. Fluorescence labels with emission wavelengths in the near-infrared are more amenable to deep-tissue imaging, because both scattering and autofluorescence are reduced as wavelengths are increased, but even in these spectral regions, autofluorescence can still limit sensitivity. Multispectral imaging (MSI), however, can remove the signal degradation caused by autofluorescence while adding enhanced multiplexing capabilities. While the availability of spectral "libraries" makes multispectral analysis routine for well-characterized samples, new software tools have been developed that greatly simplify the application of MSI to novel specimens. 相似文献
75.
Recent research on the social support networks of homeless and runaway youth suggest the social networks of runaway youth are made up largely of transient deviant peer relationships. This paper examined social network characteristics of 428 homeless and runaway adolescents from small-to moderate-sized cities in four Midwestern states. We investigated size, homogeneity, and correlates of the composition of the instrumental and emotional support networks as reported by the adolescents. Results showed the networks are considerably heterogeneous, comprised of relationships from home and the street as well as family and non-related adults. Further, the composition of these networks is related to adolescent characteristics and experiences including sexual identity, abuse history, and street experience. 相似文献
76.
77.
Abdominal wall hernia repair: a long-term comparison of Sepramesh and Dualmesh in a rabbit hernia model 总被引:7,自引:0,他引:7
Surgeons are faced with a wide variety of mesh products, which they can use to perform tension-free abdominal wall hernia repair. The purpose of this study is to compare Sepramesh (SM) and Dualmesh (DM) in terms of strength of tissue incorporation, mesh shrinkage, and adhesiogenesis. We conducted a prospective, randomized trial using 24 New Zealand White rabbits. Each animal underwent creation of a standardized ventral hernia defect and was randomized to receive either SM or DM repair. There were 12 animals in each study arm. Five months postoperatively, the animals were sacrificed and the hernia repairs were analyzed. Specimens were evaluated for strength of incorporation (SOI), mesh shrinkage, as well as the type and amount of adhesions. SOI for DM was not statistically different from SM (37.2N vs 40.8N). DM underwent significantly more shrinkage than did SM (50.8% vs 32.6%, P < 0.0001). Adhesions were predominantly omental in nature. DM demonstrated a greater amount of adhesed area as a percentage of the mesh (30.7% vs 25.2%), but fewer adhesions in terms of absolute area involved (636 mm2 vs 717 mm2). This difference was not statistically significant. Previous studies, terminated at 30 days, demonstrated an increased SOI for SM as compared to DM. This study shows that SOI for DM continues to increase over time such that it is equivalent to DM at 5 months. Though there is increased mesh shrinkage for DM, adhesions to the two materials are equivalent. 相似文献
78.
Creer AR Ricard MD Conlee RK Hoyt GL Parcell AC 《International journal of sports medicine》2004,25(2):92-98
The purpose of this study was to investigate the effects of short-term, high-intensity sprint training on the root mean squared (RMS) and median frequency (MF) derived from surface electromyography (EMG), as well as peak power, mean power, total work, and plasma lactate levels in trained cyclists when performed concurrently with endurance training. Seventeen trained cyclists were randomly assigned to a sprint training (S) group (n = 10, age 25 +/- 2.0 y) or a control (C) group (n = 7, age 25 +/- 0.5 y). Sprint training was performed bi-weekly for four weeks, comprising a total of 28 min over the training period. EMG measurements were taken before and after training during a series of four 30-s sprints separated by four minutes of active recovery. Plasma lactate, peak power, mean power, and total work were measured during each sprint bout. Following sprint training a significant increase occurred in the RMS of the vastus lateralis with a decrease in MF of the same muscle. Values for the vastus medialis did not change. Pre training exercising plasma lactate values were higher (p < 0.05) in C compared to S, but did not change with training. Exercising plasma lactate values increased (p < 0.05) from pre to post training in S, but were not different from C post training. Total work output increased from pre to post in S (p = 0.06). Peak power, mean power, and V.O (2)max increased (p < 0.05) pre to post training in S and C, indicating C was not a true control. In conclusion, these data suggest that four weeks of high-intensity sprint training combined with endurance training in a trained cycling population increased motor unit activation, exercising plasma lactate levels, and total work output with a relatively low volume of sprint exercise compared to endurance training alone. 相似文献
79.
The impact of major trauma: quality-of-life outcomes are worse in women than in men, independent of mechanism and injury severity 总被引:2,自引:0,他引:2
BACKGROUND: The importance of gender differences in quality of life and psychologic morbidity after major trauma is a newly recognized focus of trauma outcomes research. The Trauma Recovery Project is a large, prospective, epidemiologic study designed to examine multiple outcomes after major trauma, including quality of life (QoL), and psychologic sequelae such as depression and early symptoms of acute stress reaction (SASR). The specific objectives of the present report are to examine gender differences in QoL outcomes and the early incidence of combined depression and SASR after injury, controlling for injury severity, specific body area injured, and mechanism. METHODS: Between December 1, 1993, and September 1, 1996, 1,048 eligible trauma patients triaged to four participating trauma center hospitals in the San Diego Regionalized Trauma System were enrolled in the study. The enrollment criteria for the study included age 18 years and older, admission Glasgow Coma Scale score of 12 or greater, and length of stay greater than 24 hours. QoL outcome after trauma was measured after injury using the Quality of Well-being scale, a sensitive index to the well end of the functioning continuum (range, 0 = death to 1.000 = optimum functioning). Depression was assessed using the Center for Epidemiologic Studies scale. SASR was assessed using the Impact of Events scale. Patient outcomes were assessed at discharge and at 6, 12, and 18 months after discharge. RESULTS: Women (n = 313) were significantly more likely to have poor QoL outcomes at follow-up than men (n = 735) (women vs. men: 12-month follow-up odds ratio [OR] = 2.2, p < 0.001; 18-month follow-up OR = 2.0, p < 0.001). Quality of Well-being scores at each of the 6-, 12-, and 18-month follow-up time points were markedly and significantly lower in women compared with men, independent of injury severity, serious and moderate injury status, lower extremity injury, intentional or unintentional injury type, and blunt or penetrating injury. Women were also significantly more likely to develop early combined depression and SASR at discharge (OR = 1.7, p < 0.01) and to have continuous depression throughout the 18-month follow-up period (OR = 2.3, p < 0.001). CONCLUSION: These analyses provide further important and more detailed evidence that women are at risk of worse QoL outcomes and early psychologic morbidity after major trauma than men, independent of mechanism and injury severity. A better understanding of the impact of major trauma in men and women will be an important component of efforts to improve trauma care and long-term outcome in mature trauma systems. 相似文献
80.
The epidemiology of serious and fatal injury in San Diego County over an 11-year period 总被引:2,自引:0,他引:2
Potenza BM Hoyt DB Coimbra R Fortlage D Holbrook T Hollingsworth-Fridlund P;Trauma Research Education Foundation 《The Journal of trauma》2004,56(1):68-75
BACKGROUND: Analysis of the mechanism and severity of injury over time may permit a more focused planning of acute care and trauma prevention programs. METHODS: A retrospective, population-based study examining severe traumatic injury in a single county was undertaken. Three overlapping data sets were used to form a composite injury data set. RESULTS: There were 55,664 patients included in the study. A total of 40,897 (73.5%) patients survived and 14,767 (26.5%) died. Of those patients who died, 8,910 (60.3%) died in the field and were not transported to a trauma center. There was an increase in the mean age of all trauma victims (3 years) and an increase of 5 years in fatally injured patients. The mean Injury Severity Score decreased from 14.7 to 11.6 (p < 0.01); however, Injury Severity Score for fatal patients remained constant (39.7). The overall injury rate remained unchanged (195 per 10(5)), whereas the fatal injury rate decreased by 22% (45.9 per 10(5)) over the 11-year study period. The leading cause of injury was motor vehicle crash, followed by assault. The leading cause of fatal injury was suicide, followed by homicide. CONCLUSION: A combination of three independent injury data sources generated a composite data set of serious and fatal injury. This regional injury analysis was the most comprehensive overview of injury in our region. Important observations included the following: there has been no change in the overall incidence of severe injury within our county; the incidence of fatal traumatic injury has significantly decreased; the leading causes of nonfatal injury do not correlate with the rank order of fatal injury; intentional injury was the leading cause of injury deaths; and scene fatalities represent a poorly studied group of patients who may benefit from primary prevention and injury control research. 相似文献