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21.
Two-dimensional speckle-tracking strain imaging (speckle strain imaging) is useful for evaluating left ventricular myocardial function in patients with ischemic heart disease and cardiomyopathy, including hypertrophic and dilated phenotypes. The usefulness of speckle strain imaging in patients with pheochromocytoma who are undergoing adrenal surgery has been described, but we found no reports of the use of this method to evaluate ventricular dysfunction longitudinally in children. Herein, we describe the case of a 10-year-old girl with a paraganglioma, acute junctional tachycardia, and myocardial dysfunction. After control of the tachycardia and partial resection of the tumor, speckle strain imaging enabled clinical management that led to substantial improvement in the patient's initially diffuse myocardial dysfunction. Because conventional echocardiographic methods alone may be inadequate to guide the management of pediatric patients with partially resected neuroendocrine tumors, we recommend speckle strain imaging as an additional noninvasive option for treatment guidance and monitoring of cardiac tissue response.  相似文献   
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Two multiple probe designs across three and four participants evaluated the effects of video modeling to teach a matching response (sorting mail) to seven adolescents with autism. Participants were instructed on one set of responses (five mail pieces) using video modeling, while concurrently monitoring two other sets for generalization effects. Results indicated that three participants learned their target set and generalized to the untrained sets, and two participants required an error correction procedure to achieve or approach mastery on their target set. Two participants did not acquire target sets with video based instruction. Data on setting generalization and maintenance are also provided for the participants who reached mastery. Participant variables that may relate to responding, limitations to the study, and directions for future research on video based instruction are discussed.  相似文献   
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The factors which contribute to an exaggerated blood pressure response (EBPR) during the exercise treadmill test (ETT) are not wholly understood. The association between the insertion/deletion polymorphisms of the angiotensin-converting enzyme (ACE) and M235T of the angiotensinogen with EBPR during ETT still remains unstudied. To identify and compare the risk factors for hypertension between normotensive subjects with EBPR and those who exhibit a normal curve of blood pressure (BP) during ETT. In a series of EBPR cases from a historical cohort of normotensive individuals, a univariate analysis was performed to estimate the association of the studied factors with BP behavior during ETT. Additionally, logistic multivariate regression was conducted to analyze the joint effects of the variables. P-values above 0.05 were considered statistically significant. From a total of 10,027 analyzed examinations, only 219 met the criteria employed to define EBPR, which resulted in a prevalence of 12.6%. For the systolic component of the BP, hyperreactive subjects displayed a mean age and body mass index (BMI) significantly higher than the others (P=0.002 and <0.001, respectively). No association was observed between the polymorphisms cited above and EBPR. An analysis of the joint effect of variables has indicated that only age (P< 0.001) and BMI (P=0.001) were specifically associated with systolic BP during exercise. Age and BMI were the only factors that independently influenced EBPR during ETT.  相似文献   
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It is widely accepted that air pollution can exacerbate asthma in those who already have the condition. What is less clear is whether air pollution can contribute to the initiation of new cases of asthma. Mechanistic evidence from toxicological studies, together with recent information on genes that predispose towards the development of asthma, suggests that this is biologically plausible, particularly in the light of the current understanding of asthma as a complex disease with a variety of phenotypes. The epidemiological evidence for associations between ambient levels of air pollutants and asthma prevalence at a whole community level is unconvincing; meta-analysis confirms a lack of association. In contrast, a meta-analysis of cohort studies found an association between asthma incidence and within-community variations in air pollution (largely traffic dominated). Similarly, a systematic review suggests an association of asthma prevalence with exposure to traffic, although only in those living very close to heavily trafficked roads carrying a lot of trucks. Based on this evidence, the U.K.'s Committee on the Medical Effects of Air Pollutants recently concluded that, overall, the evidence is consistent with the possibility that outdoor air pollution might play a role in causing asthma in susceptible individuals living very close to busy roads carrying a lot of truck traffic. Nonetheless, the effect on public health is unlikely to be large: air pollutants are likely to make only a small contribution, compared with other factors, in the development of asthma, and in only a small proportion of the population.  相似文献   
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Acute myocardial infarction evokes a characteristic neurohumoral response: Catecholamine release is increased, plasma contents of free fatty acids and glucose are elevated and glucose tolerance is diminished. To what degree the myocardium participates in this stress response was evaluated by sampling coronary sinus and arterial blood in 50 patients with acute transmural infarction. Studies were initiated an average of 8 hours after the clinical onset of infarction and were continued for up to 60 hours. A total of 173 separate metabolic studies were analyzed. Forty-one percent exhibited a pattern of predominant myocardial free fatty acid uptake (mean extraction ratio 24 percent) in the presence of elevated plasma free fatty acid and glucose contents (respective means 1,181 μmol/liter and 210 mg/100 ml). Myocardial extraction ratios for glucose, lactate and pyruvate were low (respective means 1.1, 4 and 11 percent). Twenty-one percent of the studies revealed normal myocardial metabolism and 18 percent showed enhanced carbohydrate uptake, as evidenced by increased myocardial extractions of lactate and pyruvate (respective means 42 percent) and of glucose (mean 5 percent). Plasma contents of glucose and free fatty acids were lower than in the predominant free fatty acid group (respective means 156 mg/100 ml and 743 μmol/liter). The remaining 20 percent of studies showed high plasma substrate contents and low myocardial substrate uptake suggesting metabolic breakdown. The free fatty acid metabolic pattern was observed in more than 50 percent of the studies performed at the time of or close to the occurrence of important clinical complications. Propranolol, 0.1 mg/kg intravenously, shifted myocardial substrate utilization from free fatty acids toward carbohydrates. The myocardial respiratory quotient increased from an average of 0.79 to 0.88 (P < 0.01).The study demonstrates that the metabolic patterns of the myocardium are influenced by the systemic response to stress. Beta adrenergic blockade changed substrate utilization of the myocardium, supporting the hypothesis that adrenergic activation plays an important role in these metabolic responses.  相似文献   
27.
Long term treatment of severe asthma with subcutaneous terbutaline   总被引:6,自引:0,他引:6  
We have investigated the use of subcutaneous terbutaline in 17 patients with brittle asthma and five patients with chronic severe asthma. Twelve of the 17 patients with brittle asthma improved both subjectively and objectively (mean lowest daily PEF rising from 142 litres/min to 297 litres/min), with reduction in oral steroid dose, nebulized beta-agonist dose and number of hospital admissions. Both continuous infusion and 6-hourly divided dose regimens were equally effective. Only one of the five with chronic severe asthma showed any lasting response. Eighteen patients have continued to use subcutaneous terbutaline over long periods (2-40 months). Overall 11 patients suffered side-effects of usually minor degree, although one patient had to withdraw because of the development of painful subcutaneous nodules. We conclude that subcutaneous terbutaline delivered by infusion or by intermittent injections is a useful addition to the therapy of some patients with brittle asthma.  相似文献   
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Background Potentially inappropriate medications (PIMs) should be avoided by the elderly because they possess a significant high risk for this population when a safer alternative is available. Therefore, the identification of prevalence and factors associated with PIMs should be considered as they provide valuable information that can be used to develop strategies to ensure patients’ safety. Objective To identify the prevalence and the clinical and socioeconomic–demographic factors that may be associated with PIMs use in the elderly, according to Beers criteria 2003 and its updated version 2012. And, as a secondary objective, a comparison between both criteria was performed. Setting Pharmacy of the Basic Health District Unit of the western district of Ribeirão Preto. Methods This cross-sectional observational study was conducted with the elderly, assisted by the Brazilian public health system. Data from patients were collected through a structured interview form. Beers criteria 2003 and 2012 were used to classify PIMs. The association between PIMs used and independent variables were analyzed by odds ratios. The differences between PIMs use according to Beers criteria 2003 and 2012 were analyzed by McNemar’s test and the agreement by kappa coefficient. Main outcome measure Prevalence and factors associated with PIMs use in Brazilian elderly outpatients. Results One thousand elderly patients were interviewed. High prevalence of PIMs use was observed, 48.0 and 59.2 % according to Beers criteria 2003 and 2012, respectively. The factors associated with PIMs use, common for both criteria, are female gender, self-medication, use of over the counter drugs, complaints related to adverse drug event, psychotropic medication, polypharmacy and some categories of drugs. PIMs use is different between Beers criteria 2003 and 2012 (McNemar’s test, p < 0.01), although a substantial agreement between these classifications was observed (kappa coefficient 0.635, 95% confidence intervals (0.588, 0.681). Conclusions Our study showed a high prevalence of PIMs use, which is associated with various clinical and social–demographic factors. When comparing both criteria through McNemar’s test, PIMs use was considered different. The differences may have occurred because medications with high prevalence of use in Brazil were included in Beers criteria 2012 .  相似文献   
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