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11.
Heavy metal accumulation of lead (Pb), chromium (Cr), and cadmium (Cd) in the muscle of the catfish Eremophilus mutisii was studied in 47 specimens, captured by anglers in the Bogotá River at two sampling sites (Chocontá and Suesca) during May–October 2005. Water samples were processed for physicochemical and metal analyses. Metal accumulation in muscle (wet weight) of specimens at Chocontá and Suesca showed high levels of Pb (3.4 and 3.1 ppm, respectively), Cr (1.8 and 2.1 ppm, respectively), and Cd (0.35 and 0.48, respectively). Metal levels in waters (ppm) indicated that average Pb (0.028 Chocontá, 0.029 Suesca), Fe (0.462 Chocontá, 1.1 Suesca), and Cr (0.113 Chocontá) were above the maximum levels (MCLs) allowed in drinking waters. No extreme average values were found for pH, nitrites, alkalinity, and hardness in the waters. This study showed the importance of benthic and nonmigratory species like the capitán to evaluate the effects of heavy metals pollution. Further public health implications could be derived in the region where this investigation took place due to consumption of capitán by people in the area.  相似文献   
12.
Seventy-eight children, referred to a diet clinic because of hyperactive behaviour, were placed on a 'few foods' elimination diet. Fifty nine improved in behaviour during this open trial. For 19 of these children it was possible to disguise foods or additives, or both, that reliably provoked behavioural problems by mixing them with other tolerated foods and to test their effect in a placebo controlled double blind challenge protocol. The results of a crossover trial on these 19 children showed a significant effect for the provoking foods to worsen ratings of behaviour and to impair psychological test performance. This study shows that observations of change in behaviour associated with diet made by parents and other people with a role in the child's care can be reproduced using double blind methodology and objective assessments. Clinicians should give weight to the accounts of parents and consider this treatment in selected children with a suggestive medical history.  相似文献   
13.
Objective : To review Australian policies on active transport, defined as walking and cycling for utilitarian purposes. To estimate the potential health impact of achieving four active transport policy scenarios. Methods : A policy review was undertaken, using key words to search government websites. Potential health benefits were quantified using a cohort simulation Markov model to estimate obesity and transport injury‐related health effects of an increase in active transport. Health adjusted life years (HALYs) gained and healthcare cost savings from diseases averted were estimated. Budget thresholds to achieve cost‐effectiveness were estimated for each scenario. Results : There is broad recognition of the health‐related benefits of active transport from all levels of Australian government. Modelling results suggest significant health‐related benefits of achieving increased prevalence of active transport. Total HALYs saved assuming a one‐year effect ranged from 565 (95%UI 173–985) to 12,105 (95%UI 4,970–19,707), with total healthcare costs averted ranging from $6.6M (95%UI $1.9M‐11.3M) to $141.2M (95%UI $53.8M–227.8M). Conclusion : Effective interventions that improve rates of active transport may result in substantial healthcare‐related cost savings through a decrease in conditions related to obesity. Implications for public health : Significant potential exists for effective and cost‐effective interventions that result in more walking and cycling.  相似文献   
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15.
The safety factor (SF) for neuromuscular transmission varies across limb muscles of different fiber-type composition. Using intracellular recordings in rat diaphragm fibers, we found that SF varies across muscle fiber types (even within a single muscle), being larger for type IIx or IIb fibers than for type I or IIa fibers. Fiber-type differences in activation history or mechanical load may contribute to differences in SF and are important determinants of neuromuscular plasticity.  相似文献   
16.
Congenital ventricular aneurysm is an infrequently occurring disease entity that usually affects the left ventricle. Its etiopathology is unknown. Clinical presentation is variable, and the condition is potentially lethal in some cases. Various imaging techniques are useful in diagnosis and enable the condition to be differentiated from congenital left diverticulum. We present a patient with a calcified congenital ventricular aneurysm who presented with supraventricular and ventricular arrhythmias and who was treated by surgical resection.  相似文献   
17.
INTRODUCTION AND OBJECTIVES: Gated-SPECT simultaneously evaluates perfusion and ventricular function and could provide important prognostic information in ischemic cardiomyopathy. Our aim was to study the value of gated-SPECT performed before revascularization in a cardioischemic population to predict the outcome of revascularization. METHODS: One hundred and ten patients who had undergone percutaneous (n = 100) or surgical revascularization were included. Patients underwent sestamibi gated-SPECT before revascularization. After revascularization, they were followed-up for at least 12 months (mean 23.7 months, maximum 44 months). We recorded deaths and a combined clinical event of death, non-fatal infarction, and hospital re-admission for cardiac reasons. We analyzed the prognostic value of clinical, angiographic, and gated-SPECT variables. RESULTS: During follow-up, there were 14 deaths (6.4%/ year) and 36 cases of combined events (16.5%/year). Multivariate analysis showed that depressed gated-SPECT ejection fraction (threshold 0.30) was the only variable independently related to death (OR = 4.8; 95%CI, 1.6-14.6) and combined event (OR = 2.5; 95%CI, 1.2-4.8). Survival analysis showed that patients with ejection fraction < or = 0.30% had a significantly shorter period of time free of death (33 months [28-38] versus 42 months [40-44]; p = 0.002) and combined events (28 months [23-32] versus 36 months [33-39]; p = 0.007). CONCLUSIONS: Gated-SPECT, due to the information it provides about left ventricular function, predicts the prognosis of patients after coronary revascularization.  相似文献   
18.
Poncet’s disease (PD) is an entity described as a reactive arthritis due to tuberculous infection elsewhere from the joints. PD existence has been questioned; however, more cases have been reported over the years. Due to its rare nature, little is known about the clinical picture of this disease and no prospective studies had been made to address this issue. We performed a systematic review of the written literature on PD in different databases using the key words “Poncet’s disease,” “tuberculous rheumatism,” and “tuberculous reactive arthritis.” Out of 78 articles, 198 patients were included in the analysis, plus our patient. Several characteristic patterns were found. Also, a review of the pathogenesis and some hypotheses are made. PD is a well-defined entity, which should be taken as a reactive arthritis for future studies given the increase in TB incidence and prevalence around the world, especially in high-burden countries.  相似文献   
19.
Background and aimsPatients with stable coronary heart disease (CHD) and atherogenic dyslipidemia (AD) have a high-risk of recurrence and are those who derive most benefit from treatment with lipid-lowering agents. The aim of this study was to examine the prevalence of AD in patients with stable coronary heart disease and to investigate associated factors.MethodsCross-sectional study involving 7823 subjects admitted for a coronary event between 6 months and 10 years previously. AD was considered to be the concurrent presence of low HDL-cholesterol (<1.03 mmol/L [40 mg/dL] in males, <1.29 mmol/L [50 mg/dL] in females) and elevated triglycerides (≥1.7 mmol/L [150 mg/dL]).ResultsMean age was 65.3 (10.1) years, 73.6% were males and 80.3% were receiving treatment with statins. Low HDL-cholesterol was observed in 26.3% of the participants, 39.7% had elevated triglyceride concentration and 13.0% had AD. The percentage of AD in patients with criteria for metabolic syndrome was 30.9%. Factors associated directly and independently with the presence of AD in the multivariate analysis were female sex, history of coronary syndrome without ST elevation or coronary revascularization, presence of atrial fibrillation, body mass index, LDL-cholesterol, systolic blood pressure and blood glucose levels, while age and glomerular filtration rate were significantly and inversely associated with AD.ConclusionA significant proportion of patients with coronary disease could benefit from interventions aimed at increasing HDL-cholesterol and reducing triglycerides.  相似文献   
20.
Background: The role of preoperative gabapentin in postoperative pain management is not clear, particularly in patients receiving regional blockade. Patients undergoing thoracotomy benefit from epidural analgesia but still may experience significant postoperative pain. We examined the effect of preoperative gabapentin in thoracotomy patients. Methods: Adults undergoing elective thoracotomy were enrolled in this prospective, randomized, double‐blinded, placebo‐controlled study, and randomly assigned to receive 600 mg gabapentin or active placebo (12.5 mg diphenhydramine) orally within 2 hours preoperatively. Standardized management included thoracic epidural infusion, intravenous patient‐controlled opioid analgesia, acetaminophen and ketorolac. Pain scores, opioid use and side effects were recorded for 48 hours. Pain was also assessed at 3 months. Results: One hundred twenty patients (63 placebo and 57 gabapentin) were studied. Pain scores did not significantly differ at any time point (P = 0.53). Parenteral and oral opioid consumption was not significantly different between groups on postoperative day 1 or 2 (P > 0.05 in both cases). The frequency of side effects such as nausea and vomiting or respiratory depression was not significantly different between groups, but gabapentin was associated with decreased frequency of pruritus requiring nalbuphine (14% gabapentin vs. 43% control group, P < 0.001). The frequency of patients experiencing pain at 3 months post‐thoracotomy was also comparable between groups (70% gabapentin vs. 66% placebo group, P = 0.72). Conclusions: A single preoperative oral dose of gabapentin (600 mg) did not reduce pain scores or opioid consumption following elective thoracotomy, and did not confer any analgesic benefit in the setting of effective multimodal analgesia that included thoracic epidural infusion.  相似文献   
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