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Atypical atrial flutter has, hitherto, been relatively refractory totermination by rapid atrial pacing. High-frequency pacing (HFP) in theatrium, for termination of atrial flutter or atrial fibrillation (AF), andthe electrophysiologic effects related to it have not been examined. Weexamined the clinical efficacy, safety, and electrophysiologic mechanisms ofHFP using 50-Hz bursts at 10 mA applied at the high right atrium in patientswith atypical atrial flutter (group 1) or AF (group 2), using a prospectiverandomized study protocol. Four burst durations (500, 1000, 2000, and 4000ms) were applied at the high right atrium repetitively in random sequence in22 patients with spontaneous atrial flutter or AF. Local and distant rightand left atrial electrogram recordings were analyzed during and after HFP.HFP resulted in local and distant right and left atrial electrogramacceleration in 8 of 10 patients (80%) in group 1 but caused lessfrequent local atrial electrogram acceleration (6 of 12 patients) and nodistant atrial electrogram effects in group 2 (p < .05 versus group 1).The HFP protocol was effective in arrhythmia termination in 6 of 10patients in group 1 but in no patient in group 2 (p < .05 versus group1). Standard HFP protocol applied at the high right atrium can frequentlyalter atrial activation in both atria and can terminate atypical atrialflutter. Efficacy in AF is limited, probably due to limitedelectrophysiologic actions beyond the local pacing site.  相似文献   
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Beta-cell replacement is considered to be the most promising approach for treatment of type 1 diabetes. Its application on a large scale is hindered by a shortage of cells for transplantation. Activation of insulin expression, storage, and regulated secretion in stem/progenitor cells offers novel ways to overcome this shortage. We explored whether fetal human progenitor liver cells (FH) could be induced to differentiate into insulin-producing cells after expression of the pancreatic duodenal homeobox 1 (Pdx1) gene, which is a key regulator of pancreatic development and insulin expression in beta cells. FH cells possess a considerable replication capacity, and this was further extended by introduction of the gene for the catalytic subunit of human telomerase. Immortalized FH cells expressing Pdx1 activated multiple beta-cell genes, produced and stored considerable amounts of insulin, and released insulin in a regulated manner in response to glucose. When transplanted into hyperglycemic immunodeficient mice, the cells restored and maintained euglycemia for prolonged periods. Quantitation of human C-peptide in the mouse serum confirmed that the glycemia was normalized by the transplanted human cells. This approach offers the potential of a novel source of cells for transplantation into patients with type 1 diabetes.  相似文献   
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Purpose:To estimate prevalence of common ocular morbidities including color blindness among school-attending children of an urban foothill town of Uttarakhand State in Northern India.Methods:A cross-sectional study was conducted among school-going children of age group 6–16 years of standard I–XII. Schools were selected using population proportionate to the size sampling technique. Detailed ocular examination including color vision and unaided or aided visual acuity for various ocular morbidities was done. Data was entered into MS excel with statistical analysis using SPSS version 23 with significant P value <0.05.Results:In total, 13,492 students (mean age 10.9 ± 2.7 years) with almost equal male to female ratio were screened. Overall prevalence of ocular morbidity was 23.2%, with refractive error (18.5%) on top, followed by color blindness (2.2%). The later was observed more among males (3.0%) as compared to females (1.4%) with significantly higher odds, OR = 2.3 (1.7–2.9) (P < 0.001).Conclusion:Refractive error has been the most common ocular morbidity, followed by color blindness. Earliest detection can prevent permanent disability and disappointment among youngsters when rejected from entering certain professions due to color vision defect.  相似文献   
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Aims

Emergency admission to hospital is associated with an economic burden and mortality. Echocardiography is often the first‐line cardiovascular imaging investigation. Repeat testing is common; however, there are sparse data on the prevalence, appropriateness, or outcome of repeat testing.

Methods

We performed an electronic database search for patients with emergency admissions to our institution in February 2015. An electronic patient record review of inpatient echocardiograms was undertaken. Indications for echocardiography were classified as appropriate, may be appropriate, or rarely appropriate. One‐year follow‐up for repeat testing and mortality was investigated.

Results

A total of 409 of 2306 (17.7%) unplanned/emergency admissions underwent inpatient echocardiography. Abnormalities were identified in 165/409 (40.3%) of these patients; 154 of 409 (37.7%) had a repeat echocardiogram within the next year. Rarely appropriate indications for echocardiography occurred in 51 (33%) of repeat vs 53 (16%) of index echocardiograms, P < .0001. Repeat testing was associated with a change in findings in 17/154 (11%) patients overall. All of whom had an abnormal index echocardiogram and had an appropriate indication. There was no difference in mean survival time between patients who underwent repeat and those who only underwent a single index echocardiogram (310 days vs 327 days), P = .34.

Conclusion

Inpatient echocardiography in emergency hospital admissions identifies clinically important pathology. Repeated testing is common within 1 year of hospital admission. New diagnostic findings occurred in 11% of patients and only in patients with appropriate studies and an abnormal index echocardiogram. Identification of methods to reduce repeat testing and implement appropriateness criteria is warranted.  相似文献   
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People identified as Very Important Persons (VIPs) often present or are referred to the Emergency Department (ED). Celebrities are a small subset of this group, but many others are included. Triage of these patients, including occasional prioritization, creates practical and ethical challenges. Treatment also provides challenges with the risks of over testing, overtreatment, over consultation, and over or under admission to the hospital. This article presents a practical and ethical framework for addressing the care of VIPs in the ED.  相似文献   
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