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51.
Objectives: As there are some suggestions that a family history of cancer or autoimmune disease might be associated with an increased risk of leukemia in children, we explored this possibility using data from a matched case-control study conducted by the Children's Cancer Group. Methods: We compared the family history of cancer and autoimmune diseases of 302 infant leukemia cases (diagnosed within the first 18 months of life) with that of 668 individually matched controls in the United States and Canada. Results: Although not significant, cancer history in parents was found to be associated with an elevated risk of infant leukemia (odds ratio [OR] = 1.4, 95 percent confidence interval [CI] = 0.6-3.6), predominantly acute myeloid leukemia (AML) (OR = 2.2, CI = 0.6-9.0). Cancer history among second-degree relatives was also related to a non-significantly elevated risk of AML. Family history of autoimmune diseases, on the other hand, was generally not found to be related to the risk of infant leukemia. Conclusion: This study provided no strong evidence that family history of cancer or autoimmune disease is a major risk factor for infant leukemia.  相似文献   
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OBJECTIVE: To report the short- and long-term complications encountered in a large number of consecutive children undergoing implantation in a single center. The current study also describes the management and sequelae of each complication. STUDY DESIGN: Prospective study assessing the surgical findings and complications of deaf children undergoing implantation. SETTING: Pediatric tertiary referral center for cochlear implantation. PATIENTS: The present study includes 300 consecutive children undergoing implantation, with a mean age at implantation of 5.1 years, ranging from 1.3 to 16.9 years. Of these children, 196 (65%) had congenital deafness of unknown cause. The commonest known cause was meningitis (73 of 300 [24%]) followed by congenital cytomegalovirus infection (17 of 300 [6%]). Children have been followed up regularly after implantation, typically at yearly intervals after the first year. The mean duration of follow-up at the time of the study was 4 years (range, 0.1-14 yr). RESULTS: There were no major perioperative (within 1 d after surgery) or major early postoperative (within 1 wk after surgery) complications. In the same periods, there were 19 and 15 minor complications, respectively. These complications (e.g., eardrum perforation, hematoma, flap swelling, wound infection, temporary facial weakness) settled with conservative treatment or minor intervention. With regard to the late surgical complications (>1 wk after surgery), there were 7 major (e.g., severe flap infection requiring explantation, cholesteatoma, persistent eardrum perforation) and 14 minor complications (e.g., mild flap infection, flap swelling, hematoma). A number of complications were encountered even 14 years after the original operation, and some of them needed repeated interventions, highlighting the importance of long-term follow-up. However, most of the complications occurred very close to the surgical procedure (<1 yr). CONCLUSION: An overall rate of 2.3% for major surgical complications and an overall rate of 16% for minor surgical complications suggest that cochlear implantation is a relatively safe surgical operation in experienced centers. Most surgical complications are minor and can be managed with conservative treatment or minor surgical intervention. However, meticulous attention to surgical detail, especially handling soft tissues and leaving the posterior canal wall intact, and long-term follow-up are of paramount importance in minimizing the incidence of surgical complications.  相似文献   
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Self‐reported measures of health, in the context of developed countries, are well‐researched and commonly regarded as reliable predictors of the underlying health of the population. However, the validity of these measures is under‐researched and questionable in the context of low‐ and middle‐income countries. The authors used Longitudinal Ageing Study in India (LASI) survey data from India to compare self‐reported hypertension with biometrically‐measured hypertension. The results are reported in terms of sensitivity, specificity, and kappa as a measure of agreement. Logistic regression was undertaken to examine the characteristics of those who were unaware of their hypertensive status. Our analysis showed a low sensitivity of 56% and a high specificity of 90.5%. Agreement between self‐reported data and biometric measurement of hypertension was observed to be moderate (κ = 0.48). Large variations were observed among states and sub‐groups. The odds of false negative reporting of hypertension were lower in the individuals with higher age, high education, and greater wealth status. The authors conclude that self‐reported hypertension has important limitations and may be a source of systematic bias. It is recommended that planning and policy‐making in India be based more on an objective assessment of hypertension.  相似文献   
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The ongoing evolution of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has resulted in the recent emergence of a highly divergent variant of concern (VOC) defined as Omicron or B.1.1.529. This VOC is of particular concern because it has the potential to evade most therapeutic antibodies and has undergone a sustained genetic evolution, resulting in the emergence of five distinct sub-lineages. However, the evolutionary dynamics of the initially identified Omicron BA.1 and BA.2 sub-lineages remain poorly understood. Herein, we combined Bayesian phylogenetic analysis, mutational profiling, and selection pressure analysis to track the virus’s genetic changes that drive the early evolutionary dynamics of the Omicron. Based on the Omicron dataset chosen for the improved temporal signals and sampled globally between November 2021 and January 2022, the most recent common ancestor (tMRCA) and substitution rates for BA.1 were estimated to be that of 18 September 2021 (95% highest posterior density (HPD), 4 August–22 October 2021) and 1.435 × 10−3 (95% HPD  =  1.021 × 10−3 − 1.869 × 10−3) substitution/site/year, respectively, whereas 3 November 2021 (95% highest posterior density (HPD) 26 September–28 November 2021) and 1.074 × 10−3 (95% HPD  =  6.444 × 10−4 − 1.586 × 10−3) substitution/site/year were estimated for the BA.2 sub-lineage. The findings of this study suggest that the Omicron BA.1 and BA.2 sub-lineages originated independently and evolved over time. Furthermore, we identified multiple sites in the spike protein undergoing continued diversifying selection that may alter the neutralization profile of BA.1. This study sheds light on the ongoing global genomic surveillance and Bayesian molecular dating analyses to better understand the evolutionary dynamics of the virus and, as a result, mitigate the impact of emerging variants on public health.  相似文献   
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Purpose:The current study was aimed at assessment of optic disk by disk damage likelihood scale (DDLS) staging using slit-lamp biomicroscopy and optical coherence tomography (OCT) in diagnosing primary open-angle glaucoma (POAG) patients.Methods:This was a cross-sectional observational study of 106 POAG patients, which was conducted from April 2017 to April 2018. All patients underwent slit-lamp fundoscopy with a +78 D lens and high-definition (HD)-OCT, and the vertical cup disk ratios (VCDRs) were recorded. Disk size and neuroretinal rim assessment were done, and the disk was then staged using the recent version, which stages the optic nerve head (ONH) from 1 to 10 as read from the DDLS nomogram table. DDLS scores >5 indicate glaucomatous damage. Pearson coefficient was used to correlate the DDLS staging by slit-lamp biomicroscopy with best-corrected visual acuity (BCVA), intraocular pressure (IOP), disk size, and VCDR and VCDR, mean deviation, and DDLS staging by HD-OCT.Results:The mean age of the patients was 59.54 ± 6.61 years. The male: female ratio was 2:1. The mean IOP was 16.04 ± 1.97 mmHg, and BCVA was 0.72 ± 0.13 LogMAR units. The mean VCDR on 78 D slit-lamp biomicroscopy was 0.76 ± 0.09 (standard deviation [SD]) (range 0.1–0.77), whereas on HD-OCT, the mean VCDR was 0.81 ± 0.09 (SD) (range 0.07–0.81). The mean deviation on visual field testing in decibels was −14.43 ± 3.31 (SD). The correlation coefficient between DDLS staging by slit-lamp biomicroscopy and DDLS staging by HD-OCT parameters was r = 0.96.Conclusion:There is a positive correlation between the DDLS system of optic disk evaluation on slit-lamp biomicroscopy and most of the HD-OCT evaluation parameters.  相似文献   
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ObjectiveWe evaluated the accuracy and feasibility of transcutaneous laryngeal ultrasonography as an alternative to videolaryngoscopy for assessing vocal cord mobility to rule out recurrent laryngeal nerve injury following thyroidectomy.MethodsForty-five adult patients scheduled to undergo elective thyroidectomy under general anesthesia were included. Preoperatively, indirect laryngoscopy and transcutaneous laryngeal ultrasonography was done for assessing vocal cord mobility. Intraoperatively, following induction, patients were intubated using videolaryngoscope. On completion of the surgical procedure, one anesthetist performed videolaryngoscopy so as to record vocal cord mobility while the patients were being extubated in deep plane of anesthesia. Simultaneously another anesthesiologist performed transcutaneous laryngeal ultrasonography.Vocal cord mobility, changes in hemodynamics and total time duration for the two procedures was recorded. Indirect laryngoscopic assessment and flexible fiberoptic laryngoscopy was done on postoperative day 1 and 7 respectively.ResultsPostoperative videolaryngoscopy picked up bilaterally mobile vocal cords in 88.8% cases. Transcutaneous laryngeal ultrasonography could correctly identify 39(86.6%) of these patients, with 1(2.5%) patient being misdiagnosed as having bilaterally immobile vocal cords. Further, videolaryngoscopy identified 5 patients of vocal cord palsy, of which transcutaneous laryngeal ultrasonography correctly identified 3 (60%) patients. Hence, in comparison to videolaryngoscopy, the sensitivity, specificity, positive predictive value, and negative predictive value of transcutaneous laryngeal ultrasonography for assessment of vocal cords was 75%, 95.1%, 60%, and 97.5% respectively.ConclusionIn patients undergoing thyroidectomy, transcutaneous laryngeal ultrasonography can serve as a non-invasive, bedside screening tool for assessing vocal cord palsy postoperatively.  相似文献   
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