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51.

Background

Positive correlation between the orthopedic in-training examination (OITE) and success in the American Board of Orthopaedic Surgery examination has been reported. Canadian training programs in internal medicine, anesthesiology and urology have found a positive correlation between in-training examination scores and performance on the Royal College of Physicians and Surgeons of Canada (RCPSC) certification examination. We sought to determine the potential predictive value of the OITE scores of Canadian orthopedic surgery residents on their success on their RCPSC examinations.

Methods

A total of 118 Canadian orthopedic surgery residents had their annual OITE scores during their 5 years of training matched to the RCPSC examination oral and multiple-choice questions and to overall examination pass/fail scores. We calculated Pearson correlations between the in-training examination for each postgraduate year and the certification oral and multiple-choice questions and pass/fail marks.

Results

There was a predictive association between the OITE and success on the RCPSC examination. The association was strongest between the OITE and the written multiple-choice examination and weakest between the OITE and the overall examination pass/fail marks.

Conclusion

Overall, the OITE was able to provide useful feedback to Canadian orthopedic surgery residents and their training programs in preparing them for their RCPSC examinations. However, when these data were collected, truly normative data based on a Canadian sample were not available. Further study is warranted based on a more refined analysis of the OITE, which is now being produced and includes normative percentile data based on Canadian residents.  相似文献   
52.
Coronary spasm during coronary angiography for vasculopathy in children can be prevented by the intracoronary administration of nitroglycerin. We reviewed the anesthesia and catheterization reports and charts for pediatric transplant recipients who underwent angiography from 2005 through 2010. Correlation analysis was used to study the relation of post-injection systolic blood pressure (SBP) to nitroglycerin dose. Forty-one angiographic evaluations were performed on 25 patients (13 male and 12 female). Mean age was 9.9 ± 3.2 years (range, 3.3–16.1 yr). The mean total dose of nitroglycerin was 2.93 ± 1.60 µg/kg (range, 1–8 µg/kg).There was a significant drop between the baseline SBP (mean, 106 ± 21.6 mmHg) and the lowest mean SBP before nitroglycerin administration (78 ± 13.2, P <0.0001, paired t test). There was no significant additional change in SBP (mean after nitroglycerin administration, 80.7 ± 13.1 mmHg; P = 0.2). There was a significant drop in lowest heart rate between baseline (109 ± 16.5 beats/min) and before nitroglycerin administration (89 ± 14.3 beats/min; P <0.0001, paired t test). There was no significant additional change in heart rate (mean heart rate after nitroglycerin, 84 ± 17.7 beats/min; P = 0.09). There were 2 interventions for SBP before nitroglycerin and 2 after nitroglycerin. One child experienced a transient ST-T–segment change during angiography after nitroglycerin. In the highest dose range, the additional decrease in SBP was 7.2 mmHg (P=0.03). Routine intracoronary nitroglycerin administration in this dose range produced no significant changes in SBP or heart rate in children.Key words: Child, coronary angiography, coronary vasospasm/etiology, dose-response relationship, drug, heart transplantation/adverse effects, hemodynamics/drug effects, nitroglycerin/administration & dosage/therapeutic use, postoperative complications/therapy, retrospective studies, vasodilation/drug effectsAllograft coronary disease in children occurs with increasing frequency after transplantation, as a function of time. In a multicenter study,1 the incidence of coronary artery disease in children 5 years post-transplant was 17% of all recipients. Coronary angiography remains the gold standard in the detection of vasculopathy in heart-transplant recipients.2 Coronary artery spasm can complicate selective coronary angiography and result in myocardial ischemia. Coronary spasm can simulate the angiographic appearance of graft vasculopathy and cause diagnostic confusion.3 The spasm can arise from manipulation of the arterial wall by the catheter or from intraluminal injection of contrast material. In cardiac transplant recipients, coronary artery spasm has been reported in as many as 4.9% of coronary angiograms.3In adults, intracoronary nitroglycerin is routinely administered during coronary angiography to prevent coronary artery spasm.4 In children, however, safety and dosage guidelines for intracoronary nitroglycerin have not yet been firmly established. A dose of 3 µg/kg can be extrapolated by weight from the established adult dose of 200 µg; this dose was used in a study of children after the arterial switch operation and was shown to produce coronary vasodilation—with a small reduction in systolic blood pressure (SBP) and no noteworthy change in heart rate—in a control group of patients.5,6We previously reported a case of coronary artery spasm during routine coronary angiographic monitoring in a 9-year-old boy who had undergone heart transplantation as an infant.7 After left main coronary artery injection of contrast material, the patient''s left anterior descending and left circumflex coronary arteries appeared to be diffusely narrow, and he developed marked ST-segment elevation, hypotension, and ventricular tachycardia. After cardiopulmonary resuscitation, he recovered uneventfully and displayed normal systolic function. Coronary angiography one month later, with the administration of intracoronary nitroglycerin before the injection of contrast material, revealed normal coronary artery diameter and was accomplished without complication.Since 2005, intracoronary nitroglycerin has routinely been used in pediatric transplant patients during biennial selective coronary angiographic monitoring at our institution. The purpose of the study is to report our experience with the routine use of intracoronary nitroglycerin for coronary angiography in children: its effects on blood pressure, on heart rate, and on the occurrence of arrhythmia and ST-segment elevation.  相似文献   
53.
Achromobacter xylosoxidans is part of an emerging group of Gram negative bacterial infections with potentially severe sequelae, especially in the immunocompromised population such as burn patients. While antimicrobial therapy for patients with A. xylosoxidans bacteremia has been reported, the literature is scarce with regard to treatment in patients with positive tissue cultures only. Herein, we report our institution''s experience with such a case and a brief review of the current literature on this micro-organism in the setting of non-bacteremic infection.KEY WORDS: Achromobacter xylosoxidans, alcaligenes xylosoxidans, burn, tissue culture  相似文献   
54.
The rare situation of thyroid stone is discussed with literature review and case report. A case of isolated solitary stone of the thyroid is documented here. There are incidences of calcification in the thyroid gland commonly associated with carcinoma thyroid and multinodular goiter. But solitary stone of thyroid is reported rarely and one such case is reported from India. The possibility of malignancy is high, in case of calcification of thyroid swellings. Hence, isolated calcification should be surgically treated even if fine needle aspiration cytology is negative for malignancy.  相似文献   
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The unique ability of olfactory neurons to regenerate in vitro has allowed their use for the study of olfactory function, regeneration, and neurodegenerative disorders; thus, characterization of their properties is important. This present study attempts to establish the timeline of structural (protein expression) and functional (odorant sensitivity) maturation of human olfactory epithelial cells (hOE) in vitro using biopsy‐derived cultured tissue. Cells were grown for 7 days; on each day, cells were tested for odorant sensitivity using calcium imaging techniques and then protein expression of each cell was tested using immunocytochemistry for proteins typically used for characterizing olfactory cells. Previous studies have shown that mature olfactory neurons in vitro attain a unique “phase‐bright” morphology and express the olfactory marker protein (OMP). By day 3 in vitro, a variety of cells were odorant‐sensitive, including both “phase‐bright” and “phase‐dark” cells that have previously been considered glial‐like cells. The functional maturation of these hOEs appears to take place within 4 days. Interestingly, the emergence of an odorant sensitivity profile of both phase‐bright and phase‐dark cells preceded the expression of marker protein expression for OMP (which is expressed only by mature neurons in vivo). This structural maturation took 5 days, suggesting that the development of odorant sensitivity is not coincident with the expression of marker molecules that are hallmarks of structural maturation. These results have important implications for the use of hOEs as in vitro models of olfactory and neuronal function. © 2013 Wiley Periodicals, Inc.  相似文献   
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Targeting stathmin in prostate cancer   总被引:4,自引:0,他引:4  
Stathmin is the founding member of a family of microtubule-destabilizing proteins that regulate the dynamics of microtubule polymerization and depolymerization. Stathmin is expressed at high levels in a variety of human cancers and provides an attractive molecule to target in cancer therapies that disrupt the mitotic apparatus. We developed replication-deficient bicistronic adenoviral vectors that coexpress green fluorescent protein and ribozymes that target stathmin mRNA. The therapeutic potential of these recombinant adenoviruses was tested in an experimental androgen-independent LNCaP prostate cancer model. Adenovirus-mediated transfer of anti-stathmin ribozymes resulted in efficient transduction and marked inhibition of stathmin expression in these cells. Cells that were transduced with the anti-stathmin adenoviruses showed a dramatic dose-dependent growth inhibition. This was associated with accumulation of LNCaP cells in the G2-M phases of the cell cycle. A similar dose-dependent inhibition of clonogenic potential was also observed in cells infected with anti-stathmin adenoviruses. Morphologic and biochemical analysis of infected cells showed a marked increase in apoptosis characterized by detachment of the cells, increased chromatin condensation, activation of caspase-3, and fragmentation of internucleosomal DNA. If these findings are confirmed in vivo, it may provide an effective approach for the treatment of prostate cancer.  相似文献   
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