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451.
A successful closure of an aneurysmal aorto-right ventricular tunnel (ARVT) in a 16-year-old male patient is reported here. An attempt at device closure had failed in this patient. Diagnosis was confirmed by Doppler echocardiography, 3-dimensional computed tomography, and cardiac catheterization. Surgical closure with a Dacron patch (W.L. Gore & Associates, Flagstaff, AZ) at the aortic end and direct closure at the ventricular end was done successfully with the patient under mild hypothermia. The postoperative echocardiogram showed a competent aortic valve with a closed ARVT.  相似文献   
452.

Background

The purpose of this study was to describe Canadian general surgery residents’ perceptions regarding potential implementation of work-hour restrictions.

Methods

An ethics review board–approved, Web-based survey was submitted to all Canadian general surgery residency programs between April and July 2009. Questions evaluated the perceived effects of an 80-hour work week on length of training, operative exposure, learning and lifestyle. We used the Fisher exact test to compare senior and junior residents’ responses.

Results

Of 360 residents, 158 responded (70 seniors and 88 juniors). Among them, 79% reported working 75–100 hours per week. About 74% of seniors believed that limiting their work hours would decrease their operative exposure; 43% of juniors agreed (p < 0.001). Both seniors and juniors thought limiting their work hours would improve their lifestyle (86% v. 96%, p = 0.12). Overall, 60% of residents did not believe limiting work hours would extend the length of their training. Regarding 24-hour call, 60% of juniors thought it was hazardous to their health; 30% of seniors agreed (p = 0.001). Both senior and junior residents thought abolishing 24-hour call would decrease their operative exposure (84% v. 70%, p = 0.21). Overall, 31% of residents supported abolishing 24-hour call. About 47% of residents (41% seniors, 51% juniors, p = 0.26) agreed with the adoption of the 80-hour work week.

Conclusion

There is a training-level based dichotomy of opinion among general surgery residents in Canada regarding the perceived effects of work hour restrictions. Both groups have voted against abolishing 24-hour call, and neither group strongly supports the implementation of the 80-hour work week.  相似文献   
453.
Calcifying aponeurotic fibroma is a benign tumor with a predilection for distal parts of the extremities; it is very rare in the head and neck region. It commonly affects young patients-hence the term juvenile in the name. It is fibroblastic in origin and considered a cartilage analogue of fibromatosis, but its exact etiology remains unknown. Clinically, this tumor needs to be differentiated from fibromatosis, nodular fasciitis, chondroma, schwannoma, and rheumatoid nodule. A 24-year-old woman presented with swelling in the forehead for the previous 6 months. Wide surgical excision of the lesion was performed, and histopathologic examination revealed a calcifying aponeurotic fibroma. We reviewed the literature on this rare clinical entity and present our hypothesis on its etiology.  相似文献   
454.
BACKGROUND AND OBJECTIVES: A Gonococcal Antimicrobial Susceptibility Program (GASP) under the World Health Organization South East Asia Region (WHO SEAR) is continuing in India and neighboring countries and is being coordinated by the WHO Regional Reference Laboratory (RRL), Vardhman Mahavir Medical College, and Safdarjung Hospital, New Delhi. GOAL: The present communication describes the current status and trends of antimicrobial resistance patterns of Neisseria gonorrhoeae, isolated in different focal-point laboratories under GASP, as presented in WHO SEAR intercountry consultative meeting conducted in December 2001. STUDY: Seven laboratories from India and 1 each from Bangladesh, Sri Lanka, and Nepal presented their data for the year 2000/2001. In addition, RRL Delhi, Bangladesh, and Sri Lanka presented data for the years 1995 to 2001, 1997 to 2001, and 1996 to 2000, respectively. Either National Committee for Clinical Laboratory Standards or calibrated dichotomous sensitivity technique was used in the different laboratories for determining antimicrobial susceptibility. RESULTS: It was observed that in the Indian laboratories, penicillin resistance varied from 20% to 79%, tetracycline resistance from 0% to 45.6%, and ciprofloxacin from 10.6% to 100%. Chromosomal, as well as plasmid-mediated resistance, was observed. The strains were reported to be less sensitive to ceftriaxone in 5 out of 7 laboratories, while none reported spectinomycin resistance. The reasons for wide variation in the results could be due to geographical strain difference in different parts of this vast country. At Sri Lanka, gonococci showed resistance towards penicillin (96.8%) and ciprofloxacin (8.2%). Bangladesh reported N. gonorrhoeae with ciprofloxacin (76%), penicillin (33%), and tetracycline (50%) resistance and decreased susceptibility to ceftriaxone (1.5%). Both the laboratories did not report any spectinomycin resistance. The resistance trends in these 2 centers and the RRL, New Delhi, showed different patterns. CONCLUSION: The report indicates the necessity for continuous surveillance of antimicrobial resistance pattern in this region of WHO for establishing antimicrobial policy guidelines for management of this common but important sexually transmitted infection (STI) pathogen, known to facilitate human immunodeficiency virus (HIV) infection. It also highlights the importance of ensuring quality assurance in the techniques in order to generate uniform data.  相似文献   
455.
Aim: We hypothesized that the implementation of a feeding quality improvement (QI) program among premature neonates accelerates feeding milestones, safely lowering hospital length of stay (LOS) compared with the baseline period. Methods: Baseline data were collected for 15 months (N = 92) prior to initiating the program, which involved development and implementation of a standardized feeding strategy in eligible premature neonates. Process optimization, implementation of feeding strategy, monitoring compliance, multidisciplinary feeding rounds, and continuous education strategies were employed. The main outcomes included the ability and duration to reach enteral feeds–120 (mL/kg/d), oral feeds–120 (mL/kg/d), and ad lib oral feeding. Balancing measures included growth velocities, comorbidities, and LOS. Results: Comparing baseline versus feeding program (N = 92) groups, respectively, the feeding program improved the number of infants receiving trophic feeds (34% vs 80%, P < .002), trophic feeding duration (14.8 ± 10.3 days vs 7.6 ± 8.1 days, P < .0001), time to enteral feeds–120 (16.3 ± 15.4 days vs 11.4 ± 10.4 days, P < .04), time from oral feeding onset to oral feeds–120 (13.2 ± 16.7 days vs 19.5 ± 15.3 days, P < .0001), time from oral feeds–120 to ad lib feeds at discharge (22.4 ± 27.2 days vs 18.6 ± 21.3 days, P < .01), weight velocity (24 ± 6 g/d vs 27 ± 11 g/d, P < .03), and LOS (104.2 ± 51.8 vs 89.3 ± 46.0, P = .02). Mortality, readmissions within 30 days, and comorbidities were similar. Conclusions: Process optimization and the implementation of a standardized feeding strategy minimize practice variability, accelerating the attainment of enteral and oral feeding milestones and decreasing LOS without increasing adverse morbidities.  相似文献   
456.
BACKGROUND: Few studies have evaluated the associations of plasma homocysteine concentration, the methylenetetrahydrofolate reductase (MTHFR) C677T genotype and B vitamin concentration with intima media thickness (IMT) in multiethnic populations. METHODS: In the Study of Health Assessment and Risk in Ethnic groups (SHARE), we measured carotid IMT, fasting serum folate, serum B12, plasma pyridoxal-5'-phosphate (PLP) and plasma homocysteine and determined the MTHFR C677T genotype in a cross-sectional study of 818 South Asian, Chinese and European Canadians without previous history of CVD, cancer or diabetes during 1996-1998. RESULTS: Plasma homocysteine was inversely related to serum folate, serum B12, plasma PLP, B vitamin supplement use and Chinese ethnicity, and was positively associated with hypertension, smoking, IMT, MTHFR 677T/T genotype and South Asian ethnicity. Although ethnicity was not a statistically significant modifier, among carriers of the MTHFR 677T/T genotype with serum folate < or =14 nmol/L compared to >14 nmol/L, plasma homocysteine was significantly higher among South Asians (50.9% increase, P < 0.001) and Europeans (52.4% increase, P < 0.001) but not Chinese (11.0% increase, P > 0.05). Plasma homocysteine > 11.7 micromol/L was associated with a 5.9% (95% CI: 1.9%, 10.0%) increase in IMT (approximately 0.04 mm) in the pooled-data analyses with similar increases noted in the ethnic-specific analyses. The 677T/T genotype was not associated with a significant change in IMT in the pooled-data analyses (2.7%; 95% CI: -1.7%, 7.2%) nor in ethnic-specific analyses compared to other genotypes, although there were only 63 677T/T homozygotes. CONCLUSION: The combination of lower serum folate and the MTHFR 677T/T genotype is associated with increased plasma homocysteine among South Asians and Europeans, but the association is not evident among Chinese possibly because their serum folate may not have been low enough to compromise MTHFR activity. Plasma homocysteine > 11.7 micromol/L appears to be associated with a clinically important increase in IMT.  相似文献   
457.
Kinases are known to regulate fundamental processes in cancer including tumor proliferation, metastasis, neovascularization, and chemoresistance. Accordingly, kinase inhibitors have been a major focus of drug development, and several kinase inhibitors are now approved for various cancer indications. Typically, kinase inhibitors are selected via high-throughput screening using catalytic kinase domains at low ATP concentration, and this process often yields ATP mimetics that lack specificity and/or function poorly in cells where ATP levels are high. Molecules targeting the allosteric site in the inactive kinase conformation (type II inhibitors) provide an alternative for developing selective inhibitors that are physiologically active. By applying a rational design approach using a constrained amino-triazole scaffold predicted to stabilize kinases in the inactive state, we generated a series of selective type II inhibitors of PDGFRβ and B-RAF, important targets for pericyte recruitment and endothelial cell survival, respectively. These molecules were designed in silico and screened for antivascular activity in both cell-based models and a Tg(fli1-EGFP) zebrafish embryogenesis model. Dual inhibition of PDGFRβ and B-RAF cellular signaling demonstrated synergistic antiangiogenic activity in both zebrafish and murine models of angiogenesis, and a combination of previously characterized PDGFRβ and RAF inhibitors validated the synergy. Our lead compound was selected as an orally active molecule with favorable pharmacokinetic properties which demonstrated target inhibition in vivo leading to suppression of murine orthotopic tumors in both the kidney and pancreas.  相似文献   
458.
Hemitruncus is an uncommon congenital anomaly that has been described in isolation or in association with other congenital cardiac malformations. This report describes a rare case of left hemitruncus with tetralogy of Fallot and a right-sided aortic arch. The patient presented to us in the early second decade. The diagnosis was suspected with echocardiography and confirmed with cardiac catheterization. The patient underwent successful surgical correction of the anomaly.  相似文献   
459.
SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis and osteitis) is a rare chronic autoinflammatory disorder of unknown etiology. Radiological investigation, including the use of magnetic resonance imaging and nuclear medicine is pivotal to the diagnosis of SAPHO syndrome. We present a case of a 15-year-old male diagnosed with SAPHO syndrome displaying the classic diagnostic findings of this condition on bone scan and magnetic resonance imaging.  相似文献   
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