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1.
OBJECTIVE: There are several modifications introduced in the preparation for a subsequent non-surgical transcatheter completion of the Fontan procedure. We report our experience with one type of the modification and the short-term results following its implementation. METHODS: During bidirectional cavopulmonary connection (BCPC) an intra-atrial lateral tunnel is additionally created, as intended for a Fontan procedure but fenestrated with a 10-14 mm aperture. The cardiac end of the superior vena cava (SVC) is then patched to maintain the physiology of BCPC. During the interventional transcatheter completion procedure, the SVC patch is perforated using radio-frequency (RF) energy, balloon-dilated, and stented as well. The aperture is closed with a device when required. Paired t-test was used to compare data before and after the Fontan completion. RESULTS: From June 2003 to February 2006, 16 patients (9 boys and 7 girls, mean age 12 months) underwent the surgical procedure described. The mean bypass time was 137 min and the mean ischemic time was 77 min. There were no operative deaths. One patient with bilateral SVC required a take down due to recurrent effusions. Ten months later, nine patients underwent completion (mean age 20 months, mean weight 10.6 kg). The stents were dilated to a mean diameter of 14.4mm. All except one aperture was closed with a device. The mean fluoroscopy time was 41 min. Oxygen saturation increased from 85 to 94% (p=0.001). Pulmonary artery pressures remained normal (16 mmHg before and 19 mmHg after, p=0.12). No patients required mechanical ventilation and none developed pleural effusions or arrhythmias. All were discharged from hospital within 6 days of the Fontan completion. Twenty-two months after Fontan, all were well. Echocardiography revealed no gradients across the stents. Two patients had minor leaks across the aperture. One underwent further stent dilatation a year later. CONCLUSIONS: Fontan completion without surgery is suitable in patients with single ventricles with lower mortality and morbidity, avoids multiple surgical interventions while maintaining the staged approach and allows for successive dilatation of the Fontan pathway to accommodate for growth.  相似文献   
2.

Background

Hospital readmissions are an increasingly scrutinized marker of surgical care delivery and quality. There is a paucity of information in the literature regarding the rate, risk factors, and common causes of readmission after surgery for sinonasal cancer.

Methods

We analyzed the Nationwide Readmissions Database for patients who underwent surgery for a diagnosis of sinonasal cancer between 2010 and 2014. Rates, causes, and patient‐, procedure‐, and hospital‐level risk factors for 30‐day readmission were determined. Multivariate logistic regression was used to identify predictors of 30‐day readmission.

Results

Among the 4173 cases, the 30‐day readmission rate was 11.6%, with an average cost per readmission of $18,403. The most common readmission diagnoses were wound complications (15.3%) and infections (13.4%). On multivariate regression, significant risk factors for readmission were chronic renal failure (odds ratio [OR], 2.95; 95% confidence interval [CI], 1.41‐6.17), involvement of the skull base or orbit (OR, 1.67; 95% CI, 1.11‐2.51), nonelective initial surgical admission (OR, 2.35; 95% CI, 1.42‐3.89), and length of stay ≥7 days (OR, 1.87; 95% CI, 1.14‐3.05).

Conclusion

Through the use of a large national database, we found that approximately 1 in 9 patients undergoing surgery for sinonasal cancer was readmitted within 30 days. Readmissions were most commonly associated with wound complications and infections. Factors related to procedural complexity were more important predictors of readmission than patients’ demographics or comorbidities.
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3.
Objectives To profile the clinical presentation and treatment results of esthesioneuroblastomas at the University of California, Los Angeles (UCLA), from 2002 to 2013. Design Retrospective review. Setting Tertiary academic institution. Participants Forty-one patients with esthesioneuroblastomas treated at UCLA. Main Outcome Measures Overall survival (OS) and recurrence-free survival (RFS). Results Thirty-six patients were included with a mean age of 50.1 years and a median duration of follow-up of 33 months. The 5-year RFS and OS were 54% and 82%, respectively. Modified Kadish stage was the only factor identified to affect OS. Multivariate analysis demonstrated that tumor grade was the only factor that had an independent impact on RFS. There was no statistical difference in survival among the surgical approaches chosen. Conclusions The updated data on the UCLA experience reveals that all three surgical approaches chosen provide comparable survival, although longer follow-up will be needed to ascertain if these findings hold true. The endoscopic approach had a statistically significant decrease in length of hospital stay and a trend toward reduced blood loss, intensive care unit admission, and complications. The modified Kadish staging was the only factor identified to predict OS. Multivariate analysis revealed that tumor grade was an independent predictor of recurrence; therefore, its importance should be emphasized in future staging systems.  相似文献   
4.
AIM: The objective of this article is to present a simple technique for stabilizing a lingual fixed retainer wire in place with good adaptation to the teeth surfaces and checking for occlusal interferences prior to the bonding procedure. BACKGROUND: Bonding of an upper or lower fixed lingual retainer using stainless steel wires of different sizes and shapes is a common orthodontic procedure. The retainer can be constructed in a dental laboratory, made at chair side, or it can be purchased in prefabricated form. All three ways of creating a fixed retainer are acceptable. However, the method of holding the retainer wire in place adjacent to the lingual surfaces of the teeth before proceeding with the bonding process remains a problem for some practitioners. REPORT: The lingual fixed retainer was fabricated using three pieces of .010" steel ligature wire which were twisted into a single strand wire. Another four to five 0.010" pieces of steel ligature wires were twisted in the same way to serve as an anchor wire from the labial side of the teeth. The retainer wire was bonded using the foible composite. SUMMARY: The technique presented here for stabilizing the retainer wire prior to bonding provides good stabilization, adaptation, and proper positioning of the retainer wire while eliminating contamination of etched surfaces which might arise during wire positioning before bonding. This technique also allows the clinician the opportunity to check the occlusion and adjust the retainer wire to avoid occlusal interference prior to bonding maxillary retainers. This same clinical strategy can be used to stabilize wires for splinting periodontally affected teeth and traumatized teeth.  相似文献   
5.
A ubiquitous environmental toxicant – lead is known to affect several organ systems. This study was designed to investigate the effects of lead nitrate exposure on liver structure and DNA fragmentation. Adult male Wistar rats were treated orally with lead nitrate at the dose levels of 0%, 0.5% and 1% for 60 days and sacrificed on the next day. The liver was processed for thick sections and evaluated after toludine blue staining and by electron microscopy after staining with uranyl acetate and lead citrate. The DNA damage was assessed by DNA fragmentation assay. The liver weight was not significantly affected in the experimental groups. Hepatocyte nuclei were not shrunk, instead lead was mitogenic to hepatocytes as indicated by an increase in the number of binucleated hepatocytes (P<0.05). The number of mitochondria per hepatocyte decreased in a dose-dependent manner (P<0.05). Qualitatively, the necrotic changes such as small to large-sized cytoplasmic vacuoles often displacing the organelles, decrease in hepatocyte microvilli, degeneration of mitochondria, and vacuolar encroachment of nuclei and dilatation of sinusoids were observed. The qualitative changes were induced in a dose-dependent manner. Kupffer cells or Ito cells did not present any notable structural changes. Although the electrophoretic flow of DNA fragments was observed in lead-treated groups, these changes were not significantly different from that in control as evaluated by optical density. In conclusion, lead induces necrotic changes with simultaneous mitogenic activity; however, it does not induce significant DNA damage in the liver.  相似文献   
6.
In this article, we examine the communication of health risks caused by technological and natural disasters to the public. Contrary to the commonly accepted view, we argue that in the context of the risk society, the transformation and multiplication of risk messages among the public is a healthy sign. We aim to show how the recipients of risk communication can overcome the confusion that emanates from the inevitable contradictions of warning messages. We used Luhmann’s communication theory to develop a model of the analysis of personal interpretations of warning messages and examined how this explained the variations in the personal sense of risk that shaped the reception of a warning message. Our model developed Luhmann’s concepts of first- and second-order observations: direct and reflective approaches to risk messages. Using data derived from seven focus groups conducted in four Estonian cities in 2009–2010, we examined how the choice between direct and reflective approaches to risk messages was dependent on recipient’s reflection of social relations in the messages and the channels of their delivery. We found that the first response to the warning message depended on whether the information could be dealt with by first-order observation. When members of the focus group realised they needed to use a second-order observation strategy, they tended to use emotions to respond to risk messages. Our data show that defining risks and legitimising solutions in a collective discussion tended to be more important for an individual than accessing the one-dimensional official constructions of risks.  相似文献   
7.
8.
The Antineuroblastoma monoclonal antibody CNM-5 was submitted to preclinical studies and then used for tumor imaging with following results. 1. CNM-5 is an antibody which belongs to the IgM fraction and has a molecular weight of 900 kilodaltons. Its protein concentration was found to be 17.99 mg/dl. 2. The 131I-labeled antibody was injected into nude mice transplanted with human neuroblastoma, and imaging was performed by a gamma camera. Accumulation of 131I in the tumor was relatively clearly seen. Various organs were removed and examined for 131I uptake. Radioactivity was easily detected in the tumor, suggesting that CNM-5 is effective for use in imaging diagnosis of neuroblastoma.  相似文献   
9.
Attempts at classification of fronto-temporal dementias have not yet been completely successful. We report ten cases of sporadic fronto-temporal dementia (FTD) with ubiquitin-positive neuronal inclusions in cortex or in motor neurons in brain stem or spinal cord, which may contribute to the classification of FTD. Marked variation in clinical presentation as well as in pathological findings was the rule in all cases. Dementia was a prominent feature. Only one case had clinical features suggestive of motor neuron disease. Three of four younger onset cases displayed an especially severe atrophy of the temporal lobes, the basal ganglia and the substantia nigra. This contrasted with the other seven cases in which the fronto-temporal atrophy and changes in basal ganglia and substantia nigra were variable and sometimes mild. In addition to the presence of ubiquitin-reactive, but tau-and silver impregnation-negative neuronal inclusions, all cases demonstrated tau 2-positive glial inclusions, similar to those recently reported in three motor neuron disease cases with dementia. The glial inclusions were not visible with antibody to tau 1. Reaction with antibody to alpha-synuclein was invariably negative. If the combination of ubiquitin-positive neuronal and tau 2-positive glial inclusions is found to be consistently present in FTD of motor neuron type, this feature will provide a firmer basis for this diagnosis than previously available.  相似文献   
10.
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