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51.
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Computer-aided navigation and robotic guidance systems have become widespread in their utilization for spine surgery. A recent innovation combines these tw  相似文献   
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Smoking and alcohol exposure continue to be the dominant risk factors for the development of head and neck squamous cell carcinoma (SCCHN) worldwide. Moreover, human papillomavirus (HPV) is associated with SCCHN, particularly SCC of the oropharynx (SCCOP). Body mass index (BMI) has been reported as a possible risk factor for SCCHN, yet the data available so far about the relationship between BMI and SCCHN risk have been mixed. We sought to clarify this relationship. BMI and demographic, clinical, and epidemiological information at diagnosis were collected from 2310 SCCHN cases and 1915 controls (who were cancer-free) from October 2001 through May 2013. The odds ratios (ORs) and 95 percent confidence intervals (95% CI) were determined using the logistic regression process. Multivariable models were used to evaluate the strength of the relation between BMI and SCCHN risk. At diagnosis, 64 (2.8%) of the cases were underweight (BMI <18.5 kg/m2), 661 (28.6%) were normal weight (BMI 18.5<25 kg/m2), 833 (36.1%) were overweight (BMI 25<30 kg/m2), and 752 (32.6%) were obese (BMI ≥30 kg/m2). Comparatively, the ORs (95% CIs) for SCCHN associated with being underweight, overweight, and obese were 2.6 (1.54.7), 0.7 (0.6-0.8), and 0.8 (0.7-0.9), respectively, after adjusting for age, gender, race/ethnicity, smoking, and alcohol consumption. On analysis stratified by tumor sites, the risk of SCCOP among patients seropositive for HPVE6 and/or HPVE7 was higher among the overweight (OR, 5.4, 95% CI, 1.3-23.1) and obese patients (OR, 2.4, 95% CI, 1.1-7.6) compared to the normal weight patients. These findings suggest that pretreatment BMI could be a major risk factor for SCCHN, and the association between BMI and HPV may increase the risk of SCCOP.  相似文献   
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Background: Methotrexate is the most common first-line chemotherapy for low-risk gestational trophoblastic neoplasia (GTN). Uterine artery pulsatility index (UAPI) is an ultrasound marker for tumor vascularity that has been associated with an increased risk of methotrexate resistance. The combination of circulating angiogenic factor levels with UAPI data may improve the capacity of this model to predict chemoresistance. Methods: This was a single-center cohort study of women newly diagnosed between January 2008 and June 2012 with low-risk GTN during postmolar surveillance and treated with single-agent methotrexate at Charing Cross Hospital, a UK national center for treatment of gestational trophoblastic disease. Two hundred seventeen women underwent an ultrasound for UAPI measurement prior to initiation of chemotherapy. To examine serologic markers of methotrexate resistance among this cohort, we performed a case-control study using archived serum from 76 patients who could be matched based on prognostic risk score. Serum samples were examined by immunoassay to measure 8 different angiogenic factors (VEGF-A, FGF-basic, PLGF-1, PDGF-BB, EGF, ANGPT2, BMP-9, and ENG). Receiver-operator characteristic area under the curve (AUC) values were calculated for the ability of each analyte to correctly classify patients as methotrexate sensitive (MTX-S) or resistant (MTX-R). Results: Total human chorionic gonadotropin levels were similar between the MTX-S and MTX-R groups. UAPI values were significantly higher in MTX-S (median 1.30 [interquartile range {IQR} = 0.80-1.90]) compared to MTX-R patients (median 0.875 [IQR = 0.60-1.30]; P < 0.0001) with AUC 0.68 (95% confidence interval 0.61-0.76; P < 0.0001). In univariate analysis, only BMP-9 concentrations were significantly different between groups, lower among MTX-S (median of 225 ng/L, IQR = 170-287) compared to MTX-R patients (median 280 ng/L [IQR = 200-339]; P= 0.03). Combining UAPI with BMP-9 concentration improved prediction for chemoresistance with AUC 0.77 (95% confidence interval 0.66-0.88; P < 0.0001). Conclusion: Circulating levels of BMP-9 are elevated in newly diagnosed women with low-risk GTN destined to fail primary methotrexate therapy. A combined test using serum BMP-9 plus UAPI might improve prediction of MTX-R in low-risk GTN.  相似文献   
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Although catheter-based intervention is generally accepted as the treatment of choice for branch pulmonary artery (PA) stenosis, there are no data directly comparing both the need for reintervention and time to reintervention in patients undergoing transcatheter stenting versus surgical arterioplasty. We compared children who underwent surgical branch pulmonary arterioplasty and branch PA stent placement between January 2008 and May 2012 at a single tertiary center. Need for reintervention and mean time to reintervention were assessed using chi-square and independent sample Student t test. Thirty-seven patients were included (surgery n = 18, stent n = 19). Mean weight at initial intervention was 11.3 ± 8.8 kg for surgical and 20.1 ± 15.5 kg for stent (p = 0.041). Intervention was performed on the left PA in 17 patients, the right PA in 12 patients, and both PAs in 8 patients. Five patients had undergone previous intervention. On mean follow-up of 807 ± 415 days, 50 % (9 of 18) of the surgery cohort and 5.3 % (1 of 19) of the stent cohort required reintervention (p = 0.002). In all but one case reintervention was catheter-based. Mean time to reintervention for the surgery cohort was 272 ± 162 days and for the single stent cohort it was 150 days. When comparable age and weight groups were analyzed, reintervention was still more common in the surgery cohort (p = 0.007). Children undergoing surgical branch pulmonary arterioplasty are more likely to require reintervention than those undergoing stent placement.  相似文献   
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Infants with significant congenital heart disease (CHD) typically require transport from their birth centre to a regional paediatric cardiac centre. Antenatal diagnosis of CHD allows early pre-emptive stabilisation, and is associated with improved early clinical status. However, the effect of antenatal diagnosis on the transport characteristics of infants with CHD has not been previously investigated. The aim of this study was to compare the transport characteristics of infants with antenatal and postnatal diagnosis of CHD. This study is a retrospective cohort study of all infants of ≤10 days and ≥34 weeks of gestation with CHD admitted to the Royal Children's Hospital, Melbourne (RCH) over 5 years. Demographic, diagnosis, and transport data were recorded. Cases of complex CHD were included in this study. Of 320 infants with complex CHD, 198 (62 %) had antenatal diagnosis (ANdx) and 122 (38 %) had postnatal diagnosis (PNdx). There was no significant difference in sex, birth weight, or gestation between ANdx and PNdx groups. Average age of referral was 15 vs. 53.4 h in ANdx vs. PNdx groups. Aggregate transfer distance in the ANdx group was 2216 km and in the PNdx group was 10,274 km (P?<?0.0001). Of the infants, 39 % in the PNdx group required highest-acuity “time critical” transports compared to 6 % of ANdx infants (P?=?0.0001). Conversely, only 11 % of the infants in the PNdx group had lowest acuity “non-urgent” transfers, compared to 24 % of ANdx infants (P?=?0.003). PNdx was associated with significantly higher rates of invasive ventilation (36 vs 20 %; P?=?0.01) and higher rates of inotrope use (19 vs. 9 %; P?=?0.007) during transport. Conclusions: Improved antenatal detection would allow for safer, less resource intense transfers of infants with CHD.  相似文献   
59.
OBJECTIVES: To evaluate the outcome of arterially enhancing nodules (AENs) measuring <20 mm detected on MRI in patients with cirrhosis. METHODS: Prospective analysis of 54 patients with a total of 161 AENs <20 mm on MRI. Inclusion criteria included a minimum of 12 months of MRI follow-up or histological evaluation of the AEN. Key exclusions were patients with an AEN >20 mm or prior diagnosis of HCC. Two radiologists blinded to the clinical and pathological data reviewed serial MRIs and classified the AENs as no longer visible, stable, increasing, or decreasing in size. RESULTS: A total of 161 AENs were identified and were followed by serial MRI for a mean of 24 months. Eighty (50%) AENs were no longer visible on repeat imaging, 42 (26%) remained stable, 1 of which was diagnosed as HCC on short-term follow-up, 8 (5%) increased in size and were subsequently diagnosed as HCC, and 24 (15%) decreased in size. In addition, 7 AENs (4%) were diagnosed on biopsy immediately following the initial MRI. Overall MR characteristics diagnostic of HCC were growth > or =2 mm and peripheral rim enhancement on initial MRI. CONCLUSIONS: The majority (90%) of AENs <20 mm in cirrhosis are benign. The presence of rim enhancement or interval growth of an AEN are suggestive of HCC.  相似文献   
60.
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