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91.
IntroductionCurrently information regarding burn size from referring departments to burn centres varies in accuracy. Inaccurate assessment of burn size can lead to over or under treatment. Photographs of injuries may improve accuracy of assessment. We aimed to assess the accuracy of measuring burn size on a static image by including a standard object in the image.MethodsSimulated burn areas were drawn on different body parts of the model. Using an iPhone® model 5 s with an 8 megapixel camera we took photos of the marked area, and repeated them with the palm, a standard bank card and a penny in the picture. First the Du Bois formula, was used to calculate body surface area. Members of the Burns team were asked to view the photos (n = 30) and estimate the percentage of the simulated burn.ResultsWe found an overall overestimation of burn size. Small areas of the forearm were better estimated and within 1.1% of the calculated surface area, however we found no improvement when using a standard object in these images. The back areas were most overestimated ranging from 0.9%–8.9% despite all being the same sized area.ConclusionsStatic images tend to overestimate burn size despite the use of a standard object in the image.  相似文献   
92.
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (< 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT.  相似文献   
93.
BackgroundRadiotherapy after breast-conserving surgery (BCS) is not always necessary in older women staged T1N0M0 with low-risk invasive breast cancer, but few studies have concluded the detailed tumor size as a reference for avoiding radiotherapy. The study was conducted to explore and identify the optimal cutoff tumor size.MethodsThe study population was from the Surveillance, Epidemiology, and End Results (SEER) database in 2010–2016. Propensity score matching was used to balance the confounders between groups. Predictors associated with survival were analyzed by Kaplan–Meier, X-tile, Cox proportional hazards model and competing risk model.ResultsA total of 52049 women and 3846 deaths were included in the cohort with a median follow-up of 34 months. Based on the cutoff value determined by X-tile analysis, the study population were divided into small tumor group (≤14 mm in diameter) and large tumor group (>14 mm in diameter). Small tumors and radiotherapy were correlated with better breast cancer-specific survival (BCSS). In subgroup analysis, the absolute benefit of BCSS in 6 years attributed to radiotherapy was only 0.90% (RT vs. non- RT:98.77% vs. 97.87%) for patients with small tumors but up to 3.33% (RT vs. non- RT:97.10% vs. 93.77%) for those with large tumors.ConclusionSmall tumors and adjuvant radiotherapy were associated with improved long-term prognosis, and 14 mm in diameter was the cutoff tumor size of omitting radiotherapy for patients aged 65 or older with T1N0M0 stage, ER+ and HER2-breast carcinoma after BCS.  相似文献   
94.
There is a paucity of data on the outcome of liver transplantation (LT) in Budd-Chiari Syndrome (BCS) patients who are listed as status 1. The objective of our study was to determine patient or graft survival following LT in status 1 BCS patients. We utilized United Network for Organ Sharing (UNOS) database to identify all adult patients (> 18 years of age) listed as status 1 with a primary diagnosis of BCS in the United States from 1998 to 2018, and analyzed their outcomes and compared it to non-status 1 BCS patients. Four hundred and forty-six patients with BCS underwent LT between 1998 and 2018, and of these 55 (12.3%) were listed as status 1. There was no difference in long-term post-liver transplant or “intention-to-treat” survival from the time of listing to death or the last day of follow-up between status 1 and non-status 1 groups. Graft and patient survival at 5 years for status 1 patients were 75% and 82%, respectively. Cox regression analysis showed that patients listed as status 1 (aHR: 0.45, p < .02) were associated with a better survival. BCS patients listed as status 1 have excellent survival following emergency LT.  相似文献   
95.
The parallel emergence of uterus transplantation (UTx) and other transplantation innovations including face and hand transplantation led to the categorization of the uterus as a vascular composite allograft (VCA). With >60 transplants and >20 births worldwide, UTx is transitioning rapidly from a research endeavor to an effective treatment option for women with uterine factor infertility. While it originally made sense to group the innovations under one umbrella, it is time to revisit the designation of UTx as a VCA. We describe how UTx needs unique policy, procedural codes, insurance contracts, and educational initiatives. We contend that separating UTx from VCAs may become necessary in the future to avoid hindering the growth and regulation of this field.  相似文献   
96.
COVID-19 has been sweeping the globe, hitting the United States particularly hard with a state of emergency declared on March 13, 2020. Transplant hospitals have taken various precautions to protect patients from potential exposure. OPTN donor, candidate, and transplant data were analyzed from January 5, 2020 to September 5, 2020. The number of new waiting list registrations decreased, with the Northeast seeing over a 50% decrease from the week of 3/8 versus the week of 4/5. The national transplant system saw near cessation of living donor transplantation (−90%) from the week of 3/8 to the week of 4/5. Similarly, deceased donor kidney transplant volume dropped from 367 to 202 (−45%), and other organs saw similar decreases: lung (−70%), heart (−43%), and liver (−37%). Deceased donors recovered dropped from 260 to 163 (−45%) from 3/8 compared to 4/5, including a 67% decrease for lungs recovered. The magnitude of this decrease varied by geographic area, with the largest percent change (−67%) in the Northeast. Despite the pandemic, discard rates across organ has remained stable. Although the COVID-19 pandemic continues to evolve, OPTN data show recent evidence of stabilization, an indication that an early recovery of the number of living and deceased donors and transplants has ensued.  相似文献   
97.
98.
网络规模迭加法是一种在社会网络理论基础上建立的间接估计人群规模的方法,由于不需要接触目标人群,在估计隐藏人群规模时得到了广泛应用。该方法也在不断发展进步中,本文从传统的网络规模迭加法及其进展及与新的调查技术结合三个方面进行综述,旨在为该方法的进一步应用提供参考。  相似文献   
99.
BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.  相似文献   
100.
The membrane properties of the neurons located in the ventral part of the periaqueductal grey (PAG) of the guinea-pig were studied using an in vitro slice preparation. Cells had low values of resting membrane potential (-53.3 +/- 1.3 mV, mean +/- standard error), high input resistance (195. +/- 16.2 M ohm) and moderate values of membrane time constant (12.6 +/- 0.7 ms). The last two parameters changed as recordings were made along the sagittal axis, higher values corresponding to the more rostral cells. Three main neuronal types-fusiform, triangular and stellate-were found in the ventral PAG using intracellular injection of Lucifer yellow. A study of the cell number and cell density was carried out in coronal and sagittal sections of the ventral PAG. This analysis showed a clear gradient of size in this region arising from the gradual disappearance of large (17 to 40 microm) neurons in the caudorostral direction. The neuronal density also increased in this direction. Therefore, some electrotonic and morphological parameters differ along the sagittal axis. These findings suggest a larger neuronal heterogeneity of the caudal part of the PAG, and might contribute to a functional segregation of this region.  相似文献   
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