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81.
Dimitrios Moris Brian I. Shaw Cecilia Ong Ashton Connor Mariya L. Samoylova Samuel J. Kesseli Nader Abraham Jared Gloria Robin Schmitz Zachary W. Fitch Bryan M. Clary Andrew S. Barbas 《肝胆外科与营养》2021,10(3):315
BackgroundSelection of the optimal treatment modality for primary liver cancers remains complex, balancing patient condition, liver function, and extent of disease. In individuals with preserved liver function, liver resection remains the primary approach for treatment with curative intent but may be associated with significant mortality. The purpose of this study was to establish a simple scoring system based on Model for End-stage Liver Disease (MELD) and extent of resection to guide risk assessment for liver resections.MethodsThe 2005–2015 NSQIP database was queried for patients undergoing liver resection for primary liver malignancy. We first developed a model that incorporated the extent of resection (1 point for major hepatectomy) and a MELD-Na score category of low (MELD-Na =6, 1 point), medium (MELD-Na =7–10, 2 points) or high (MELD-Na >10, 3 points) with a score range of 1–4, called the Hepatic Resection Risk Score (HeRS). We tested the predictive value of this model on the dataset using logistic regression. We next developed an optimal multivariable model using backwards sequential selection of variables under logistic regression. We performed K-fold cross validation on both models. Receiver operating characteristics were plotted and the optimal sensitivity and specificity for each model were calculated to obtain positive and negative predictive values.ResultsA total of 4,510 patients were included. HeRS was associated with increased odds of 30-day mortality [HeRS =2: OR =3.23 (1.16–8.99), P=0.025; HeRS =3: OR =6.54 (2.39–17.90), P<0.001; HeRS =4: OR =13.69 (4.90–38.22), P<0.001]. The AUC for this model was 0.66. The AUC for the optimal multivariable model was higher at 0.76. Under K-fold cross validation, the positive predictive value (PPV) and negative predictive value (NPV) of these two models were similar at PPV =6.4% and NPV =97.7% for the HeRS only model and PPV =8.4% and NPV =98.1% for the optimal multivariable model.ConclusionsThe HeRS offers a simple heuristic for estimating 30-day mortality after resection of primary liver malignancy. More complicated models offer better performance but at the expense of being more difficult to integrate into clinical practice. 相似文献
82.
Kutner Bryan A. Simoni Jane M. Aunon Frances M. Creegan Emma Balán Ivan C. 《Archives of sexual behavior》2021,50(4):1651-1663
Archives of Sexual Behavior - Gay, bisexual, and other men who have sex with men (MSM) experience alarming HIV disparities alongside sub-optimal engagement in HIV interventions. Among MSM, stigma... 相似文献
83.
HEC Forum - In this paper, I consider the role of conscience in medical practice. If the conscientious practice of individual practitioners cannot be defended or is incoherent or unreasonable on... 相似文献
84.
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86.
C S Bryan 《Southern medical journal》1990,83(2):199-202
Retroviruses emerged before Homo sapiens in the course of vertebrate evolution. The first human retrovirus was isolated in 1979; the human immunodeficiency virus (HIV-1) assumed epidemic importance in 1981. That such a novel threat to the survival of our species struck only when we had in place, for the first time, the science necessary to fight back seems remarkably coincidental. Cause-and-effect explanations include (1) human activities unique to the late 20th century and (2) a merciful, slow-to-anger God willing to "hold back" until the right time (chairos). By either possibility, AIDS might signify our failure to manage properly the world's ecosystems, the limitations of scientific progress, and/or deficiencies in our collective worldview. 相似文献
87.
Bryan J 《The Health service journal》1997,107(5580):24-27
Thirty years after the world's first successful heart transplant, UK services are embroiled in a funding row. The country's eight units carried out more than 200 transplants last year, but after-care costs are rising as more people survive longer, and cardiologists fear the switch from central to regional funding will lead to cuts. Jenny Bryan looks at the past, present and future. 相似文献
88.
Bryan S Keen J Muris N Weatherburn G Buxton M 《Health policy (Amsterdam, Netherlands)》1995,33(1):31-42
Picture archiving and communication systems (PACS) are an example of the application of computer technology in the medical field. PACS automates image handling in a hospital and has the potential to transform the way radiology is currently performed. This paper focuses on the evaluation of the PACS technology, and considers the claims that have been made for PACS, how these claims might be turned into questions to be addressed by evaluation and the appropriate methods for the evaluation of PACS. A distinction is drawn between evaluation questions for which the hospital is the appropriate focus and those for which the patient is the appropriate focus. The preferred research design is different for hospital focused PACS evaluation and patient-focused evaluation of small scale PACS systems. A contemporaneous experimental comparison within hospitals is the preferred design for the patient-focused evaluation of small scale PACS systems. The patient-focused evaluation of large scale systems and the hospital-focused evaluation of all PACS systems could feasibly be conducted as contemporaneous experimental comparisons between hospitals but the large research costs implied by such a design almost certainly mean that non-contemporaneous, non-experimental comparisons within hospitals are more realistic. The current situation for the PACS technology is that it has potential, but as yet unproven, benefits and a large capital cost. Thus, the primary purpose of funding additional PACS implementations must be to add to the currently small body of evaluation evidence. 相似文献
89.
90.
Bryan S Weatherburn G Buxton M Watkins J Keen J Muris N 《Journal of health services research & policy》1999,4(4):204-209
OBJECTIVES: To establish the net costs to the hospital and the broad range of benefits associated with a hospital-wide picture archiving and communication system (PACS) that comprised digital acquisition, storage and transmission of radiological images via a hospital-wide network to 150 workstations. METHODS: 'Before and after' comparisons and time series analyses at Hammersmith Hospital (London, UK), and comparison with five other British hospitals where PACS was not being installed. The cost analysis considered implementation costs and changes in key elements of hospital running costs, including the impact of changes in the length of inpatient stays. A range of benefit measures were investigated, including image availability, avoidance of repeat imaging, avoidance of exposure to radiation, patient turn-round speed, time from examination to image availability in intensive care, avoidance of diagnostic 'errors' by casualty doctors, the additional diagnostic value of PACS-based images and clinician satisfaction. RESULTS: The annual equivalent capital cost of the PACS was 1.7 million Pounds (annual equivalent replacement cost: 0.8 million Pound). Overall, the PACS substantially increased running costs. No convincing evidence of a PACS-induced change in length of inpatient stay was found. PACS was associated with some improvements in the performance of the radiology department: improved image availability (97.7% versus 86.9%), lower repeat imaging rate (7.3% versus 9.9%) and 20% lower total radiation doses for examinations of the lateral lumbar spine. No improvements were identified in the quality of the radiology reporting service. Benefits outside radiology included shorter time from examination to image availability for routine uses in intensive care (19 versus 37 minutes), and a lower rate of diagnostic 'errors' in casualty (0.65% versus 1.51%). High levels of satisfaction with PACS were found amongst both providers and clinical users. CONCLUSIONS: PACS was almost universally preferred by users and brought many operational and clinical benefits. However, these advantages came at a significant capital and net running cost. 相似文献