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31.
Alex John London 《The Hastings Center report》2019,49(1):15-21
Although decision‐making algorithms are not new to medicine, the availability of vast stores of medical data, gains in computing power, and breakthroughs in machine learning are accelerating the pace of their development, expanding the range of questions they can address, and increasing their predictive power. In many cases, however, the most powerful machine learning techniques purchase diagnostic or predictive accuracy at the expense of our ability to access “the knowledge within the machine.” Without an explanation in terms of reasons or a rationale for particular decisions in individual cases, some commentators regard ceding medical decision‐making to black box systems as contravening the profound moral responsibilities of clinicians. I argue, however, that opaque decisions are more common in medicine than critics realize. Moreover, as Aristotle noted over two millennia ago, when our knowledge of causal systems is incomplete and precarious—as it often is in medicine—the ability to explain how results are produced can be less important than the ability to produce such results and empirically verify their accuracy. 相似文献
32.
33.
Samuel G.A. Wood Nilanjan Chakraborty Martin W. Smith Mark J. Summers Stuart A. Brewer 《Journal of occupational and environmental hygiene》2019,16(1):41-53
Steady-state axisymmetric simulations using the Reynolds-Averaged Navier-Stokes equations have been carried out in order to optimize the performance of a Chemical, Biological, Radiological, and Nuclear (CBRN) canister filter for its use in a powered air-purifying respirator (PAPR). Alterations have been made to the shape of the canister, the spacing of the rear wall of the canister with regard to the carbon filter, and the bracketing between (i) the particulate filter and the carbon bed and (ii) the carbon bed and the canister wall. The pressure drops across the canister and the residence time distribution at the rear of the carbon bed have been analyzed in detail based on an extensive parametric analysis involving the aforementioned variations. It has been demonstrated that the non-uniform porosity profile of the carbon bed resulted in alternating regions of high and low velocity close to the canister wall, providing a possible route for breakthrough. Designs, which included a bracket at the rear of the carbon bed, blocked this route and consequently had a longer minimum mean residence time than those, which did not. It has also been shown that the spacing between the carbon bed and the canister rear wall had a large impact on both residence time and pressure drop. In cases where the carbon backed directly onto the canister rear wall flow in the axial direction from the outside wall toward the canister axis resulted in far greater pressure drop and a reduction in minimum mean residence time within the carbon bed. 相似文献
34.
Zumel-Marne Angela Kundi Michael Castaño-Vinyals Gemma Alguacil Juan Petridou Eleni Th Georgakis Marios K. Morales-Suárez-Varela Maria Sadetzki Siegal Piro Sara Nagrani Rajini Filippini Graziella Hutter Hans-Peter Dikshit Rajesh Woehrer Adelheid Maule Milena Weinmann Tobias Krewski Daniel ′t Mannetje Andrea Momoli Franco Lacour Brigitte Mattioli Stefano Spinelli John J. Ritvo Paul Remen Thomas Kojimahara Noriko Eng Amanda Thurston Angela Lim Hyungryul Ha Mina Yamaguchi Naohito Mohipp Charmaine Bouka Evdoxia Eastman Chelsea Vermeulen Roel Kromhout Hans Cardis Elisabeth 《Journal of neuro-oncology》2020,147(2):427-440
Journal of Neuro-Oncology - We used data from MOBI-Kids, a 14-country international collaborative case–control study of brain tumors (BTs), to study clinical characteristics of the tumors in... 相似文献
35.
Patel Mallika P. Kirkpatrick John P. Johnson Margaret O. Healy Patrick Herndon James E. Lipp Eric S. Miller Elizabeth S. Desjardins Annick Randazzo Dina Friedman Henry S. Ashley David M. Peters Katherine B. 《Journal of neuro-oncology》2020,147(2):477-483
Journal of Neuro-Oncology - Primary central nervous system lymphoma (PCNSL) is a subtype of non-Hodgkin’s lymphoma that involves the brain, spinal cord, or leptomeninges, without evidence of... 相似文献
36.
Renuka V. Iyer MD Bhavana Konda MD MPH Christos Fountzilas MD Sarbajit Mukherjee MD MS Dwight Owen MD MS Kristopher Attwood PhD Chong Wang MA Orla Maguire PhD Hans Minderman PhD Sheryl-Ann Suffren BA Karen Hicks BS John Wilton PhD Robert Bies PhD Danielle Casucci BA Diane Reidy-Lagunes MD Manisha Shah MD 《Cancer》2020,126(16):3689-3697
37.
Ki-Yong An Andria R. Morielli Dong-Woo Kang Christine M. Friedenreich Donald C. McKenzie Karen Gelmon John R. Mackey Robert D. Reid Kerry S. Courneya 《International journal of cancer. Journal international du cancer》2020,146(1):150-160
The Combined Aerobic and Resistance Exercise (CARE) Trial compared different types and doses of exercise performed during breast cancer chemotherapy. Here, we report the longer-term follow-up of patient-reported outcomes, health-related fitness and exercise behavior at 6, 12 and 24 months postintervention. A multicenter trial in Canada randomized 301 breast cancer patients initiating chemotherapy to thrice weekly, supervised exercise consisting of a standard dose of 25–30 min of aerobic exercise (STAN; n = 96), a higher dose of 50–60 min of aerobic exercise (HIGH; n = 101) or a combined dose of 50–60 min of aerobic and resistance exercise (COMB; n = 104) performed for the duration of chemotherapy (median of 17 weeks). Primary outcomes were patient-reported outcomes including quality of life, cancer-related symptoms and psychosocial outcomes. Secondary outcomes were objective health-related fitness (assessed at 12 months only) and self-reported exercise behavior. A total of 269 (89.4%) participants completed patient-reported outcomes at all three follow-up time points and 263 (87.4%) completed the health-related fitness assessment at 12-month follow-up. COMB was significantly superior to (i) STAN for sleep quality at 6-month follow-up (p = 0.027); (ii) HIGH for upper body muscular endurance at 12-month follow-up (p = 0.020); and (iii) HIGH for meeting the resistance exercise guideline at 6-month follow-up (p = 0.006). Moreover, self-reported meeting of the combined exercise guideline during follow-up was significantly associated with better patient-reported outcomes and health-related fitness. Performing combined exercise during and after breast cancer chemotherapy may result in better longer-term patient-reported outcomes and health-related fitness compared to performing aerobic exercise alone. 相似文献
38.
Background
Though the optimal treatment regimen in older patients with glioblastoma multiforme (GBM) remains to be established, multiple randomized studies have supported the use of hypofractionated (1–3?weeks) versus traditional regimens (6?weeks). Here we examine hypofractionated regimen practice patterns among older patients with GBM.Methods
We used the National Cancer Database and included individuals aged ≥65?years with GBM diagnosed from 2005 to 2014 undergoing biopsy/resection followed by chemotherapy and radiation initiated ≤8-weeks of diagnosis. We defined traditional fractionation as ≤200?cGy and hypofractionation as >200?cGy. We compared patient characteristics using a chi-squared test and multivariable logistic regression. We compared 90-day mortality rates following initiation of radiation using the Wald statistic in propensity score matched cohorts.Results
The final cohort included 14,931 individuals with 1524 undergoing hypofractionated treatment. From 2005 to 2014 hypofractionated utilization rates were 7%, 9%, 13%, and 18% among those 65–69, 70–74, 75–79, and ≥80?years of age, respectively. Patients treated at an academic/research center had a >60% increased odds (OR, 1.61; 95% CI, 1.43–1.81) of undergoing hypofractionated regimens versus a community center. Ninety-day mortality rates were high in both groups (hypofractionated: 32%; traditional: 24%; p?<?.001).Conclusions
The majority of older GBM patients do not undergo hypofractionated radiation. High 90-day mortality in both groups suggests that hypofractionation may improve the survival-to-treatment time ratio and positively impact patient quality of life. Hypofractionated radiation regimens for GBM should be discussed with older patients and considered for inclusion in efforts to improve the quality and value of cancer care. 相似文献39.
40.
Stephanie A. Grilo Marina Catallozzi John S. Santelli Hanying Yan Xiaoyu Song Jennifer Heitel Kristen Kaseeska Julie Gorzkowski Alexandra E. Dereix Jonathan D. Klein 《The Journal of adolescent health》2019,64(3):311-318