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排序方式: 共有1711条查询结果,搜索用时 15 毫秒
31.
Lilian Minne Tudor Toma Evert de Jonge Ameen Abu-Hanna 《Artificial intelligence in medicine》2013,57(2):111-117
ObjectiveRecently, we devised a method to develop prognostic models incorporating patterns of sequential organ failure to predict the eventual hospital mortality at each day of intensive care unit (ICU) stay. In this study, we investigate using a real world setting how these models perform compared to physicians, who are exposed to additional information than the models.MethodsWe developed prognostic models for days 2–7 of ICU stay by data-driven discovery of patterns of sequential qualitative organ failure (SOFA) scores and embedding the patterns as binary variables in three types of logistic regression models. Type A models include the severity of illness score at admission (SAPS-II) and the SOFA patterns. Type B models add to these covariates the mean, max and delta (increments) of SOFA scores. Type C models include, in addition, the mean, max and delta in expert opinion (i.e. the physicians’ prediction of mortality).ResultsPhysicians had a statistically significantly better discriminative ability compared to the models without subjective information (AUC range over days: 0.78–0.79 vs. 0.71–0.74) and comparable accuracy (Brier score range: 0.15–0.18 vs. 0.16–0.18). However when we combined both sources of predictions, in Type C models, we arrived at a significantly superior discrimination as well as accuracy than the objective and subjective models alone (AUC range: 0.80–0.83; Brier score range: 0.13–0.16).ConclusionThe models and the physicians draw on complementary information that can be best harnessed by combining both prediction sources. Extensive external validation and impact studies are imperative to further investigate the ability of the combined model. 相似文献
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33.
Characterization of skin blister fluids from children with Epstein–Barr virus‐associated lymphoproliferative disease 下载免费PDF全文
Taizo Wada Tomoko Toma Hanae Miyazawa Eiko Koizumi Tetsujiro Shirahashi Yusuke Matsuda Akihiro Yachie 《The Journal of dermatology》2018,45(4):444-449
Epstein–Barr virus (EBV)‐associated T‐ or natural killer (NK)‐cell lymphoproliferative disease (LPD) is a heterogeneous group of disorders characterized by chronic proliferation of EBV‐infected lymphocytes. Patients may present with severe skin manifestations, including hypersensitivity to mosquito bites (HMB) and hydroa vacciniforme (HV)‐like eruption, which are characterized by blister formation and necrotic ulceration. Skin biopsy specimens show inflammatory reactions comprising EBV‐infected lymphocytes. However, blister fluids have not been fully assessed in patients with this disease. Blister fluids were collected from three patients with EBV‐associated LPD: two with HMB and one with HV. Immunophenotyping of blister lymphocytes and measurement of tumor necrosis factor (TNF)‐α in blister fluids were performed. The patients with HMB and HV exhibited markedly increased percentages of NK and γδ T cells, respectively, in both peripheral blood and blister fluids. These NK and γδ T cells strongly expressed the activation marker human leukocyte antigen‐DR and were considered to be cellular targets of EBV infections. TNF‐α was highly elevated in all blister fluids. Severe local skin reactions of EBV‐associated LPD may be associated with infiltrating EBV‐infected lymphocytes and a high TNF‐α concentration in blister fluids. 相似文献
34.
Pashtoon Murtaza Kasi Faisal Shahjehan Jordan J. Cochuyt Zhuo Li Dorin Toma Colibaseanu Amit Merchea 《Clinical colorectal cancer》2019,18(1):e87-e95
Background
Recent trends have identified increasing number of young individuals with rectal and colon cancers. These individuals, who are younger than 50 years old, in most instances would not meet screening guidelines. We aimed to report the characteristics and trend of the rising proportion of young individuals being diagnosed with rectal and colon cancers at our institutions.Patients and Methods
This study included 3381 rectal and colon cancer patients from the Mayo Clinic cancer registry from 1972 to 2017 who were diagnosed with rectal or colon cancer and who were < 50 years old. Patient and cancer characteristics are described. The Cochran-Armitage trend test was used to see if the change in percentage diagnosed at age < 50 years had a significant trend over the years. A linear regression model was fit to estimate the percentage change per year when the trend was approximately linear.Results
The percentage of patients diagnosed with rectal or colon cancer in different age categories over the years showed a rising trend for individuals aged < 50. Most of these tumors were distal (rectum, left-sided colon, and right-sided colon were 49.8%, 28.8%, and 21.4%, respectively). This was more so for patients < 50 diagnosed with rectal cancer, which showed a linear increase at a rate of 0.26% per year (P < .001).Conclusion
Our study affirms the rising proportion of colorectal cancers found in young individuals, with a linear ongoing rise of rectal cancers in particular. This may have implications for the current screening recommendations for colorectal cancers, which are already being revised. 相似文献35.
Epilepsy is known as one of the most frequent neurological diseases, characterized by an enduring
predisposition to generate epileptic seizures. Oxidative stress is believed to directly participate in pathways
leading to neurodegeneration, which serves as the most important propagating factor, leading to the epileptic
condition and cognitive decline. Moreover, there is also a growing body of evidence showing the disturbance
of antioxidant system balance and consequently increased production of reactive species in patients with
epilepsy. A meta-analysis, conducted in the present review confirms an association between epilepsy and
increased lipid peroxidation. Furthermore, it was also shown that some of the antiepileptic drugs could potentially be
responsible for additionally increased lipid peroxidation. Therefore, it is reasonable to propose that during the epileptic
process neuroprotective treatment with antioxidants could lead to less sever structural damages, reduced epileptogenesis
and milder cognitive deterioration. To evaluate this hypothesis studies investigating the neuroprotective therapeutic
potential of various antioxidants in cells, animal seizure models and patients with epilepsy have been reviewed. Numerous
beneficial effects of antioxidants on oxidative stress markers and in some cases also neuroprotective effects were observed
in animal seizure models. However, despite these encouraging results, till now only a few antioxidants have been further
applied to patients with epilepsy as an add-on therapy. Based on the several positive findings in animal models, a strong
need for more carefully planned, randomized, double-blind, cross-over, placebo-controlled clinical trials for the evaluation
of antioxidants efficacy in patients with epilepsy is warranted. 相似文献
36.
37.
Paolo Toma 《European journal of pediatrics》2013,172(5):713-713
38.
Alessandro Alabastri Salvatore Tuccio Andrea Giugni Andrea Toma Carlo Liberale Gobind Das Francesco De Angelis Enzo Di Fabrizio Remo Proietti Zaccaria 《Materials》2013,6(11):4879-4910
In this paper, we review the principal theoretical models through which the dielectric function of metals can be described. Starting from the Drude assumptions for intraband transitions, we show how this model can be improved by including interband absorption and temperature effect in the damping coefficients. Electronic scattering processes are described and included in the dielectric function, showing their role in determining plasmon lifetime at resonance. Relationships among permittivity, electric conductivity and refractive index are examined. Finally, a temperature dependent permittivity model is presented and is employed to predict temperature and non-linear field intensity dependence on commonly used plasmonic geometries, such as nanospheres. 相似文献
39.
Marco Antonio de Andrade Belo Vando Edésio Soares Luciano Melo de Souza Márcia Ferreira da Rosa Sobreira Daniela Miyasaka Silveira Cassol Sandra Barioni Toma 《Experimental and toxicologic pathology》2012,64(3):155-165
The present study evaluated the hepatoprotective effect of an N-acetyl dl-methionine + choline chloride + caffeine + thiamine hydrochloride + nicotinamide + pyridoxine hydrochloride compound at doses of 0.2, 0.6 and 1.0 mL/kg of b.w., and the assessment was done by the investigation of serum-enzymatic activity, metabolic functions of the liver and histophatological changes in female Wistar rats, which were subjected to experimental intoxication with CCl4. One hundred and nineteen rats were randomly distributed into 17 groups, performing five different treatments, being evaluated seven animals per treatment in four periods: 2, 4, 6 and 8 days after CCl4-induced intoxication. Treated rats with the hepatoprotective medicine (HM) presented a significant reduction in infiltration of inflammatory cells, steatosis, necrosis and liver congestion when compared to non-treated rats (control). Beside these results, the treatment showed a positive effect on circulatory alterations in the intoxicated animals, with reduction of spleen and renal congestion, as well as, promotion of a significant improvement in ALT, AST, LDH, ALP, GGT enzymatic serum activity reduction and in recovering liver function regarding the metabolism of urea, triglycerides and glucose. These findings indicate therapeutic usefulness of the compound when administered at dose 0.6 and 1.0 mL/kg of b.w. in female Wistar rats. 相似文献