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Modeling Individual Patient Count/Rate Data over Time with Applications to Cancer Pain Flares and Cancer Pain Medication Usage

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Open journal of Statistics 2021年第5期11卷 633-654页

作者： george j. Knafl Salimah H. Meghani School of Nursing University of North Carolina at Chapel Hill Chapel Hill NC USA Department of Biobehavioral Health Sciences School of Nursing University of Pennsylvania Philadelphia PA USA

The purpose of this article is to investigate approaches for modeling individual patient count/rate data over time accounting for temporal correlation and non-constant dispersions while requiring reasonable amounts of time to search over alternative models for those data. This research addresses formulations for two approaches for extending generalized estimating equations (GEE) modeling. These approaches use a likelihood-like function based on the multivariate normal density. The first approach augments standard GEE equations to include equations for estimation of dispersion parameters. The second approach is based on estimating equations determined by partial derivatives of the likelihood-like function with respect to all model parameters and so extends linear mixed modeling. Three correlation structures are considered including independent, exchangeable, and spatial autoregressive of order 1 correlations. The likelihood-like function is used to formulate a likelihood-like cross-validation (LCV) score for use in evaluating models. Example analyses are presented using these two modeling approaches applied to three data sets of counts/rates over time for individual cancer patients including pain flares per day, as needed pain medications taken per day, and around the clock pain medications taken per day per dose. Means and dispersions are modeled as possibly nonlinear functions of time using adaptive regression modeling methods to search through alternative models compared using LCV scores. The results of these analyses demonstrate that extended linear mixed modeling is preferable for modeling individual patient count/rate data over time, because in example analyses, it either generates better LCV scores or more parsim

关键词： Adaptive Regression Extended Linear Mixed Modeling Generalized Estimating Equations Likelihood-Like Cross-Validation Poisson Regression

Metabolic Plasticity of Nitrogen Assimilation by Porphyra umbilicalis(Linnaeus) Kützing

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journal of Ocean University of China 2012年第4期11卷 517-526页

作者： jang K.Kim george P.Kraemer Charles Yarish Departments of Ecology and Evolutionary Biology and Marine Sciences University of Connecticut1 University PlaceStamfordCT 06901USA Department of Environmental Studies Purchase College735 Anderson Hill RoadPurchaseNY 10577USA

The physical stresses associated with emersion have long been considered major factors determining the vertical zona- tion of intertidal seaweeds. We examined Porphyra umbilicalis （Linnaeus） Kiitzing thalli from the vertical extremes in elevation of an intertidal population （i.e. upper and lower intertidal zones） to determine whether Porphyra thalli acclimate to different vertical elevations on the shore with different patterns of nitrate uptake and nitrate reductase （NR） and glutamine synthetase （GS） activities in response to different degrees of emersion stress. We found that the nitrate uptake and NR recovery in the emersed tissues took longer in lower intertidal sub-population than in upper intertidal sub-population; and GS activity was also significantly affected by emersion and, interestingly, such an activity was enhanced by emersion of thalli from both upper and lower intertidal zones. These results sug- gested that intta-population variability in post-emersion recovery of physiological functions such as nutrient uptake and NR activity enables local adaptation and contributes to the wide vertical distribution ofP. umbilicalis. The high GS activity during periodic emer- sion stress may be a protective mechanism enabling P umbilicalis to assimilate nitrogen quickly when it again becomes available, and may also be an evidence ofphotorespiration during emersion.

关键词： emersion glutamine synthetase nitrate reductase nitrogen assimilation Porphyra

Regression Modeling of Individual-Patient Correlated Discrete Outcomes with Applications to Cancer Pain Ratings

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Open journal of Statistics 2022年第4期12卷 456-485页

作者： george j. Knafl Salimah H. Meghani School of Nursing University of North Carolina at Chapel Hill Chapel Hill USA Department of Biobehavioral Health Sciences School of Nursing University of Pennsylvania Philadelphia USA

Purpose: To formulate and demonstrate methods for regression modeling of probabilities and dispersions for individual-patient longitudinal outcomes taking on discrete numeric values. Methods: Three alternatives for modeling of outcome probabilities are considered. Multinomial probabilities are based on different intercepts and slopes for probabilities of different outcome values. Ordinal probabilities are based on different intercepts and the same slope for probabilities of different outcome values. Censored Poisson probabilities are based on the same intercept and slope for probabilities of different outcome values. Parameters are estimated with extended linear mixed modeling maximizing a likelihood-like function based on the multivariate normal density that accounts for within-patient correlation. Formulas are provided for gradient vectors and Hessian matrices for estimating model parameters. The likelihood-like function is also used to compute cross-validation scores for alternative models and to control an adaptive modeling process for identifying possibly nonlinear functional relationships in predictors for probabilities and dispersions. Example analyses are provided of daily pain ratings for a cancer patient over a period of 97 days. Results: The censored Poisson approach is preferable for modeling these data, and presumably other data sets of this kind, because it generates a competitive model with fewer parameters in less time than the other two approaches. The generated probabilities for this model are distinctly nonlinear in time while the dispersions are distinctly nonconstant over time, demonstrating the need for adaptive modeling of such data. The analyses also address the dependence of these daily pain ratings on time and the daily numbers of pain flares. Probabilities and dispersions change differently over time for different numbers of pain flares. Conclusions: Adaptive modeling of daily pain ratings for individual cancer patients is an effective way

关键词： Cancer Pain Ratings Discrete Regression Extended Linear Mixed Modeling Likelihood-Like Cross-Validation Nonlinear Moderation

Dendritic cells in hepatitis C virus infection:Key players in the IFNL3-genotype response

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World journal of Gastroenterology 2014年第47期20卷 17830-17838页

作者： Kate S O'Connor jacob george David Booth Golo Ahlenstiel Institute for Immunology and Allergy Research Westmead Millennium InstituteUniversity of SydneySydneyNSW 2145Australia Storr Liver Unit Westmead Millennium Institute and Westmead HospitalUniversity of SydneySydneyNSW 2145Australia

Recently,single nucleotide polymorphisms,in the vicinity of the interferon lambda 3(IFNL3)gene have been identified as the strongest predictor of spontaneous and treatment induced clearance of hepatitis C virus(HCV)*** then,increasing evidence has implicated the innate immune response in mediating the IFNL3 genotype *** cells(DCs)are key to the host immune response in HCV infection and their vital role in the IFNL3 genotype effect is *** have identified subclasses of DCs,particularly myeloid DC2s and potentially plasmacytoid DCs as the major producers of IFNL3 in the setting of HCV *** the complexities of dendritic cell biology and the conflicting current available data,this review aims to summarize what is currently known regarding the role of dendritic cells in HCV infection and to placeit into context of what is know about lambda interferons and dendritic cells in general.

关键词： Hepatitis C virus Interferon lambda 3 Dendritic cells Plasmacytoid dendritic cells Myeloid dendritic cells Innate immunity

Atrial fibrillation in the elderly: Is ablation ready for prime time ?

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journal of Geriatric Cardiology 2005年第2期2卷 101-102页

作者： Allen j. Solomon george Washington University Hospital

Atrial fibrillation is the most common sustained arrhythmia and results in significant morbidity, especially in the elderly. The prevalence of atrial fibrillation increases dramatically with advancing age to almost 6% in individuals older than 65 years. In fact, 84% of people with atrial fibrillation are over 65 years of age.1 Additionally, the risk of stroke increases with advancing age, such that one-third of strokes in patients over the age of 65 are caused by atrial fibrillation.

关键词： Is ablation ready for prime time Atrial fibrillation in the elderly

Octreotide induces caspase activation and apoptosis in human hepatoma HepG2 cells

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World journal of Gastroenterology 2011年第3期17卷 313-321页

作者： Nikos j Tsagarakis Ioannis Drygiannakis Antonis G Batistakis george Kolios Elias A Kouroumalis Liver Research Laboratory School of MedicineUniversity of Crete Laboratory of Pharmacology School of MedicineDemocritus University of Thrace Department of Gastroenterology and Hepatology University Hospital of Heraklion

AIM: To investigate the role of octreotide on cellular proliferation and apoptosis of human hepatoma (HepG2) cells. METHODS: We studied cellular proliferation, apoptosis and the possible internal caspase-mediated apoptosis pathway involved, after treatment of HepG2 carcinoma cells with octreotide in comparison with the apoptosis caused by tumor necrosis factor-α (TNF-α). Activities of caspase-3, caspase-9, caspase-8 and caspase-2 were studied, while apoptosis was investigated through detection of DNA fragmentation and through identification of apoptotic cells with the annexin-V/propidium iodide flow cytometric method. RESULTS: After an initial increase in HepG2 cellular proliferation, a significant inhibition was observed with 10-8 mol/L octreotide, while TNF-α dose-dependently decreased proliferation. Early and late apoptosis was significantly increased with both substances. Octreotide significantly increased caspase-3, caspase-8 and caspase-2 activity. TNF-α signifi cantly increased only caspase-2. Cellular proliferation was decreased after treatment with octreotide or TNF-α alone but, in contrast to TNF-α, octreotide decreased proliferation only at concentrations of 10-8 mol/L, while lower concentrations increased proliferation. CONCLUSION: Our findings are suggestive of caspasemediated signaling pathways of octreotide antitumor activity in HepG2 cells, and indicate that measurements of serum octreotide levels may be important, at least in clinical trials, to verify optimal therapeutic drug concentrations.

关键词： Octreotide Hepatocellular carcinoma Apoptosis Caspases Somatostatin

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度量中国经济：购买力平价的适当应用

经济研究 2010年第1期45卷 27-38页

作者： george j. Gilboy 钟宁桦麻省理工学院(MIT)国际事务研究中心香港科技大学金融系

本文介绍了世界银行2005年购买力平价数据,并使用这些数据将中国经济的规模、结构和发展程度与世界其他主要国家做了比较。文章讨论了购买力平价与市场汇率不同的应用之处,并指出了在衡量中国相对经济实力和影响力的研究中普遍存在的一... 详细信息

本文介绍了世界银行2005年购买力平价数据,并使用这些数据将中国经济的规模、结构和发展程度与世界其他主要国家做了比较。文章讨论了购买力平价与市场汇率不同的应用之处,并指出了在衡量中国相对经济实力和影响力的研究中普遍存在的一些对于购买力平价的误用。文章比较了世界各主要国家的实际生产力水平、生活水平、投资支出和价格水平,还构建了一个指标"机械与设备相对价格"来反映一国工业化的程度。最后,使用分部门的购买力平价数据,文章比较了中国和印度2005年在各个部门上的支出总量与部门产品价格,讨论了购买力平价在分析两国相对发展程度与比较优势中的价值与局限。

关键词：购买力平价世界银行国际比较项目中国经济

The Longibrachiatum Clade of Trichoderma:a revision with new species

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Fungal Diversity 2012年第4期55卷 77-108页

作者： Gary j.Samuels Adnan Ismaiel Temesgen B.Mulaw george Szakacs Irina S.Druzhinina Christian P.Kubicek Walter M.jaklitsch United States Department of Agriculture Agricultural Research ServiceSystematic Mycology&Microbiology LaboratoryB-010a10300 Baltimore AveBeltsvilleMD 20705USA Center for Environmental Science Institute of Marine and Environmental TechnologyUniversity of MarylandBaltimoreMD 21201USA Department of Applied Biotechnology and Food Science Budapest University of Technology and Economics(BUTE)1111 BudapestGellért ter 4Hungary Vienna University of Technology Institute of Chemical EngineeringGetreidemarkt 9/1661060 WienAustria Department of Systematic and Evolutionary Botany Faculty Centre of BiodiversityUniversity of ViennaRennweg 141030 ViennaAustria

The Longibrachiatum Clade of Trichoderma is *** new species are described(***,***,***,***,***,***,***,***).The twenty-one species known to belong to the Longibrachiatum Clade are included in a synoptic *** parareesei and *** are redescribed based on new collections or additional *** teleomorphs are reported for *** and *** described species are annotated.

关键词： Hypocrea Hypocreaceae Hypocreales Endophyte Medical mycology Revision Systematics Taxonomy Soil fungi Biogeography

Thoracotomy in the emergency department for resuscitation of the mortally injured

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Chinese journal of Traumatology 2017年第3期20卷 141-146页

作者： j. Christopher DiGiacomo L.D. george Angus Long Island Comprehensive Trauma Center Department of Surgery Nassau University Medical Center. East Meadow NY 11554 USA

Purpose： Emergency department resuscitative thoracotomy is an intervention of last resort for the acutely dying victim of trauma. In light of improvements in pre-hospital emergency systems, improved operative strategies for survival such as damage control and improvements in critical care medicine, the most extreme of resuscitation efforts should be re-evaluated for the potential survivor, with success properly defined as the return of vital signs which allow transport of the patient to the operating room. Methods： A retrospective review of all patients at a suburban level I trauma center who underwent emergency department resuscitative thoracotomy as an adjunct to the resuscitation efforts normally delivered in the trauma receiving area over a 22 year period was performed. Survival of emergency department resuscitative thoracotomy was defined as restoration of vital signs and transport out of the trauma resuscitation area to the operating room. Results： Sixty-eight patients were identified, of whom 27 survived the emergency department resusci- tative thoracotomy and were transported to the operating room. Review of pre-hospital and initial hospital data between these potential long term survivors and those who died in the emergency department failed to demonstrate trends which were predictive of survival of emergency department resuscitative thoracotomy. The only subgroup which failed to respond to emergency department resuscitative thoracotomy was patients without signs of life at the scene who arrived to the treatment facility without signs of life. Conclusion： The patient population of the ＂potential survivor＂ has been expanded due to advances in critical care practices, technology, and surgical technique and every opportunity for survival should be provided at the outset. Emergency department resuscitative thoracotomy is warranted for any patient with thoracic or subdiaphragmatic trauma who presents in extremis with a history of signs of life at the scene or or

关键词： Emergencies Thoracotomy Injuries Resuscitation