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High-grade pancreatic intraepithelial lesions： prevalence and implications in pancreatic neoplasia

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Hepatobiliary & Pancreatic Diseases International 2017年第2期16卷 202-208页

作者： Jean R Park Feng Li Veeral m Oza Brett C Sklaw kevin m Cronley michael Wellner Benjamin Swanson Somashekar G Krishna Division of Hospital medicine The Ohio State University Wexner Medical Center Columbus Ohio USA Division of Gastroenterology Hepatology and Nutrition The Ohio State University Wexner Medical Center Columbus Ohio USA Department of Pathology The Ohio State University Wexner Medical Center Columbus Ohio USA

BACKGROUND： High-grade pancreatic intraepithelial neoplasia（Pan IN-3）, a precursor of pancreatic ductal adenocarcinoma（PDAC）, is not universally detected in resected pancreatic neoplasms. We sought to determine the prevalence and prognostic relevance of Pan IN-3 lesions in primary surgical resections of PDACs and intraductal papillary mucinous neoplasms（IPmNs）.mETHODS： A retrospective review of a tertiary care center pathology database（1/2000-6/2014） was performed. Demographics, imaging, pathology, disease-recurrence, and survival data were ***： A total of 458 patients who underwent primary pancreatic resection were included. “Pan IN-3” lesions were found in 74（16.2%） patients who either had PDAC（n=67） or main duct（mD）-IPmN（n=7）. Among IPmN-mDs, Pan IN-3 lesions were exclusively found in those with pathological evidence of chronic pancreatitis. For PDACs, the median overall survival（OS） for pancreata with Pan IN-3 lesions was significantly better than those without（OS 1.12 years, interquartile range [IQR] 0.72, 2.05 years vs OS 0.86 years, IQR 0.64,1.60 years respectively; P=0.04）. multivariate Cox regression analysis demonstrated that the presence of Pan IN-3 lesions was associated with a reduced risk of death（HR=0.43; 95% CI： 0.23-0.82; P=0.01）.CONCLUSIONS： Following primary resection of pancreatic adenocarcinoma, the lower survival observed in patients without Pan IN-3 lesions might suggest a state of complete or accelerated transformation. Further investigations are necessary to validate these findings that might impact disease prognosis and management.

关键词： pancreatic intraepithelial neoplasia intraductal papillary mucinous neoplasms pancreatic neoplasia pancreatic ductal adenocarcinoma

Influence of 3d transition-metal substitution on the oxygen reduction reaction electrocatalysis of ternary nitrides in acid

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Nano Research 2019年第9期12卷 2307-2312页

作者： kevin E. Fritz Yichen Yan Jin Suntivich Department of material Science and Engineering Cornell UniversityIthacaNew York 14850USA Kavli Institute at Cornell for Nanoscale Science IthacaNew York 14850USA

The development of non-precious,acid-stable,oxygen reduction reaction(ORR)electrocatalysts can significantly aid the commercialization of proton exchange membrane fuel cells(PEmFCs).We report a survey of the ORR electrocatalysis on 3d metal substituted(m=mn,Fe,Co)molybdenum and tungsten nitrides in acidic *** find that molybdate catalysts are more active than tungstates,with the specific activity depending on the chemistry of the substituted 3d *** both families,more electronegative 3d metals led to higher ORR activity(i.e.,Co>Fe>mn).We attribute this result to the ability of the more electro negative 3d metal to withdraw electro ns from the mo-or W-based active sites,effectively oxidizing the metal centers of the *** on our observation,future nitride ORR electrocatalysts can be further optimized by oxidizing the mo sites further by,for example,addi ng eve n more electro negative dopa nt metals or in corporati ng anion vaca ncies.

关键词： nitrides electrocatalysis fuel cells oxygen reduction

Environment-dependent attack rates of cryptic and aposematic butterflies

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Current Zoology 2018年第5期64卷 663-669页

作者： Brett m. SEYmOURE Andrew RAYmUNDO kevin J. mCGRAW W. OWEN mCmILLAN Ronald L, RUTOWSKI Department of Biology Colorado State University Fort Collins CO 80523 USA School of Life Sciences Arizona State University Tempe AZ 85287 USA Smithsonian Tropical Research Institute Panama City Panama

many organisms have evolved adaptive coloration that reduces their risk of predation. Cryptic colo- ration reduces the likelihood of detection/recognition by potential predators, while warning or aposematic coloration advertises unprofitability and thereby reduces the likelihood of attack. Although some studies show that aposematic coloration functions better at decreasing attack rate than crypsis, recent work has suggested and demonstrated that crypsis and aposematism are both successful strategies for avoiding predation. Furthermore, the visual environment （e.g., ambient lighting, background） affects the ability for predators to detect prey. We investigated these 2 related hypoth- eses using 2 well-known visually aposematic species of Heliconius butterflies, which occupy differ- ent habitats （open-canopy vs. closed-canopy）, and one palatable, cryptic, generalist species Junonia coenia. We tested if the differently colored butterflies differ in attack rates by placing plasti- cine models of each of the 3 species in 2 different tropical habitats where the butterflies naturally occur： disturbed, open-canopy habitat and forested, closed-canopy habitat. The cryptic model had fewer attacks than one of the aposematic models. Predation rates differed between the 2 habitats, with the open habitat having much higher predation. However, we did not find an interaction between species and habitat type, which is perplexing due to the different aposematic phenotypes naturally occurring in different habitats. Our findings suggest that during the Panamanian dry sea- son avian predation on perched butterflies is not a leading cause in habitat segregation between the 2 aposematic species and demonstrate that cryptically colored animals at rest may be better than aposematic prey at avoiding avian attacks in certain environments.

关键词： avian attacks camouflage Heliconius Junonia light environment plasticine models predation warning coloration.

Sodium and water perturbations in patients who had an acute stroke:clinical relevance and management strategies for the neurologist

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Stroke & Vascular Neurology 2022年第3期7卷 258-266页

作者： kevin C J Yuen Valerie Sharf Elizabeth Smith minhwan Kim Alissya S m Yuen Paul R macDonald Departments of Neuroendocrinology and Neurosurgery Barrow Neurological InstitutePhoenixArizonaUSA University of Arizona College of medicine and Creighton School of medicine PhoenixArizonaUSA Department of Neurology Barrow Neurological InstitutePhoenixArizonaUSA midwestern University GlendaleIllinoisUSA Creighton University School of medicine PhoenixArizonaUSA University of California Davis DavisCaliforniaUSA

Sodium and water perturbations,manifesting as hyponatraemia and hypernatraemia,are common in patients who had an acute stroke,and are associated with worse outcomes and increased *** non-stroke related causes of sodium and water perturbations in these patients include underlying comorbidities and concomitant ***,hospitalised patients who had an acute stroke may receive excessive intravenous hypotonic solutions,have poor fluid intake due to impaired neurocognition and consciousness,may develop sepsis or are administered drugs(eg,mannitol);factors that can further alter serum sodium *** and water perturbations can also be exacerbated by the development of endocrine consequences after an acute stroke,including secondary adrenal insufficiency,syndrome of inappropriate antidiuretic hormone secretion and diabetes ***,COVID-19 infection has been reported to increase the risk of development of sodium and water perturbations that may further worsen the outcomes of patients who had an acute *** there are currently no accepted consensus guidelines on the management of sodium and water perturbations in patients who had an acute stroke,we conducted a systematic review of the literature published in English and in peer-reviewed journals between January 2000 and December 2020,according to PRISmA guidelines,to assess on the current knowledge and clinical practices of this *** this review,we discuss the signs and symptoms of hyponatraemia and hypernatraemia,the pathogenesis of hyponatraemia and hypernatraemia,their clinical relevance,and we provide our recommendations for effective treatment strategies for the neurologist in the management of sodium and water perturbations in commonly encountered aetiologies of patients who had an acute stroke.

关键词： patients impaired consequences

Intravitreal stem cell paracrine properties as a potential neuroprotective therapy for retinal photoreceptor neurodegenerative diseases

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Neural Regeneration Research 2020年第9期15卷 1631-1638页

作者： kevin Puertas-Neyra Ricardo Usategui-martín Rosa mCoco Ivan Fernandez-Bueno Instituto Universitario de Oftalmobiologia Aplicada Universidad de ValladolidValladolidSpain Centro en Red de medicina Regenerativa y Terapia Celular de Castilla y Leon ValladolidSpain Red Tematica de Investigacion Cooperativa en Salud OftaredInstituto de Salud CarlosⅢValladolidSpain

Retinal degenerations are the leading causes of irreversible visual loss worldwide. many pathologies included under this umbrella involve progressive degeneration and ultimate loss of the photoreceptor cells, with age-related macular degeneration and inherited and ischemic retinal diseases the most relevant. These diseases greatly impact patients' daily lives, with accompanying marked social and economic consequences. However, the currently available treatments only delay the onset or slow progression of visual impairment, and there are no cures for these photoreceptor diseases. Therefore, new therapeutic strategies are being investigated, such as gene therapy, optogenetics, cell replacement, or cell-based neuroprotection. Specifically, stem cells can secrete neurotrophic, immunomodulatory, and anti-angiogenic factors that potentially protect and preserve retinal cells from neurodegeneration. Further, neuroprotection can be used in different types of retinal degenerative diseases and at different disease stages, unlike other potential therapies. This review summarizes stem cell-based paracrine neuroprotective strategies for photoreceptor degeneration, which are under study in clinical trials, and the latest preclinical studies. Effective retinal neuroprotection could be the next frontier in photoreceptor diseases, and the development of novel neuroprotective strategies will address the unmet therapeutic needs.

关键词： clinical trials growth factors intraocular injection intravitreal injection neuroprotection paracrine properties photoreceptors preclinical models retinal diseases stem cells

Fabrication of Noble metal-semiconductor hybrid nanostructures using phase transfer

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Nano Research 2013年第2期6卷 121-130页

作者： Tanushree Bala Ajay Singh Ambarish Sanyal Catriona O'Sullivan Fathima Laffir Claudia Coughlan kevin m. Ryan materials and Surface Science Institute and Department of Chemical and Environmental Sciences University of Limerick Limerick Ireland SFI-Strategic Research Cluster in Solar Energy Research University of Limerick Ireland

An easy and effective solution based procedure for the synthesis of noble metal （both Au and Ag） tipped semiconductor nanomaterials is demonstrated where the metal precursors are taken in water and the semiconductors in organic medium, exploiting the phase transfer and reducing capability of suitably chosen ligands. The phase tranfer route is a generalised approach to form either Ag or Au tips on cadmium chalcogenide nanoparticles and nanorods. While multiple dots of noble metals are formed on the semiconductor nanomaterials initiall~ these coalesce into larger islands with time. The hybrids are characterized by transmission electron microscopy （TEm）, X-ray diffraction （XRD）, photoluminescence （PL）, ultraviolet-visible spectroscopy （UV-vis） and X-ray photoelectron spectroscopy （XPS）. A detailed FTIR analysis was also carried out to delineate the role of the ligands in the synthesis.

关键词： semiconductor-metalhybrids Ag tips Au tips phase transfer

Chicken-Footed Gods or Village Protectors： Conscription, Community, and Conflict in Rural Sichuan, 1937-1945

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Frontiers of History in China 2014年第1期9卷 56-82页

作者： kevin Landdeck Sarah Lawrence Coliege Bronxville NY 10708 USA

mobilizing men to serve in the army was one of the fundamental tasks of the Nationalist government during the Anti-Japanese War （1937-45）. Using ground-level conscription cases from counties around Chongqing, this paper examines wartime rural administration. In interior areas, the draft rested on rural administrators, the recently revived baojia system. The baofia heads were in a difficult position： the state demanded full quotas of draftees, while residents tried to leverage bureaucratic discipline by filing accusations against them with higher ups. Their divided loyalties produced both predation and protection. Alongside the familiar stories of predatory extortion and press-gang conscription, baojia leaders also acted in ways that were protective of their neighbours and communities. The patterns of draft-related cases in rural Sichuan revise our picture of baojia leaders as unchecked bullies and thus throw new light on both the KmT＇s war effort and its state-making.

关键词： Anti-Japanese War (1937m5) conscription KmT Sichuan baojia,rural society state-making

Is there an anatomical endophenotype for neurodevelopmental disorders? A review of dual disorder anatomical likelihood estimation (ALE) meta-analyses of grey matter volumes

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Chinese Science Bulletin 2011年第32期56卷 3376-3381页

作者： mCALONAN Grainne m YU kevin K CHAN Raymond C K CHUA Siew E CHEUNG Charlton Department of Psychiatry the University of Hong Kong State Key Laboratory for Brain and Cognitive Sciences the University of Hong Kong Neuropsychology and Applied Cognitive Neuroscience Laboratory Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences

The term "neurodevelopmental disorder" broadly encompasses conditions thought to arise early in development and includes schizophrenia, bipolar disorder and autism among others. These conditions share a number of genetic and environmental risk factors postulated to lead to common difficulties in socio-emotional processing, communication and cognitive function. The alternative position is that, while the same traits are affected across these conditions, the nature or direction in which they are modified may be distinct. mRI studies provide a rapidly expanding and rich database which we propose can be used to contribute to this debate. Anatomical likelihood estimation (ALE) is a method of meta-analysis applied to voxel-based mRI studies. We have adapted this method to explore the extent to which schizophrenia and bipolar disorder and schizophrenia and autism share a common brain structural phenotype. We will review this work here and discuss whether there is sufficient other evidence to justify a common framework for further research into the inter-relatedness of such conditions.

关键词：神经疾病似然估计审查工作解剖精神分裂症稳定质数进修

Standard method design considerations for semi-quantification of total naphthenic acids in oil sands process affected water by mass spectrometry： A review

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 497-507页

作者： kevin A. Kovalchik matthew S. macLennan Kerry m. Peru John V. Headley David D.Y. Chen Department of Chemistry University of British Columbia Vancouver BC V6T 1Z1 Canada Watershed Hydrology and Ecology Research Division Water Science and Technology Directorate Science and Technology Branch Environment and Climate Change Canada Saskatoon SK S7N 3H5 Canada

Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytical methods have been developed for the semiquantification of total naphthenic acids in water samples. However, different methods can give different results, prompting investigation into the comparability of the many methods. A review of important methodological features for analyzing total naphthenic acids is presented and informs the design of future standard methods for the semi- quantification of total naphthenic acids using mass spectrometry. The design considerations presented are a synthesis of discussions from an Environment and Climate Change Canada （ECCC） led taskforce of 10 laboratory experts from government, industry and academia during April 2016 and subsequent discussions between University of British Columbia and ECCC representatives. matters considered are： extraction method, solvent, pH, and temperature; analysis instrumentation and resolution; choice of calibration standards; use of surrogate and internal standards; and use of online or offline separation prior to analysis. The design considerations are amenable to both time-of-flight and Orbitrap mass spectrometers.

关键词： total naphthenic acids environmental samples oil sands process affected water polar organics mass spectrometry