检索结果-南通市图书馆

World Journal of Gastroenterology 2007年第39期13卷 5282-5284页

作者： eric Ibegbu Manish Relan kenneth J Vega Divisions of Gastroenterology and General Internal Medicine University of Florida Health Science Center/Jacksonville Jacksonville FL32207 United States

Percutaneous endoscopic gastrostomy (PeG) tube complications can be serious or life threatening. Retrograde intussusception is a very rare complication of PeG tubes with only 9 cases reported in the literature. We describe a case of retrograde intussusception, associated with the use of a Foley catheter as a replacement gastrostomy tube, presenting with upper gastrointestinal bleeding. To our knowledge, this is the first reported case of PeG-related retrograde intussusception successfully managed in a non-surgical manner. Retrograde intussusception likely occurred due to migration of the replacement tube with resultant securing and invagination of the proximal jejunum when the gastrostomy tube was anchored to the abdominal wall.

关键词： Percutaneous endoscopic gastrostomy Intussusception Migration and upper gastrointestinal bleeding

Annual survival and site fidelity of free-ranging white-tailed deer (Odocoileus virginianus): comparative demography before (1983- 1992) and after (1993-2005) spatial confinement

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Integrative Zoology 2014年第1期9卷 24-33页

作者： Stephen L.WeBB kenneth L.Gee The Samuel Roberts Noble Foundation ArdmoreOklahoma USA

Survival and movement are important demographic variables influencing the dynamics of large herbivores with implications for management and evolution of life-history *** practices such as spatial con-finement and harvest regulation attempt to control survival and movement for the sustainability of harvested deer populations,but a paucity of long-term data exists on these management *** examined annual survival and site fidelity of free-ranging white-tailed deer(Odocoileus virginianus)over 10 years(1983-1992)to compare demographic parameters after spatial confinement(1993-2005).We used capture records(n=174;104 females,70 males),marked deer recaptures(n=42),and dead recoveries(n=68)to estimate sex-specif-ic,age-specific and time-specific *** found that annual female survival was 50%from 1983-1987 during a period of intense harvest,but increased to 93.7%after intense harvesting was *** to spa-tial confinement,annual survival of marked male deer averaged 36.7%-42.5%.After spatial confinement,annu-al survival increased on average for males(58%-99%)and females(77%-98%).Females showed high levels of site fidelity(>99%)prior to spatial confinement,whereas males showed much less site fidelity(≤4.5%for the 2 top-ranking models).During spatial confinement,the semi-impermeable fence effectively increased site fidelity of males(≥56%).These results stem from long-term study(23 years)of a large herbivore experiencing changes to life-history,resulting from changes in management that were applied to the population and aimed at altering population demographics,for sustainability of a harvestable population of deer.

关键词： conservation deer fidelity mortality Odocoileus virginianus population dynamics

Salivary Gland Branching Morphogenesis——Recent Progress and Future Opportunities

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Oral Science 2010年第3期2卷 117-126页

作者： Jeff Chi-feng Hsu kenneth M.Yamada Laboratory of Cell and Developmental Biology National Institute of Dental and Craniofacial ResearchNational Institutes of Health

Salivary glands provide saliva to maintain oral health, and a loss of salivary gland function substantially decreases quality-of-life. Understanding the biological mechanisms that generate salivary glands during embryonic development may identify novel ways to regenerate function or design artificial salivary glands. This review article summarizes current research on the process of branchingmorphogenesis of salivary glands, which creates gland structure during development. We highlight exciting new advances and opportunities in studies of cell-cell interactions, mechanical forces, growth factors, and gene expression patterns to improve our understanding of this important process.

关键词： salivary gland epithelium branching morpho-genesis fibronectin e-cadherin growth factor

Functional impact of microRNA regulation n models of extreme stress adaptation

在线全文

学校读者我要写书评

暂无评论

Journal of Molecular Cell Biology 2018年第2期10卷 93-101页

作者： Kyle K. Biggar kenneth B. Storey Institute of Biochemistry & Department of Biology Carleton University Ottawa ON K1S 5B6 Canada

When confronted with severe environmental stress, some animals are able to undergo a substantial reorganization of their cellular environment that enables long-term survival. One molecular mechanism of adaptation that has received considerable attention in recent years has been the action of reversible transcriptome regulation by microRNA. The implementation of new computational and high-throughput experimental approaches has started to uncover the vital contributions of microRNA towards stress adaptation. Indeed, recent studies have suggested that microRNA may have a major regulatory influence over a number of cellular processes that are essential to prolonged environmental stress survival. To date, a number of studies have highlighted the role of microRNA in the regulation of a metabolically depressed state, documenting stress-responsive microRNA expression during mammalian hibernation, frog and insect freeze tolerance, and turtle and marine snail anoxia tolerance. These studies collectively indicate a conserved principle of microRNA stress response across phylogeny. As we are on the verge of dissecting the role of microRNA in environmental stress adaptation, this review summarizes recent research advances and the hallmark expression patterns that facilitate stress survival.

关键词： hypometabolism metabolism temperature metabolic rate depression stress response

Technology advancing the study of animalcognition： using virtual reality to presentvirtually simulated environments to investigatenonhuman primate spatial cognition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2017年第1期63卷 97-108页

作者： Francine L. DOLINS kenneth SCHWeLLeR Scott MILNe Department of Behavioral Sciences University of Michigan-Dearborn Dearborn MI 48128 USA Ape Cognition and Conservation Initiative Des Moines IA USA Impact Madagascar Nanisana Antananarivo 101Madagascar Africa

Virtual simulated environments provide multiple ways of testing cognitive function and evaluatingproblem solving with humans （e.g., Woollett et al. 2009）. The use of such interactive technologyhas increasingly become an essential part of modern life （e.g., autonomously driving vehicles, glo-bal positioning systems （GPS）, and touchscreen computers; Chinn and Fairlie 2007; Brown 2011）.While many nonhuman animals have their own forms of technology, such as chimpanzees whocreate and use tools, in captive animal environments the opportunity to actively participate withinteractive technology is not often made available. exceptions can be found in some state-of-the-art zoos and laboratory facilities （e.g., Mallavarapu and Kuhar 2005）. When interactive technologyis available, captive animals often selectively choose to engage with it. This enhances the animal＇ssense of control over their immediate surroundings （e.g., Clay et al. 2011; Ackerman 2012）. Suchself-efficacy may help to fulfill basic requirements in a species＇ daily activities using problem solv-ing that can involve foraging and other goal-oriented behaviors. It also assists in fulfilling thestrong underlying motivation for contrafreeloading and exploration expressed behaviorally bymany species in captivity （Young 1999）. Moreover, being able to present nonhuman primates vir-tual reality environments under experimental conditions provides the opportunity to gain insightinto their navigational abilities and spatial cognition. It allows for insight into the generation andapplication of internal mental representations of landmarks and environments under multiple con-ditions （e.g., small- and large-scale space） and subsequent spatial behavior. This paper reviewsmethods using virtual reality developed to investigate the spatial cognitive abilities of nonhumanprimates, and great apes in particular, in comparison with that of humans of multiple age *** make recommendations about training, best practices, and also pi

关键词： animal cognition, apes, bonobos, chimpanzees, nonhuman primates, spatial cognition, virtual reality.

Characterization of ASTeR GDeM elevation data over vegetated area compared with lidar data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Digital earth 2015年第3期8卷 198-211页

作者： Wenjian Ni Guoqing Sun kenneth J.Ranson State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingChina Department of Geographical sciences University of MarylandCollege ParkMDUSA Biospheric Sciences Branch NASA’s Goddard Space Flight CenterGreenbeltMDUSA

Current researches based on areal or spaceborne stereo images with very high resolutions(<1 m)have demonstrated that it is possible to derive vegetation height from stereo *** second version of the Advanced Spaceborne... 详细信息

Current researches based on areal or spaceborne stereo images with very high resolutions(e demonstrated that it is possible to derive vegetation height from stereo *** second version of the Advanced Spaceborne Thermal emission and Reflection Radiometer Global Digital elevation Model(ASTeR GDeM)is the state-of-the-art global elevation data-set developed by stereo ***,the resolution of ASTeR stereo images(15 m)is much coarser than areal stereo images,and the ASTeR GDeM is compiled products from stereo images acquired over 10 *** forest disturbances as well as forest growth are inevitable in 10 years time *** this study,the features of ASTeR GDeM over vegetated areas under both flat and mountainous conditions were investigated by comparisons with lidar *** factors possibly affecting the extraction of vegetation canopy height considered include(1)co-registration of DeMs;(2)spatial resolution of digital elevation models(DeMs);(3)spatial vegetation structure;and(4)terrain *** results show that the accurate coregistration between ASTeR GDeM and national elevation dataset(NeD)is necessary over mountainous *** correlation between ASTeR GDeM minus NeD and vegetation canopy height is improved from 0.328 to 0.43 by degrading resolutions from 1 arc-second to 5 arc-second and further improved to 0.6 if only homogenous vegetated areas were considered.

关键词： vegetation canopy height ASTeR GDeM NeD photogrammetry stereo-mapping

Luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline indole complexes as biological probes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2010年第10期53卷 2091-2098页

作者： LO kenneth Kam-Wing LeUNG Arthur Ho-Hon Department of Biology and Chemistry City University of Hong Kong

Four luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline complexes appended with an indole moiety [Ir(N^C)2(N^N)] (PF6) (HN^C = 2-phenylpyridine, Hppy; N^N = 2-(N-(2-(indole-3-acetamido)ethyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinox- aline, dpqC2indole (1a), N^N = 2-(N-(6-(indole-3-acetamido)hexyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinoxaline, dpqC6indole (1b); HN^C = 7,8-benzoquinoline, Hbzq, N^N = dpqC2indole (2a), N^N = dpqC6indole (2b)) have been synthesized and characterized. Upon irradiation, all the complexes displayed moderately intense and long-lived luminescence under ambient condi-tions and in 77 K glass. On the basis of the photophysical data, the emission of the complexes has been assigned to an excited state of triplet metal-to-ligand charge-transfer (3MLCT) ((dπ(Ir)→π*(N^N)) character. Cyclic voltammetric studies revealed indole-based and iridium-based oxidations at ca. +1.10 V and +1.24 V vs. SCe, respectively, and ligand-based reductions at ca. -1.07 to-2.29 V vs. SCe. The interactions of the complexes with an indole-binding protein, bovine serum albumin (BSA), have been examined by emission titrations.

关键词： binding indole iridium luminescence probes

A critical review of ferritin as a drug nanocarrier:Structure,properties,comparative advantages and challenges

在线全文

学校读者我要写书评

暂无评论

Particuology 2022年第5期20卷 65-84页

作者： Shuang Yin kenneth Davey Sheng Dai Yongdong Liu Jingxiu Bi School of Chemical engineering&Advanced Materials Faculty of EngineeringComputer and Mathematical Sciences.University of AdelaideAdelaideAustralia Department of Chemical engineering Brunei University LondonUxbridge UB83PHUnited Kingdom State Key Laboratory of Biochemistry engineering.Institute of Process engineering Chinese Academy of Sciences.BeijingChina

Ferritin stores and releases iron ions in *** is globally important as a drug *** is because of its unique hollow-spherical structure,desirable stability and biological *** drug-loading approaches plus various functionalization approaches have been developed to improve ferritin in response to differing demands in disease ***,we critically review ferritin drug delivery and evaluate its diverse drug-loading and functionalization approaches,we:(1)Introduce basic structural and property information related to ferritin as a drug nanocarrier;(2)Contrast in detail the different means to load drugs and the selection of drug loading means;(3)Discuss multiple ferritin functionalization approaches,together with related advantages and potential risks;and,(4)Compare ferritin with alternative,commonly-used drug *** conclude that despite that no drugs based on ferritin are commercially available,the market potential for it is significant,and evaluate future research *** from this work will be of immediate benefit and interest to a wide range of researchers and manufacturers for drug delivery using ferritin.

关键词： Ferritin Drug delivery Drug nanocarrier Protein functionalization

Map of Mafic Dyke Swarms and Related Units of Russia and Adjacent Regions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(english edition) 2016年第S1期90卷 22-23页

作者： Richard e.eRNST kenneth L.BUCHAN Svetlana BOTSYUN Department of earth Sciences Carleton University Faculty of Geology and Geography Tomsk State University Geological Survey of Canada Natural Resources Canada Laboratoire des Sciences du Climat et de l'environnement LSCE/IPSL CEA-CNRS-UVSQ Université Paris-Saclay

Work is currently underway to produce a map in Arc GISTM 10 of the mafic dyke swarms and related units(volcanics,sills and layered intrusions)of Russia and adjacent regions at a scale of 1:5,000,*** the past

关键词： Map of Mafic Dyke Swarms and Related Units of Russia and Adjacent Regions

Determination of slug permeability factor for pressure drop prediction of slug flow pneumatic conveying

在线全文

学校读者我要写书评

暂无评论

Particuology 2008年第5期6卷 307-315页

作者： kenneth C.Williams Mark G.Jones Tobias Krull Centre for Bulk Solids and Particulate Technology The University of NewcastleCallaghanNSW 2308Australia

Current models for pressure drop prediction of slug flow pneumatic conveying in a horizontal pipeline system assume some type of steady state conditions for prediction, which limits their capability for increased predictive accuracy relative to experimental data. This is partly because of the nature of slug flow pneumatic conveying system, which, as a dynamic system, never becomes stable. By utilising conservation of mass （airflow）, a dynamic pressure analysis model is proposed on the basis of the derivative of the upstream pressure behaviour. The rate of air permeation through slug, one of the important factors in the conservation model, is expressed as a function of a slug permeability factor. Other factors such as slug velocity, slug length and the fraction of stationary layer were also considered. Several test materials were conveyed in single-slug tests to verify the proposed pressure drop model, showing good agreement between the model and experimental results.

关键词： Slug flow pneumatic conveying Pressure drop Air mass conversation Slug permeability factor