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牙龈卟啉单胞菌超声提取物对人牙周膜干细胞骨向分化的影响

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现代口腔医学杂志 2007年第6期21卷 603-605页

作者：侯建霞 peter m loomer Barron Hong 北京大学口腔医学院 100081 美国加利福尼亚大学旧金山分校

目的本研究目的是检测牙龈卟啉单胞菌(Porphyromonas gingivalis,***)2561超声提取物对人牙周膜干细胞(Human periodontal ligament stemcells,hPDLSCs)的增殖及其骨向分化相关蛋白表达的影响。方法标准厌氧培养环境下培养***。收集细... 详细信息

目的本研究目的是检测牙龈卟啉单胞菌(Porphyromonas gingivalis,***)2561超声提取物对人牙周膜干细胞(Human periodontal ligament stemcells,hPDLSCs)的增殖及其骨向分化相关蛋白表达的影响。方法标准厌氧培养环境下培养***。收集细菌菌落,离心,制备细菌的超声提取物,然后以不同的浓度加入hPDLSCs的培养液中。培养六天后观察hPDLSCs的增殖及碱性磷酸酶(Alkaline phosphatase,ALPase)的表达。提取蛋白并用Western Blotting检测骨黏结蛋白(Osteonectin,ON)的表达。结果与对照组相比,***明显抑制hPDLSCs的生长(P<0.05),显著降低了hPDLSCs中ALPase的表达(P<0.05);1μg/***上调ON的表达,而100μg/***明显下调ON的表达。结论这些结果提示作为牙周炎病原菌,大量的***可能,至少部分通过抑制hPDLSCs的增殖及其骨向分化能力,抑制了牙周炎症所致牙周组织破坏后牙周组织的自我修复能力。

关键词：牙周膜干细胞牙龈卟啉单胞菌骨向分化碱性磷酸酶骨黏结素

牙龈卟啉单胞菌超声提取物对hPDLSCs表达VEGF的影响

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实用口腔医学杂志 2007年第2期23卷 176-179页

作者：侯建霞邵磊 peter m loomer Barron Hong 北京大学口腔医学院牙周科 100081 东风汽车公司襄樊医院口腔科美国加利福尼亚大学旧金山分校牙周科

目的:观察牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)超声提取物对人牙周膜干细胞(human per-iodontal ligament stem cells,hPDLSCs)表达血管内皮生长因子(vascular endothelial growth factor,VEGF)及基质金属蛋白酶-9(matrix metalloproteinase-9,mmP-9)的影响。方法:标准厌氧培养环境下培养Pg,收集细菌菌落,离心,制备细菌的超声提取物,然后以不同的浓度加入hPDLSCs的培养液中。培养6d,分别观察第2、4、6天时hPDLSCs的增殖情况。提取蛋白并用Western Blotting法检测VEGF和mmP-9的表达。结果:与对照组相比,第2天时,10μg/ml和100μg/mlPg轻度促进hPDLSCs的生长,第4天时,10μg/ml和100μg/mlPg则明显抑制hPDLSCs的生长(Pml和10μg/mlPg上调VEGF的表达,100μg/mlPg明显抑制VEGF的表达;3种浓度的Pg均上调hPDLSCs中mmP-9的表达。结论:作为牙周炎病原菌,大量的Pg可能通过抑制hPDLSCs的生长增殖,抑制局部血管重建以及加速细胞外基质的降解而降低了牙周组织的自我修复能力。

关键词：牙周膜干细胞牙龈卟啉单胞菌血管内皮生长因子基质金属蛋白酶

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低氧调节人牙周膜干细胞的骨向分化

中华口腔医学杂志 2009年第Z1期44卷 106-106页

作者： HOU Jian-xia peter m loomer DivisionofPeriodontology UniversityofCaliforniaSchoolofDentistry SanFrancisco USA DepartmentofPeriodontology PekingUniversitySchoolandHospitalofStmatology BeijingChina DivisionofPeriodontology UniversityofCaliforniaSchoolof DivisionofPeriodontology UniversityofCaliforniaSchoolofDentistry SanFrancisco USA DepartmentofPeriodontology PekingUniversitySchoolandHospitalofStmatology BeijingChina DivisionofPeriodontology UniversityofCaliforniaSchoolof

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Target blood pressure in diabetes patients with hypertension——What is the accumulated evidence in 2011?

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第8期12卷 611-623页

作者： peter m.NILSSON Department of Clinical Sciences Lund UniversityUniversity Hospital

There is overwhelming evidence that hypertension is an important risk factor for both macrovascular and microvascular complications in patients with diabetes,but the problem remains to identify appropriate goals for preventive therapies.A number of guidelines (the European Society of Cardiology (ESC)/European Association for the Study of Diabetes (EASD) 2007,the Joint National Committee (JNC)-Ⅶ 2003,the American Diabetes Association (ADA) 2011) have for example advocated a blood pressure goal of less than 130/80 mmHg,but this suggestion has been challenged by findings in recent trials and meta-analyses (2011).The European Society of Hypertension (ESH) therefore recommends a systolic blood pressure goal of "well below" 140 *** on evidence from both randomized controlled trials (hypertension optimal treatment (HOT),action in diabetes and vascular disease:preterax and diamicron mR controlled evaluation (ADVANCE),action to control cardiovascular risk in diabetes (ACCORD)) and observational studies (ongoing telmisartan alone and in combination with ramipril global endpoint trial (ONTARGET),international verapamil-trandolapril study (INVEST),treat to new targets (TNT),and the National Diabetes Register (NDR)),it has been shown that the benefit for stroke reduction remains even at lower achieved blood pressure levels,but the risk of coronary events may be uninfluenced or even increased at lower systolic blood pressure *** a recent meta-analysis,it was therefore concluded that the new recommended goal should be 130-135 mmHg systolic blood pressure for most patients with type 2 *** risk factors should also be controlled with a more ambitious strategy applied in the younger patients with shorter diabetes duration,but a more cautious approach in the elderly and frail patients with a number of vascular or non-vascular *** patients from East Asia,such as China,the stroke risk is relatively higher than the risk of coronary *** must al

关键词： Blood pressure Cardiovascular Diabetes Goal Hypertension Treatment

Quantum corrections for Boltzmann equation

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Science China(Physics,mechanics & Astronomy) 2008年第9期51卷 1229-1239页

作者： m. Levy peter Department of Physics New York University

We present the lowest order quantum correction to the semiclassical Boltzmann distribution function,and the equation satisfied by this correction is given. Our equation for the quantum correction is obtained from the conventional quantum Boltzmann equation by explicitly expressing the Planck constant in the gradient approximation,and the quantum Wigner distribution function is expanded in pow-ers of Planck constant,too. The negative quantum correlation in the Wigner dis-tribution function which is just the quantum correction terms is naturally singled out,thus obviating the need for the Husimi’s coarse grain averaging that is usually done to remove the negative quantum part of the Wigner distribution function. We also discuss the classical limit of quantum thermodynamic entropy in the above framework.

关键词： quantum Boltzmann equation Wigner distribution function quantum correction

Testing flexible polymer solar cells in near-space

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National Science Review 2023年第5期10卷 105-106页

作者： peter müller-Buschbaum Department of Physics TUM School of Natural Sciencesand Heinz Maier-Leibnitz-Zentrum(MLZ)Technical University of Munich

Since the big success of the Vanguard1 mission,being the first solar-powered satellite,the use of solar cells in space developed very ***,conventional solar cell technologies for space are based on silicon and GaAs **...

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Fluid and Osmotic Pressure Balance and Volume Stabilization in Cells Dedicated to Professor Karl Stark Pister for his 95th birthday

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Computer modeling in Engineering & Sciences 2021年第12期129卷 1329-1350页

作者： peter m.Pinsky Department of mechanical Engineering Stanford UniversityStanford94305CAUSA

A fundamental problem for cells with their fragile membranes is the control of their *** primordial solution to this problem is the active transport of ions across the cell membrane to modulate the intracellular osmotic *** this work,a theoretical model of the cellular pump-leak mechanism is proposed within the general framework of linear nonequilibrium *** model is expressed with phenomenological equations that describe passive and active ionic transport across cell membranes,supplemented by an equation for the membrane potential that accounts for the electrogenicity of the ionic *** active ionic transport,the model predicts that the intracellular fluid pressure will be balanced by the osmotic pressure and a new pressure component that arises from the active ionic fluxes.A model for the pump-leak mechanism in an idealized human cell is introduced to demonstrate the applicability of the proposed theory.

关键词： Pump-leak mechanism cell volume regulation active ion transport ion pump membrane transport cell mechanics modified Kedem-Katchalsky equations nonequilibrium thermodynamics phenomenological equations

Terrestrial denitrification:challenges and opportunities

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Ecological Processes 2012年第1期1卷 1-11页

作者： peter m Groffman Cary Institute of Ecosystem Studies 2801 Sharon TurnpikeMillbrookNY 12545USA

Denitrification is a process of great environmental importance but is difficult to study in terrestrial *** for quantifying the process are problematic,variability in activity is high,and temporal and spatial scaling challenges are *** methods are problematic for a variety of reasons;they change substrate concentrations,disturb the physical setting of the process,lack sensitivity or are prohibitively costly in time and *** fundamentally,it is very difficult to quantify the dominant end-product(N_(2))of denitrification given its high background concentration in the *** and temporal variation in denitrification is high due to control of the process by multiple factors(oxygen,nitrate,carbon,pH,salinity,temperature etc.)that each vary in time and space.A particular challenge is that small areas(hotspots)and brief periods(hot moments)frequently account for a high percentage of N gas flux *** phenomena are challenging to account for in measurement,modeling and scaling *** need for scaling is driven by the fact that there is a need for information on this microscale process at the ecosystem,landscape and regional scales where there are concerns about nitrogen effects on soil fertility,water quality and air *** this review,I outline the key challenges involved with denitrification and then describe specific opportunities for making progress on these challenges including advances in measurement methods,new conceptual approaches for addressing hotspot and hot moment dynamics,and new remote sensing and geographic information system–based scaling *** of these opportunities suggests that we are poised to make great improvements in our understanding of terrestrial *** improvements will increase our basic science understanding of a complex biogeochemical process and our ability to manage widespread nitrogen pollution problems.

关键词： scaling process landscape

Simulation and calibration of granules using the discrete element method

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Particuology 2014年第1期12卷 40-43页

作者： peter müller Jürgen Tomas Institute of Process Engineering Mechanical Process EngineeringOtto-von-Guericke University MagdeburgUniversitätsplatz 239106 MagdeburgGermany

The discrete element method （DEm）, developed by Cundall and 5track to solve geomecnamcai problems, is used to simulate the mechanical behavior of granules. According to the DEm, an individ ual granule can be modeled as a realistic mechanical system consisting of primary particles bonded by interaction forces. Cranulometric properties of the model material, zeolite 4A, have been measured to determine their macro properties. To investigate the compression behavior, a compression test was performed using a strength tester on single granules between two pistons. A modeled granule consisting of more than 22,000 primary particles was generated. The micro properties of the modeled granule have been precisely set to allow its macro properties to be equivalent to the macro properties of zeolite 4A granules. To calibrate the mechanical properties, diametrical compression was simulated using two rigid walls stressed at a constant stressing velocity, The force-displacement curve of the modeled granule at compression has been calibrated by the experimental curve of zeolite 4A.

关键词： Discrete element method material behavior Granulation