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作为“癌前”病变标志的谷胱甘肽S-转移酶同工酶

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科学通报 1992年第14期37卷 1317-1320页

作者：左瑾方福德丁濂 w.d.henner 谢大英中国医学科学院基础医学研究所北京100005 Oregon Health Sciences University Portland USA 中国预防医学科学院劳动卫生与职业病研究所北京100050

在肿瘤病因中,80％以上为化学因素所致。化学致癌的两阶段学说亦已被普遍接受。此学说认为“起动”是不可逆的,但可阻断其向细胞癌变方向发展。因而探讨用客观指标检测“起动”细胞的不可逆改变对于阐明癌变原理。确定“癌前”

关键词： GST同工酶化学致癌病变标志

谷胱甘肽S-转移酶同工酶-pi基因的转录激活

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科学通报 1993年第20期38卷 1919-1920页

作者：左瑾方福德丁濂陈晋彦王淑华 w.d.henner 中国医学科学院基础医学研究所北京100005 Oregon Health Sciences University PortlandUSA

文献报道,多种肿瘤细胞与相应的正常细胞相比,谷胱甘肽 S-转移酶同工酶-pi(π)(以下简称 GST-pi(π))的合成量和活性均有明显增加,在人食管癌细胞中 GST-πmRNA 表达水平比正常食管粘膜组织细胞显著增高,在抗药性人肿瘤细胞中。

关键词： GST-pi 基因转录激活肿瘤细胞

谷胱甘肽S-转移酶pi作为肿瘤研究的新系统

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中国肿瘤 1995年第7期4卷 25-27页

作者：方福德左瑾丁濂王燕云高惠兰张敏磊杨俊保 w．d．henner 中国医学科学院基础医学研究所北京100005 美国哈佛大学dana-Farber癌症研究所

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.d.Küntz d.Koutroumpa w.R.dunn A.Foster F.S.Porter d.G.Sibeck B.walsh The Henry A.Rowland department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

while we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).with a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

BMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development

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Neural Regeneration Research 2024年第2期19卷 447-457页

作者： Michael w.weible II Michael d.Lovelace Hamish d.Mundell Tsz wai Rosita Pang Tailoi Chan-Ling Bosch Institute Discipline of Anatomy and Histology(F13)University of SydneySydneyNSWAustralia School of Environment and Science Griffith UniversityNathanQLDAustralia discipline of Medicine Nepean Clinical SchoolFaculty of Medicine and HealthUniversity of SydneyKingswoodNSWAustralia New South wales Brain Tissue Resource Centre School of Medical SciencesFaculty of Medicine and HealthUniversity of SydneyCharles Perkins Centre(D17)SydneyNSWAustralia

Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well ***-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is *** was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory *** and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,Cd34/*** immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/Cd118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,*** neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent *** cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage ***-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in *** is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal *** data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterize

关键词： BMPRⅡ bone morphogenetic protein histotypic human spinal cord development leukemia inhibitory factor neurosphere organotypic reaggregate sensory columns

SMILE soft X-ray Imager flight model CCd370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons d.J.Hall O.Hetherington T.w.Buggey T.Arnold M.w.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCd370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCds have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCd soft X-ray imager characterisation SMILE

determining minimum sample size for the conditioned Latin hypercube sampling algorithm

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Pedosphere 2024年第3期34卷 530-539页

作者： daniel d.SAURETTE Asim BISwAS Richard J.HECK Adam w.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(dSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental *** to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the dSM *** advances in sampling design,a critical gap remains in determining the number of samples required for dSM *** propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-diaconis rule for determining optimal bin *** preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the *** on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample *** technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of *** results showed increasing minimum sample size with an increase in the QR *** sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%*** technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

Perturbations in the earthworm metabolite profile during a two-week exposure to metformin

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Emerging Contaminants 2024年第3期10卷 221-229页

作者： J.d.Gillis G.w.Price S.O.Prasher department of Bioresource Engineering McGill UniversityFaculty of Agricultural and Environmental SciencesMacdonald-Stewart Building MS1-02721111 Lakeshore RoadSainte-Anne-de-BellevueQuebecH9X 3V9Canada department of Engineering Dalhousie UniversityFaculty of Agriculture39 Cox RoadPO Box 550TruroNova ScotiaB2N 5E3Canada

Metformin is among the most prescribed pharmaceuticals in many countries,and as a result has shown up in biosolids derived from municipal wastewater treatment that are destined for land *** humans taking metformin,the effects include reduced glucose uptake in the intestine,a reduction in gluconeogenesis,increased oxidation of fatty acids,and reduced fatty acid *** effects of metformin on soil-dwelling organisms are not well *** study tested the effects of metformin exposure(0,10,40,160,640μg g^(-1))on the earthworm(***)at four time points(6 h,2 d,7 d,and 14 d)using GC-MS to reveal sub-lethal effects and elucidate potential modes of action for *** were no mortalities observed,and earthworms exposed to the highest concentrations(160 and 640μg g^(-1))gained weight relative to the control on days 7 and *** reductions on day 7 were observed for glucose and malic acid(consistent with a reduction in gluconeogenesis),and for palmitic and margaric acid(consistent with increased oxidation and reduced synthesis of fatty acids).Lactic acid ranked first and second among canonicals 1 and 2 respectively and led to significant differences in discriminant scores across concentration and *** levels increased to equal or greater than the control on day 14,likely caused by reduced exposure as metformin is reported to be readily transformed by microorganisms under aerobic *** observations were consistent with the known effects of metformin in humans,and suggests that a similar mode of action exists in earthworms.

关键词： Metabolites Toxicity Earthworms Metformin GC-MS

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped HfO_(2)thin films

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Chinese Physics B 2024年第9期33卷 637-643页

作者： S X Chen M M Chen Y Liu d w Cao G J Chen department of Microelectronics Jiangsu UniversityZhenjiang 212013China department of Physics Jiangsu UniversityZhenjiang 212013China Guangdong–Hong Kong–Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric HfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with Si-based complementary metal-oxide-semiconductor(CMOS)***,the crystallization of polar orthorhombic phase(o-phase)HfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric HfO_(2)thin ***,the crystallization of o-phase HfO_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped HfO_(2)(HfO_(2):Al)thin films on(111)-oriented Si substrate has been *** analysis has suggested that nonpolar monoclinic HfO_(2):Al grown on(111)-oriented Si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase HfO_(2)in the as-grown HfO_(2):Al thin *** addition,the in-plane lattice of(111)-oriented Si substrate matches well with that of(111)-oriented o-phase HfO_(2),which further thermally stabilizes the o-phase HfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric HfO_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain HfO_(2)