|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Decoupling of DNA damage response signaling from DNA damages underlies temozolomide resistance in glioblastoma cells显示文摘Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor in adults.Current therapy includes surgery,radiation and chemotherapy with temozolomide (TMZ).Major determinants of clinical response to TMZ include methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) promoter and mismatch repair (MMR) status.Though the MGMT promoter is methylated in 45% of cases,for the first nine months of follow-up,TMZ does not change survival outcome.Furthermore,MMR deficiency makes little contribution to clinical resistance,suggesting that there exist unrecognized mechanisms of resistance.We generated paired GBM cell lines whose resistance was attributed to neither MGMT nor MMR.We show that,responding to TMZ,these cells exhibit a decoupling of DNA damage response (DDR) from ongoing DNA damages.They display methylation-resistant synthesis in which ongoing DNA synthesis is not inhibited.They are also defective in the activation of the S and G2 phase checkpoint.DDR proteins ATM,Chk2,MDC1,NBS1 and gammaH2AX also fail to form discrete foci.These results demonstrate that failure of DDR may play an active role in chemoresistance to TMZ.DNA damages by TMZ are repaired by MMR proteins in a futile,reiterative process,which activates DDR signaling network that ultimately leads to the onset of cell death.GBM cells may survive genetic insults in the absence of DDR.We anticipate that our findings will lead to more studies that seek to further define the role of DDR in ultimately determining the fate of a tumor cell in response to TMZ and other DNA methylators. | Stewart P.Johnson Nancy Bullock Francis Ali Osman Darell D.Bigner Henry S.Friedman | 2010 | The Journal of Biomedical Research2010，24，6： | 6 |
| 2 | The complexity of sediment recycling as revealed by common Pb isotopes in K-feldspar显示文摘Detrital zircon U-Pb geochronology has become the gold standard in evaluating source to sink relationships in sedimentary basins. However, the physical and chemical robustness of zircon, which make it such a useful mineral for provenance studies, is also a hindrance as zircon can be recycled through numerous sedimentary basins, thus obscuring the first cycle source to sink relationship. An elegant approach to addressing this potential issue is to compare the Pb isotope composition of detrital K-feldspar, a mineral which is unlikely to survive more than one erosion-transport-deposition cycle, with that of magmatic K-feldspar from potential basement source terranes. Here we present new in situ Pb isotope data on detrital K-feldspar from two Proterozoic arkosic sandstones from Western Australia, and magmatic K-feldspar grains from potential igneous source rocks, as inferred by the age and Hf isotope composition of detrital zircon grains. The data indicate that the detrital zircon and K-feldspar grains could not have been liberated from the same source rocks, and that the zircon has most likely been recycled through older sedimentary basins. These results provide a more complete understanding of apparently simple source to sink relationships in this part of Proterozoic Western Australia. | Simon P.Johnson Christopher L.Kirkland Noreen J.Evans Brad J.McDonald Huntly N.Cutten | 2018 | Geoscience Frontiers2018，9，5： | 5 |
| 3 | 纽约3号大街53号街办公楼,美国显示文摘 | P.Johnson and J.Burgee Architeets | 1990 | 世界建筑1990，，04： | 1 |
| 4 | Genetic amniocentesis following multifetal pregnancy reduction does not increase the risk of pregnancy loss显示文摘 | Lynn K.McLean Mark I.Evans Robert J.Carpenter Jr Mark P.Johnson James D.Goldberg | 1998 | Prenat Diagn1998，，2： | 1 |
| 5 | Ultrasound screening for anencephaly at 10–14 weeks of gestation显示文摘 | S. P.Johnson N. J.Sebire R. J. M.Snijders S.Tunkel K. H.Nicolaides | 2002 | Ultrasound Obstet Gynecol2002，，1： | 1 |
| 6 | Linking gold mineralization to regional-scale drivers of mineral systems using in situ U-Pb geochronology and pyrite LA-ICP-MS element mapping显示文摘Proterozoic orogens commonly host a range of hydrothermal ores that form in diverse tectonic settings at different times. However, the link between mineralization and the regional-scale tectonothermal evolution of orogens is usually not well understood, especially in areas subject to multiple hydrothermal events.Regional-scale drivers for mineral systems vary between the different classes of hydrothermal ore, but all involve an energy source and a fluid pathway to focus mineralizing fluids into the upper crust. The Mount Olympus gold deposit in the Proterozoic Capricorn Orogen of Western Australia, was regarded as an orogenic gold deposit that formed at ca. 1738 Ma during the assembly of Proterozoic Australia. However,the trace element chemistry of the pyrite crystals closely resembles those of the Carlin deposits of Nevada,with rims that display solid solution gold accompanied by elevated As, Cu, Sb, Hg, and Tl, surrounding gold-poor cores. New SHRIMP UeP b dating of xenotime intergrown with auriferous pyrite and ore-stage alteration minerals provided a weighted mean^(207) Pb*/^(206) Pb* date of 1769 ± 5 Ma, interpreted as the age of gold mineralization. This was followed by two discrete episodes of hydrothermal alteration at 1727 ± 7 Ma and 1673 ± 8 Ma. The three ages are linked to multiple reactivation of the crustal-scale Nanjilgardy Fault during repeated episodes of intracratonic reworking. The regional-scale drivers for Carlin-like gold mineralization at Mount Olympus are related to a change in tectonic regime during the final stages of the intracratonic 1820 -1770 Ma Capricorn Orogeny. Our results suggest that substantial sized Carlin-like gold deposits can form in an intracratonic setting during regional-scale crustal reworking. | Imogen O.H.Fielding Simon P.Johnson Sebastien Meffre Jianwei Zi Stephen Sheppard Ross R.Large Birger Rasmusseng | 2019 | Geoscience Frontiers2019，10，1： | 1 |
| 7 | Is habitat linearity important for small mammal communities on farmland?显示文摘 | F. H.Tattersall D. W.Macdonald B. J.Hart P.Johnson W.Manley R.Feber | 2002 | Journal of Applied Ecology2002，，4： | 1 |
| 8 | 切割、焊接和加热用燃气显示文摘在金属制品的制造过程中 ,正如许多工艺所要求的那样 ,对钢材的氧燃料切割需要通过合理的选择来达到表现为最低成本和最高质量的最佳效果。本文将阐述市场上主要碳氢燃气的优缺点。这些燃气包括 :乙炔、丙烷、丙烯、天然气 (主要由甲烷组成 )和混合燃气如 MAPP。本文还讨论了安全性、燃气成本。 | Jeffrey P.Johnson 田松亚 孙国平 | 2000 | 国外机车车辆工艺2000，，5： | 1 |
| 9 | Connecting supplier and DoD blockchains for transparent part tracking显示文摘Blockchains have been around for more than ten years,and since 2015,a plethora of systems have been launched to target more flexible use cases.More recently,several enterprise blockchain systems,such as Consensys Quorum and Hyperledger Fabric,have been launched to make blockchain simpler to apply in complex organizational configurations.In this paper,we identify a specific Department of Defense use case,extrapolate requirements,and perform a thorough assessment of the different layers of the blockchain stack to identify the existing state of the art and undertake a gap analysis of the technology for this context.We describe a platform that meets many of these challenges and show how we architected,designed,and implemented a solution for this use case for deployment at NAVAIR.This solution connects transactions from two separate blockchain systems,Consensys Quorum and Hyperledger Fabric,by using a graph-based approach that preserves privacy while enabling full transparency across the military and supplier networks. | Francis Asuncion Adam Brinckman Dwayne Cole Jeffrey Curtis Matt Davis Timothy Dunlevy Calvin Farmer Andrew Harrison Daniel P.Johnson Joshua Joyce Chris Klubertanz Jonathan Lane John Martin Jarek Nabrzyski Joel Neidig Deysi Olivares Gregory Robinson Gabriel Rodriguez Chris Root Karen Rowand Al Salour Jeff Score David Scott Ian Taylor Chandler Thompson Huy Truong Xiqun Wang Dale Warren | 2021 | Blockchain(Research and Applications)2021，2，3： | 1 |
| 10 | 升温后泥炭孔隙水溶解有机碳浓度及其不稳定性:野外贫瘠沼泽地增温试验显示文摘北欧和北美的研究表明,近几十年来水生生态系统中溶解有机碳(DOC)浓度增加。尽管关于溶解有机碳提高的机制还没有定论,但是一般认为其根本原因在于升温、降水变率增加和大气沉降变化等气候变化因素。本实验历时长达3年,通过在泥炭地上方1.24 m处安装红外灯积极增温,测试了增温对泥炭孔隙水组成的影响。结果发现在泥炭地下5 c m处,生长季中各处理的平均温度(n=5)比对照处理高1.9±0.4℃(t=5.03,P=0.007)。同时,在泥炭地下25 c m处,生长季中各处理的孔隙水D O C浓度(73.4±3.2 m g/L)比对照处理(63.7±2.1 m g/L)高15%(t=4.69,P<0.001)。此外,升温后的处理中,D O C分解速率是实验室内对照处理的2倍,芳香性比对照组孔隙水更低(增温后泥炭在254 nm处的吸光度降低)。溶解有机氮(DON)浓度变化规律与DOC一致,每单位碳中溶解的氮随着温度升高而下降。以往的研究表明,在这个实验地,增温使净初级生产力增加;同时,几丁质酶和葡萄苷酶的活性增加。本实验观察到,增温条件下DOC浓度增加,可能是因为根际微生物和植物相互作用的结果。在能去质子化生物分子池中,也探测到增温后出现较多的、独特的含有较高双键(DBE)的含氮化合物(在通过超高分辨率离子电喷雾质谱鉴定达到的所有化合物中占16%),这些化合物可能是随着增温引起的植物、微生物和酶活性增加后的产物。随着泥炭地持续升温,相对不稳定的DOC含量升高,这可能导致地表径流中DOC浓度增加,还可能作为有效的电子供体(或者受体)源使陆地和水生环境中的CO2和CH4增加。 | Evan S.Kane Lynn R.Mazzoleni Carley J.Kratz John A.Hribljan Christopher P.Johnson Thomas G.Pypker Rodney Chimner 赵旋琪 王江静 赵红艳 刘莎莎 | 2016 | 腐植酸2016，，2： | 0 |
| 11 | Trends of seasonal forage yield changes of triticale in the southern Great Plains of the United States显示文摘Background:The focus of triticale breeding in the southern Great Plains of the United States has been to increase forage yield for autumn-winter seasons when most other forage species are dormant.This study aims to estimate the trends of seasonal yield changes over time.Methods:Yield trials had been conducted in a randomized complete block design for up to two decades.Seasonal yield changes over time were estimated using linear regression analysis.Results:The analysis revealed a significant positive relation between autumn forage yield(relative to common checks)and calendar years when the trials were conducted.The estimated improvement of autumn forage yield was about 1.9%per year on medium and heavy soil at Ardmore,Oklahoma,and about 5.4%per year on light soil at Burneyville,Oklahoma.However,winter forage yield change was minimal and the spring forage yield increase was negative,although this decline was not significant.Total forage yield improvements were about 0.6%and 0.7%per year at Ardmore and Burneyville,respectively.Similar results were also observed when years of cultivars'introduction were used instead.Conclusions:The results indicate a significant gain in autumn forage yield,but a minor gain in the total forage yield due to the yield tradeoff between the autumn and spring seasons. | Tadele T.Kumssa Joshua D.Anderson James P.Johnson Shawn Norton Malay C.Saha Michael A.Trammell James K.Rogers Twain J.Butler Xue-Feng Ma | 2022 | Grassland Research2022，1，3： | 0 |
| 12 | Impact of COVID-19-related lifestyle changes on diabetic macular edema显示文摘AIM:To assess diabetic macular edema(DME)progression during the early phases of the COVID-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office visits.METHODS:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of DME seen on 3 separate visits between January 2019 and July 2021.Period 1 was January 2019 to February 2020(considered pre-COVID-19),period 2 was March 2020 to December 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).Main outcome measures included visual acuity,body mass index(BMI),blood pressure(BP),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and DME treatment(s)received at each visit.To facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment Diabetic Retinopathy Study(ETDRS)-defined macular sectors as measured by OCT imaging.RESULTS:There was no change of BMI,systolic BP,and diastolic BP between any of the time periods.HbA1c showed a very small increase from period 1(7.6%)to period 2(7.8%,P=0.015)and decreased back to 7.6%at period 3(P=0.12).Macular thickness decreased for 100%of macular regions.The central macular thickness decreased across all 3 periods from 329.5 to 316.6μm(P=0.0045).After analysis of multiple variables including HbA1c,BMI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in DME.CONCLUSION:DME doesn’t worsen during the COVID-19 pandemic,instead sustaining a very small but statistically significant improvement.While identifying a mechanism behind our findings is beyond the scope of this study,potential explanations may include a delay in retinal changes beyond our study period,an unexpected increase in treatment frequency despite pandemic restrictions,and an unanticipated pandemic-related improvement in some lifestyle factors that may have had a positive impact on DME. | Bryce P.Johnson Yu-Guang He Zachary M.Robertson Angeline Wang Rafael L.Ufret-Vincenty | 2024 | International Journal of Ophthalmology(English edition)2024，17，1： | 0 |
| 13 | Observations of defect propagation in [100]-oriented opal-type photonic crystals显示文摘Charged colloidal suspensions have been used as experimental models for the study of crystal nucleation.Here we propose that the technique of template-assisted colloidal self-assembly can be used to visualize the effects of defect propagation in atomic crystal films produced using epitaxial growth.Templates with periodic line defects were used to grow [100]-oriented three-dimensional photonic crystals by means of the template-assisted colloidal self-assembly method,aided by capillary and gravitational forces.The defect propagation in the [100]-oriented photonic crystal was observed using scanning electron microscopy,both at the surface of the crystal and on cleaved facets.This method is useful in the understanding of defect propagation in the growth of colloidal films on templates-and the same approach may also prove useful for the understanding of atomic crystal growth on substrates with defects.Additionally,the deliberate incorporation of line defects may prove valuable as a way of introducing waveguide channels into three-dimensional photonic crystals. | 金崇君 Richard M.De La Rue Nigel P.Johnson | 2008 | Chinese Physics B2008，17，4： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员