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| 1 | The Chemistry of Niobium Mineralisation at Bayan Obo,Inner Mongolia,China:Constraints on the Hydrothermal Precipitation and Alteration of Nb-Minerals显示文摘As well as world class Fe and REE resources the Bayan Obo mineral deposits also hosts significant niobium resources(estimated as 2.2 Mt Nb with an average grade of 0.13 wt% Nb).Niobium in this study is primarily hosted in aeschynite-(Ce) and(Nd),but with subsidiary amounts of pyrochlore,fergusonite-(Ce),fersmite and columbite.Here we report on the paragenetic and textural setting of aeschynite,pyrochlore and fergusonite in the main ore bodies and in a carbonatite dyke.Niobium in a carbonatite sample is hosted in a phase tentatively(due to significant Ca,Mn and Ti contents) identified as fergusonite-(Ce).Aeschynite occurs overgrowing foliation in banded ores,in fractures and vugs in aegirine-rich rocks and in calcite veins.The composition in all settings is similar,but some examples in banded ores develop significant zonation in Y,Th and the REE,inferred to relate to buffering of halogen acid species to low levels by dissolution and fluoritisation of calcite,and the preferential precipitation of LREE from solution due to lower mineral solubility products compared to the HREE.Although lower in total concentration the ratios of REE in pyrochlore are similar to those of aeschynite and suggest the same metal source.The crystallisation of pyrochlore probably relates to growth in paragenetic settings where carbonates had already been eliminated and hence the buffering of F-species activities in the hydrothermal fluid was reduced.Both aeschynite and pyrochlore show evidence of alteration.Primary alteration of aeschynite resulted in leaching of A-site cations(Ca,REE,Th) and Nb,addition of Fe,and ultimately replacement by Ba-Ti phases(baotite and bafertisite).Secondary,metamictisation enhanced,possibly supergene alteration of pyrochlore resulted in hydration,leaching of A-site cations leading to the development of lattice vacancies and increases in Si.The presence of hydrothermal Nb resources at Bayan Obo suggests there may be potential for further Nb discoveries in the area,whilst the trends in element mobility during alteration have significant implications for the utility of A-B oxides as components of materials for immobilisation of radionuclides. | Martin SMITH John SPRATT | 2012 | 地质学报2012，86，5： | 3 |
| 2 | Seasonal Variation in Stroke in the Hunter Region, Australia: A 5-Year Hospital-Based Study, 1995-2000显示文摘 | Yang Wang Christopher R. Levi John R. Attia Catherine A. D’Este Neil Spratt Janet Fisher | 2003 | Stroke: Journal of the American Heart Association2003，，5： | 2 |
| 3 | An Analysis of Prospective Risk Factors for Aortic Stiffness in Men: 20-Year Follow-Up From the Caerphilly Prospective Study显示文摘 | Carmel M. McEniery Michael Spratt Margaret Munnery John Yarnell Gordon D. Lowe Ann Rumley John Gallacher Yoav Ben-Shlomo John R. Cockcroft Ian B. Wilkinson | 2010 | Hypertension2010，，1： | 2 |
| 4 | Tranexamic acid for intracerebral haemorrhage within 2 hours of onset: protocol of a phase Ⅱ randomised placebo-controlled double-blind multicentre trial显示文摘Rationale Haematoma growth is common early after intracerebral haemorrhage(ICH),and is a key determinant of outcome.Tranexamic acid,a widely available antifibrinolytic agent with an excellent safety profile,may reduce haematoma growth.Methods and design Stopping intracerebral haemorrhage with tranexamic acid for hyperacute onset presentation including mobile stroke units(STOP-MSU)is a phase Ⅱ double-blind,randomised,placebo-controlled,multicentre,international investigator-led clinical trial,conducted within the estimand statistical framework.Hypothesis In patients with spontaneous ICH,treatment with tranexamic acid within 2 hours of onset will reduce haematoma expansion compared with placebo.Sample size estimates A sample size of 180 patients(90 in each arm)would be required to detect an absolute difference in the primary outcome of 20%(placebo 39%vs treatment 19%)under a two-tailed significance level of 0.05.An adaptive sample size re-estimation based on the outcomes of 144 patients will allow a possible increase to a prespecified maximum of 326 patients.Intervention Participants will receive 1 g intravenous tranexamic acid over 10 min,followed by 1 g intravenous tranexamic acid over 8 hours;or matching placebo.Primary efficacy measure The primary efficacy measure is the proportion of patients with haematoma growth by 24±6 hours,defined as either≥33%relative increase or≥6 mL absolute increase in haematoma volume between baseline and follow-up CT scan.Discussion We describe the rationale and protocol of STOP-MSU,a phase Ⅱ trial of tranexamic acid in patients with ICH within 2 hours from onset,based in participating mobile stroke units and emergency departments. | Nawaf Yassi Henry Zhao Leonid Churilov Bruce C V Campbell Teddy Wu Henry Ma Andrew Cheung Timothy Kleinig Helen Brown Philip Choi Jiann-Shing Jeng Annemarei Ranta Hao-Kuang Wang Geoffrey C Cloud Rohan Grimley Darshan Shah Neil Spratt Der-Yang Cho Karim Mahawish Lauren Sanders John Worthington Ben Clissold Atte Meretoja Vignan Yogendrakumar Mai Duy Ton Duc Phuc Dang Nguyen Thai My Phuong Huy-Thang Nguyen Chung Y Hsu Gagan Sharma Peter J Mitchell Bernard Yan Mark W Parsons Christopher Levi Geoffrey A Donnan Stephen M Davis | 2022 | Stroke & Vascular Neurology2022，7，2： | 1 |
| 5 | 流行病学和临床研究中数据缺失的多重填补:机会和陷阱显示文摘许多研究都存在缺失数据。Jonathan | Jonathan A C Sterne Ian R White John B Carlin Michael Spratt Patrick Royston Michael G Kenward Angela M Wood James R Carpenter 张清(译) 张孔来(校) | 2009 | 英国医学杂志中文版2009，12，6： | 1 |
| 6 | Cancer Of The Colon: The Influence Of The No-Touch Isolation Technic On Survival Rates显示文摘 | RUPERT B. TUHNBULL KENNETH KYLE FRANK R. WATSON JOHN SPRATT | 1967 | Annals of Surgery1967，，3： | 1 |
| 7 | Time‐resolved MR angiography of renal artery stenosis in a swine model at 3 Tesla using gadobutrol with digital subtraction angiography correlation显示文摘 | John N. Morelli Fei Ai Val M. Runge Wei Zhang Xiaoming Li Peter Schmitt Gary McNeal Henrick J. Michaely Stefan O. Schoenberg Matthew Miller Clint M. Gerdes Spencer T. Sincleair Heidi Spratt Ulrike I. Attenberger | 2012 | J. Magn. Reson. Imaging2012，，： | 1 |
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