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铂族元素在地壳中的富集:以布什维尔德杂岩为例(英文)

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地学前缘 2008年第5期15卷 264-297页

作者： Tony Naldrett judith Kinnaird Allan Wilson Gordon Chunnett School of Geosciences University of the WitwatersrandJohannesburgSouth Africa Anglo Platinum JohannesburgSouth Africa

地幔是地壳铂族元素富集的主要源库。铂族元素迁移主要有两个途径：（1）地慢部分熔融物质侵入地壳；（2）地幔板片就位于俯冲/碰撞带。前一途径比后一途径重要得多。地幔物质进入地壳造成铂族元素富集并成为可供开采的主矿产而非副产... 详细信息

地幔是地壳铂族元素富集的主要源库。铂族元素迁移主要有两个途径：（1）地慢部分熔融物质侵入地壳；（2）地幔板片就位于俯冲/碰撞带。前一途径比后一途径重要得多。地幔物质进入地壳造成铂族元素富集并成为可供开采的主矿产而非副产品，这一过程可包含许多成矿作用机制：（i）基性侵入体中Ni-Cu硫化物矿浆的发育，岩浆冷却与分离结晶作用导致富含Cu，Pt，Pd的硫化物矿浆的形成；（ii）层状侵入体一定层位形成高品位的铂族元素硫化物层，伴生或不伴生铬铁岩；（iii）富铂族元素及硫化物的岩浆沿着层状侵入体的边缘就位；（iv）直至层状侵入体结晶分异作用晚期的硫化物不混溶滞后分离；（v）不发育硫化物不混溶作用的铬铁矿结晶作用；（vi）低程度硫化物浸染带中的热液作用与铂族元素富集；（vii）乌拉尔一阿拉斯加型侵入体重结晶过程中的铂族元素与铬铁矿的次生富集作用，岩体在风化过程中形成砂矿床；（viii）黑色页岩形成过程中Pt的富集。南非布什维尔德火成杂岩蕴藏世界Pt资源的75％，Pd资源的54％，Rh资源的82％，并具有（ii）、（iii）、（iv）、（v）、（vi）成矿作用的实例。在这些作用中，作用（ii）形成的现有经济储量和资源量占90％，作用（iii）占9％。merensky矿层（占总资源量30％）是一个铂族元素富集层位，它含1～3铬铁矿薄层，在可采宽度内硫化物平均含量为1％～3％（质量分数）。硫化物一般被认为是铂族元素的主要聚集体。该矿层由两个或两个以上含硫化物的基性热岩浆上升；12聚而成。这些岩浆的汇聚造成超镁铁质堆晶岩的厚度（主要是斜方辉石岩，某些地区包括橄榄岩）变化于50cm至数米之间。开采通常集中在厚度不到1m的地带。矿层的成因至今仍存在争议，一些观点认为铂族元素来自下部上升的热液流体，另一些观点认为铂族元素来自上部岩浆的硫化物沉降作用，并形成了merensky辉石岩。已经知道矿层上覆的辉石岩、苏长岩和斜长岩中矿物来自两种岩浆类型：一种富含mgO（12％，质量分数）和Cr，而贫A12O3（12％）；另一种含典型的粒玄岩成分。UG-2铬铁岩含有全部经济资源量的58％，由-0．6～1m厚的铬铁岩层（有时见辉石岩夹层）和上覆的1～3层由铬铁矿所构成的薄层。虽然硫化物被认为至少是某些情况下对铂族元素的富集起作用，但UG-2的硫化物含量（O．5％～1．5％）显著低于merensky矿层。UG-2层之下共有13个铬铁岩层位，所有的都含铂族元素，虽然铂族元素总含量和（Pt＋Pd）／（Ru＋Ir＋Os）比值远低于UG-2。UG-2内所含的辉石岩“夹层”具高的^87Sr／^86Sr比值，说明与顶部熔融岩石的混合促进了铬铁岩和硫化物的形成。作用（iii）的主要实例是Platreef。目前它占总资源量的9％。不过，沿该带正积极开展找矿勘探工作，这一比例将来还会提高。这一矿层的厚度比merensky和UG-2都要大，目前开采厚度达50多米。Platreef呈带状，上部为斜方辉石岩的堆晶岩；下部为辉石岩、长石辉石岩和苏长岩，它们与页岩、铁矿层和白云岩强烈相互作用，直接形成了底盘岩石。笔者认为Platreef是不同期次岩浆作用的结果，这些作用形成了不同的单元产物，包括布什维尔德主岩浆房的UG-2和merensky矿层。新的岩浆进入主岩浆房会造成先存岩浆移位、岩浆错动并会冲破岩浆房的壁。圆筒状、带状岩管中的超镁铁岩合极高的Pt品位，在布什维尔德杂岩的下部切穿堆晶层，被认为是热液再活化的产物。它们现在未被开采，只是构成存封的铂族元素资源，对整个杂岩体资源没有重要的贡献。

关键词：铂族元素矿床布什维尔德杂岩铬铁矿

Aneuploidy in stem cells

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World Journal of Stem Cells 2016年第6期8卷 216-222页

作者： Jorge Garcia-martinez Bjorn Bakker Klaske m Schukken judith E Simon Floris Foijer European Research Institute for the Biology of Ageing University of GroningenUniversity Medical Center Groningen

Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells(IPSCs) from somatic cells has brought this promise steps closer to reality. However,as somatic cells might have accumulated various chromosomal abnormalities,including aneuploidies throughout their lives,the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated,or worse,become at risk of adopting a malignant fate. In this review,we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore,we review the differences between how somatic cells and stem cells respond to aneuploidy.

关键词： Chromosomal instability Aneuploidy Embryonic stem cells Induced pluripotent stem cells mesenchymal stem cells

Physical Activation of Elderly and the Decrease of Falling Risk

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Health 2014年第11期6卷 1116-1123页

作者： martha Ornelas Verónica Benavides Juan F. Aguirre Gabriel Gastélum judith m. Rodríguez-Villalobos Faculty of Physical Culture Sciences Autonomous University of Chihuahua Chihuahua México

A Physical Activation Program was designed and implemented with a particular emphasis in recovering of motor independence, and in an indirect manner;the increase of activities was carried out in a social context in such a way that it allowed isolated elderly to develop their ability to perform daily activities diminishing the burden on their caregivers. 30 people were randomly selected: 15 subjects in the experimental group and 15 in the control group;7 women and 8 men each group. Subjects aged between 60 - 84 years with a mean age of 78 years and a standard deviation of 6.5 were applied in a three-month Physical Activation Program with a 45-min daily sessions. Results obtained showed that physical activity in elderly, systematically improved their amplitude and joint mobility which impact directly and indirectly their quality of life, reducing their risk of falling.

关键词： Physical Activation Older Adult Risk of Falling Joint mobility

Granisetron Transdermal Patch for Treatment of Nausea in Patients Undergoing Cisplatin Based Chemotherapy for Cervical Cancer

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Journal of Cancer Therapy 2012年第6期3卷 1159-1163页

作者： Helen Dunnington Rodney Hunter michael Frumovitz judith Smith College of Pharmacy Texas Southern University Houston USA University of Texas m. D. Anderson Cancer Center Houston USA. University of Texas medical School at Houston Houston USA University of Texas medical School at Houston Houston USA&College of Pharmacy Texas Southern University Houston USA&University of Texas M. D. Anderson Cancer Center Houston USA

Objective: The purpose of this study was to define the incidence of chemotherapy-induced nausea and vomiting (CINV) in newly diagnosed cervical cancer patients receiving cisplatin and radiation treatment;and to determine if the granisetron transdermal patch (Sancuso?) would be appropriate to recommend as part of standard antiemetic regimen for the cisplatin radiation chemotherapy order set. methods: This is a retrospective case-controlled study of cervical cancer patients receiving cisplatin chemotherapy with radiation (cisXRT);comparing patients receiving the granisetron transdermal patch to matched patients receiving oral 5HT3 blockers. All patients prescribed cisXRT between September 15th 2008 and November 30, 2011 were identified using pharmacy dispensing records. Patients were included if they received at least a partial dose of cisXRT and Sancuso? patch as standard antiemetic prophylaxis prior to cisXRT for cervical cancer treatment. Exclusion criteria included concomitant investigational agents, biotherapy and/or chemotherapy agents;prior chemotherapy;or incomplete or restricted medical records. Patients will be matched based on age. Patients were matched 3:1 (oral:patch). A total of 404 patients that received and completed cisXRT were identified utilizing an existing de-identified database from previous study were reviewed to evaluate parameters of interest. Results: A total of 285 patients’ medication records were reviewed for Sancuso? use, and 47 were identified. Of these 47 charts only five patient cases met eligibility criteria to be included in the study. All five patients that received the granisetron patch had at least three known risk factors for nausea. The nausea/vomiting in these patients did not worsen after receiving the Sancuso? patch, and four out of five had subjective improvement. CINV was unrelated to changes in laboratory values or incidence of other toxicity and was not dose-related. Conclusions: While no definitive conclusions could be d

关键词： Granisetron Nausea Vomiting Cisplatin Radiation

Epstein Barr virus-positive mucocutaneous ulcer of thecolon associated Hodgkin lymphoma in Crohn＇s disease

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World Journal of Gastroenterology 2015年第19期21卷 6072-6076页

作者： Neil R moran Bradley Webster Kenneth m Lee judith Trotman YiuLam Kwan John Napoli Rupert W Leong Neil R moran Rupert gW Leong Gastroenterology and Liver Services Concord Repatriation General Hospital Sydney NSW 2137 Australia.

Epstein Barr virus （EBV） positive mucocutaneous ulcers（EBVmCU） form part of a spectrum of EBV-associatedlymphoproliferative disease. They have been reportedin the setting of immunosenescence and iatrogenicimmunosuppression, affecting the oropharyngeal mucosa,skin and gastrointestinal tract （GIT）. Case reports andseries to date suggest a benign natural history respondingto conservative management, particularly in the GIT. Wereport an unusual case of EBVmCU in the colon, arisingin the setting of immunosuppression in the treatment ofCrohn＇s disease, with progression to Hodgkin lymphoma18 mo after cessation of infliximab. The patient presentedwith multiple areas of segmental colonic ulceration,histologically showing a polymorphous infiltrate withEBV positive Reed-Sternberg-like cells. A diagnosisof EBVmCU was made. The ulcers failed to regressupon cessation of infliximab and methotrexate for 18mo. Following commencement of prednisolone for herCrohn＇s disease, the patient developed widespreadHodgkin lymphoma which ultimately presented as alife-threatening lower GIT bleed requiring emergencycolectomy. This is the first report of progression ofEBVmCU to Hodgkin lymphoma, in the setting of ongoingiatrogenic immunosuppression and inflammatory boweldisease.

关键词： Epstein Barr virus mucocutaneous ulcer Hodgkin lymphoma Inflammatory bowel disease Crohn's disease

Antiradical Activity and Ferric Reducing Antioxidant Power of Pleurotus pulmonarius, Pleurotus floridanusand Pleurotus sajor-cajuFormulations Extracts in Vitro

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Food and Nutrition Sciences 2019年第10期10卷 1202-1211页

作者： Etoundi O.C.Blanche Kayo T.C.Valère mbang m.A.judith Ngono N.A.Rosalie Department of Biochemistry Faculty of ScienceUniversity of DoualaDoualaCameroon

Edible mushrooms, known for many years and considered as functional foods, contain a wide variety of biomolecules with nutritional and medicinal properties. Pleurotus species, especially Pleurotus pulmonarius, Pleurotus floridanus and Pleurotus sajor-caju are the most commonly consumed in Cameroon. The present work aims to study the “in vitro” antiradical activity and ferric reducing antioxidant power of extracts of formulations of these three species. mushrooms were harvested in two mycicultures from Cameroon, then dried and crushed finely to obtain powders. In well-defined proportions, ten different formulations were made and their aqueous, ethanol and hydroethanol extracts prepared. These were used to determine total phenolic content by using Folin-Ciocalteu reagent method, the antioxidant activity determined by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activity and ferric-reducing antioxidant power (FRAP) assays, with vitamin C (ascorbic acid) as standard. The results obtained from the ten formulations, including thirty extracts, showed that all the extracts had quite significant ferric reducing power at C = 1 mg/ml, (7.35 - 26.02 mg EAA/g). They also had good percentages of DPPH radical inhibition at C = 25 mg/ml (60.40% - 77.72%) and a significant polyphenol content at C = 100 mg/ml (13.73 - 21.15 mg CE/g). The aqueous extracts had the best activities compared to the standard. In addition, a strong positive linear correlation exists between polyphenol content and the scavenging property (R2 = 0.9063;p = 0.0003) also with the ferric reducing test (R2 = 0.9253;p = 0.0001);suggesting the responsibility of these compounds for these activities. This study suggests that these mushrooms may be used as a natural source of potential antioxidants for food supplements and their consumption is strongly recommended for their beneficial effects on health through, the protection of the human body against the oxidative damage involved in the occurrence of many c

关键词： Scavenging Activity Ferric Reducing Antioxidant Power Edible mushrooms

应用特制薄层层析法避免类脂干扰分离药物的简易方法

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药学实践与服务 1983年第2期 53-55页

作者： judith m.Bonicamp 王洁之

薄层层析法现已广泛地用以检测生物体液中的药物。此法在分析尿液标本时是成功的,但是在分析血样时却受到一些因素的限制。许多药物的血清治疗浓度都低于1μg/ml,而在层析板上每一斑点检测限度需1μg 以上的药物,因此欲达到薄层检测浓... 详细信息

薄层层析法现已广泛地用以检测生物体液中的药物。此法在分析尿液标本时是成功的,但是在分析血样时却受到一些因素的限制。许多药物的血清治疗浓度都低于1μg/ml,而在层析板上每一斑点检测限度需1μg 以上的药物,因此欲达到薄层检测浓度就需较多血样。除了这个因素以外,类脂的干扰也是一个因素。某些药物血清浓度高,本可以很快用薄层层析

关键词：类脂薄层层析法药物

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如何俘获人心

中外管理 2010年第10期 56-57页

作者： judith m．Bardwick[美] 之澜（编译）

事实上,薪酬福利在提高敬业度、忠诚度上虽非惟一却仍然是重要的手段,但传统的做法已经收效甚微。

关键词：人心俘获薪酬福利敬业度忠诚度

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Open Journal of Preventive medicine 2012年第3期2卷 332-338页

作者： Wendy L. Ward judith L. Weber Jeff Gossett Pippa Simpson margaret L. Bogle James m. Robbins Agricultural Research Service USDA Little Rock AR Department of Pediatrics University of Arkansas for Medical Sciences College of Medicine and Arkansas Children’s Hospital Little Rock AR Little Rock AR USA

Objective: Adults and children in rural settings are at greater risk for overweight and obesity than those in urban settings. multiple studies have suggested that quality of life is lower for obese individuals. This study addresses the association of obesity with health-related Quality of Life (QOL) among youth in the rural mississippi Delta. methods: QOL data on children aged 3 - 17 years using the PedsQL were collected as part of a cross-sectional telephone survey in the Delta. Weight was grouped by AAP categorizations as underweight, normal, overweight (85 - 95th BmI percentile), obese (95 - 97th percentile), and extremely obese (> 97th percentile). Results: 437 youth participated. multiple linear regression models were used to predict PedsQL component scores. Results showed main effects for age (p = 0.006), race (p mI group (p = 0.049) on psychosocial QOL. Older children ages 9 - 17, white and black children, and obese or extremely obese children scored lower on psychosocial QOL than younger children, other race, and non- obese. A strong age by weight group interaction (p = 0.014) showed that obesity and extreme obesity was associated with lower scores on psychosocial QOL only for older children ages 12 - 17. Conclusions: Investigating the QOL in this rural community where the majority of adults and children are obese aids in our understanding the relationship between sociocultural factors and HRQOL. In the context of an obese majority obesity and extreme obesity remain important contributions to reduced psychosocial (emotional, social, school performance) quality of life for adolescents but not for younger children).

关键词： Pediatric Obesity Overweight Quality of Life Rural Health