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Acta Geologica Sinica(English Edition) 2012年第2期86卷 304-312页

作者： XING Lida Phil R.BELL je.aldd.harris Philip J.CURRIE Department of Biological Sciences University of Alberta11455 Saskatchewan DriveEdmontonAlberta T6G 2E9Canada Key Laboratory of Evolutionary Systematics of Vertebrates Chinese Academy of SciencesPO Box 643100044 BeijingChina Pipestone Creek Dinosaur Initiative ClairmontAlberta TOH OWOCanada. Physical Sciences Department Dixie State College225 South 700 EastSt.GeorgeUtah 84770USA

Three-dimensional tracks provide unique insights into the locomotor mechanics of their track makers. An isolated, large hadrosauriform print attributable to Caririchnium lotus from the ＂mid＂-Cretaceous Lotus track site （Jiaguan Formation） in China permits reconstruction of the footfall, weight-bearing, and kick-off phases of the step cycle. Large-scale modifications of the pes during the step cycle indicate C. lotus trackmakers were capable of locomotory modifications in response to substrate consistency beyond the ＂expected＂ shift between bipedal and quadrupedal postures. An unusual curvature to the trace of one of the outer digits indicates substantial transverse mobility. The remaining digits demonstrate lesser degrees of transverse movement accompanied by extension of the digits during footfall. The absence of overprinted scale-scratch marks and toe drags are consistent with a vertical kick-off of the pes and concomitant flexion of the digits. This track suggests that pedal mobility in C. lotus track makers was greater than previously suspected and has implications for reconstructions of hadrosauriform locomotion.

关键词： hadrosauriform locomotion footprints Cretaceous step cycle

TRANSIMIDIZATION IN THERMOPLASTIC POLYIMIDES

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Chinese Journal of Polymer Science 1999年第2期17卷 171-184页

作者： Yoan Kim Doyun Kim Frank W.harris Stephen Z.D.Cheng Maurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USA

In order to improve the processibility in thermoplastic polyimides, a new method, termed the'reactive plasticizer' approach, has been proposed. This method uses a small amount (5～15 mol%) of a lessactivated, weak nucleophilic diamine co-monomer as a 'reactive plasticizer' to obtain copolyimide resinswhich possess relatively low viscosity at low temperatures and can be readily processed through the autoclavecycle at low pressures. During a high temperature treatment, the reactive plasticizers join the reaction to formhigh molecular weight copolyimides, and the preferred material properties are thus achieved. The mosteffective reactive plasticizer is aromatic heterocyclic diamines, such as 2, 6-diaminopyridine diamine (DAP),and the transimidization involved with a reactive plasticizer has been proposed to play a major role for thesuccess of this approach. In order to understand the transimidization mechanism, three steps have been takenin this research: first, a copolyimide system of 50% of DAP and 50% 1, 4 -bis [4-aminophenoxy] benzenediamine (DODA) with 100% of 2, 2'-bis[4-(3, 4-dicarboxyphenoxy)phenyl] propane dianhydride (Ultem^(R)DA) is prepared. Second, several specifically designed polyimide mixture systems were used, and they consistof two homopolyimides: one is Ultem^(R) DA-DODA, and the other is Ultem^(R) DA-DAP. The third step is toinvestigate two mixture systems in which Ultem^(R) DA-DODA is mixed with DAP monomer solution andUltem^(R) DA-DAP is mixed with DODA monomer solution. For all systems, with increasing degree oftransimidization upon heat-treatment, the chain structures of the mixtures and their thermal and dynamicmechanical transition behaviors are investigated via one-dimensional and two-dimensional nuclear magneticresonance, differential scanning calorimetry, and dynamic mechanical analysis experiments. Experimentalresults indicate that in the mixture of two homopolyimides, transimidization takes place much moreefficiently in solution than in th

关键词： Transmidization Thermoplastic polyimides

A New Fossil Termite (Isoptera,Stolotermitidae,Stolotermes) from the Early Miocene of Otago,New Zealand

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 705-709页

作者： Uwe KAULFUSS Anthony C.harris Daphne E.LEE Department of Geology University of OtagoPO Box 56Dunedin 9054New Zealand Otago Museum PO Box 6202Dunedin 9059New Zealand

The forewing of a termite from Early Miocene lake sediments in Otago, southern New Zealand is figured and described. It exhibits the generic characters of the damp-wood termite Stolotermes Hagen, but differs from forewings of the known species in size and venation pattern and is described as Stolotermes kupe sp. nov. S. kupe represents the first confident record of fossil Stolotermitidae and extends the fossil record of the family back to the Early Miocene. It also is the first direct evidence of fossil Isoptera from New Zealand, though silicified termite faecal pellets, referable to Kalotermes brauni, have been previously described. S. kupe indicates that Stolotermitidae has been present in the Australasian region since at least the Early Miocene.

关键词： Early Miocene fossil termite Isoptera Stolotermes new species Otago Fouiden Maar Gondwana

In vitro and in vivo application of RNA interference for targeting genes involved in peritrophic matrix synthesis in a lepidopteran system

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Insect Science 2013年第1期20卷 92-100页

作者： Umut Toprak Doug Baldwin Martin Erlandson Cedric Gillott Stephanie harris Dwayne D. Hegedus Agriculture and Agri-Food Canada Ottawa Ontario Canada Department of Biology University of Saskatchewan Canada Department of Plant Protection Faculty of Agriculture University of Ankara Turkey Department of Food and Bioproduct Sciences University of Saskatchewan Saskatoon SK Canada

The midgut of most insects is lined with a semipermeable acellular tube, the peritrophic matrix （PM）, composed of chitin and proteins. Although various genes encoding PM proteins have been characterized, our understanding of their roles in PM structure and function is very limited. One promising approach for obtaining functional information is RNA interference, which has been used to reduce the levels of specific mRNAs using double-stranded RNAs administered to larvae by either injection or feeding. Although this method is well documented in dipterans and coleopterans, reports of its success in lepidopterans are varied. In the current study, the silencing midgut genes encoding PM proteins （insect intestinal mucin 1, insect intestinal mucin 4, PM protein 1） and the chitin biosynthetic or modifying enzymes （chitin synthase-B and chitin deacetylase 1） in a noctuid lepidopteran, Mamestra configurata, was examined in vitro and in vivo. In vitro studies in primary midgut epithelial cell preparations revealed an acute and rapid silencing （by 24 h） for the gene encoding chitin deacetylase 1 and a slower rate of silencing （by 72 h） for the gene encoding PM protein 1. Genes encoding insect intestinal mucins were slightly silenced by 72 h, whereas no silencing was detected for the gene encoding chitin synthase-B. In vivo experiments focused on chitin deacetylase 1, as the gene was silenced to the greatest extent in vitro. Continuous feeding of neonates and fourth instar larvae with double-stranded RNA resulted in silencing of chitin deacetylase 1 by 24 and 36 h, respectively. Feeding a single dose to neonates also resulted in silencing by 24 h. The current study demonstrates that genes encoding PM proteins can be silenced and outlines conditions for RNA interference by per os feeding in lepidopterans.

关键词： chitin deacetylase chitin synthase-B lepidoptera peritrophic matrix,peritrophin RNA interference

Piperine,an active ingredient of black pepper attenuates acetaminophen-induced hepatotoxicity in mice

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Asian Pacific Journal of Tropical Medicine 2010年第12期3卷 971-976页

作者： Evan Prince Sabina Annie Deborah harris Souriyan Deborah Jackline Mahaboob Khan Rasool School of Biological Sciences and Technology VIT University Vellore - 632 014Tamil NaduIndia

Objective:To explore the hepatoprotective and antioxidant effects of piperine against acetaminophen-induced hepatotoxicity in ***:In mice,hepatotoxicity was induced by a single dose of acetaminophen(900 mg/kg b.w.i.p.).Piperine(25 mg/kg b.w.i.p.) and standard drug silymarin(25 mg/kg b.w.i.p.) were given to mice,30 min after the single injection of *** 4 h,the mice were *** of liver marker enzymes [(aspartate transaminase(AST),alanine transaminase(ALT),and alkaline phosphatase(ALP)]and inflammatory mediator tumour necrosis factor-alpha(TNF-α) were estimated in serum,while lipid peroxidation and antioxidant status(superoxide dismutase,catalase,glutathione peroxidase, glutathione reductase,glutathione-s-transferase and glutathione) were determined in liver homogenate of control and experimental ***:Acetaminophen induction(900 mg/kg b.w.i.p.) significantly increased the levels of liver marker enzymes,TNF-α,and lipid peroxidation,and caused the depletion of antioxidant *** and silymarin treatment to acetaminophen challenged mice resulted in decreased liver marker enzymes activity,TNF-αand lipid peroxidation levels with increase in antioxidant ***:The results clearly demonstrate that piperine shows promising hepatoprotective effect as comparable to standard drug silymarin.

关键词： Pipeline Hepatoprotective Antioxidant enzymes Lipid peroxidation TNF-α

jejunal diverticulosis is not always a silent spectator:A report of 4 cases and review of the literature

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World Journal of Gastroenterology 2008年第38期14卷 5916-5919页

作者： Vishal Arun Patel Helen jefferis Ben Spiegelberg Quamar Iqbal Ashish Prabhudesai Simon harris Department of Colorectal Surgery Hillingdon Hospital UxbridgeMiddlesex UB8 3NN United Kingdom

jejunal diverticulosis (JD) is a rare clinical entity. The potential complications of this condition are discussed here through a series of cases presented to our centre. A retrospective analysis of four cases, which were diagnosed and treated, was performed. These included two cases of gastrointestinal haemorrhage, one case of perforation and one case of enterolith obstruction. All of these cases were secondary to jejunal diverticulosis and treated surgically. This was accompanied by a literature search to identify the different modalities for diagnosis and treatment of this condition. JD is rare and may lead to a diagnostic delay. Awareness of the wide spectrum of potential complications can prevent this delay.

关键词： jejunum Diverticulosis Gastrointestinal Haemorrhage Perforation Enterolith Obstruction

Single incision laparoscopic myomectomy in pregnancy

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Gynecology and Obstetrics Clinical Medicine 2022年第2期2卷 96-99页

作者： Brooke Thigpen Tara harris Sowmya Sunkara Xiaoming Guan Department of Obstetrics and Gynecology Baylor College of MedicineHoustonTXUSA

The prevalence of fibroids in pregnancy ranges from 2%to 10%.About 10%of these fibroids lead to complications in pregnancy including pain,intrauterine growth restriction,morbidly adherent placentation,placental abruption,dystocia,and postpartum hemorrhage.1 Pain is the most common complication of fibroids during pregnancy.2 Causes of pain include increased pressure on the fibroid itself,torsion of a pedunculated fibroid,and degeneration due to rapid fibroid growth.2 Pain can first be managed conservatively with rest,hydration,and analgesics;however,if pain is refractory to conservative management,surgical management with myomectomy may be indicated.3 Spyropoulou K et al.4 performed a review of the literature regarding myomectomy in *** review found that majority of myomectomies in pregnancy were performed via laparotomy with overall favorable pregnancy outcomes and few complications,concluding that myomectomy in pregnancy is safe in cases not responding to conservative management.

关键词： conservative torsion hydration

Adult immunization improvement in an underserved family medicine practice

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Family Medicine and Community Health 2015年第2期3卷 2-7页

作者： Mohamad Sidani Jaden harris Roger J.Zoorob Department of Family and Community Medicine Baylor College of MedicineHoustonTXUSA

Objective:Vaccines prevent many cases of infectious disease,yet immunization campaigns are hindered by various *** work presents the results of a quality improvement project addressing barriers to vaccine compliance in an underserved teaching practice by reducing missed opportunities and increasing provider and patient compliance rates for pneumococcal,Tdap,influenza,and zoster vaccines in ***:The study intervention aimed to address patient knowledge,provider knowledge and skills,proactive care coordination,and outreach and counselling of high-risk ***-gate patient data from intervention at year-end were compared to the prior *** targets were as follows:improved vaccination rates by one-half of the difference between baseline and Healthy People 2020 goals;reduced patient refusals by 10%;and reduced missed opportunities by 50%.Results:All of the vaccination rates improved,but with mixed results regarding the target *** rates of vaccine refusal were mixed in terms of the direction of the change,the significance,and achieving *** opportunities all improved,but the significance was mixed and none reached ***:This project has helped to identify patient and provider knowledge of vacci-nation as a key to increasing compliance,and missed opportunities as the greatest challenge in achieving *** burden of documentation is significant on providers,and future work should focus on methods to improve the ease of *** outcomes and improvements were encouraging;however,it is clear that there remain challenges to reaching Healthy People 2020 goals within the study population and nationally.

关键词： Immunization vaccine practice improvement pneumococcal Tdap influenza zoster

铕(Ⅲ)离子与人血清脱铁转铁蛋白结合的紫外差光谱研究

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化学学报 1999年第5期57卷 503-509页

作者：杨斌盛 WesleyR.harris 山西大学分子科学研究所太原030006 Department

在pH7.4,温度为25℃的条件下,用紫外吸收差光谱进行了Eu^(3+)对人血清脱铁转铁蛋白的滴定.结果表明Eu^(3+)与人血清脱铁转铁蛋白结合后其差光谱在245nm和296nm处出现吸收峰,在245nm处,Eu^(3+)-脱铁转铁蛋白配合物的摩尔吸光系数是(2.2±... 详细信息

在pH7.4,温度为25℃的条件下,用紫外吸收差光谱进行了Eu^(3+)对人血清脱铁转铁蛋白的滴定.结果表明Eu^(3+)与人血清脱铁转铁蛋白结合后其差光谱在245nm和296nm处出现吸收峰,在245nm处,Eu^(3+)-脱铁转铁蛋白配合物的摩尔吸光系数是(2.2±0.1)×10~4cm^(-1)·mol^(-1)·dm^3,Eu^(3+)可占据脱铁转铁蛋白的2个金属离子结合部位,Eu^(3+)优先占据脱铁转铁蛋白的C端结合部位,条件平衡常数是logK_c=8.42±0.12,logK_N=6.03±***^(3+)与R_E^(3+)(R_E=Nd,Sm,Gd和Tb)间的线性自由能关系表明,稀土离子占据脱铁转铁蛋白的C端结合部位时受离子大小的影响.

关键词：人血清转铁蛋白脱铁转铁蛋白铕离子结合

Assimilation of carbonate country rock by the parent magma of the Panzhihua Fe-Ti-V deposit(SW China):Evidence from stable isotopes

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Geoscience Frontiers 2013年第5期4卷 547-554页

作者： Clement Ganino Chris harris Nicholas T.Arndt Stephen A.Prevec Geoffrey H.Howarth Geoazur Universite de Nice-Sophia AntipolisCNRS/IRD250 rue Albert Einstein 06560 ValbonneFrance Department of Geological Sciences University of Cape TownRondebosch 7701South Africa ISTerre Grenoble UniversitesCNRS/IRD BP 53 38041 Grenoble CEDEX 9France Department of Geology Rhodes UniversityGrahamstown 6140South Africa

The Panzhihua intrusion in southwest China is part of the Emeishan Large Igneous Province and host of a large Fe-Ti-V ore *** emplacement of the main intrusion,multiple generations of mafic dykes invaded carbonate wall rocks,producing a large contact *** measured the oxygen-isotope composition of the intrusions,their constituent minerals,and samples of the country *** and plagioclase from Panzhihua intrusion haveδ18O values that are consistent with magmatic equilibrium, and formed from magmas withδ18O values that were 1-2‰higher than expected in a mantle-derived *** unmetamorphosed country rock has highδ18O values,ranging from 13.2‰（sandstone） to 24.6-28.6‰（dolomite）.The skarns and marbles from the aureole have lowerδ18O andδ13C values than their protolith suggesting interaction with fluids that were in exchange equilibrium with the adjacent mafic magmas and especially the numerous mafic dykes that intruded the *** would explain the alteration ofδ18O of the dykes which have significantly higher values than expected for a mantle-derived *** on the exactδ18O values assumed for the magma and contaminant, the amount of assimilation required to produce the elevatedδ18O value of the Panzhihua intrusion was between 8 and 13.7 wt.%,assuming simple *** exact mechanism of contamination is unclear but may involve a combination of assimilation of bulk country rock,mixing with a melt of the country rock and exchange with CO2-rich fluid derived from decarbonation of the marls and *** mechanisms,particularly the latter,were probably involved in the formation of the Fe-Ti-V ores.

关键词： Panzhihua Stable isotopes Carbonates Assimilation Contamination