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Systematic review of mini-implant displacement under orthodontic loading

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International Journal of Oral Science 2014年第1期6卷 1-6页

作者： Manuel Nienkemper Jrg Handschel Dieter Drescher Department of Orthodontics Heinrich-Heine-University Department of Oral and Maxillofacial Surgery Heinrich-Heine-University

A growing number of studies have reported that mini-implants do not remain in exactly the same position during treatment, although they remain stable. The aim of this review was to collect data regarding primary displacement immediately straight after loading and secondary displacement over time. A systematic review was performed to investigate primary and secondary displacement. The amount and type of displacement were recorded. A total of 27 studies were included. Sixteen in vitro studies or studies using finite element analysis addressed primary displacement, and nine clinical studies and two animal studies addressed secondary displacement. Significant primary displacement was detected （6.4-24.4 μm） for relevant orthodontic forces （0.5-2.5 N）. The mean secondary displacement ranged from 0 to 2.7 mm for entire mini-implants, The maximum values for each clinical study ranged from 1.0 to 4.1 mm for the head, 1.0 to 1.5 for the body and 1,0 to 1.92 mm for the tail part. The most frequent type of movement was controlled tipping or bodily movement. Primary displacement did not reach a clinically significant level. However, clinicians can expect relevant secondary displacement in the direction of force. Consequently, decentralized insertion within the inter-radicular space, away from force direction, might be favourable. More evidence is needed to provide quantitative recommendations.

关键词： displacement migration mini-implant miniscrew orthodontics skeletal anchorage

NUMERICAL APPROXIMATION OF THE SMOLUCHOWSKI EQUATION USING RADIAL BASIS FUNCTIONS

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Journal of Computational Mathematics 2020年第1期38卷 176-194页

作者： Christiane Helzel Maximilian Schneiders Institut of Mathematics Heinrich-Heine-Universitat DusseldorfGermany formerly Institut of Mathematics Heinrich-Heine-Universitat DusseldorfGermany

The goal of this paper is to present a numerical method for the Smoluchowski equation,a drift-diffusion equation on the sphere,arising in the modelling of particle *** numerical method uses radial basis functions(RBF).This is a relatively new approach,which has recently mainly been used for geophysical *** a simplified model problem we compare the RBF approach with a spectral method,*** standard approach used in related physical *** comparison as well as our other accuracy studies show that RBF methods are an attractive alternative for these kind of models.

关键词： Smoluchowski equation Spectral method Radial basis function method

Intrahepatic cholestasis without jaundice

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Hepatobiliary & Pancreatic Diseases International 2009年第1期8卷 103-105页

作者： Thomas Namdar Andreas Raffel Stefan Andreas Topp Jan Schulte am Esch Günther Fürst Wolfram Trudo Knoefel Claus Ferdinand Eisenberger Department of General Visceral and Pediatric Surgery Heinrich-Heine University Institute of Diagnostic Radiology Heinrich-Heine University

BACKGROUND:Cholangiocarcinoma(CC),the most common biliary tract malignancy,is frequently seen in advanced unresectable stages and is typically localized *** diagnosis is unusual because of nonspecific *** jaundice is usually the first sign of tumor. METHOD:We present a patient with a CC(Klatskin tumor) with a complete biliary drainage by an aberrant bile duct without jaundice. RESULTS:A 67-year-old woman presented with persisting elevation of liver *** tests showed a Klatskin tumor typeⅡ.A curative right hepatic trisegmentectomy was performed after liver volume augmentation by preoperative vein embolization. CONCLUSIONS:A direct drainage of the right posterior bile duct into the common bile duct as an aberrant hepatic duct is a rare variation and is present in less than 5%of the *** case of persistently perturbed liver function tests,an aberrant bile duct can cover up severe intrahepatic cholestasis and even obscure the diagnosis of a Klatskin *** to now it has not been described in the literature.

关键词： Klatskin tumor hyperbilirubinemia cholangiocarcinoma

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano Sergei A.Kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Extrahepatic intraductal ectopic hepatocellular carcinoma:bile duct filling defect

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Hepatobiliary & Pancreatic Diseases International 2009年第6期8卷 650-652页

作者： Moritz Schmelzle Hanno Matthaei Nadja Lehwald Andreas Raffel Roy Y.Tustas Natalia Pomjanski Petra Reinecke Marcus Schmitt Jan Schulte am Esch Wolfram T.Knoefel Claus F.Eisenberger Department of General Visceral and Pediatric Surgery Heinrich-Heine-University Düsseldorf Institute of Cytopathology heinrich-heine-University Düsseldorf Institute of Pathology heinrich-heine-University Düsseldorf Department of Gastroenterology Hepatology and Infectious Diseases Heinrich-Heine-University Düsseldorf

BACKGROUND:Obstructive jaundice caused by an intraductal hepatocellular carcinoma is a rare initial *** report a rare case of an extrahepatic icteric type hepatocellular ***:A 75-year-old patient was admitted to our hospital because of obstructive jaundice 3 months after resection of multilocular hepatocellular carcinoma.A postoperative bile leakage was treated by placement of a decompressing stent in the common bile *** retrograde choledochoscopy showed extended blood clots filling the bile duct system and computed tomography revealed a local swelling in the common extrahepatic bile *** level of alpha-fetoprotein(AFP)was only slightly elevated but that of CA19-9 was dramatically *** showed an intraductal filling defect typical of a cholangiocellular ***:Bile duct brushing cytology showed no cholangiocellular carcinoma but hepatocellular carcinoma cells in the extrahepatic bile *** extrahepatic bile duct resection was *** examination confirmed the diagnosis of extrahepatic intraductal growth of hepatocellular ***:Ectopic hepatocellular carcinoma is a rare but important differentially diagnosed of extrahepatic bile duct filling defect.

关键词： hepatocellular carcinoma cholangiocellular carcinoma bile duct obstructive jaundice

Synthesis and electronic properties of expanded 5-(hetero)arylthien-2-yl substituted 3-ethynyl quinoxalines with AIE characteristics

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Science China Chemistry 2018年第8期61卷 909-924页

作者： Franziska K.Merkt Thomas J.J.Müller Institute of Organic Chemistry and Macromolecular Chemistry Heinrich Heine University Düsseldorf

Expanded 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes with variable substitution pattern on the peripheral thiophene ring were synthesized in moderate to very good yields by Suzuki and Buchwald-Hartwig coupling of the corresponding brominated 3-ethynyl quinoxalines. Dumbbell-shaped bis(thienyl 3-ethynyl quinoxalines) are also accessible by the Suzuki protocol. The photophysical properties were investigated by UV and fluorescence spectroscopy. Most of the obtained compounds display fluorescence in solution and some of them also in the solid state. Additionally, tuning of the emission color of the quinoxaline based chromophores can be conveniently accomplished by the remote substituent group. The determined absorption and emission maximum as well as the Stokes shifts strongly correlate with Hammett σp+parameters. Besides,photophysical properties of selected derivatives in the solid state, biphasic solutions, and PMMA films, along with their relationships, are comparatively investigated. Moreover, two 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes are aggregation induced emission(AIE) chromophores indicated by restriction of molecular motions. A covalently restricted 3-ethynyl quinoxaline supports that the inhibition of molecular rotation is responsible for the significant enhancement of fluorescence in acetonitrile/water mixtures.

关键词： absorption aggregation induced emission cross-coupling fluorescence heterocycles palladium

Effects of sleep bruxism on functional and occlusal parameters:a prospective controlled investigation

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International Journal of Oral Science 2012年第3期4卷 141-145页

作者： Michelle Alicia Ommerborn Maria Giraki Christine Schneider Lars Michael Fuck Jrg Handschel Matthias Franz Wolfgang Hans-Michael Raab Ralf Schfer Department of Operative Dentistry Periodonticsand EndodonticsHeinrich-Heine-University Institute of Psychosomatic Medicine and Psychotherapy Heinrich-Heine-University Private Practice in Orthodontics Konrad-Adenauer-Platz 4LangenfeldGermany Department of Cranio-and Maxillofacial Surgery Heinrich-Heine-University

This study was conducted to verify the results of a preceding retrospective pilot study by means of a prospective controlled investigation including a larger sample size. Therefore, the aim of this clinical investigation was to analyze the relationship between sleep bruxism and several functional and occlusal parameters. The null hypothesis of this study was that there would be no differences among sleep bruxism subjects and non-sleep bruxism controls regarding several functional and occlusal parameters. Fifty-eight sleep bruxism subjects and 31 controls participated in this study. The diagnosis sleep bruxism was based on clinical criteria of the American Academy of Sleep Medicine. Sixteen functional and occlusal parameters were recorded clinically or from dental study casts. Similar to the recently published retrospective pilot study, with a mean slide of 0.77 mm （s.d., 0.69 mm） in the sleep bruxism group and a mean slide of 0.4 mm （s.d., 0.57 mm） in the control group, the evaluation of the mean comparison between the two groups demonstrated a larger slide from centric occlusion to maximum intercuspation in sleep bruxism subjects （Mann-Whitney U-test; P=O.O08）. However, following Bonferroni adjustment, none of the 16 occlusal and functional variables differed significantly between the sleep bruxism subjects and the non-sleep bruxism controls. The present study shows that the occlusal and functional parameters evaluated do not differ between sleep bruxism subjects and non-sleep bruxism subjects. However, as the literature reveals a possible association between bruxism and certain subgroups of temporomandibular disorders, it appears advisable to incorporate the individual adaptive caoacitv of the stomatognathic svstem into future investigations.

关键词： dental occlusion functional parameters prospective study sleep bruxism

Heterogeneous populations of neural stem cells contribute to myelin repair

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Neural Regeneration Research 2017年第4期12卷 509-517页

作者： Rainer Akkermann Felix Beyer Patrick Küry Neuroregeneration Laboratory Department of NeurologyMedical FacultyHeinrich-Heine-University

As ingenious as nature＇s invention of myelin sheaths within the mammalian nervous system is, as fatal can be damage to this specialized lipid structure. Long-term loss of electrical insulation and of further supportive functions myelin provides to axons, as seen in demyelinating diseases such as multiple sclerosis （MS）, leads to neurodegeneration and results in progressive disabilities. Multiple lines of evidence have demon-strated the increasing inability of oligodendrocyte precursor cells （OPCs） to replace lost oligodendrocytes （OLs） in order to restore lost myelin. Much research has been dedicated to reveal potential reasons for this regeneration deficit but despite promising approaches no remyelination-promoting drugs have successfully been developed yet. In addition to OPCs neural stem cells of the adult central nervous system also hold a high potential to generate myelinating OLs. There are at least two neural stem cell niches in the brain, the subventricular zone lining the lateral ventricles and the subgranular zone of the dentate gyrus, and an additional source of neural stem cells has been located in the central canal of the spinal cord. While a substantial body of literature has described their neurogenic capacity, still little is known about the oligodendrogenic potential of these cells, even if some animal studies have provided proof of their contribution to remyelination. In this review, we summarize and discuss these studies, taking into account the different niches, the heterogeneity within and between stem cell niches and present current strategies of how to promote stem cell-mediated myelin repair.

关键词： heterogeneity oligodendrocyte neuroregeneration multiple sclerosis inhibitors intracellular proteinlocalization adult neural stem cell niche remyelination

Human endogenous retroviruses: ammunition for myeloid cells in neurodegenerative diseases?

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Neural Regeneration Research 2020年第6期15卷 1043-1044页

作者： Joel Gruchot David Kremer Patrick Küry Department of Neurology NeuroregenerationMedical FacultyHeinrich-Heine-University

Activation of myeloid cells by human endogenous retroviral entities:While the exact causes of neurological diseases such as multiple sclerosis(MS)or amyotrophic lateral sclerosis(ALS)are still elusive,there is evidence of a new category of pathogenic elements called human endogenous retroviruses(HERVs)which seem to contribute to their evolution and progression by exerting inflammatory and degenerative effects(Kury et al.,2018).HERVs are ancient retroviral elements which account for up to 8%of the human genome and it is known that environmental factors can trigger their(re-)expression(Kury et al.,2018).The resulting production of viral particles and/or proteins,especially from members of the HERV-W and HERV-K family,is strongly correlated with the onset and progression of neurological diseases,such as MS and ALS(Kury et al.,2018).

关键词： endogenous diseases al.