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Explaining the “Pulse of Protoplasm”: The search for molecular mechanisms of protoplasmic streaming

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Journal of Integrative Plant Biology 2015年第1期57卷 14-22页

作者： michael R.dietrich Department of Biological Sciences Dartmouth College

Explanations for protoplasmic streaming began with appeals to contraction in the eighteenth century and ended with appeals to contraction in the twentieth. During the intervening years, biologists proposed a diverse array of mechanisms for streaming motions. This paper focuses on the re-emergence of contraction among the molecular mecha-nisms proposed for protoplasmic streaming during the twentieth century. The revival of contraction is a result of a broader transition from colloidal chemistry to a macro- molecular approach to the chemistry of proteins, the recognition of the phenomena of shuttle streaming and the pulse of protoplasm, and the influential analogy between protoplasmic streaming and muscle contraction.

关键词： Actin cytoplasmic streaming history of cell biology protoplasm

Intraoperative Findings and Outcome of Latarjet Procedure

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Open Journal of Orthopedics 2018年第7期8卷 273-289页

作者： Andreas M. Riederer Thomas Lattmann Christoph Meier Heike A. Bischoff-Ferrari michael dietrich Patrick Grueninger Division of Traumatology/Orthopedics Department of Surgery Waid City Hospital Zurich Switzerland Division of Vascular Surgery Department of Surgery Cantonal Hospital Winterthur Winterthur Switzerland Division of Traumatology/Orthopedics Department of Surgery Cantonal Hospital Winterthur Winterthur Switzerland Department of Geriatrics and Aging Research University Hospital Zurich and University of Zurich Zurich Switzerland

Background: The purpose of this case series was to retrospectively compare radiological, clinical and functional outcomes and complications of diagnostic arthroscopy with open Latarjet procedures pre- and postoperatively within one year after surgery. Additionally we compared the pathologic findings during diagnostic arthroscopy with the radiological findings in preoperative contrast enhanced CT or MRI scans. Methods: Between 07/2009 and 11/2013 46 cases with unidirectional antero-inferior shoulder instability were enrolled, 4 cases were lost during the follow-up within one year postoperatively. Plain radiographs, contrast enhanced multislice studies, Instability Severity Index, Constant, Duplay and Rowe Scores were obtained preoperatively. Diagnostic arthroscopy was performed in all cases prior to open Latarjet procedure. At one year follow-up Constant, Duplay and Rowe Scores were obtained;position and consolidation of the coracoid transfer were assessed by conventional x-ray studies. Results: At one year follow-up a significant improvement of all scores was recorded (Constant Score 95.8 vs. 86.7;Duplay Score 93.7 vs. 25.2, Rowe Score 98.1 vs. 31.7, (p Conclusion: The Latarjet procedure is a reliable technique with very good clinical outcomes. Diagnostic arthroscopy is a valuable tool to detect HAGL- and IGHL-lesions and to visualize the engaging potential of Hill-Sachs-lesions. An additional arthroscopy may help to indicate a Latarjet procedure and to address concomitant pathologies. Level of evidence: Level IV, case series.

关键词： Shoulder Instability Shoulder Arthroscopy Latarjet Procedure HAGL Lesion Bankart Lesion Instability Severity Index Score Engaging Hill-Sachs Lesion

Distortions in focusing laser pulses due to spatio-temporal couplings: an analytic description

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High Power Laser Science and Engineering 2024年第3期 25-45页

作者： Klaus Steiniger Fabia dietrich Daniel Albach michael Bussmann Arie Irman Markus Loeser Richard Pausch Thomas Püschel Roland Sauerbrey Susanne Sch?bel Ulrich Schramm Mathias Siebold Karl Zeil Alexander Debus Helmholtz-Zentrum Dresden-Rossendorf Dresden Germany CASUS-Center for Advanced Systems Understanding G?rlitz Germany Technische Universit?t Dresden Dresden Germany

In ultra-short laser pulses, small changes in dispersion properties before the final focusing mirror can lead to severe pulse distortions around the focus and therefore to very different pulse properties at the point of laser±matter interaction,yielding unexpected interaction results. The mapping between far-and near-field laser properties intricately depends on the spatial and angular dispersion properties as well as the focal geometry. For a focused Gaussian laser pulse under the influence of angular, spatial and group-delay dispersion, we derive analytical expressions for its pulse-front tilt,duration and width from a fully analytic expression for its electric field in the time±space domain obtained with scalar diffraction theory. This expression is not only valid in and near the focus but also along the entire propagation distance from the focusing mirror to the focus. Expressions relating angular, spatial and group-delay dispersion before focusing at an off-axis parabola, where they are well measurable, to the respective values in the pulse’s focus are obtained by a ray tracing approach. Together, these formulas are used to show in example setups that the pulse-front tilts of lasers with small initial dispersion can become several tens of degrees larger in the vicinity of the focus while being small directly in the focus. The formulas derived here provide the analytical foundation for observations previously made in numerical experiments. By numerically simulating Gaussian pulse propagation and measuring properties of the pulse at distances several Rayleigh lengths off the focus, we verify the analytic expressions.

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Contrast-enhanced endoscopic ultrasound in discrimination between focal pancreatitis and pancreatic cancer

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World Journal of Gastroenterology 2006年第2期12卷 246-250页

作者： michael Hocke Ewald Schulze Peter Gottschalk Theodor Topalidis Christoph F dietrich Department of Internal Medicine Ⅱ Friedrich Schiller University JenaErlanger Allee 10107740 JenaGermany Department of Pathology Friedrich Schiller University JenaErlanger Allee 10107740 JenaGermany Cytologic Institute Doehrbruch 6230559 HannoverGermany Caritas Hospital Department of Internal Medicine ⅡUhlandstraBe 797980 Bad MergentheimGermany

AIM： To evaluate the contrast-enhanced endosonography as a method of differentiating inflammation from pancreatic carcinoma based on perfusion characteristics of microvessels. METHODS： In 86 patients with suspected chronic pancreatitis （age： 62± 12 years; sex： f/m 38/48）, pancreatic lesions were examined by conventional endo- scopic B-mode, power Doppler ultrasound and contrastenhanced power mode （Hitachi EUB 525, SonoVue, 2.4 mL, Bracco） using the following criteria for malignant lesions： no detectable vascularisation using conventional power Doppler scanning, irregular appearance of arterial vessels over a short distance using SonoVue contrastenhanced technique and no detectable venous vessels inside the lesion. A malignant lesion was assumed if all criteria were detectable [gold standard endoscopic ultrasound （EUS）-guided fine needle aspiration cytology, operation]. The criteria of chronic pancreatitis without neoplasia were defined as no detectable vascularisation before injection of SonoVue, regular appearance of vessels over a distance of at least 20 mm after injection of SonoVue and detection of arterial and venous vessels. RESULTS： The sensitivity and specifidty of conventional EUS were 73.2% and 83.3% respectively for pancreatic cancer. The sensitivity of contrast-enhanced EUS increased to 91.1% in 51 of 56 patients with malignant pancreatic lesion and the specificity increased to 93.3% in 28 of 30 patients with chronic inflammatory pancreatic ***： Contrast-enhanced endoscopic ultrasound improves the differentiation between chronic pancreatitis and pancreatic carcinoma.

关键词： Endoscopic ultrasound Contrast enhancer Chronic pancreatitis Pancreatic cancer

Identification of syndrome X using intravascular ultrasound imaging and Doppler flow mapping

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Chinese Medical Journal 2004年第4期117卷 521-527页

作者：钱菊英葛均波樊冰王齐兵陈灏珠 dietrich Baumgart michael Haude Raimund Erbel Department of Cardiology Zhongshan Hospital Department of Cardiology

Background The purpose of this study was to assess the morphological changes and physiological function of coronary arteries in patients presenting with chest pain but having normal coronary angiograms, using intravascular ultrasound imaging (IVUS) and intracoronary Doppler (ICD) flow measurements, in order to elucidate the mechanism of syndrome X. Methods A total of 126 patients [67 males, 59 females, mean age (53.1±13.0) years] who experienced chest pain but had normal coronary angiograms were included in this study. ICD flow measurements of the left anterior descending coronary artery (LAD) were performed using a Cardiometrics FloMap Ⅱ system. Coronary flow velocity reserve (CFVR) was defined as the ratio of the average peak velocity during hyperemia to that at baseline, induced by an intracoronary bolus injection of 18 μg adenosine. A 3.2F or 2.9F 30 MHz mechanical rotating ultrasound catheter (CVIS, Boston Scientific) or a 3.0F 20MHz electronic ultrasound catheter (Endosonics) was used for IVUS. Results The mean CFVR value of the LAD was 2.71±0.74. Reduction of CFVR (<3.0) was found in 82 of 126 (65.1%) patients. IVUS images of the LAD were available for 109 patients. Plaque formation was detected in 76/109 (69.7%) patients. Based on the presence or absence of plaque formation as well as the reduction or non-reduction of CFVR, patients were divided into four groups: Group Ⅰ (n=10), normal IVUS findings and normal CFVR; Group Ⅱ (n=23), normal IVUS findings with reduction in CFVR; Group Ⅲ (n=29), IVUS evidence of plaque formation but normal CFVR; and Group Ⅳ (n=47), IVUS evidence of plaque formation with reduction in CFVR. Conclusion This study shows the important clinical value of a combination of IVUS and ICD in diagnosing patients with angiographically normal coronary arteries. Only 10% of patients studied (Group Ⅰ) were found to be truly free of coronary disease, while 20% of patients (Group Ⅱ) would be diagnosed as suffering from syndrome X.

关键词： coronary angiography Doppler ultrasound syndrome X

Liver-specific gene expression in mesenchymal stem cells is induced by liver cells

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World Journal of Gastroenterology 2005年第29期11卷 4497-4504页

作者： Claudia Lange Philipp Bassler michael V. Lioznov Helge Bruns dietrich Kluth Axel R. Zander Henning C. Fiegel Center of Bone Marrow Transplantation University Hospital Hamburg-Eppendorf Martinistrasse 52 D-20246 Hamburg Germany Department of Pediatric Surgery University Hospital Hamburg-Eppendorf Martinistrasse 52 D-20246 Hamburg Germany

AIM： The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed a key role of growth factors for the induction of liver-specific genes in stern cell cultures. We investigated the potential of rat mesenchymal stem cells （MSC） from bone marrow to differentiate into hepatocytic cells in vitro. Furthermore, we assessed the influence of cocultured liver cells on induction of liver-specific gene expression. METHODS： Mesenchymal stem cells were marked with green fluorescent protein （GFP） by retroviral gene transduction. Clonal marked MSC were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with SCF, HGF, EGF, and FGF-4 alone, or in presence of freshly isolated rat liver cells. Cells in cocultures were harvested and GFP＋ or GFP- cells were separated using fluorescence activated cell sorting. RT-PCR analysis for the stem cell marker Thyl and the hepatocytic markers CK-18, albumin, CK-19, and AFP was performed in the different cell populations. RESULTS： Under the specified culture conditions, rat MSC cocultured with liver cells expressed albumin-, CK-18, CK-19, and AFP-RNA over 3 weeks, whereas MSC cultured alone did not show liver specific gene expression, CONCLUSION： The results indicate that （1） rat MSC from bone marrow can differentiate towards hepatocytic lineage in vitro, and （2） that the microenvironment plays a decisive role for the induction of hepatic differentiation of rMSC.

关键词： Mesenchymal stem cells Liver-specific differentiation Coculture

How to perform gastrointestinal ultrasound: anatomy and normal findings

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World Journal of Gastroenterology 2017年第38期23卷 6931-6941页

作者： Nathan S S Atkinson Robert V Bryant Yi Dong Christian Maaser Torsten Kucharzik Giovanni Maconi Anil K Asthana michael Blaivas Adrian Goudie Odd Helge Gilja Dieter Nuernberg Dagmar Schreiber-dietrich Christoph F dietrich Translational Gastroenterology Unit Oxford University Hospitals NHS Foundation Trust School of Medicine University of Adelaide Department of Gastroenterology and Hepatology Royal Adelaide Hospital Department of Ultrasound Zhongshan Hospital Fudan University Ambulanzzentrum Gastroenterologie Klinikum Lüneburg Department of Gastroenterology Stadtisches Klinikum Luneburg gGmbH Gastrointestinal Unit Department of Biomedical and Clinical Sciences 'L.Sacco' University Hospital Department of Gastroenterology and Hepato-logy The Alfred Hospital Monash University Piedmont Hospital Department of Emergency Medicine Fremantle Hospital and Health Service Emergency Department National Centre for Ultrasound in Gastro- enterology Haukeland University Hospital Department of Clinical Medicine University of Bergen Department of Gastroenterology Brandenburg Medical School Med. Klinik 2 Caritas-Krankenhaus Bad Mergentheim

Gastrointestinal ultrasound is a practical, safe, cheap and reproducible diagnostic tool in inflammatorybowel disease gaining global prominence amongst clinicians. Understanding the embryological processes of the intestinal tract assists in the interpretation of abnormal sonographic findings. In general terms, the examination principally comprises interrogation of the colon, mesentery and small intestine using both lowfrequency and high-frequency probes. Interpretation of findings on GIUS includes assessment of bowel wall thickness, symmetry of this thickness, evidence of transmural changes, assessment of vascularity using Doppler imaging and assessment of other specific features including lymph nodes, mesentery and luminal motility. In addition to B-mode imaging, transperineal ultrasonography, elastography and contrast-enhanced ultrasonography are useful adjuncts. This supplement expands upon these features in more depth.

关键词： Ultrasound Intestinal Inflammatory bowel disease Guidelines Teaching

大型X射线光学仪器:单层镜和多层镜的制造与表征(英文)

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光学精密工程 2007年第12期15卷 1869-1877页

作者： michael Strmer dietrich Huβler Wolfgang Jger Rüdiger Bormann Institute of Materials Research GKSS-Research Centre Geesthacht GmbHMax-Planck-Strasse 121502 GeesthachtGermany Microanalysis of Materials Faculty of EngineeringUniversity KielKaiserstrasse 224143 KielGermany

150 ～500 mm长度的各种X射线光学元件可用于光束导引,光束调整,以及单色化。本文介绍了两种不同的大型X射线反射镜。第一种为单层反射镜,这种反射镜以2°掠入射角在软X射线区(50 ～200 eV)起全反射镜作用,可用于自由电子激光器,如德国... 详细信息

150 ～500 mm长度的各种X射线光学元件可用于光束导引,光束调整,以及单色化。本文介绍了两种不同的大型X射线反射镜。第一种为单层反射镜,这种反射镜以2°掠入射角在软X射线区(50 ～200 eV)起全反射镜作用,可用于自由电子激光器,如德国汉堡的FLASH。第二种是多层镜,由于它的布喇格反射特性,适于作为反射镜以0 .4 ～1°的入射角用于硬X射线区(20 ～50 keV) ,如层析光束线的同步辐射存储环中。两种反射镜都用最新物理汽相淀积法制备,并用磁控溅射来实现X射线光学应用所需要的优良光学品质。这一淀积工艺使不同批次的镀膜稳定性良好,有利于实际反射镜在优质衬底上的最后淀积。单层镜和多层镜在它们的相关能量范围内都有很高的反射率,表面粗糙度也很低,且在整个光学波长区这些特性表现均匀。文中所叙相关研究都是借助X射线反射计量(XRR)法,透射电子显微镜(TEM)、光学轮廓仪(OP) ,以及原子力显微镜(AFM)完成的。

关键词： X射线光学多层膜反射镜全反射镜 X射线反射测量磁控溅射同步辐射自由电子激光器

Serous pancreatic neoplasia, data and review

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World Journal of Gastroenterology 2017年第30期23卷 5567-5578页

作者： Christoph F dietrich Yi Dong Christian Jenssen Valentina Ciaravino michael Hocke Wen-Ping Wang Eike Burmester Kathleen Moeller Nathan SS Atkinson Paola Capelli Mirko D’Onofrio Medizinische Klinik 2 Caritas-Krankenhaus Bad Mergentheim Ultrasound Department First Affiliated Hospital of Zhengzhou University Department of Ultrasound Zhongshan HospitalFudan University Department of Internal Medicine Krankenhaus Markisch Oderland Strausberg/Wriezen Department of Radiology G.B Rossi University HospitalUniversity of Verona Department of Internal Medicine 2 Helios Hospital Meiningen GmbH Department of Internal Medicine I Sana Klinikum Lichtenberg Translational Gastroenterology Unit Oxford University Hospitals NHS Foundation Trust Department of Pathology G.B Rossi University HospitalUniversity of Verona Department of Radiology GB Rossi University HospitalUniversity of Verona

AIM To describe the imaging features of serous neoplasms of the pancreas using ultrasound, endoscopic ultrasound, computed tomography and magnetic resonance *** This multicenter international collaboration enhances a literature review to date, reporting features of 287 histologically confirmed cases of serous pancreatic cystic neoplasms(SPN). RESULTS Female predominance is seen with most SPN presenting asymptomatically in the 5th through 7th decade. Mean lesion size was 38.7 mm, 98% were single, 44.2% cystic, 46% mixed cystic and solid, and 94% hypoechoic on B-mode ultrasound. Vascular patterns and contrast-enhancement profiles are described as hypervascular and *** The described ultrasound features can aid differentiation of SPN from other neoplastic lesions under most circumstances.

关键词： Guideline Cancer Ultrasound Endoscopic ultrasound Elastography