检索结果-南通市图书馆

National Science Review 2021年第8期8卷 134-135页

作者： helmut C?lfen Department of Chemistry University of Konstanz

Materials are the cornerstone of human society. Environmentally friendly and sustainable bio-based materials are the key to achieving sustainable development, which is urgently needed to meet global challenges [1–4]. Different from petroleum-based materials, bio-based plant materials are derived from carbon dioxide in the atmosphere, which is fixed by the photosynthesis of plants to form biomaterials like wood. The use of these materials by humans can be traced back to ancient times. However,

关键词：

Chirality communications between inorganic and organic compounds

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

SmartMat 2021年第1期2卷 17-32页

作者： Bing Ni helmut Cölfen Physical Chemistry Department of ChemistryUniversity of KonstanzKonstanzGermany

1|INTRODUCTION Chirality spans over almost every size range,from mole-cules to biological systems and even to *** is one of the fascinating geometrical properties with a lot of amazing manifestations in the material *** chemi-cal researchers,we are more interested in chirality at the molecular scale and *** molecules are found important in life science,agrochemicals,pharma-ceutical industries,biosensing,display materials,and so forth.1–5 Chirality stems from a structure lacking sym-metry elements of inversion symmetry and mirror‐plane,which makes the structure not superimposable with its mirror *** these two kinds of symmetries,any structure is chiral,besides conventional chiral organics or spiral inorganic *** essence of chirality is the stereochemistry of molecules or nanostructures.

关键词： Chiral inorganic mirror

Cancer risk in IBD: How to diagnose and how to manage DALM and ALM

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2011年第27期17卷 3184-3191页

作者： helmut Neumann Michael Vieth Cord Langner Markus F Neurath Jonas Mudter Department of Medicine 1 Department of SurgeryUniversity of Erlangen-Nuremberg Ulmenweg 1891054 ErlangenGermany Institute of Pathology Klinikum Bayreuth GmbHPreuschwitzer Str. 10195445 BayreuthGermany Institute of Pathology Medical University of GrazAuenbruggerplatz 25A-8036 Graz Austria

The risk of developing neoplasia leading to colorectal cancer is significantly increased in ulcerative colitis (UC) and most likely in Crohn's disease. Several endoscopic surveillance strategies have been implemented to identify these lesions. The main issue is that colitisassociated neoplasms often occurs in flat mucosa, often being detected on taking random biopsies rather than by identification of these lesions via endoscopic imaging. The standard diagnostic procedure in long lasting UC is to take four biopsies every 10 cm. Image enhancement methods, such as chromoendoscopy and virtual histology using endomicroscopy, have greatly im- proved neoplasia detection rates and may contribute toreduced random biopsies by taking targeted "smart" biopsies. Chromoendoscopy may effectively be performed by experienced endoscopists for routine screening of UC patients. By contrast, endomicroscopy is often only available in selected specialized endoscopic centers. Importantly, advanced endoscopic imaging has the poten- tial to increase the detection rate of neoplasia whereas the interplay between endoscopic experience and interpretation of histological biopsy evaluation allows the physician to make a proper diagnosis and to find the appropriate therapeutic approach. Colitis-associated intraepithelial neoplasms may occur in flat mucosa of endoscopically normal appearance or may arise as dysplasia-associated lesion or mass (DALM), which may be indistinguishable from sporadic adenomas in healthy or non-colitis mucosa [adenoma-like mass (ALM)]. The aim of this review was to summarize endoscopic and histological characteristics of DALM and ALM in the context of therapeutic procedures.

关键词：诊断程序 ALM 风险 IBD 溃疡性结肠炎管理癌症治疗程序

Influence of vascular endothelial growth factor and radiation on gap junctional intercellular communication in glioblastoma multiforme cell lines

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2017年第11期12卷 1816-1822页

作者： Reinhardt Krcek Pauline Latzer Irenaus Anton Adamietz helmut Biihler Carsten Theiss Institute of Anatomy Department of CytologyRuhr-University BochumBochumNorth Rhine-WestphaliaGermany Department of Radiotherapy and Radio-Oncology University Medical Centre MarienhospitalRuhr-University BochumHerneNorth Rhine-WestphaliaGermany Institute for Molecular Oncology Radio-Biology and Experimental RadiotherapyUniversity Medical Centre MarienhospitalRuhr-University BochumHerneNorth Rhine-WestphaliaGermany

Glioblastoma multiforme （GBM） is a highly aggressive glial brain tumor with an unfavorable prognosis despite all current therapies including surgery, radiation and chemotherapy. One characteristic of this tumor is a strong synthesis of vascular endothelial growth factor （VEGF）, an angiogenesis factor, followed by pronounced vascularization. VEGF became a target in the treatment of GBM, for example with bevacizumab or the tyrosine kinase inhibitor axitinib, which blocks VEGF receptors. To improve patients＇ prognosis, new targets in the treatment of GBM are under investigations. The role of gap junctions in GBM remains un- known, but some experimental therapies affect these intercellular channels to treat the tumor. Gap junctions are composed of connexins to allow the transport of small molecules between adjacent cells through gap junc- tional intercellular communication （GJIC）. Based on data derived from astrocytes in former studies, which show that VEGF is able to enhance GJIC, the current study analyzed the effects of VEGF, radiation therapy and VEGF receptor blockade by axitinib on GJIC in human GBM cell lines U-87 and U-251. While VEGF is able to induce GJIC in U-251 cells but not in U-87 cells, radiation enhances GJIC in both cell lines. VEGF reocptor blockade by axitinib diminishes radiation induced effects in U-251 partially, while increases GJIC in U-87 cells. Our data indicate that VEGF and radiation are both modifying components of GJ1C in pathologic brain tumor tissue.

关键词： cell communication vascular endothelial growth factor irradiation vascular endothelial growth factor-receptor blockade glioma neurobiotin connexin cell culture immunohistochemistry microinjection

维普期刊数据库

Experimental investigation on local shear stress and turbulence intensities over a rough non-uniform bed with and without sediment using 2D particle image velocimetry

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2020年第2期35卷 193-202页

作者： Petr Lichtneger Christine Sindelar Johannes Schobesberger Christoph Hauer helmut Habersack CD-Laboratory of Sediment Research and Management Institute of Water ManagementHydrology and Hydraulic EngineeringDepartment Water-Atmosphere-EnvironmentUniversity of Natural Resources and Life Sciences

The current work focuses on locally resolving velocities,turbulence,and shear stresses over a rough bed with locally non-uniform character.A nonporous subsurface layer and fixed interfacial sublayer of gravel and sand were water-worked to a nature-like bed form and additionally sealed in a hydraulic ***-dimensional Particle Image Velocimetry(2 D-PIV) was applied in the vertical plane of the experimental flume *** with clear water and weak sediment transport were done under slightly supercritical flow to ensure sediment transport conditions without formation of considerable sediment deposits or *** study design included analyzing the double-averaged flow parameters of the entire measurement domain and investigating the flow development at 14 consecutive vertical *** geometrical variabilities as well the presence of sediment were mainly reflected in the vertical velocity *** the vertical velocity decreased over the entire depth in presence of sediment transport,the streamwise velocity profile was reduced only within the interfacial *** the region with decelerating flow conditions,however,the streamwise velocity profile systematically increased along the entire depth *** increase in the main velocity(reduction of flow resistance)correlated with a decrease of the turbulent shear and main normal ***,effects of rough bed smoothening and drag force reduction were experimentally documented within the interfacial sublayer due to mobile ***,the current study leads to the conclusion that in nonuniform flows the maximum Reynolds stress values are a better predictor for the bed shear stress than the linearly extrapolated Reynolds stress *** is an important finding because,in natural flows,uniform conditions are rare.

关键词： Turbulence measurement Local bed shear stress Sediment transport and flow interaction Hydraulic flume experiment Particle image velocimetry

Revision of the Conchostracan Genus Tenuestheria from the Upper Cretaceous Lanxi Formation in Zhejiang and Its Biostratigraphic Significance in Southeast China

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2007年第6期81卷 925-930页

作者： LI Gang WAN Xiaoqiao helmut WILLEMS David J. BATTEN State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China China University ofGeosciences Beijing 100083 China Department of Geosciences University of Bremen Klagenfurter Strαβe 2 28359 Bremen Germany School of Earth Atmospheric and Environmental Sciences University of Manchester Oxford Road Manchester M13 9PL and Institute of Geography and Earth Sciences University of Wales Aberystwyth SY23 3DB UK

The diagnosis of the conchostracan genus Tenuestheria from the Lanxi Formation in Jinhua, Zhejiang Province in Southeast China is revised following an examination of the type species under a scanning electron microscope, which revealed some morphological features on the carapace that had not been recognized previously. The importance of the Tenuestheria Fauna is considered in the context of correlation of six Turonian-Santonian formations in this region of China. The value of the Cenomanian Nemestheria and Turonian Linhaiella faunas in correlating the underlying early Late Cretaceous formations is also noted.

关键词： conchostraca Tenuestheria Upper Cretaceous Southeast China

维普期刊数据库

18F-FDG-PET for Assessing Biological Viability and Prognosis in Liver Transplant Patients with Hepatocellular Carcinoma

在线全文

学校读者我要写书评

暂无评论

Journal of Clinical and Translational Hepatology 2017年第3期5卷 224-234页

作者： Arno Kornberg Martina Schernhammer helmut Friess Department of Surgery Klinikum rechts der Isar Technical University Munich Germany

Liver transplantation (LT) has become standard of care in patients with non-resectable early stage hepatocellular carcinoma (HCC) in liver ***,patient selection for LT is strictly based on tumor size and number,provided by the Milan *** may,however,exclude patients with advanced tumor load but favourable biology from a possibly curative treatment *** became clear in recent years that biological tumor viability rather than tumor macromorphology determines posttransplant *** particular,microvascular invasion and poor grading reflect tumor aggressiveness and promote the risk of tumor *** biopsy is not applicable due to tumor heterogeneity and risk of tumor cell seeding.18F-fludeoxyglucose (18F-FDG) positron emission tomography (PET),an established nuclear imaging device in oncology,was demonstrated to non-invasively correlate with unfavorable histopathologic ***,there is an increasing amount of evidence that 18F-FDG-PET is very useful for identifying eligible liver transplant patients with HCC beyond standard criteria but less aggressive tumor *** order to safely expand the HCC selection criteria and the pool of eligible liver recipients,tumor evaluation with 18F-FDG-PETshould be implemented in pretransplant decision process.

关键词： Hepatocellular carcinoma Liver transplantation 18F-fludeoxyglucose positron emission tomography Tumor biology Tumor recurrence

Climate change and infectious diseases of wildlife： Altered interactions between pathogens, vectors and hosts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2013年第3期59卷 427-437页

作者： Milena GALLANA Marie-Pierre RYSER-DEGIORGIS Thomas WAHLI helmut SEGNER Department of Infectious Diseases and Pathobiology Vetsuisse Faculty University of Bern CH-3012 Bern Switzerland

Infectious diseases result from the interactions of host, pathogens, and, in the case of vector-borne diseases, also vectors. The interactions involve physiological and ecological mechanisms and they have evolved under a given set of environmental conditions. Environmental change, therefore, will alter host-pathogen-vector interactions and, consequently, the distribution, intensity, and dynamics of infectious diseases. Here, we review how climate change may impact infectious diseases of aquatic and terrestrial wildlife. Climate change can have direct impacts on distribution, life cycle, and physiological status of hosts, pathogens and vectors. While a change in either host, pathogen or vector does not necessarily translate into an alteration of the disease, it is the impact of climate change on the interactions between the disease components which is particularly critical for altered disease risks. Finally, climate factors can modulate disease through modifying the ecological networks host-pathogen-vector systems are belonging to, and climate change can combine with other environmental stressors to induce cumulative effects on infectious diseases. Overall, the influence of climate change on infectious diseases involves different mechanisms, it can be modulated by phenotypic acclimation and/or genotypic adaptation, it depends on the ecological context of the host-pathogen-vector interactions, and it can be modulated by impacts of other stressors. As a consequence of this complexity, non-linear responses of disease systems under climate change are to be expected. To improve predictions on climate change impacts on infectious disease, we suggest that more emphasis should be given to the integration of biomedical and ecological research for studying both the physiological and ecological mechanisms which mediate climate change impacts on disease, and to the development of harmonized methods and approaches to obtain more comparable results, as this would support the discr

关键词：陆生野生动物气候变化相互作用载体系统病原体传染病宿主感染性疾病

Effect of household water treatment with chlorine on diarrhea among children under the age of five years in rural areas of Dire Dawa,eastern Ethiopia:a cluster randomized controlled trial

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2020年第3期9卷 138-139页

作者： Ephrem Tefera Solomon Sirak Robele helmut Kloos Bezatu Mengistie Ethiopian Institute of Water Resources Addis Ababa UniversityAddis AbabaEthiopia Haramaya University College of Health and Medical SciencesHararEthiopia 不详

Background:Diarrheal disease is a leading cause of child mortality and morbidity *** water treatment with chlorine significantly reduces morbidity due to waterborne ***,the effect of point-ofuse(POU)water treatment in improving the quality of water in areas where POU is not provided free of charge and the effectiveness of home visits in inspiring household members to use POU regularly have not been *** objective of this study was to evaluate the effectiveness of drinking water disinfection by chlorination on diarrheal disease reduction among children under the age of 5 years in rural eastern ***:A cluster randomized controlled trial was carried out in rural Dire Dawa from October 2018 through January *** 405 households were randomized to intervention and control arms and intervention materials were distributed after conducting a baseline *** trial evaluated the effectiveness of household drinking water disinfection by chlorination in reducing incidence of diarrhea among children under the age of 5 *** households received 1.2%sodium hypochlorite with demonstration of its proper *** in the control households continued with their usual habits of water collection and water *** estimation equations(GEE)with log link Poisson distribution family and exchangeable correlation matrix was used to compute crude incidence rate ratio(IRR),adjusted IRR and the corresponding 95%confidence ***:In the intervention households,in total,281 cases of diarrhea were documented(8.7 cases per 100 personweeks observation);in the control households,in total 446 cases of diarrhea were documented(13.8 cases per 100 person-weeks observation).A 36.0%(adjusted IRR=0.64,95%CI:0.57–0.73)reduction in incidence of diarrhea was observed in the intervention arm when compared with the control *** highest and the lowest reductions were obtained in children of age ranges 1 to 2 years

关键词： Diarrhea Effect Water treatment with chlorine Under-five children WaterGuard Cluster randomized controlled trial Ethiopia

Case Report: Bilateral Pneumothoraces due to Targeted Tumor Therapy with Regorafenib in a Young Woman with Metastatic Colorectal Cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Case Reports in Clinical Medicine 2022年第5期11卷 139-145页

作者： Tobias Rachow Tim Sandhaus Thomas Ernst helmut Schiffl Susanne M. Lang Klinik für Innere Medizin II Universit&auml tsklinikum Jena Jena Germany Klinik für Innere Medizin V Universit&auml tsklinikum Jena Jena Germany Klinik für Herz- und Thoraxchirurgie Universit&auml tsklinikum Jena Jena Germany Medizinische Klinik IV LMU München München Germany

Background: Colorectal cancer is one of the most common cancer types, frequently metastasizing into the lungs. Treatment options have been vastly improved over the last years. With the increasing use of targeted therapies, novel and rare adverse effects can be seen. Case Presentation: A 43-year-old woman presented in our oncology department with chest pain and dyspnea. The patient was diagnosed with colorectal cancer seven years earlier and had received chemoradiation, surgery, and multiple chemotherapies before she was started on regorafenib because of progressive pulmonary metastases. Computed tomography scans demonstrated cavitation of former nodular bilateral pulmonary metastases. After drainage and resolution of the right-sided pneumothorax, the patient returned eleven days later with recurrent symptoms caused by left-sided tension pneumothorax. Video-assisted thoracoscopy and bilateral pleurodeses were performed. Persistent air leaks with severe pain and pulmonary infiltrates led to the death of the patient. Conclusions: This case demonstrates the efficacy of oral antiangiogenetic therapy in advanced metastatic colorectal cancer. Nevertheless, it also depicts an important potential side effect by transforming multiple solid lung metastases into cavitations which led to recurrent pneumothoraces. Special attention should be paid to this phenomenon as treatment of these complications can be challenging.

关键词： Regorafenib Pneumothorax Pulmonary Metastases Colorectal Cancer