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| 1 | 等渗性碘克沙醇与非离子型低渗性对比剂的肾毒性比较:随机对照试验的Meta分析显示文摘目的 比较随机临床试验中等渗性碘克沙醇与非离子型低渗性对比剂(LOCM)的肾毒性。方法 本Meta分析系统地检索了MEDLINE、EMBASE、BIOSIS、Web of Science、ISI知网、Medizin近期期刊报道、Cochrane图书馆(截至2007年8月)、有关试验记录、会议记录及文献列表中的研究,也向所有的对比剂制造商咨询了未能检索到的研究。 | M.C.Heinrich L.Hberle V.Müller W.Bautz M.Uder 蒋涛 | 2009 | 国际医学放射学杂志2009，32，2： | 52 |
| 2 | AGNP精神科治疗药物监测共识指南:2011显示文摘治疗药物监测(Therapeutic drug monitoring,TDM),如通过定量测定血清或血浆药物浓度指导用药剂量优化,已经成为对患者进行精神药物治疗的很有价值的工具。在患者用药依从性难以判断、药物耐受性不佳、治疗剂量下无效以及可能存在药代动力学药物-药物相互作用等情况下,测定药物浓度是很有用的。在精神科,有可能明显获益于TDM的主要患者群体包括儿童、孕妇、老年患者、智力障碍患者、涉及司法的患者、已知或怀疑携带药代动力学相关基因变异的患者,以及合并躯体疾病影响药代动力学的患者。然而,只有将TDM充分整合到临床治疗过程中去,才能发挥其优化药物治疗的潜在优势。为了促进TDM的合理应用,神经精神药理学与药物精神病学协会(Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie,AGNP)的TDM专家组在2004年发表了精神药物治疗药物监测指南。之后,随着知识不断更新,又有许多可能需要进行TDM的新药上市。因此,本次更新将神经精神药物的种类扩展到了128种,并将其TDM必要性划分为从'强烈推荐'到'可能有用'的四个等级。经过大量细致且全面的文献检索与分门别类的汇总整理,将基于循证医学理念的'治疗参考浓度范围'和'剂量相关参考浓度范围'呈现给大家。本共识指南引入了'实验室警戒浓度'的新概念,即实验室需要马上告知治疗医生的药物浓度上限。本共识指南还给出了诸如药物作为细胞色素P450酶的底物和抑制剂的性质,代谢物与母药浓度比值的常见范围,以及与结果解释相关的内容,还提供了何时将TDM与遗传药理学检测相结合的建议。遵循本指南,有助于改善许多患者精神药物治疗的效果,特别是那些存在药代动力学异常的患者。TDM是一门交叉学科,有时针对看起来不一致的数据,需要多学科坦诚地讨论,只有这样,患者才能从这种合作中获益。 | Hiemke C Baumann P Bergemann N Conca A Dietmaier O Egberts K Fric M Gerlach M Greiner C Gründer G Haen E Havemann-Reinecke U Jaquenoud Sirot E Kirchherr H Laux G Lutz UC Messer T Müller MJ Pfuhlmann B Rambeck B Riederer P Schoppek B Stingl J Uhr M Ulrich S Waschgler R Zernig G 李文标(译) 果伟(译) 阮灿军(译) 贺静(译) 汤宜朗(审校) 王传跃(审校) | 2016 | 实用药物与临床2016，19，10： | 37 |
| 3 | 新千年初的欧洲粉末冶金显示文摘本文回顾了欧洲粉末冶金协会 (EPMA)成立十年来的工作。这几年来EPMA组织并完成了两个主题网络 ,即粉末冶金过程模拟和金属注塑成型网络 ,建立了该协会的网站 ;评述了粉末冶金市场的发展 ,自 1 993年至 1 999年欧洲粉末冶金市场增长了 5 0 % ;强调了粉末冶金在汽车业应用的重要性 ;报道了欧洲粉末冶金发展动向 ,如温压汽车连杆已研制成功 。 | Lothar Albano-Müller 王崇琳 | 2001 | 粉末冶金工业2001，11，2： | 24 |
| 4 | 西藏甲玛铜多金属矿区成矿斑岩的岩浆混合作用:石英及长石斑晶新证据显示文摘西藏甲玛矿区斑岩内石英和长石斑晶的阴极发光(CL)特征及元素含量变化有效记录了岩浆演化、混合及补给事件。石英斑晶的显微生长结构表明,原始岩浆经历过2次铁镁质岩浆混合作用。根据石英斑晶中Ti含量的变化可知,在2次溶蚀前后,石英结晶温度分别增高了约110℃和80℃。此外,斜长石斑晶的反环带及其Ba、Sr、Fe等元素的浓度梯度、钾长石的镶边结构、黑云母的筛状结构等,都有效地证明了铁镁质岩浆与长英质岩浆混合作用的存在。根据这些研究结果,初步构建了该矿区岩浆混合作用模型,并推测了岩浆混合过程。在16Ma左右,岩石圈地幔拆沉,软流圈物质上涌导致正常下地壳部分熔融,产生了含Mo的钾质岩浆。原始岩浆房内形成了第Ⅰ世代自形的高温石英晶体核。软流圈上涌诱发了含大量地幔组分的新生镁铁质下地壳部分熔融,产生了含Cu、富水、高f(O2)的埃达克质岩浆熔体,并与含Mo的长英质岩浆发生了第1次岩浆混合作用。在此过程中,早期石英核部溶蚀,形成了高Ti的溶蚀表面。这些高f(O2)的混合岩浆在浅部地壳形成了大型岩浆房,并排泄出含Cu、Mo岩浆流体。在岩浆房中,石英晶体形成了均匀的生长环带和第Ⅱ世代的石英斑晶核。地幔减薄和岩石圈拆沉直接引起了地壳强烈伸展,形成了垂直于碰撞带的正断层系统和裂谷,使岩浆房内部的压力急剧减小,岩浆快速侵位。岩浆房的突然腾空,诱发了地幔物质上涌,造成了第2次基性岩浆的混入,促使第Ⅰ世代和第Ⅱ世代石英斑晶的边缘发生溶蚀。正是两次基性岩浆的加入,为成矿提供了大量的Cu、S。这是形成甲玛超大型铜多金属矿床不可或缺的因素。 | 彭惠娟 汪雄武 Müller Axel 秦志鹏 侯林 周云 | 2011 | 矿床地质2011，30，2： | 18 |
| 5 | Cardiopulmonary,complications in chronic liver disease显示文摘有肝硬化和门静脉高血压的病人展出典型心血管、肺的血液动力学的变化。一个 vasodilatatory 状态和影响心脏、肺的功能的亢奋的动态发行量统治发行量。最近定义的肝脏硬化症的心肌症可以影响收缩、心脏舒张的功能,并且暗示机电的畸形。另外,循环 homoeostasis 的压力感受器功能和规定被损害。肺的机能障碍涉及在一些病人与肝肺症候群和 portopulmonary 高血压的发展传播畸形。最近的研究集中于血液动力学、神经元介质的 dysregulation 具有为在肝硬化的心血管、肺的复杂并发症的发展的主要重要性的断言。这个方面是重要的在这些病人的管理考虑。 | SφrenMφller JensHHenriksen | 2006 | World Journal of Gastroenterology2006，12，4： | 17 |
| 6 | 农田和森林土壤中氧化亚氮的产生与还原(英文)显示文摘采用土壤淤浆方法对丹麦农田和山毛榉森林土壤反硝化过程中N2 O的产生与还原进行了研究 ,同时考察了硝酸根和铵离子对反硝化作用的影响 .结果表明 ,森林土壤反硝化活性大于农田土壤 ,但农田土壤中N2 O还原活性大于森林土壤 ,表现在农田和森林土壤中N2 O/N2 的产生比率分别为 0 .11和 3 .65 .硝酸根和铵离子能促进两种土壤中的N2 O产生 ,但可降低农田土壤中的N2 O还原速率 .与农田土壤相比 ,硝酸根可降低森林土壤N2 O的还原能力 ,而铵离子却表现出对N2 O还原的促进作用 .培养 1周内尽管农田土壤中硝酸根始终存在 ,但几乎所有产生的N2 O都被还原成N2 .然而 ,只有当硝酸根几乎耗尽 ,森林土壤中N2 O的还原才开始进行 .由于两种土壤 pH值的不同造成硝酸根对N2 O还原抑制作用的差异 ,因为酸性条件下硝酸根对N2O还原的抑制较强 .因此 ,土壤消耗大气N2 O的适宜条件为厌氧 ,pH中性和硝酸根含量低 . | 于克伟 陈冠雄 StenStruwe AnneliseKjФller | 2000 | 应用生态学报2000，11，3： | 16 |
| 7 | 胰腺的癌症诊断由免费并且 exosomal miRNA显示文摘 Patients with pancreatic adenocarcinoma(PaCa) have a dismal prognosis. This is in part due to late diagnosis prohibiting surgical intervention, which provides the only curative option as PaCa are mostly chemo- and radiation resistance. Hope is raised on a reliable noninvasive/minimally invasive diagnosis that is still missing. Recently two diagnostic options are discussed, serum MicroRNA(miRNA) and serum exosomes. Serum miRNA can be free or vesicle-, particularly, exosomesenclosed. This review will provide an overview on the current state of the diagnostic trials on free serum miRNA and proceed with an introduction of exosomes that use as a diagnostic tool in serum and other body fluids has not received sufficient attention, although serum exosome miRNA in combination with protein marker expression likely will increase the diagnostic and prognostic power. By their crosstalk with host cells, which includes binding-initiated signal transduction, as well as reprogramming target cells via the transfer of proteins, mRNA and miRNA exosomes are suggested to become a most powerful therapeutics. I will discuss which hurdles have still to be taken as well as the different modalities, which can be envisaged to make therapeutic use of exosomes. PaCa are known to most intensely crosstalk with the host as apparent by desmoplasia and frequent paraneoplastic syndromes. Thus, there is hope that the therapeutic application of exosomes brings about a major breakthrough. | Margot Zller | 2013 | World Journal of Gastrointestinal Pathophysiology2013，4，4： | 15 |
| 8 | 非线性机械系统PID控制渐近稳定性分析显示文摘应用Lyapunov直接稳定性理论和LaSalle不变性原理,证明了不确定非线性机械系统常用线性PID控制的半全局渐近稳定性.同时证明了为提高系统的响应速度而发展的一种非线性PI加D(NPI—D)控制系统的全局渐近稳定性.两自由度机器人系统的数值仿真结果验证了NPI—D控制的良好性能. | 苏玉鑫 郑春红 Peter C.Müller | 2008 | 自动化学报2008，34，12： | 15 |
| 9 | Extrahepatic complications to cirrhosis and portal hypertension: Haemodynamic and homeostatic aspects显示文摘In addition to complications relating to the liver, patients with cirrhosis and portal hypertension develop extrahepatic functional disturbances of multiple organ systems. This can be considered a multiple organ failure that involves the heart, lungs, kidneys, the immune systems, and other organ systems. Progressive fibrosis of the liver and subsequent metabolic impairment leads to a systemic and splanchnic arteriolar vasodilatation. This affects both the haemodynamic and functional homeostasis of many organs and largely determines the course of the disease. With the progression of the disease, the circulation becomes hyperdynamic with cardiac, pulmonary as well as renal consequences for dysfunction and reduced survival. Infections and a changed cardiac function known as cirrhotic cardiomyopathy may be involved in further aggravation of other complications such as renal failure precipitatingthe hepatorenal syndrome.Patients with end-stage liver disease and related complications as for example the hepatopulmonary syndrome can only radically be treated by liver transplantation.As a bridge to this treatment,knowledge on the mechanisms of the pathophysiology of complications is essential for the choice of vasoactive drugs,antibiotics,drugs with specific effects on fibrogenesis and inflammation,and drugs that target specific receptors. | S?ren M?ller Jens H Henriksen Flemming Bendtsen | 2014 | World Journal of Gastroenterology2014，20，42： | 14 |
| 10 | Spinal cord involvement in patients with cirrhosis显示文摘A severe spinal cord involvement may rarely occur in patients with cirrhosis and other chronic liver diseases;this complication is usually associated with overt liver failure and surgical or spontaneous porto-systemic shunt.Hepatic myelopathy(HM)is characterized by progressive weakness and spasticity of the lower extremities,while sensory and sphincter disturbances have rarely been described and are usually less important.The diagnosis is assigned in the appropriate clinical setting on clinical grounds after the exclusion of other clinical entities leading to spastic paraparesis.Magnetic resonance imaging is often unremarkable;however,also intracerebral corticospinal tract abnor-malities have been reported recently.The study of motor evoked potentials may disclose central conduction abnormalities even before HM is clinically manifest.HM responds poorly to blood ammonia-lowering and other conservative medical therapy.Liver transplantation represents a potentially definitive treatment for HM in patients with decompensated cirrhosis of Child-Pugh B and C grades.Other surgical treatment options in HM include surgical ligation,shunt reduction,or occlusion by interventional procedures. | Raffaele Nardone Yvonne Hller Monica Storti Piergiorgio Lochner Frediano Tezzon Stefan Golaszewski Francesco Brigo Eugen Trinka | 2014 | World Journal of Gastroenterology2014，20，10： | 12 |
| 11 | 欧洲心脏杂志研究称:空气污染导致每年全球880万人死亡,因心血管病死亡是呼吸疾病的两倍显示文摘根据发表在《欧洲心脏杂志》上的一项研究,2015年,空气污染(PM2.5和臭氧)在整个欧洲造成了79万人死亡,在这些死亡中,40%.80%死于心血管疾病。空气污染导致的心血管疾病死亡人数是呼吸系统疾病死亡人数的两倍。研究人员还发现,全球大气污染造成的死亡人数估计为880万,而不是先前估计的450万。这意味着空气污染每年造成的额外死亡比吸烟多,世界卫生组织估计吸烟导致额外720万人死亡。 | Lelieveld J Klingmüller K Pozzer A | 2019 | 疾病监测2019，34，3： | 12 |
| 12 | Pathophysiology of chronic pancreatitis显示文摘Chronic pancreatitis(CP)is an inflammatory disease of the pancreas characterized by progressive fibrotic destruction of the pancreatic secretory parenchyma.Despite the heterogeneity in pathogenesis and involved risk factors,processes such as necrosis/apoptosis,inflammation or duct obstruction are involved.This fibrosing process ultimately leads to progressive loss of the lobular morphology and structure of the pancreas,deformation of the large ducts and severe changes in the arrangement and composition of the islets.These conditions lead to irreversible morphological and structural changes resulting in impairment of both exocrine and endocrine functions.The prevalence of the disease is largely dependent on culture and geography.The etiological risk-factors associated with CP are multiple and involve both genetic and environmental factors.Throughout this review the M-ANNHEIM classification system will be used,comprising a detailed description of risk factors such as:alcohol-consumption,nicotineconsumption,nutritional factors,hereditary factors,efferent duct factors,immunological factors and miscellaneous and rare metabolic factors.Increased knowledge of the different etiological factors may encourage the use of further advanced diagnostic tools,which potentially will help clinicians to diagnose CP at an earlier stage.However,in view of the multi factorial disease and the complex clinical picture,it is not surprising that treatment of patients with CP is challenging and often unsuccessful. | Christina Brock Lecia Mφller Nielsen Dina Lelic Asbjφrn Mohr Drewes | 2013 | World Journal of Gastroenterology2013，19，42： | 11 |
| 13 | Deep-learning based denoising and reconstruction of super-resolution structured illumination microscopy images显示文摘Super-resolution structured illumination microscopy(SR-SIM) provides an up to twofold enhanced spatial resolution of fluorescently labeled samples. The reconstruction of high-quality SR-SIM images critically depends on patterned illumination with high modulation contrast. Noisy raw image data(e.g., as a result of low excitation power or low exposure time), result in reconstruction artifacts. Here, we demonstrate deep-learning based SR-SIM image denoising that results in high-quality reconstructed images. A residual encoding–decoding convolutional neural network(RED-Net) was used to successfully denoise computationally reconstructed noisy SR-SIM images.We also demonstrate the end-to-end deep-learning based denoising and reconstruction of raw SIM images into high-resolution SR-SIM images. Both image reconstruction methods prove to be very robust against image reconstruction artifacts and generalize very well across various noise levels. The combination of computational image reconstruction and subsequent denoising via RED-Net shows very robust performance during inference after training even if the microscope settings change. | ZAFRAN HUSSAIN SHAH MARCEL MÜLLER TUNG-CHENG WANG PHILIP MAURICE SCHEIDIG AXEL SCHNEIDER MARK SCHÜTTPELZ THOMAS HUSER WOLFRAM SCHENCK | 2021 | Photonics Research2021，9，5： | 11 |
| 14 | Echo-enhanced ultrasound with pulse inversion imaging: A new imaging modality for the differentiation of cystic pancreatic tumours显示文摘瞄准:在膀胱的胰腺的损害的鉴别诊断描述并且讨论提高回响的 sonography。方法:脉搏倒置技术(与 2.4 mL SonoVue 的静脉注射) 或在第二泛音成像的条件下面的 power-Doppler 模式(与 4 g Levovist 的静脉注射) 被用于提高回响的 sonography。结果:Cystadenomas 经常沿着纤维变性海滨显示出许多容器。在另一方面,包囊腺癌是糟糕并且混乱 vascularized。“年轻假包囊”经常被发现有一面高度脉管的 ised 墙。然而,“旧假包囊”的墙是糟糕 vascularized。从未来的研究的数据证明基于这些成像标准,在膀胱的胰腺的群众的区别的提高回响的 sonography 的敏感和特性是 >90% 。结论:膀胱的胰腺的群众在提高回响的 sonography 有一个不同血管形成模式。这些特征为他们的鉴别诊断是有用的,但是组织学仍然是标准答案。 | Steffen Rickes Klaus Mnkemüller Peter Malfertheiner | 2006 | World Journal of Gastroenterology2006，12，14： | 10 |
| 15 | 内生真菌印度梨形孢诱导提高玉米苗期抗旱性研究初探显示文摘采用盆栽试验,初步研究内生真菌印度梨形孢诱导提高玉米抗旱性的效应。结果显示,在自然干旱胁迫下,根长、根鲜重、根干重、叶片数、叶面积、叶绿素含量等指标接种印度梨形孢的玉米幼苗比未接种的明显增加,差异达到显著、极显著水平;根干重、叶绿素含量等性状,接种印度梨形孢干旱胁迫处理的幼苗显著地高于未接种干旱处理,表明印度梨形孢真菌具有促进玉米幼苗生长的作用,能有效增强玉米幼苗的抗旱性。 | 张文英 蒿若超 汪嫒嫒 杨婷 Ralf Oelmüller | 2013 | 玉米科学2013，21，5： | 10 |
| 16 | Global kinematics of tectonic plates and subduction zones since the late Paleozoic Era显示文摘Detailed global plate motion models that provide a continuous description of plate boundaries through time are an effective tool for exploring processes both at and below the Earth's surface. A new generation of numerical models of mantle dynamics pre-and post-Pangea timeframes requires global kinematic descriptions with full plate reconstructions extending into the Paleozoic(410 Ma). Current plate models that cover Paleozoic times are characterised by large plate speeds and trench migration rates because they assume that lowermost mantle structures are rigid and fixed through time. When used as a surface boundary constraint in geodynamic models, these plate reconstructions do not accurately reproduce the present-day structure of the lowermost mantle. Building upon previous work, we present a global plate motion model with continuously closing plate boundaries ranging from the early Devonian at 410 Ma to present day.We analyse the model in terms of surface kinematics and predicted lower mantle structure. The magnitude of global plate speeds has been greatly reduced in our reconstruction by modifying the evolution of the synthetic Panthalassa oceanic plates, implementing a Paleozoic reference frame independent of any geodynamic assumptions, and implementing revised models for the Paleozoic evolution of North and South China and the closure of the Rheic Ocean. Paleozoic(410-250 Ma) RMS plate speeds are on average ~8 cm/yr, which is comparable to Mesozoic-Cenozoic rates of ~6 cm/yr on average.Paleozoic global median values of trench migration trend from higher speeds(~2.5 cm/yr) in the late Devonian to rates closer to 0 cm/yr at the end of the Permian(~250 Ma), and during the Mesozoic-Cenozoic(250-0 Ma) generally cluster tightly around ~1.1 cm/yr. Plate motions are best constrained over the past 130 Myr and calculations of global trench convergence rates over this period indicate median rates range between 3.2 cm/yr and 12.4 cm/yr with a present day median rate estimated at~5 cm/yr. For Paleozoic times(410-251 Ma) our model results in median convergence rates largely~5 cm/yr. Globally,~90% of subduction zones modelled in our reconstruction are determined to be in a convergent regime for the period of 120-0 Ma. Over the full span of the model, from 410 Ma to 0 Ma,~93% of subduction zones are calculated to be convergent, and at least 85% of subduction zones are converging for 97% of modelled times. Our changes improve global plate and trench kinematics since the late Paleozoic and our reconstructions of the lowermost mantle structure challenge the proposed fixity of lower mantle structures, suggesting that the eastern margin of the African LLSVP margin has moved by as much as ~1450 km since late Permian times(260 Ma). The model of the plate-mantle system we present suggests that during the Permian Period, South China was proximal to the eastern margin of the African LLSVP and not the western margin of the Pacific LLSVP as previous thought. | Alexander Young Nicolas Flament Kayla Maloney Simon Williams Kara Matthews Sabin Zahirovic R.Dietmar Müller | 2019 | Geoscience Frontiers2019，10，3： | 10 |
| 17 | Endoscopic papillectomy: Data of a prospective observational study显示文摘AIM:To investigate the clinical value of endoscopic papillectomy indicated by feasibility and safety of the procedure in various diseases of the papilla in a representative number of patients in a setting of daily clinical and endoscopic practice and care by means of a systematic prospective observational study. METHODS:Through a defined time period, all consecutive patients with tumor-like lesions of the papilla, who were considered for papillectomy, were enrolled in this systematic bicenter prospective observational study, and subdivided into 4 groups according to endoscopic and endoscopic ultrasonography (EUS) findings as well as histopathological diagnosis:adenoma; carcinoma/ neuroendocrine tumor (NET)/lymphoma; papilla into which catheter can not be introduced; adenomyomatosis, respectively. Treatment results and outcome were characterized by R0 resection, complication, recurrence rates and tumor-free survival.RESULTS:Over a 7-year period, 58 patients underwent endoscopic papillectomy. Main symptoms prompting to diagnostic measures were unclear abdominal pain in 50% and cholestasis with and without pain in 44%. Overall, 54/58 patients [inclusion rate, 93.1%; sex ratio, males/females = 25/29 (1:1.16); mean age, 65 (range, 22-88) years] were enrolled in the study. Prior to papillectomy, EUS was performed in 79.6% (n = 43/54). Group 1 (adenoma, n = 24/54; 44.4%):91.6% (n = 22/24) with R0 resection; tumor-free survival after a mean of 18.5 mo, 86.4% (n = 19/22); recurrence, 13.6% (n = 3/22); minor complications, 12.5% (n = 3/24). Group 2 (carcinoma/NET/lymphoma, n = 18/54; 33.3%):75.0% (n = 10/18) with R0 resection; tumor-free survival after a mean of 18.5 (range, 1-84) mo, 88.9% (n = 8/9); recurrence, 11.1% (n = 1/9). Group 3 (adenomyomatosis, n = 4/54; 7.4%). Group 4 (primarily no introducible catheter into the papilla, n = 8; 14.8%). The overall complication rate was 18.5% (n = 10/54; 1 subject with 2 complications):Bleeding, n = 3; pancreatitis, n = 7; perforation, n = 1 (intervention-related mortality, 0%). In summary, EUS is a sufficient diagnostic tool to preoperatively clarify diseases of the papilla including suspicious tumor stage in conjunction with postinterventional histopathological investigation of a specimen. Endoscopic papillectomy with curative intention is a feasible and safe approach to treat adenomas of the papilla. In high-risk patients with carcinoma of the papilla with no hints of deep infiltrating tumor growth, endoscopic papillectomy can be considered a reasonable treatment option with low risk and an approximately 80% probability of no recurrence if an R0 resection can be achieved. In patients with jaundice and in case the catheter can not be introduced into the papilla, papillectomy may help to get access to the bile duct. CONCLUSION:Endoscopic papillectomy is a challenging interventional approach but a suitable patientand local finding-adapted diagnostic and therapeutic tool with adequate risk-benefit ratio in experienced hands. | Uwe Will Anne-Kathrin Müller Frank Fueldner Igor Wanzar Frank Meyer | 2013 | World Journal of Gastroenterology2013，19，27： | 10 |
| 18 | Blood pressure gradients in cerebral arteries:a clue to pathogenesis of cerebral small vessel disease显示文摘rationale The role of hypertension in cerebral small vessel disease is poorly understood.At the base of the brain(the‘vascular centrencephalon’),short straight arteries transmit blood pressure directly to small resistance vessels;the cerebral convexity is supplied by long arteries with many branches,resulting in a drop in blood pressure.Hypertensive small vessel disease(lipohyalinosis)causes the classically described lacunar infarctions at the base of the brain;however,periventricular white matter intensities(WMIs)seen on MRI and WMI in subcortical areas over the convexity,which are often also called‘lacunes’,probably have different aetiologies.Objectives We studied pressure gradients from proximal to distal regions of the cerebral vasculature by mathematical modelling.Methods and results Blood flow/pressure equations were solved in an Anatomically Detailed Arterial Network(ADAN)model,considering a normotensive and a hypertensive case.Model parameters were suitably modified to account for structural changes in arterial vessels in the hypertensive scenario.Computations predict a marked drop in blood pressure from large and medium-sized cerebral vessels to cerebral peripheral beds.When blood pressure in the brachial artery is 192/113 mm Hg,the pressure in the small arterioles of the posterior parietal artery bed would be only 117/68 mm Hg.In the normotensive case,with blood pressure in the brachial artery of 117/75 mm Hg,the pressure in small parietal arterioles would be only 59/38 mm Hg.conclusion These findings have important implications for understanding small vessel disease.The marked pressure gradient across cerebral arteries should be taken into account when evaluating the pathogenesis of small WMIs on MRI.Hypertensive small vessel disease,affecting the arterioles at the base of the brain should be distinguished from small vessel disease in subcortical regions of the convexity and venous disease in the periventricular white matter. | Pablo J Blanco Lucas O Müller J David Spence | 2017 | Stroke & Vascular Neurology2017，2，3： | 9 |
| 19 | Use of butyrate or glutamine in enema solution reduces inflammation and fibrosis in experimental diversion colitis显示文摘AIM:To investigate whether butyrate or glutamine enemas could diminish inflammation in experimental diversion colitis.METHODS:Wistar specific pathogen-free rats were submitted to a Hartmann's end colostomy and treated with enemas containing glutamine,butyrate,or saline.Enemas were administered twice a week in the excluded segment of the colon from 4 to 12 wk after the surgical procedure.Follow-up colonoscopy was performed every 4 wk for 12 wk.The effect of treatment was evaluated using video-endoscopic and histologic scores and measuring interleukin-1β,tumor necrosis factor-alpha,and transforming growth factor beta production in organ cultures by enzyme linked immunosorbent assay.RESULTS:Colonoscopies of the diverted segment showed mucosa with hyperemia,increased number of vessels,bleeding and mucus discharge.Treatment with either glutamine or butyrate induced significant reductions in both colonoscopic(P < 0.02) and histological scores(P < 0.01) and restored the densities of collagen fibers in tissue(P = 0.015;P = 0.001),the number of goblet cells(P = 0.021;P = 0.029),and the rate of apoptosis within the epithelium(P = 0.043;P = 0.011) to normal values.The high levels of cytokines in colon explants from rats with diversion colitis significantly decreased to normal values after treatment with butyrate or glutamine.CONCLUSION:The improvement of experimental diversion colitis following glutamine or butyrate enemas highlights the importance of specific luminal nutrients in the homeostasis of the colonic mucosa and supports their utilization for the treatment of human diversion colitis. | Rodrigo Goulart Pacheco Christiano Costa Esposito Lucas CM Müller Morgana TL Castelo-Branco Leonardo Pereira Quintella Vera Lucia A Chagas Heitor Siffert P de Souza Alberto Schanaider | 2012 | World Journal of Gastroenterology2012，18，32： | 9 |
| 20 | Bifurcation and Chaos Analysis of Nonlinear Rotor System with Axial-grooved Gas-lubricated Journal Bearing Support显示文摘Axial-grooved gas-lubricated journal bearings have been widely applied to precision instrument due to their high accuracy, low friction, low noise and high stability. The rotor system with axial-grooved gas-lubricated journal bearing support is a typical nonlinear dynamic system. The nonlinear analysis measures have to be adopted to analyze the behaviors of the axial-grooved gas-lubricated journal bearing-rotor nonlinear system as the linear analysis measures fail. The bifurcation and chaos of nonlinear rotor system with three axial-grooved gas-lubricated journal bearing support are investigated by nonlinear dynamics theory. A time-dependent mathematical model is established to describe the pressure distribution in the axial-grooved compressible gas-lubricated journal bearing. The time-dependent compressible gas-lubricated Reynolds equation is solved by the differential transformation method. The gyroscopic effect of the rotor supported by gas-lubricated journal bearing with three axial grooves is taken into consideration in the model of the system, and the dynamic equation of motion is calculated by the modified Wilson-θ-based method. To analyze the unbalanced responses of the rotor system supported by finite length gas-lubricated journal bearings, such as bifurcation and chaos, the bifurcation diagram, the orbit diagram, the Poincaré map, the time series and the frequency spectrum are employed. The numerical results reveal that the nonlinear gas film forces have a significant influence on the stability of rotor system and there are the rich nonlinear phenomena, such as the periodic, period-doubling, quasi-periodic, period-4 and chaotic motion, and so on. The proposed models and numerical results can provide a theoretical direction to the design of axial-grooved gas-lubricated journal bearing-rotor system. | ZHANG Yongfang HEI Di Lü Yanjun WANG Quandai MüLLER Norbert | 2014 | Chinese Journal of Mechanical Engineering2014，27，2： | 9 |
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