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2069篇 您的检索式:作者名="Lenz"
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1Intraductal ultrasound substantiates diagnostics of bile duct strictures of uncertain etiology显示文摘AIM:To report the largest patient cohort study investigating the diagnostic yield of intraductal ultrasound (IDUS) in indeterminate strictures of the common bile duct.METHODS:A patient cohort with bile duct strictures of unknown etiology was examined by IDUS.Sensitivity,specificity and accuracy rates of IDUS were calculated relating to the definite diagnoses proved by histopathology or long-term follow-up in those patients who did not undergo surgery.Analysis of the endosonographic report allowed drawing conclusions with respect to the T and N staging in 147 patients.IDUS staging was compared to the postoperative histopathological staging data allowing calculation of sensitivity,specificity and accuracy rates for T and N stages.The endoscopic retrograde cholangio-pancreatography and IDUS procedures were performed under fluoroscopic guidance using a side-viewing duodenoscope (Olympus TJF 160,Olympus,Ltd.,Tokyo,Japan).All procedures were performed under conscious sedation (propofol combined with pethidine) according to the German guidelines.For IDUS,a 6 F or 8 F ultrasound miniprobe was employed with a radial scanner of 15-20 MHz at the tip of the probe (Aloka Co.,Tokyo,Japan).RESULTS:A total of 397 patients (210 males,187 females,mean age 61.43 ± 13 years) with indeterminate bile duct strictures were included.Two hundred and sixty-four patients were referred to the department of surgery for operative exploration,thus surgical histopathological correlation was available for those patients.Out of 264 patients,174 had malignant disease proven by surgery,in 90 patients benign disease was found.In these patients decision for surgical exploration was made due to suspicion for malignant disease in multimodal diagnostics (computed tomography scan,endoscopic ultrasound or magnetic resonance imaging).Twenty benign bile duct strictures were misclassified by IDUS as malignant while 14 patients with malignant strictures were initially misdiagnosed by IDUS as benign resulting in sensitivity,specificity and accuracy ratesof 93.2%,89.5% and 91.4%,respectively.In the subgroup analysis of malignancy prediction,IDUS showed best performance in cholangiocellular carcinoma as underlying disease (sensitivity rate,97.6%) followed by pancreatic carcinoma (93.8%),gallbladder cancer (88.9%) and ampullary cancer (80.8%).A total of 133 patients were not surgically explored.32 patients had palliative therapy due to extended tumor disease in IDUS and other imaging modalities.Ninety-five patients had benign diagnosis by IDUS,forceps biopsy and radiographic imaging and were followed by a surveillance protocol with a follow-up of at least 12 mo;the mean follow-up was 39.7 mo.Tumor localization within the common bile duct did not have a significant influence on prediction of malignancy by IDUS.The accuracy rate for discriminating early T stage tumors (T1) was 84% while for T2 and T3 malignancies the accuracy rates were 73% and 71%,respectively.Relating to N0 and N1 staging,IDUS procedure achieved accuracy rates of 69% for N0 and N1,respectively.Limitations:Pretest likelihood of 52% may not rule out bias and overinterpretation due to the clinical scenario or other prior performed imaging tests.CONCLUSION:IDUS shows good results for accurate diagnostics of bile duct strictures of uncertain etiology thus allowing for adequate further clinical management.Tobias Meister Hauke S Heinzow Carina Woestmeyer Philipp Lenz Josef Menzel Torsten Kucharzik Wolfram Domschke Dirk Domagk 2013World Journal of Gastroenterology2013,19,6:19
2Clinical outcome and predictors of survival after TIPS insertion in patients with liver cirrhosis显示文摘AIM:To determine the clinical outcome and predictors of survival after transjugular intrahepatic portosystemic stent shunt (TIPS) implantation in cirrhotic patients. METHODS:Eighty-one patients with liver cirrhosis and consequential portal hypertension had TIPS implantation (bare metal) for either refractory ascites (RA) (n= 27) or variceal bleeding (VB) (n = 54). Endpoints for the study were:technical success, stent occlusion and stent stenosis, rebleeding, RA and mortality. Clinical records of patients were collected and analysed. Baseline characteristics [e.g., age, sex, CHILD score and the model for end-stage liver disease score (MELD score), underlying disease] were retrieved. The Kaplan-Meier method was employed to calculate survival from the time of TIPS implantation and comparisons were made by log rank test. A multivariate analysis of factors influencing survival was carried out using the Cox proportional hazards regression model. Results were expressed as medians and ranges. Comparisons between groups were performed by using the Mann-Whitney Utest and the χ 2 test as appropriate. RESULTS:No difference could be seen in terms of age, sex, underlying disease or degree of portal pressure gradient (PPG) reduction between the ascites and the bleeding group. The PPG significantly decreased from 23.4 ± 5.3 mmHg (VB) vs 22.1 ± 5.5 mmHg (RA) before TIPS to 11.8 ± 4.0 vs 11.7 ± 4.2 after TIPS implantation (P = 0.001 within each group). There was a tendency towards more patients with stage CHILD A in the bleeding group compared to the ascites group (24 vs 6, P = 0.052). The median survival for the ascites group was 29 mo compared to > 60 mo for the bleeding group (P = 0.009). The number of radiological controls for stent patency was 6.3 for bleeders and 3.8 for ascites patients (P = 0.029). Kaplan-Meier calculation indicated that stent occlusion at first control (P = 0.027), ascites prior to TIPS implantation (P = 0.009), CHILD stage (P = 0.013), MELD score (P = 0.001) and those patients not having undergone liver transplantation (P = 0.024) were significant predictors of survival. In the Cox regression model, stent occlusion (P = 0.022), RA (P = 0.043), CHILD stage (P = 0.015) and MELD score (P = 0.004) turned out to be independent prognostic factors of survival. The anticoagulation management (P = 0.097), the porto-systemic pressure gradient (P= 0.460) and rebleeding episodes (P = 0.765) had no significant effect on the overall survival. CONCLUSION:RA, stent occlusion, initial CHILD stage and MELD score are independent predictors of survival in patients with TIPS, speaking for a close follow-up in these circumstances.Hauke S Heinzow Philipp Lenz Michael Khler Frank Reinecke Hansjrg Ullerich Wolfram Domschke Dirk Domagk Tobias Meister 2012World Journal of Gastroenterology2012,18,37:17
3Regorafenib monotherapy for previously treated metastatic colorectal cancer (CORRECT): an international, multicentre, randomised, placebo-controlled, phase 3 trial显示文摘Axel Grothey Eric Van Cutsem Alberto Sobrero Salvatore Siena Alfredo Falcone Marc Ychou Yves Humblet Olivier Bouché Laurent Mineur Carlo Barone Antoine Adenis Josep Tabernero Takayuki Yoshino Heinz-Josef Lenz Richard M Goldberg Daniel J Sargent Frank Ciho 2012The Lancet2012,,:10
4Acute necrotizing pancreatitis as fi rst manifestation of primary hyperparathyroidism显示文摘We report the case of a female patient with severe acute necrotizing pancreatitis associated with hypercalcemia as first manifestation of primary hyperparathyroidism caused by a benign parathyroid adenoma.Initially the acute pancreatitis was treated conservatively.The patient subsequently underwent surgical resection of the parathyroid adenoma and surgical clearance of a large infected pancreatic pseudocyst.Although the association of parathyroid adenoma-induced hypercalcemia and acute pancreatitis is a known medical entity,it is very uncommon.The pathophysiology of hypercalcemia-induced acute pancreatitis is therefore not well known,although some mechanisms have been proposed.It is important to treat the provoking factor.Therefore,the cause of hypercalcemia should be identif ied early.Surgical resection of the parathyroid adenoma is the ultimate therapy.Jeroen I Lenz Jimmy M Jacobs Bart Op de Beeck Ivan A Huyghe Paul A Pelckmans Tom G Moreels 2010World Journal of Gastroenterology2010,16,23:9
5Comparative analysis of clinicopathological correlations of cyclooxygenase-2 expression in resectable pancreatic cancer显示文摘AIM:To perform a comparative analysis of clinicopathological correlations of cyclooxygenase2 (COX2) expression in pancreatic cancer, examined by monoclonal and polyclonal antibodies.METHODS: The COX2 expression in 85 resection specimens of pancreatic ductal adenocarcinoma was immunohistochemically examined using both monoclonal and polyclonal antibodies. The final immunoscores were obtained by multiplying the percentage of positive cells with the numeric score reflecting the staining intensity.COX2 expression levels were classified into three categories (0, 1+, and 2+) and the clinicopathological correlations were statistically evaluated and analyzed.RESULTS: The positive tumor expression rates of COX2 were 80.5% using monoclonal antibody and 69.4% using polyclonal antibody. In the KaplanMeier analysis, no significant correlations were found between levels of COX2 expression and overall survival (OS), but trends to longer OS were found in COX2 negative cases using monoclonal antibody. Significantly longer disease free survival was revealed in COX2 negative cases using monoclonal antibody (P = 0.019). No correlations between COX2 expression levels and grade (G), tumor (T) status and nodal (N) status were demonstrated. Low histological grade showed a strong association with a longer OS (P < 0.001). Correlation of survival and T status revealed a shorter OS in T3 tumors, but the results reached only marginal statistical significance (P = 0.070). In the multivariate Cox proportional hazards regression model, histological grade, T and N status remained valuable predictors of a worse survival with borderline significance for T [hazards ratio (HR) = 4.18 for G (if G = 3, P < 0.001); HR = 1.64 for T (if T = 3, P = 0.065); HR = 2.53 for N (if N = 1, P = 0.006)]. Higher grade, T or N status was associated with a worse OS. CONCLUSION: The immunohistochemically assessed level of COX2 expression does not seem to represent a valuable independent prognostic factor and is not superior to the conventional prognostic factors.Marketa Hermanova Petr Karasek Jiri Tomasek Jiri Lenz Jiri Jarkovsky Petr Dite 2010World Journal of Gastroenterology2010,16,15:7
6Chronic radiation proctopathy: A practical review of endoscopic treatment显示文摘Chronic radiation proctopathy(CRP) is a troublesome complication of pelvic radiotherapy. The most common presentation is rectal bleeding. CRP symptoms interfere with daily activities and decrease quality of life. Rectal bleeding management in patients with CRP represents a conundrum for practitioners. Medical therapy is ineffective in general and surgical approach has a high morbidmortality. Endoscopy has a role in the diagnosis,staging and treatment of this disease. Currently available endoscopic modalities are formalin,potassium titanyl phosphate laser,neodymium:yttrium-aluminum-garnet laser,argon laser,bipolar electrocoagulation(BiCAP),heater probe,band ligation,cryotherapy,radiofrequency ablation and argon plasma coagulation(APC). Among these options,APC is the most promising.Luciano Lenz Rachel Rohr Frank Nakao Ermelindo Libera Angelo Ferrari 2016World Journal of Gastrointestinal Surgery2016,8,2:7
7Colon capsule endoscopy versus standard colonoscopy in assessing disease activity of ulcerative colitis: a prospective trial显示文摘T. Meister H. S. Heinzow D. Domagk A. Dortgolz F. Lenze M. Ross W. Domschke A. Lügering 2013Techniques in Coloproctology2013,,6:4
8Assessment of stricturing Crohn's disease:Current clinicalpractice and future avenues显示文摘Crohn's disease(CD) is a chronic remittent idiopathic disease. Although the early phase of the disease is commonly characterized by inflammation-driven symptoms, such as diarrhea, the frequency of fibrostenotic complications in patients with CD increases over the long-term course of the disease. This review presents the current diagnostic options for assessing CD-associated strictures. In addition to the endoscopic evaluation of CD strictures, this review summarizes the currently available imaging modalities, including ultrasound and cross-sectional imaging techniques. In addition to stricture detection, differentiating between the primarily inflammatory strictures and the predominantly fibrotic ones is essential for selecting the appropriate treatment strategy(anti-inflammatory medical treatment vs endoscopical or surgical approaches). Therefore, recent imaging advances, such as contrast-enhanced ultrasound and ultrasound elastography, contribute to the development of noninvasive non-radiating imaging of CD-associated strictures. Finally, novel magnetic resonance imaging techniques, such as diffusion-weighted, motility and magnetization transfer imaging, as well as 18F-FDG PET/CT, molecular imaging approaches and biomarkers, are critically reviewed with regard to their potential role in assessing stricturing CD.Dominik Bettenworth Tobias M Nowacki Friederike Cordes Boris Buerke Frank Lenze 2016World Journal of Gastroenterology2016,22,3:4
9Detection and characterization of murine colitis and carcinogenesis by molecularly targeted contrast-enhanced ultrasound显示文摘AIM To study mucosal addressin cellular adhesion molecule-1(MAd CAM-1) and vascular endothelial growth factor(VEGF)-targeted contrast enhanced ultrasound(CEUS) for the assessment of murine colitis and carcinogenesis. METHODS C57BL/6 mice were challenged with 3% dextran sodium-sulfate(DSS) for three, six or nine days to study the development of acute colitis. Ultrasound was performed with and without the addition of unspecific contrast agents. MAd CAM-1-targeted contrast agent was used to detect and quantify MAd CAM-1 expression. Inflammatory driven colorectal azoxymethane(AOM)/DSS-induced carcinogenesis was examined on day 42 and 84 using VEGF-targeted contrast agent. Highly specific tissue echogenicity was quantified using specialized software. Sonographic findings were correlated to tissue staining, western blot analysis and immunohistochemistry to quantify the degree of inflammation and stage of carcinogenesis. RESULTS Native ultrasound detected increased general bowel wall thickening that correlated with more progressed and more severe DSS-colitis(healthy mice: 0.3 mm ± 0.03 vs six days DSS: 0.5 mm ± 0.2 vs nine days DSS: 0.6 mm ± 0.2, P < 0.05). Moreover, these sonographic findings correlated well with clinical parameters such as weight loss(r2 = 0.74) and histological damage(r2 = 0.86)(P < 0.01). In acute DSS-induced murine colitis, CEUS targeted against MAd CAM-1 detected and differentiated stages of mild, moderate and severe colitis via calculation of mean pixel contrast intensity in decibel(9.6 d B ± 1.6 vs 12.9 d B ± 1.4 vs 18 d B ± 3.33, P < 0.05). Employing the AOM/DSSinduced carcinogenesis model, tumor development was monitored by CEUS targeted against VEGF and detected a significantly increased echogenicity in tumors as compared to adjacent healthy mucosa(healthy mucosa, 1.6 d B ± 1.4 vs 42 d, 18.2 d B ± 3.3 vs 84 d, 18.6 d B ± 4.9, P < 0.01). Tissue echogenicity strongly correlated with histological analysis and immunohistochemistry findings(VEGF-positive cells in 10 high power fields of healthy mucosa: 1 ± 1.2 vs 42 d after DSS start: 2.4 ± 1.6 vs 84 d after DSS start: 3.5 ± 1.3, P < 0.01). CONCLUSION Molecularly targeted CEUS is a highly specific and noninvasive imaging modality, which characterizes murine intestinal inflammation and carcinogenesis in vivo.Markus Brückner Jan Heidemann Tobias M Nowacki Friederike Cordes Jorg Stypmann Philipp Lenz Faekah Gohar Andreas Lügering Dominik Bettenworth 2017World Journal of Gastroenterology2017,23,16:4
10Colorectal cancer显示文摘David Cunningham Wendy Atkin Heinz-Josef Lenz Henry T Lynch Bruce Minsky Bernard Nordlinger Naureen Starling 2010The Lancet2010,,9719:3
11Molecular Pathways: Estrogen Pathway in Colorectal Cancer显示文摘Afsaneh Barzi Annika Medea Lenz Melissa J. Labonte Heinz-Josef Lenz 2013Clinical Cancer Research2013,,21:3
12Targeting IL-8 in colorectal cancer显示文摘Yan Ning Heinz-Josef Lenz 2012Expert Opinion on Therapeutic Targets2012,,5:2
13A Comparison of Intravenous Oxycodone and Intravenous Morphine in Patient-Controlled Postoperative Analgesia After Laparoscopic Hysterectomy显示文摘Harald Lenz Leiv Sandvik Erik Qvigstad Carl Eivind Bjerkelund Johan Raeder 2009Anesthesia & Analgesia2009,,4:2
14Effects of COX inhibition on experimental pain and hyperalgesia during and after remifentanil infusion in humans显示文摘Harald Lenz Johan Raeder Tomas Draegni Fridtjof Heyerdahl Martin Schmelz Audun Stubhaug 2011Pain2011,,6:2
15Prospective observational multicenter study to define a diagnostic algorithm for biliary candidiasis显示文摘AIM:To develop an algorithm to improve the diagnosis and treatment of patients with biliary candidiasis.METHODS:We performed a prospective study of 127patients who underwent endoscopic retrograde cholangiopancreatography,for various biliary disorders,at 3 tertiary referral centers in Germany from July 2011through July 2012(ClinicalTrials.gov:NCT01109550).Bile,buccal,and stool samples were collected.When indicated,endoscopic transpapillary bile duct biopsies were performed to clarify the etiology of bile duct strictures and to prove invasive fungal infections.RESULTS:Candida species were detected in 38 of the 127 bile samples(29.9%).By multivariate analysis patients’age and previous endoscopic sphincterotomy were independent risk factors for biliary candidiasis(P<0.05).Patients with immunosuppression(P=0.058)and recent long-term antibiotic therapy(>7 d)(P=0.089)tend to be at risk for biliary candidiasis.One patient was negative in mycological culture of bile fluid but invasive biliary candidiasis was diagnosed histologically.Of Candida subspecies detected,36.7%were azole-resistant,such as C glabrata.Eight patients received anti-mycotic therapy,based on our algorithm.Of these,3 had cancer with biliary tract involvement,2had secondary sclerosing cholangitis,1 had retroperitoneal fibrosis,and 5 had septicemia.In all patients contamination was ruled out by smears of the endoscope channel.CONCLUSION:Gastroenterologists should be aware of frequent candida colonization in patients with cholangitis and biliary disorders.Our suggested algorithm facilitates the further clinical management.Philipp Lenz Franziska Eckelskemper Thomas Erichsen Tim Lankisch Alexander Dechêne Gabriele Lubritz Frank Lenze Torsten Beyna Hansjorg Ullerich Andre Schmedt Dirk Domagk 2014World Journal of Gastroenterology2014,20,34:2
16Parametrically constrained geometry relaxations for high-throughput materials science显示文摘Reducing parameter spaces via exploiting symmetries has greatly accelerated and increased the quality of electronic-structure calculations.Unfortunately,many of the traditional methods fail when the global crystal symmetry is broken,even when the distortion is only a slight perturbation(e.g.,Jahn-Teller like distortions).Here we introduce a flexible and generalizable parametric relaxation scheme and implement it in the all-electron code FHI-aims.This approach utilizes parametric constraints to maintain symmetry at any level.After demonstrating the method’s ability to relax metastable structures,we highlight its adaptability and performance over a test set of 359 materials,across 13 lattice prototypes.Finally we show how these constraints can reduce the number of steps needed to relax local lattice distortions by an order of magnitude.The flexibility of these constraints enables a significant acceleration of high-throughput searches for novel materials for numerous applications.Maja-Olivia Lenz Thomas A.R.Purcell David Hicks Stefano Curtarolo Matthias Scheffler Christian Carbogno 2019npj Computational Materials2019,,1:2
17POLY (β-HYDROXYALKANOATES): NATURAL BIOCOMPATIBLE AND BIODEGRADABLE POLYESTERS PRODUCED BY BACTERIA显示文摘A wide variety of different types of microorganisms are known to produce intracellular energy and carbon storage products, which have been generally described as being poly (β-hydroxybutyrate), PHB, but which are, more often than not, copolymers containing different alkyl groups at the β-position. Hence, PHB belongs to the family ofpoly (β-hydroxyalkanoastes), PHA, all of which are usually formed as intracellular inclusions in bacteria under unbalanced growth conditions. Recently, it became of industrial interest to evaluate these PHA polyesters as natural biodegradable and biocompatible plastics for a wide range of possible applications, such as surgical sutures or packaging containers. For industrial applications, the controlled incorporation of repeating units with different chain lengths into a series of copolymers is desirable in order to produce polyesters with a range of material properties because physical and chemical characteristics depend strongly on the polymer composition. Such 'tailor-made' copolymers can be produced under controlled growth conditions in that, if a defined mixture of substrates for a certain type of microorganisms is supplied, a well defined and reproducible copolymer is formed.ROBERT W. LENZ RICHARD A. GROSS HELMUT BRANDL R. CLINTON FULLER 1989Chinese Journal of Polymer Science1989,7,4:2
18大气CO_2富集对根际NaCl盐渍的人参果植株干物质生产和水分利用的影响显示文摘对单株砂培盆栽的半木质化枝条扦插生根的一月龄人生果(Solanum muricatum Ait.)栽培品种'Xotus',每周浇两次200mL NaCl质量浓度分别为0mg·L-1和25mg·L-1的Hoagland营养液处理2个月,第二个月在控制空气CO2体积分数为(350±10)×10-6、(700±10)×10-6和(1050±10)×10-6的植物生长箱内试验。结果表明,人参果植株干物质生产量和耗水量受根际NaCl盐渍而下降,又随大气CO2升高而增加。根际NaCl盐渍能增大植株叶片蒸腾系数、根/冠比和干物质向枝干和根部分配的比例及积累量,降低根系吸收水分的效率和耗水量。升高大气CO2能促进叶片发育及干物质向地上部其他器官和地下部组织分配,增加总叶面积、比叶干重和各种器官中干物质增长量,提高干物质生产率和水分利用率。根际经25mg·L-1NaCl盐渍处理的植株,总干物质增长量和水分利用率相应下降50%~54%和24%~37%;与350×10-6CO2的处理的植株相比,700×10-6及1050×10-6CO2的处理分别使这两项指标提高到79%~106%和61%~88%以及133%~189%和99%~142%。大气CO2富集能改善受NaCl盐渍的植株干物质生产力、提高水分利用率。根际NaCl盐渍和大气CO2富集对人参果植株干物质生产和水分利用有生物互作效应。它们的共同作用会促进植株干物质的增长及叶片中合成的干物质向其他器官分配,提高干物质生产率和水分利用率,同时减少总叶面积、枝条和根系干重、根系吸水效率、植株耗水量和叶片蒸腾系数。因此,全球大气CO2富集将有利于该作物的干物质生产和水分利用。陈凯 胡国谦 KEUTGEN Norbert KEUTGEN Anna JANSSENS Marc LENZ Fritz 2012大气科学学报2012,35,2:2
19Double- vs. single-balloon vs. spiral enteroscopy显示文摘Philipp Lenz Dirk Domagk 2012Best Practice & Research Clinical Gastroenterology2012,,3:2
20Colorectal cancer显示文摘David Cunningham Wendy Atkin Heinz-Josef Lenz Henry T Lynch Bruce Minsky Bernard Nordlinger Naureen Starling 2010The Lancet2010,,9719:2
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