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51.
Annekatrin Oehme Ulrich Gebauer Klaus Gehrke Peter Beyer Brigitte Hartmann M. Dieter Lechner 《Macromolecular chemistry and physics.》1994,195(12):3773-3781
The catalyst system Nd(octanoate)3/Al2Et3Cl3/Al(iBu)3 (Et: ethyl, iBu: isobutyl) in heptane for the polymerization of butadiene and isoprene was examined. The concentration of Al2Et3Cl3, Al(iBu)3 and the order of addition of the components were varied. The results of the determination of conversion, microstructure, molar mass and molar mass distribution are illustrated. The optimum component concentration ratio (Nd(octanoate)3/Al2Et3Cl3/Al(iBu)3 = 1 : 1,5 : 25) at a catalyst concentration of 1,0 mmol Nd/L was fixed and used for the copolymerization of butadiene and isoprene. Copolymers obtained under various monomer feed ratios were characterized by 1H, 13C NMR spectroscopy, gel-permeation chromatography (GPC), and differential scanning calorimetry (DSC) investigations. 相似文献
52.
Benjamin Babic Dolores T M ller Florian Gebauer Lars Mortimer Schiffmann Rabi R Datta Wolfgang Schr der Christiane J Bruns Jessica M Leers Hans F Fuchs 《World journal of gastrointestinal oncology》2021,13(6):612-624
BACKGROUNDThere is no established correlation between 24-h esophageal pH-metry (Eso-pH) and the new laryngopharyngeal pH-monitoring system (Restech) as only small case series exist. Eso-pH was not designed to detect laryngopharyngeal reflux (LPR) and Restech may detect LPR better. We have previously published a dataset using the two techniques in a large patient collective with gastroesophageal reflux disease. Anatomically, patients after esophagectomy were reported to represent an ideal human reflux model as no reflux barrier exists. AIMTo use a human reflux model to examine our previously published correlation in these patients. METHODSPatients after Ivor Lewis esophagectomy underwent our routine follow-up program with surveillance endoscopies, computed tomography scans and further exams following surgery. Only patients with a complete check-up program and reflux symptoms were offered inclusion into this prospective study and evaluated using Restech and simultaneous Eso-pH. Subsequently, the relationship between the two techniques was evaluatedRESULTSA total of 43 patients from May 2016 - November 2018 were included. All patients presented with mainly typical reflux symptoms such as heartburn (74%), regurgitation (84%), chest pain (58%), and dysphagia (47%). Extraesophageal symptoms such as cough, hoarseness, asthma symptoms, and globus sensation were also present. Esophageal 24-hour pH-metry was abnormal in 88% of patients with a mean DeMeester Score of 229.45 [range 26.4-319.5]. Restech evaluation was abnormal in 61% of cases in this highly selective patient cohort. All patients with abnormal supine LPR were also abnormal for supine esophageal reflux measured by conventional Eso-pH. CONCLUSIONPatients following esophagectomy and reconstruction with gastric interposition can ideally serve as a human reflux model. Interestingly, laryngopharyngeal reflux phases occur mainly in the upright position. In this human volume-reflux model, results of simultaneous esophageal and laryngopharyngeal (Restech) pH-metry showed 100% correlation as being explicable by one of our reflux scenarios. 相似文献
53.
Cardiac resynchronization therapy: a novel adjunct to the treatment and prevention of systemic right ventricular failure 总被引:1,自引:0,他引:1
Janousek J Tomek V Chaloupecký VA Reich O Gebauer RA Kautzner J Hucín B 《Journal of the American College of Cardiology》2004,44(9):1927-1931
OBJECTIVES: This study aimed to evaluate the technical feasibility and hemodynamic benefit of cardiac resynchronization therapy (CRT) in patients with systemic right ventricle (RV). BACKGROUND: Patients with a systemic RV are at high risk of developing heart failure. Cardiac resynchronization therapy may improve RV function in those with electromechanical dyssynchrony. METHODS: Eight patients (age 6.9 to 29.2 years) with a systemic RV and right bundle-branch block (n = 2) or pacing from the left ventricle (LV) (n = 6) with a QRS interval of 161 +/- 21 ms underwent CRT (associated with cardiac surgery aimed at decrease in tricuspid regurgitation in 3 of 8 patients) and were followed-up for a median of 17.4 months. RESULTS: Change from baseline rhythm to CRT was accompanied by a decrease in QRS interval (-28.0%, p = 0.002) and interventricular mechanical delay (-16.7%, p = 0.047) and immediate improvement in the RV filling time (+10.9%, p = 0.002), Tei index (-7.7%, p = 0.008), estimated RV maximum +dP/dt(+45.9%, p = 0.007), aortic velocity-time integral (+7.0%, p = 0.028), and RV ejection fraction by radionuclide ventriculography (+9.6%, p = 0.04). The RV fractional area of change increased from a median of 18.1% before resynchronization to 29.5% at last follow-up (p = 0.008) without a significant change in the end-diastolic area (+4.0%, p = NS). CONCLUSIONS: The CRT yielded improvement in systemic RV function in patients with spontaneous or LV pacing-induced electromechanical dyssynchrony and seems to be a promising adjunct to the treatment and prevention of systemic RV failure. 相似文献
54.
Jeremy A. Frimer Karl Aquino Jochen E. Gebauer Luke Zhu Harrison Oakes 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(21):6591-6594
Talking about helping others makes a person seem warm and leads to social approval. This work examines the real world consequences of this basic, social-cognitive phenomenon by examining whether record-low levels of public approval of the US Congress may, in part, be a product of declining use of prosocial language during Congressional debates. A text analysis of all 124 million words spoken in the House of Representatives between 1996 and 2014 found that declining levels of prosocial language strongly predicted public disapproval of Congress 6 mo later. Warm, prosocial language still predicted public approval when removing the effects of societal and global factors (e.g., the September 11 attacks) and Congressional efficacy (e.g., passing bills), suggesting that prosocial language has an independent, direct effect on social approval.As recently as 2002, public approval of Congress was reliably over 50% and as high as 84%. In late 2013, though, public approval reached an all-time low, with less than 10% of Americans expressing support (1). What caused this dramatic decline in public approval in just over a decade? One explanation is that the public held Congress responsible for societal and global problems (e.g., a weak economy) (2, 3). A second explanation is that the public disapproves of ineffective governance. For example, public approval of Congress tends to drop when Republicans and Democrats are polarized against one another and when Congress conflicts with the President (4, 5). We test a third explanation that has less to do with action and more to do with talk (6). We suggest that recent public disapproval partly resulted from the disappearance of warm, prosocial language in Congressional discourse.Previous experimental research has shown that presenting a warm and prosocial demeanor increases social approval (7). People reveal a wealth of information about their feelings and intentions through verbal communication (8–10). The speaker’s underlying motives notwithstanding, talking about helping others makes positive impressions upon an audience (11). We investigated whether this well-documented finding can explain public perceptions of Congress. Specifically, we asked whether the recent rise of public disapproval of Congress is predicted by declining prosocial language of elected representatives.To measure prosocial language, we computer analyzed all 123,927,807 words spoken in session of the US House of Representatives between 1996 and 2014. Our approach was to look for linguistic markers of prosocial language; we used content analysis software (12) to calculate the proportion of words in the target text that matched entries in a validated dictionary of prosocial words (13). We then compared levels of prosocial language within each month of Congress with their approval ratings by the American public (14) and found a striking match. Fig. 1 shows that levels of prosocial language and the public’s approval followed the same trajectory between 1996 and 2014, r(204) = 0.55, P < 0.001. Notably, the language of both Democrats, r(204) = 0.53, P < 0.001, and Republicans, r(204) = 0.54, P < 0.001, predicted the public’s approval of Congress.Open in a separate windowFig. 1.Prosocial language within the US Congress predicts the public’s approval of Congress. (A) Prosocial language represents the density of prosocial words in the in-session speeches of members of the US House of Representatives. (B) Public approval is Gallup survey data. Individual data points represent monthly scores. Solid lines connect 2-y session means.Public approval peaked in the aftermath of the September 11 attacks, declined over the next 7 y, rose slightly in the wake of the 2008 financial crisis, and then declined again. Prosocial language followed a nearly identical trajectory. In the years spanning 2002 and 2014, a small (19%) decrease in prosocial language ushered in a large (75%) decrease in public approval. The individual words whose use most strongly predicted public approval were as follows: gentle, involve, educate, contribute, concerned, give, tolerate, trust, and cooperate.The correlation between prosocial language and public approval does not necessarily imply that representatives’ language caused the public to approve of them. The reverse could be true: The public’s approval could cause changes in the topics that representatives raised. If one variable were causing the other, the causal factor would have changed first and the effected factor second. We tested which variable changed first in time by assessing the association between prosocial language in the present and public approval with time lags of up to 50 mo in the past and future (Fig. 2). The distribution of the associations across the time lags nearly perfectly fitted a normal distribution curve, r(98) = 0.97, P < 0.001. The maximum association between prosocial language and public approval was at +6.7 mo, meaning that what Congress says today best predicts their public approval ratings 29 wk into the future.Open in a separate windowFig. 2.Time-lagged associations between prosocial language and public approval of the US Congress. How representatives speak today best predicts their public approval ratings 6.7 mo into the future.Another concern with the present data is the possibility that some exogenous factor (e.g., the September 11 attacks) caused changes in both language and public approval. We reasoned that, if operative, societal and global factors would also have influenced the US President’s language and/or the economy. Alternatively, dysfunctional governance may cause both politicians’ rhetoric to be less civil and the public to disapprove (SI Text and Table S1). To test whether prosocial language has an independent, direct effect on the public sentiment, we ran a regression analysis in which we controlled for the effects of both societal/global factors (in the form of the President’s prosocial language, US unemployment rate, and US consumer expectations about the economy) and competent governance (in the form of partisan conflict, the number of bills that Congress passed, and Presidential vetoes). Even with these conservative controls, prosocial language within Congress still predicted the public’s approval (Multiple regression Predictor Zero-order r B β Societal and global factors President’s prosocial language 0.30**** 4.06 0.15*** Country unemployment -0.54**** −1.33 -0.16** Country economic expectations 0.63**** 0.17 0.16* Competent governance Partisan conflict in the House -0.48**** −0.18 -0.21*** Bills passed in the House -0.12* −0.06 -0.10* Presidential vetoes 0.04 −2.40 -0.09 Congressional rhetoric Congress’ prosocial language 0.55**** 21.56 0.35****