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61.
62.
K.J. Wirth E. Klaus H.C. Englert B.A. Schölkens W. Linz 《Naunyn-Schmiedeberg's archives of pharmacology》1999,360(3):295-300
Ventricular fibrillation (VF) is a major cause of sudden cardiac death in which myocardial ischemia plays a leading role. During ischaemia activation of ATP-sensitive potassium channels (K(ATP)) occurs, leading to potassium efflux from cardiomyocytes and shortening of the action potential favoring the genesis of ventricular fibrillation. In confirmation of this concept the sulfonylurea glibenclamide, which stimulates insulin release by inhibition of pancreatic K(ATP) channels, has been shown to inhibit VF in different models of ischaemia by inhibition of myocardial K(ATP) channels. HMR 1883 (1-[15-12-(5-chloro-o-anisamido)ethyl]-methoxyphenyl]sulfonyl]-3-m ethylthiourea) was designed as a cardioselective K(ATP) channel blocker. The aim of this study was to show that with this compound it is possible to separate the antifibrillatory from the insulin-releasing effect for the treatment of patients at risk of ischaemia-induced arrhythmias and sudden death. In the present study HMR 1883 reduced VF in Sprague-Dawley rats during prolonged ischaemia and also diminished mortality and the duration of VF in a separate reperfusion experiment at 3 mg/kg and 10 mg/kg with no effect on blood glucose or insulin. Glibenclamide, which was antifibrillatory at 0.3 mg/kg and 1 mg/kg, increased plasma insulin and lowered blood glucose already at a dose as low as 0.01 mg/kg. In conclusion, based on its antifibrillatory action and the absence of significant pancreatic effects at therapeutic doses, HMR 1883 is of potential clinical utility for the prevention of severe arrhythmias in patients with ischaemic heart disease. 相似文献
63.
Thomas Dierks Stefan Barta Lothar Demisch Klaus Schmeck Ekkehart Englert Andrea Kewitz Konrad Maurer Fritz Poustka 《Psychopharmacology》1999,146(1):101-107
Rationale: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of
central serotonergic activity. Objective: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels
of serotonin directly by using tryptophan depletion. Methods: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross
over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional
sources using methods published in the literature. Results: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity
dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced
tryptophan in plasma. Conclusions: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker
of central serotonergic activity.
Received: 8 March 1999 / Final version: 25 May 1999 相似文献
64.
Detection of drug-induced apoptosis by flow cytometry after alkaline extraction of ethanol fixed cells 总被引:5,自引:0,他引:5
Mihalik R Uher F Pocsik É Berczi L Benczur M Kopper L 《Pathology oncology research : POR》1996,2(1-2):78-83
A new flow cytometric method was developed to detect apoptotic cells with fragmented DNA and to determine cell cycle distribution
of viable cells, in the same sample, by propidium iodide staining. Apoptosis, in HT58 human B lymphoma cells, was induced
by etoposide and/or by staurosporine. Using appropriate alkaline solutions (between 1-10 mN NaOH in 150 mM saline) followed
by neutralization with buffer solution, the fragmented DNA can be extracted quantitatively from ethanol fixed cells. Further,
good resolution of the cell cycle distribution can be obtained in unimpaired cells without RNase treatment. Furthermore, unlike
the widely used hypotonic-detergent extraction of unfixed cells, the suggested extraction method can prevent drug-induced
disintegration of dead cells when karyorrhexis occurs.
This work was supported by Hungarian National Research Foundation (OTKA I/352 and OTKA II/2622). 相似文献
65.
Michael Stöckle Stefan Wellek Walter Meyenburg Gunther E. Voges Ulla Fischer Ulrich Gertenbach joachim W. Thüroff Christoph Huber Rudolf Hohenfellner 《Urology》1996,48(6):868-875
Objectives
To analyze the effectiveness of adjuvant polychemotherapy after radical cystectomy for nonorgan-confined transitional cell bladder cancer (Stages pT3b, pT4a, and/or pN1 or pN2).Methods
Of 166 consecutive patients undergoing cystectomy at two institutions from 1987 to 1993, 80 received adjuvant polychemotherapy with methotrexate, vinblastine, and cisplatin plus doxorubicin (MVAC) or epirubicin (MVEC), whereas 86 had cystectomy only. The patients were evaluated for relapse-free survival and length of progression-free interval on the basis of follow-up data obtained in 1995 and 1996.Results
Kaplan-Meier analysis revealed a significantly higher progression-free rate for patients after adjuvant chemotherapy (P=0.0002, log-rank test). With and without adjuvant chemotherapy, prognosis declined in a stepwise manner, depending on the extent of lymph node involvement. Nevertheless, the superior prognosis of the chemotherapy group could be demonstrated at each lymph node stage. Of the 166 patients, 49 had initially entered a prospective trial comparing adjuvant with no adjuvant treatment. That study was discontinued in December 1990 after an interim analysis revealed a significant prognostic advantage in favor of the 26 patients randomized to receive chemotherapy compared with the 23 control patients. Current follow-up data continue to demonstrate a significant improvement in progression-free survival in favor of patients randomized to receive adjuvant chemotherapy (P=0.0040). The follow-up period of patients living free of disease ranges from 58 to 96 months.Conclusions
Adjuvant chemotherapy with MVAC/MVEC leads to significant prolongation of relapse-free survival and improvement of the definitive cure rate after radical cystectomy for locally advanced transitional cell carcinoma of the urinary bladder. 相似文献66.
Elevated risk ofHelicobacter pylori infection in submarine crews 总被引:1,自引:0,他引:1
I. Hammermeister G. Janus F. Schamarowski M. Rudolf E. Jacobs M. Kist 《European journal of clinical microbiology & infectious diseases》1992,11(1):9-14
In a prospective study designed to elucidate the route of transmission ofHelicobacter pylori, the seroprevalence and incidence ofHelicobacter pylori infection was determined in the following branches of the armed forces presumed to be at increased risk of acquiring transmissible diseases by the fecal-oral or oral-oral route: German submarine crews (n=64, mean age 26.2 years) and regular officers of the French infantry (n=51, mean age 26.5 years) who had served for a minimum of three years. The submarine crews were compared with air force staff (n=74, mean age 23.7 years), and the French officers with French infantry recruits (n=135, mean age 20.5 years) who started their service at the beginning of the study. The frequency of IgG and IgA antibody responses to the 120, 88, 86 and 82 kDa proteins was determined by the immunoblot method. The frequency of a positive antibody response was strongly dependent on age (p<0.001). When results were controlled for age by the logistic regression analysis, the submarine crews revealed significantly increased frequencies of the IgG and IgA responses compared to air force staff. The antibody responses of French officers and recruits were not significantly different. It is concluded that submarine crews serving during their missions in an overcrowded space with extremely limited sanitary facilities must be considered a high-risk group forHelicobacter pylori infection. These results strongly suggest person-to-person transmission ofHelicobacter pylori, by either the oral-oral or the fecal-oral route. 相似文献
67.
Rudolf Kadatz Walter Kobinger Alexander Walland 《Naunyn-Schmiedeberg's archives of pharmacology》1976,292(2):97-103
Summary 2,2-[(4,8-bis(diethylamino)-pyrimido [5,4-d]-pyrimidine-2,6-diyl)di-(2-methoxyethyl)imino]diethanol), RA 642, combines hypertensive and vasodilating effects. In anaesthetized animals arterial blood pressure was increased by i.v. doses of 0.25–4 mg/kg in cats and 0.025–0.25 mg/kg in dogs. In conscious dogs, 25 mm increase of mean blood pressure was achieved with 0.2 mg/kg i.v. and 18.8 mg/kg p.o. Cerebral blood flow was enhanced and calculated cerebral vascular resistance was reduced by RA 642. Total peripheral resistance was diminished by 0.25–1.0 mg/kg i.v. A vasodilatation of femoral and coronary vessels was shown after intraarterial injection. This effect as well as a BaCl2-antagonism in the isolation ileum is explained by a papaverine-like relaxant effect on smooth muscle. Activity on peripheral adrenergic receptors was excluded. Hypertension was abolished in spinalized cats, indicating a central mechanism of this effect. 相似文献
68.
In this, the first of two articles discussing literature for and about children, we will be considering how writing for the young has changed, reflecting different and evolving perspectives on childhood. In the second article we will be asking whether literature can be used creatively and usefully in the training of doctors. The suggestion for the topic arose from a session we organised for paediatricians in the Communication and Management module of the MSc in Child Health at Leeds University. 相似文献
69.
70.
Combining capecitabine and gemcitabine in patients with advanced pancreatic carcinoma: a phase I/II trial. 总被引:4,自引:0,他引:4
Viviane Hess Marc Salzberg Markus Borner Rudolf Morant Arnaud D Roth Christian Ludwig Richard Herrmann 《Journal of clinical oncology》2003,21(1):66-68
PURPOSE: Preclinical studies indicate positive interactions between capecitabine, an oral fluorouracil precursor, and gemcitabine, the current standard treatment for advanced pancreatic carcinoma (APC). In this study, we investigated the addition of capecitabine to gemcitabine treatment for patients with APC. PATIENTS AND METHODS: This multicenter study included patients na?ve to chemotherapy who had histologically or cytologically confirmed, nonresectable or metastatic pancreatic carcinoma. Gemcitabine was given at a fixed dose of 1,000 mg/m(2) on days 1 and 8 of a 21-day cycle. Capecitabine was given in increasing doses orally bid for 14 days followed by a 1-week rest. The maximum-tolerated dose (MTD) was defined as one dose level below the dose causing dose-limiting toxicity (DLT) in >or= one third of a cohort of six patients. We included an additional 15 patients at the MTD. RESULTS: Thirty-six patients were included. DLT occurred at a dose of 800 mg/m(2) bid of capecitabine and consisted of myelotoxicity and mucositis. Hand-foot syndrome was not observed, and other toxic effects were mild. Thus, in this regimen, the recommended dose of capecitabine is 650 mg/m(2) bid. In 27 patients with measurable disease, we observed one complete and four partial remissions. In addition, significant drops (> 50% from baseline value) of the tumor marker CA 19-9 occurred in 14 of 24 assessable patients. CONCLUSION: The combination of capecitabine and gemcitabine is well tolerated, with apparent efficacy in patients with APC. Therefore, it is currently being compared with gemcitabine monotherapy in a phase III study. 相似文献