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Kerstin Schmidt Johannes Hoffend Annette Altmann Ludwig G Strauss Antonia Dimitrakopoulou-Strauss Britta Engelhardt Dirk Koczan J?rg Peter Thomas J Dengler Walter Mier Michael Eisenhut Uwe Haberkorn Ralf Kinscherf 《Journal of nuclear medicine》2006,47(3):543-551
Growth of malignant tumors is dependent on sufficient blood supply. Thus, inhibition of tumor angiogenesis is emerging as a promising target in the treatment of malignancies. Human angiostatin (hANG) is one of the most potent inhibitors of endothelial cell proliferation, angiogenesis, and tumor growth in vivo. However, its mechanisms operating in vivo are not well understood. METHODS: To obtain more information about functional changes in the angiogenic process, we established Morris hepatoma (MH3924A) cell lines expressing hANG (hANG-MH3924A). The effects of hANG expression on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) were measured in coculture experiments in vitro. To evaluate changes in tumor perfusion and blood volume, H2 15O and 68Ga-DOTA-albumin (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N',N'-tetraacetic acid) were used for PET studies in vivo. Additionally, immunohistologic quantification of vascularization, apoptosis, and proliferation as well as gene array analyses were performed. RESULTS: Our in vitro experiments demonstrate reduced proliferation and increased apoptosis in HUVECs when being cocultured with hANG-MH3924A. In support, tumor growth of hANG-MH3924A is diminished by 95% in vivo. However, tumor perfusion and blood volume are increased in hANG-MH3924A corresponding to an increased microvessel density. Furthermore, hANG-transfected tumors show changes in expression of genes related to apoptosis, stress, signal transduction, and metabolism. CONCLUSION: hANG expression leads to inhibition of tumor growth, increased apoptosis, and changes in the expression of multiple genes involved in stress reactions, signal transduction, and apoptosis, which indicates a multifactorial reaction of tumors. An enhanced microvessel density is seen as part of these reactions and is associated with increased perfusion as measured by PET. 相似文献
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I. Kaare Tesdal Werner Jaschke Mathias Bühler Ralf Adamus Thomas Filser Eggert Holm Max Georgi 《Cardiovascular and interventional radiology》1997,20(1):29-37
Purpose To evaluate prospectively our experience with transjugular intrahepatic portosystemic shunt (TIPS) using four different metallic
stents.
Methods Between November 1991 and April 1995, 57 patients (41 men and 16 women; age 35–72 years, mean 54 years) underwent the TIPS
procedure. Techniques for portal vein localization before and during TIPS were fluoroscopy, computed tomography (CT) studies,
wedged hepatic venography, arterial portography, and ultrasound. After predilation we deployed balloon-expandable (n=48) and self-expanding (n=45) metallic stents. Fifteen patients underwent variceal embolization. Initial follow-up angiograms (mean 6.9 months, range
3–24 months) were obtained in 39 of these patients.
Results Fifty-three patients (93%) had successful TIPS placement. The mean decrease in portal pressure was 42.7%. Besides fluoroscopy,
the most helpful techniques for portal vein localization were venography and CT. Residual stenosis (n=1) and late shortening (n=4) of Wallstents resulted in shunt dysfunction. The technical problems encountered with the Palmaz stent resulted from its
lack of flexibility. We combined balloon-expandable and self-expanding stents in 12 patients. The 30-day and late follow-up
(mean 11.9 months) percutaneous reintervention rates were 11.3% and 64.2%, respectively. There were no clinically significant
complications related to the TIPS insertions.
Conclusion An ideal stent does not exist for TIPS, and the authors recommend combining a Palmaz stent with a flexible self-expanding
stent. 相似文献
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Ralf F Schuler Frank A Roberts 《Practical procedures & aesthetic dentistry》2005,17(10):697-704; quiz 706
While less emphasis has traditionally been placed on aesthetics in order to focus on successful osseointegration, increased success rates provided by contemporary endosseous root-form dental implants have improved postoperative peri-implant hard and soft tissue structures. The criteria for the evaluation of implant success should, therefore, include lack of pain, mobility, radiolucency, bone loss, infection, or paresthesia, as well as acceptability and stable aesthetics. This article discusses surgical means to preserve or restore hard and soft tissues around dental implants to achieve ideal and predictable outcomes. 相似文献
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Bernhard Croissant Fred Rist Ralf Demmel Robert Olbrich 《International journal of psychophysiology》2006,61(2):253-261
Individuals with a family history of alcoholism (FH+) are at risk to develop alcohol problems. In several studies, psychophysiological stress responses were more attenuated by alcohol in FH+ than in FH- subjects. However, it is not clear from these studies, if this stronger stress-response dampening effect of alcohol (SRD) in FH+ subjects is confined to aversive stimuli, or would hold for nonaversive stress conditions as well. Also, male and female FH+ subjects seem to respond differently to the alcohol challenge, but have rarely been directly compared in a SRD paradigm. Participants were 54 female and 63 male healthy adults; 31 women were daughters (DOAs) and 40 men were sons (SOAs) of alcohol-dependent fathers. The remaining 23 women (DONAs) and 23 men (SONAs) had no FH of any alcohol use disorder. The participants took part in two laboratory sessions, one with and one without alcohol. In each session, three stressor procedures were presented. Heart rate is the main dependent variable in this report. SOAs, but not SONAs showed a tendency towards SRD. Among female participants, a strong SRD occurred, but contrary to our expectation only in controls. Stress responses and SRD effects were somewhat stronger in the aversive than in the rewarding task. The extent of alcohol induced SRD was strongly influenced by BAL and the amplitude of the stress response in the no-alcohol condition (multiple regression analysis). Thus, aversive tasks might have the advantage of eliciting stronger stress responses than rewarding tasks, thereby providing better conditions for observing differences in alcohol induced SRD between FH+ and FH- subjects. 相似文献
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Claudia Trenkwalder MD Heike Benes MD Ludger Grote MD Svenja Happe MD Birgit Högl MD Johannes Mathis MD Gerda M. Saletu‐Zyhlarz MD Ralf Kohnen PhD CALDIR study group 《Movement disorders》2007,22(5):696-703
We report the first large-scale double-blind, randomly assigned study to compare two active dopaminergic therapies for Restless Legs Syndrome (RLS), the dopamine agonist cabergoline (CAB) and levodopa/benserazide (levodopa). Patients with idiopathic RLS were treated with fixed daily doses of 2 or 3 mg CAB or 200 or 300 mg levodopa for 30 weeks. Efficacy was assessed by changes in the IRLS (International RLS Severity Scale) and by time to discontinuation of treatment due to loss of efficacy or augmentation. 361 of 418 screened patients (age 58 +/- 12 years, 71% females) were randomly assigned and treated (CAB: n = 178; levodopa: n = 183) in 51 centers of four European countries. Baseline IRLS total score was 25.7 +/- 6.8. The baseline-adjusted mean change from baseline to week 6 in IRLS sum score was d = -16.1 in the CAB group and d = -9.5 in the levodopa group (d = -6.6, P < 0.0001). More patients in the levodopa group (24.0%) than in the CAB group (11.9%, P = 0.0029, log-rank test) discontinued because of loss of efficacy (14.2% vs. 7.9%, P = 0.0290) or augmentation (9.8% vs. 4.0%, P = 0.0412). Adverse events (AEs) occurred in 83.1% of the CAB group and in 77.6% of the levodopa group. In both groups, most frequent AEs were gastrointestinal symptoms (CAB: 55.6%, levodopa: 30.6%, P < 0.0001). This first large-scale active controlled study in RLS showed superior efficacy of cabergoline versus levodopa after a 30-week long-term therapy. Tolerability was found more favorable with levodopa than with cabergoline. 相似文献
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Trauma und Berufskrankheit - Zusammenfassung Diese Arbeit beschäftigt sich mit der Häufigkeit, dem Entstehungsmechanismus und der Behandlung von Bizepssehnenrupturen. Veränderte... 相似文献
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