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991.
992.
Spaander MC Darwish Murad S van Buuren HR Hansen BE Kuipers EJ Janssen HL 《Gastrointestinal endoscopy》2008,67(6):821-827
BACKGROUND: Esophagogastric variceal bleeding is the most important complication of extrahepatic portal vein thrombosis (EPVT) and is usually treated endoscopically. Little is known about the prognosis of these patients. OBJECTIVES: To investigate the long-term clinical outcome and efficacy of endoscopic treatment in patients with esophagogastric variceal bleeding secondary to EPVT. DESIGN: Retrospective observational study. SETTINGS: Single university center. PATIENTS: Twenty-seven consecutive patients with esophagogastric variceal bleeding, secondary to noncirrhotic, nonmalignant EPVT, who underwent endoscopic treatment between 1982 and 2005. INTERVENTIONS: Endoscopic band ligation and/or endoscopic sclerotherapy. MAIN OUTCOME MEASUREMENTS: The overall rebleeding risk, overall survival, complications of the endoscopic procedures, and predictive values of rebleeding. Analyses were performed by the Kaplan-Meier method and univariate Cox regression. RESULTS: All patients were followed-up after the first endoscopically treated variceal bleeding. A total of 241 endoscopic procedures were performed. In all patients, initial control of bleeding was obtained. The overall rebleeding risk was 23% (95% CI, 0%-24%) at 1 year and 37% (95% CI, 43%-83%) at 5 years. Extension of thrombosis into the splenic vein and the presence of fundal varices were significant predictors of rebleeding, with a nearly 5-fold increased risk for patients with EPVT and fundal varices at the time of the first variceal hemorrhage (hazard ratio 5.07, P = .01). A portosystemic shunt procedure was performed in 5 patients: 4 for variceal bleeding and in one patient for refractory ascites. Seven patients died, none from variceal bleeding. Overall 5-year and 10-year survivals were 100% and 62% (95% CI, 38%-96%), respectively. LIMITATIONS: Retrospective design. CONCLUSIONS: In patients with variceal bleeding secondary to EPVT endoscopic treatment, in particular, band ligation appears safe and effective. EPVT-related mortality is primarily determined by other causes than variceal bleeding. 相似文献
993.
Brugts MP van den Beld AW Hofland LJ van der Wansem K van Koetsveld PM Frystyk J Lamberts SW Janssen JA 《The Journal of clinical endocrinology and metabolism》2008,93(7):2515-2522
CONTEXT: Low IGF-I signaling activity prolongs lifespan in certain animal models, but the precise role of IGF-I in human survival remains controversial. The IGF-I kinase receptor activation assay is a novel method for measuring IGF-I bioactivity in human serum. We speculated that determination of circulating IGF-I bioactivity is more informative than levels of immunoreactive IGF-I. OBJECTIVE: Our objective was to study IGF-I bioactivity in relation to human survival. DESIGN, SETTING, AND STUDY PARTICIPANTS: We conducted a prospective observational study at a clinical research center at a university hospital of 376 healthy elderly men (aged 73-94 yr). MAIN OUTCOME MEASURES: IGF-I bioactivity was determined by the IGF-I kinase receptor activation assay. Total and free IGF-I were determined by IGF-I immunoassays. Mortality was registered during follow-up (mean 82 months). RESULTS: During the follow-up period of 8.6 yr, 170 men (45%) died. Survival of subjects in the highest quartile of IGF-I bioactivity was significantly better than in the lowest quartile, both in the total study group [hazard ratio (HR) = 1.8; 95% confidence interval (95% CI) = 1.2-2.8; P = 0.01] as well as in subgroups having a medical history of cardiovascular disease (HR = 2.4; 95% CI = 1.3-4.3; P = 0.003) or a high inflammatory risk profile (HR = 2.3; 95% CI = 1.2-4.5; P = 0.01). Significant relationships were not observed for total or free IGF-I. CONCLUSION: Our study suggests that a relatively high circulating IGF-I bioactivity in elderly men is associated with extended survival and with reduced cardiovascular risk. 相似文献
994.
995.
Bupropion is widely used in the treatment of depression. There are, however, limited data on its long-term effects on monoaminergic neurons and therefore the mechanism of its delayed onset of action is at present not well understood. The present study was conducted to examine the effects of prolonged bupropion administration on the firing activity of dorsal raphe nucleus (DRN), locus coeruleus (LC), and ventral tegmental area (VTA) neurons. Spontaneously firing neurons were recorded extracellularly in rats anesthetized with chloral hydrate. Bupropion (30 mg/kg/day) was administered using subcutaneously implanted minipumps. In the DRN, the firing rate of serotonin (5-HT) neurons was significantly increased after 2, 7 and 14 days of administration. The suppressant effect of LSD was significantly diminished after the two-day regimen, indicating a desensitization of 5-HT1A autoreceptors. In the LC, the firing rate of norepinephrine (NE) neurons was significantly attenuated after a 2-day regimen, but recovered progressively over 14 days of administration. The suppressant effect of clonidine on NE neuronal firing was significantly attenuated in rats treated with bupropion for 14 days, indicating a desensitization of α2-adrenoceptors. In the VTA, neither 2 nor 14 days of bupropion administration altered the firing and burst activity of dopamine neurons. These results indicate that bupropion, unlike 5-HT reuptake inhibitors, promptly increased 5-HT neuronal activity, due to early desensitization of the 5-HT1A autoreceptor. The gradual recovery of neuronal firing of NE neurons, due to the desensitization of α2-adrenoceptors, in the presence of the sustained increase in 5-HT neuronal firing, may explain in part the delayed onset of action of bupropion in major depression. 相似文献
996.
Dissolution Media Simulating Conditions in the Proximal Human Gastrointestinal Tract: An Update 总被引:5,自引:3,他引:2
PURPOSE: The aim of this study was to update the compositions of biorelevant media to represent the composition and physical chemical characteristics of the gastrointestinal fluids as closely as possible while providing physical stability during dissolution runs and short-term storage. METHODS: Media were designed to reflect postprandial conditions in the stomach and proximal small intestine in the "early", "middle", and "late" phases of digestion. From these "snapshot" media, general media for simulating postprandial conditions were devised. Additionally, media reflecting preprandial conditions in the stomach and small intestine were revisited. RESULTS: A set of four media is presented. A recently published medium to represent the fasted stomach, FaSSGF, needed no further revision. To simulate the postprandial stomach, a new medium, FeSSGF, is presented. Media representing the upper small intestine in the fed and fasted states were fine-tuned according to physicochemical and biochemical characteristics in vivo. All four media proved to be stable under ambient storage conditions for at least 72 h as well as under usual dissolution test conditions. CONCLUSIONS: The updated dissolution media can be used to predict formulation performance and food effects in vivo. These media are more physiologically relevant and show better physical stability than their corresponding predecessors. 相似文献
997.
Schiffmann S Maier TJ Wobst I Janssen A Corban-Wilhelm H Angioni C Geisslinger G Grösch S 《Biochemical pharmacology》2008,76(2):179-187
Celecoxib, a COX-2 (cyclooxygenase-2)-selective inhibitor (coxib), is the only NSAID (non-steroidal anti-inflammatory drug) that has been approved for adjuvant treatment of patients with familial adenomatous polyposis. To investigate if the anti-proliferative effect of celecoxib extends to other coxibs, we compared the anti-proliferative potency of all coxibs currently available (celecoxib, rofecoxib, etoricoxib, valdecoxib, lumiracoxib). Additionally, we used methylcelecoxib (DMC), a close structural analogue of celecoxib lacking COX-2-inhibitory activity. Due to the fact that COX-2 inhibition is the main characteristic of these substances (with exception of methylcelecoxib), we conducted all experiments in COX-2-overexpressing (HCA-7) and COX-2-negative (HCT-116) human colon cancer cells, in order to elucidate whether the observed effects after coxib treatment depend on COX-2 inhibition. Cell survival was assessed using the WST proliferation assay. Apoptosis and cell cycle arrest were determined using flow cytometric and Western blot analysis. The in vitro results were confirmed in vivo using the nude mouse model. Among all coxibs tested, only celecoxib and methylcelecoxib decreased cell survival by induction of cell cycle arrest and apoptosis and reduced the growth of tumor xenografts in nude mice. None of the other coxibs (rofecoxib, etoricoxib, valdecoxib, lumiracoxib) produced anti-proliferative effects, indicating the lack of a class effect and of a role for COX-2. Our data emphasize again the outstanding anti-proliferative activity of celecoxib and its close structural analogue methylcelecoxib in colon carcinoma models in vitro and in vivo. 相似文献
998.
999.
1000.
Svenja Janssen Maurizio A. Trippolini Roger Hilfiker Peter Oesch 《Journal of occupational rehabilitation》2016,26(3):253-263
Purpose To develop a modified version of the spinal function sort (M-SFS) by measuring work-related self-efficacy beliefs in patients with chronic low back pain. Methods A mixed method design consisting of three different methods (M1–3) was performed. In semi-structured interviews participants were asked how often they performed the activities of the 50 SFS items in 1 week, and which spinal postures and movements were associated with their back pain (M1). Quantitative analysis of previously obtained SFS data investigated internal consistency, unidimensionality, item response, and floor and ceiling effect (M2). Experts rated the SFS items based on their relevance (M3). The findings from these methods were used within a final scoring system for item reduction. Results From semi-structured interviews with 17 participants, eight new items emerged (M1). Quantitative analysis of 565 data sets (M2) revealed very high internal consistency of all items (Cronbach’s alpha = 0.98) indicating item redundancy; unidimensionality of the SFS was supported by principal component analysis; good item response was confirmed by Rasch analysis; and a floor effect of four items depicting very heavy material handling was found. Experts agreed on 8 out of the 50 SFS as relevant (M3). From the original SFS, 12 items met the predefined summary score of 9. Conclusions A modified version of the SFS with 20 items has been developed. Feasibility, reliability and validity of this modified version must be tested before it can be used in clinical practice. 相似文献