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51.
A 38 year old female office worker was admitted with a newly discovered blood pressure of 250/110 mm Hg. Evaluation for secondary forms of hypertension was negative and treatment was begun. Sodium excretion was markedly reduced, plasma aldosterone was normal, and plasma renin activity was low. Therefore, presence of an aldosterone-like activity was suspected. Eventually, the patient confessed to abusing "Turkish Pepper", a brand of Scandinavian liquorice candies and "Fisherman's Friend", another brand of liquorice candies, concurrently. After eliminating liquorice from her diet, the hypertension disappeared thus allowing her antihypertensive treatment to be stopped. 相似文献
52.
Colleen J. Gilbert William P. Petros James Vredenburgh Atif Hussein Maureen Ross Peter Rubin Randy Fehdrau Colleen Cavanaugh Donald Berry Craig McKinstry William P. Peters 《Cancer chemotherapy and pharmacology》1998,42(6):497-503
Purpose: Both ondansetron and cyclophosphamide are thought to be metabolized by hepatic microsomal processes. The purpose of this
study was to evaluate the potential pharmacokinetic interactions between ondansetron and high-dose alkylating agent chemotherapy.
Methods: A total of 54 breast cancer patients receiving high-dose cyclophosphamide, cisplatin and carmustine were treated prospectively
in four sequential cohorts. Cohorts I and II received continuous infusions of both ondansetron and prochlorperazine, and cohorts
III and IV received a continuous infusion of ondansetron alone at the same doses. All patients received lorazepam every 4 h.
A group of 75 matched historical controls had received a continuous infusion of prochlorperazine with lorazepam. Pharmacokinetic
monitoring of each drug used in the high-dose chemotherapy regimen was conducted. Results: Median AUCs of cyclophosphamide in patients receiving ondansetron (73.6 mg/ml · min) were lower than those of the control
patients (88.3 mg/ml · min, n = 75, P = 0.0004), but the median cisplatin AUC was approximately 10% higher and no difference in the disposition of carmustine was
demonstrated. Patients treated with ondansetron displayed a higher frequency of headaches than the controls. The frequency
of achieving complete emetic control was greater in the ondansetron + prochlorperazine groups compared to the ondansetron
alone groups and was greater in both these groups than in the prochlorperazine alone group on the first day of therapy only.
Conclusion: Ondansetron altered the systemic exposure to cyclophosphamide when these agents were administered concomitantly. Ondansetron
did not substantially improve overall emetic control when used alone but may improve control in combination with prochlorperazine.
Future randomized studies are needed to delineate the effect of ondansetron on the disposition of the active cyclophosphamide
metabolites so that clinical implications can be addressed.
Received: 28 October 1997 / Accepted: 9 March 1998 相似文献
53.
Frequency of pancreatitis after endoscopic retrograde cholangiopancreatography with iopromid or iotrolan: a randomized trial 总被引:1,自引:0,他引:1
Blood isotone contrast media is considered to be less toxic to vascular and pancreatic duct endothelium than high-osmolar
contrast media. In this study we assessed the impact of a low-osmolar contrast agent compared with a blood isotone product
on pancreatic damage induced by endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic retrograde sphincterotomy
(EST). In a prospective trial 42 consecutive ERCP/EST patients were randomized to receive either iopromid, a low-osmolar non-ionic
contrast agent (770 mosmol/kg H2O), or iotrolan, a blood-isotone non-ionic product (320 mosmol/kg H2O). The endoscopies were performed by two experienced endoscopists. Forty patients were included in the study. Blood samples
were collected before and 40 min, 2, 4, 6 and 24 h after the endoscopic procedure. Samples were analysed for pancreatic serum
enzymes, acute-phase proteins and blood counts. A clinical pain score was investigated. Post-ERCP pancreatitis was diagnosed
in 2 patients in the iopromid group and in 5 patients in the iotrolan group. There was no significant difference between groups
in the time course of pancreatic serum enzymes, acute-phase proteins or in the pain score. Due to the small number of patients
in this study, only stronger differences caused by the two contrast media could have led to statistically significant results.
We did not observe statistically significant differences in comparing iotrolan and iopromid concerning ERCP/EST-induced pancreatic
damage.
Received: 26 February 1999; Revised: 14 May 1999; Accepted: 9 June 1999 相似文献
54.
Paul J Gresch Randy L Smith Robert J Barrett Elaine Sanders-Bush 《Neuropsychopharmacology》2005,30(9):1693-1702
Tolerance is defined as a decrease in responsiveness to a drug after repeated administration. Tolerance to the behavioral effects of hallucinogens occurs in humans and animals. In this study, we used drug discrimination to establish a behavioral model of lysergic acid diethylamide (LSD) tolerance and examined whether tolerance to the stimulus properties of LSD is related to altered serotonin receptor signaling. Rats were trained to discriminate 60 microg/kg LSD from saline in a two-lever drug discrimination paradigm. Two groups of animals were assigned to either chronic saline treatment or chronic LSD treatment. For chronic treatment, rats from each group were injected once per day with either 130 microg/kg LSD or saline for 5 days. Rats were tested for their ability to discriminate either saline or 60 microg/kg LSD, 24 h after the last chronic injection. Rats receiving chronic LSD showed a 44% reduction in LSD lever selection, while rats receiving chronic vehicle showed no change in percent choice on the LSD lever. In another group of rats receiving the identical chronic LSD treatment, LSD-stimulated [35S]GTPgammaS binding, an index of G-protein coupling, was measured in the rat brain by autoradiography. After chronic LSD, a significant reduction in LSD-stimulated [35S]GTPgammaS binding was observed in the medial prefrontal cortex and anterior cingulate cortex. Furthermore, chronic LSD produced a significant reduction in 2,5-dimethoxy-4-iodoamphetamine-stimulated [35S]GTPgammaS binding in medial prefrontal cortex and anterior cingulate cortex, which was blocked by MDL 100907, a selective 5-HT2A receptor antagonist, but not SB206553, a 5-HT2C receptor antagonist, indicating a reduction in 5-HT2A receptor signaling. 125I-LSD binding to 5-HT2A receptors was reduced in cortical regions, demonstrating a reduction in 5-HT2A receptor density. Taken together, these results indicate that adaptive changes in LSD-stimulated serotonin receptor signaling may mediate tolerance to the discriminative stimulus effects of LSD. 相似文献
55.
Donna L Forrest Donna E Hogge Thomas J Nevill Stephen H Nantel Michael J Barnett John D Shepherd Heather J Sutherland Cynthia L Toze Clayton A Smith Julye C Lavoie Kevin W Song Nicholas J Voss Randy D Gascoyne Joseph M Connors 《Journal of clinical oncology》2005,23(31):7994-8002
PURPOSE: To determine the incidence of second malignancies among patients with Hodgkin's lymphoma (HL) treated with autologous hematopoietic stem cell transplantation (AHSCT) compared with patients receiving conventional therapy alone and to identify potential risk factors for their occurrence. PATIENTS AND METHODS: We analyzed data on 1,732 consecutive patients with HL treated at the British Columbia Cancer Agency from 1976 to 2001, including 202 patients undergoing AHSCT. The median follow-up duration was 9.8 years for the whole cohort, 9.7 years for those patients treated with conventional therapy, and 7.8 years from AHSCT. RESULTS: The cumulative incidence of developing any second malignancy 15 years after therapy for HL was 9% (risk ratio = 3.5; P < .001); however, the incidence did not differ between those patients receiving conventional therapy alone compared with those undergoing AHSCT (10% and 8%, respectively; P = .48). In multivariate analysis, the only factor significantly associated with an increased risk of developing any second neoplasm or solid tumor was age > or = 35 years (P < .0001). An increased risk of therapy-induced acute myeloid leukemia and therapy-induced myelodysplastic syndrome was seen for patients aged > or = 35 years (P = .03) and stage III/IV (P = .04). CONCLUSION: Patients with HL are at increased risk of developing a second neoplasm. However, those patients undergoing AHSCT do not seem to be at greater risk compared with those patients receiving conventional therapy alone, at least during the first decade after therapy. 相似文献
56.
57.
Berthold Pemp Randy H. Kardon Karl Kircher Elisabeth Pernicka Ursula Schmidt-Erfurth Andreas Reitner 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2013,251(7):1841-1848
Background
Automated detection of subtle changes in peripapillary retinal nerve fibre layer thickness (RNFLT) over time using optical coherence tomography (OCT) is limited by inherent image quality before layer segmentation, stabilization of the scan on the peripapillary retina and its precise placement on repeated scans. The present study evaluates image quality and reproducibility of spectral domain (SD)-OCT comparing different rates of automatic real-time tracking (ART).Methods
Peripapillary RNFLT was measured in 40 healthy eyes on six different days using SD-OCT with an eye-tracking system. Image brightness of OCT with unaveraged single frame B-scans was compared to images using ART of 16 B-scans and 100 averaged frames. Short-term and day-to-day reproducibility was evaluated by calculation of intraindividual coefficients of variation (CV) and intraclass correlation coefficients (ICC) for single measurements as well as for seven repeated measurements per study day.Results
Image brightness, short-term reproducibility, and day-to-day reproducibility were significantly improved using ART of 100 frames compared to one and 16 frames. Short-term CV was reduced from 0.94?±?0.31 % and 0.91?±?0.54 % in scans of one and 16 frames to 0.56?±?0.42 % in scans of 100 averaged frames (P?≤?0.003 each). Day-to-day CV was reduced from 0.98?±?0.86 % and 0.78?±?0.56 % to 0.53?±?0.43 % (P?≤?0.022 each). The range of ICC was 0.94 to 0.99. Sample size calculations for detecting changes of RNFLT over time in the range of 2 to 5 μm were performed based on intraindividual variability.Conclusion
Image quality and reproducibility of mean peripapillary RNFLT measurements using SD-OCT is improved by averaging OCT images with eye-tracking compared to unaveraged single frame images. Further improvement is achieved by increasing the amount of frames per measurement, and by averaging values of repeated measurements per session. These strategies may allow a more accurate evaluation of RNFLT reduction in clinical trials observing optic nerve degeneration. 相似文献58.
Lahm v. Braunbehrens Schläpfer Haagen Goebel 《Journal of cancer research and clinical oncology》1942,53(3-4):261-264
Ohne Zusammenfassung 相似文献
59.
60.
Edelman RR Salanitri G Brand R Dunkle E Ragin A Li W Mehta U Berlin J Newmark G Gore R Patel B Carillo A Vu A 《Investigative radiology》2006,41(2):175-180
OBJECTIVES: We sought to perform a preliminary comparison of signal-to-noise ratio (SNR) and image quality for magnetic resonance imaging (MRI) of the pancreas at 1.5 and 3 T. MATERIALS AND METHODS: Two imaging cohorts were studied using a T2-weighted, single-shot fast spin-echo pulse sequence and a T1-weighted, fat-suppressed 3D gradient-echo pulse sequence. In the first cohort, 4 subjects were imaged using identical imaging parameters before and after contrast administration at 1.5 and 3.0 T. The SNR was quantified for the pancreas as well as for the liver, spleen, and muscle. In a second cohort of 12 subjects in whom the receiver bandwidth was adjusted for field strength, SNR measurements and qualitative rankings of image quality were performed. RESULTS: In the study cohort using identical imaging parameters at both magnetic field strengths, the mean (SD) ratios of SNR at 3.0 to 1.5 T of the single-shot fast spin-echo images for the pancreas, liver, spleen, and muscle were 1.63 (0.39), 1.82 (0.39), 1.45 (0.18), 2.01 (0.16), respectively. For the precontrast fat-suppressed 3D gradient-echo sequence, the corresponding ratios were 1.28 (0.29), 1.26 (0.30), 1.16 (0.27), and 1.76 (0.45), respectively; for the arterial phase, the corresponding ratios were 2.02 (0.28), 1.60 (0.42), 1.47 (0.26), and 1.94 (0.32), respectively; and for the delayed postcontrast phase, the corresponding ratios were 1.63 (0.51), 2.01 (0.25), 1.66 (0.06), and 2.31 (0.47), respectively. The SNR benefit of 3.0 T was significantly greater on contrast-enhanced as compared with noncontrast T1-weighted 3D gradient-echo images. In the second study cohort, SNR was superior at 3.0 T, although the use of a reduced readout bandwidth at 1.5 T substantially diminished the advantage of the higher field system. With qualitative comparison of images obtained at the 2 magnetic field strengths, the fat-suppressed 3D gradient-echo images obtained at 3.0 T were preferred, whereas the single shot fast spin-echo images obtained at 1.5 T were preferred because of better signal homogeneity. CONCLUSIONS: Our results in a small cohort of volunteers and patients demonstrate a marked improvement in SNR at 3.0 T compared with 1.5 T (by a factor of 2 in some cases) when identical imaging parameters were used. The SNR advantage at 3.0 T is diminished but persists when the receiver bandwidth is adjusted for magnetic field strength. The results suggest that 3.0 T may offer promise for improved body MRI, although further technical development to optimize SNR and improve signal homogeneity will be needed before its full potential can be achieved. 相似文献