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101.
PURPOSE: Between September 1991 and May 1997, within the International Berlin-Frankfurt-Muenster Study Group (I-BFM-SG), a randomized study was performed aimed at assessing the efficacy of prolonged use of high-dose l-asparaginase (HD-l-ASP) during continuation therapy in children with standard risk (SR) acute lymphoblastic leukemia (ALL), treated with a reduced BFM-type chemotherapy. PATIENTS AND METHODS: The Italian, Dutch, and Hungarian groups participated in this study denominated IDH-ALL-91, and 494 children were enrolled. Treatment consisted of a BFM-type modified backbone with omission of the IB part in induction and elimination of two doses of anthracyclines during reinduction in both arms at the beginning of continuation therapy. Patients were randomly assigned to receive (YES-ASP) or not (NO-ASP) 20 weekly HD-l-ASP (25,000 IU/m2). RESULTS: The event-free-survival and overall survival probabilities at 10 years for the entire group were 82.5% (1.8) and 90.3% (1.3), respectively. Of the 490 patients eligible for random assignment, 355 (72.4%) were randomly assigned (178 YES-ASP and 177 NO-ASP). After a median follow-up of 9 years, the probability of disease-free survival at 10 years was 87.5% (SE, 2.5) for YES-ASP arm versus 78.7% (SE, 3.3) for NO-ASP arm (P = .03). In multivariate analysis, NO-ASP arm (P = .03), male sex (P = .004), and age older than 10 years (P = .0003) had a significantly adverse impact on outcome. CONCLUSION: In this subset of patients, selected with criteria not including monitoring of minimal residual disease, application of extended HD-l-ASP may improve prognosis, compensating reduced leukemia control that results from adoption of a reduced-intensity BFM-backbone for treatment of children with SR ALL.  相似文献   
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Study ObjectivesThe diagnosis of narcolepsy type 1 (NT1) is based upon the presence of cataplexy and/or a cerebrospinal fluid (CSF) hypocretin-1/orexin-A level ≤ 110 pg/mL. We determined the clinical and diagnostic characteristics of patients with intermediate hypocretin-1 levels (111–200 pg/mL) and the diagnostic value of cataplexy characteristics in individuals with central disorders of hypersomnolence.MethodsRetrospective cross-sectional study of 355 people with known CSF hypocretin-1 levels who visited specialized Sleep-Wake Centers in the Netherlands. For n = 271, we had full data on cataplexy type (“typical” or “atypical” cataplexy).ResultsCompared to those with normal hypocretin-1 levels (>200 pg/mL), a higher percentage of individuals with intermediate hypocretin-1 levels had typical cataplexy (75% or 12/16 vs 9% or 8/88, p < .05), and/or met the diagnostic polysomnographic (PSG) and Multiple Sleep Latency Test (MSLT) criteria for narcolepsy (50 vs 6%, p < .001). Of those with typical cataplexy, 88% had low, 7% intermediate, and 5% normal hypocretin-1 levels (p < .001). Atypical cataplexy was also associated with hypocretin deficiency but to a lesser extent. A hypocretin-1 cutoff of 150 pg/mL best predicted the presence of typical cataplexy and/or positive PSG and MSLT findings.ConclusionIndividuals with intermediate hypocretin-1 levels or typical cataplexy more often have outcomes fitting the PSG and MSLT criteria for narcolepsy than those with normal levels or atypical cataplexy. In addition, typical cataplexy has a much stronger association with hypocretin-1 deficiency than atypical cataplexy. We suggest increasing the NT1 diagnostic hypocretin-1 cutoff and adding the presence of clearly defined typical cataplexy to the diagnostic criteria of NT1. Clinical trial information: This study is not registered in a clinical trial register, as it has a retrospective database design.  相似文献   
104.
105.

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   
106.
107.
Pricing and reimbursement of pharmaceuticals are of concern for pharmacists. Different countries have different ways of organising their health care systems. The place for pharmaceuticals within these systems also differ. This article looks into the price and reimbursement systems for medicinal products in Germany, Sweden, the UK and Norway. Various ways of organising the pharmaceutical market emerge. Some existing measures have been in place for a long time while others have been introduced more recently. A common goal for the four countries seems to be the drive to cut costs, and attempts to do this can be directed through various reimbursement systems, by focusing on prices or by influencing the physicians' prescribing behaviour, either through the use of advice or through the use of budgets. It is important for the pharmacists to have indepth knowledge of the price and reimbursement system they have to work within in order to be of full service to their customers.  相似文献   
108.
The dried flowers from Aloe vera (L.) Burm. f. (Aloe barbadensis Mill.) (Asphodelaceae) were analysed by means of HPLC-DAD and HPLC-MS/MS, verifying chlorogenic, caffeic, 5-P-coumaroylquinic, caffeoylshikimic, 5-feruloylquinic, 5-P-CIS-coumaroylquinic, P-coumaric and ferulic acid as well as luteolin, apigenin, quercetin, kaempferol, isoorientin, isovitexin and their 7-O-glucosides, saponarin and lutonarin. On searching for anthranoids in the flower extract, aloe-emodin as well as the glycosylchromone aloeresin B could be identified. Aloin A and B, the laxative principle of the drug Cura?ao-Aloes, are not accumulated in the dried flowers. The polyphenol content of three different batches was 0.73 - 1.01% (+/- 0.05%) and the flavonoid content 0.24 - 0.34% (+/- 0.01%). The hydrophilic antioxidative capacity amounted to 85.7 - 94.9 (+/- 0.5) micromol TEAC/g dried Aloe vera flower and was directly correlated with the polyphenol and flavonoid contents.  相似文献   
109.
 Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the development of rat offspring were studied after administration of a loading dose of 300 or 1000 ng TCDD/kg body wt on day 19 of pregnancy, followed by weekly maintenance doses of 120 or 400 ng TCDD/kg body wt. The dose regimens led to a fluctuation of average TCDD concentrations in the liver of the offspring of 4.9–14.9 ng/g (TCDD1000/400 group) or 1.4–6.3 ng/g (TCDD300/120 group) during the course of the experiment. In both TCDD-exposed groups the body weight of the offspring was significantly lower on postnatal day 7 (PND 7); in the high dose group from PND 7 to PND 31. Some landmarks of postnatal development were retarded in the exposed groups; in particular, the vaginal opening was delayed for several days in both TCDD-exposed groups. The TCDD-exposed animals revealed a reduced ability to remain on a rotating rod. During reflex testing, the rate of successfully responding animals was higher in the exposed groups. No statistically significant differences in the locomotor activity between controls and TCDD-exposed offspring were detectable under our experimental conditions. In a discrimination learning test no effects on the learning ability were found. However, TCDD-exposed offspring showed an increase in unanswered trials during critical phases of the task. They also exhibited increased locomotor activity in a novel environment; prior to an amphetamine challenge dose of 1 mg/kg body weight. Amphetamine-induced activity was decreased in a dose-dependent manner. Received: 2 May 1994 / Accepted: 13 July 1994  相似文献   
110.
With the recent development of reliable portable pumps and safe venous access systems, continuous infusion of chemotherapeutic agents on an out-patient basis has become feasible. Advantages of continuous infusion are the long-term exposure of tumour cells to the drug and the fact that most toxic effects are reduced for doxorubicin, epirubicin and mitoxantrone due to elimination of the high peak plasma levels. Preliminary data for doxorubicin suggest that its antitumour activity is maintained. Pharmacokinetic studies with epirubicin and mitoxantrone showed a linear relationship between drug dose infused and the steady-state plasma level for these drugs. The area under the curve for leukocytes drug level was higher during continuous infusion than after an equitoxic bolus injection of epirubicin and mitoxantrone. Well-randomized clinical trials will be necessary to investigate the role of continuous infusion of antracyclines and mitoxantrone in cancer chemotherapy in the future.  相似文献   
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