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31.
The aim of this Phase III, balanced randomised trial was to compare continuous intravenous infusion (CVI) of 5-FU with bolus (B) administration for metastatic colorectal cancer (CRC). One hundred and fifty-five non-pretreated patients were randomised to receive CVI 5-FU at a dose of 750 mg/m2/day (d), 7 d every 21 d (n = 77), or bolus 5-FU 500 mg/m2/d x 5 d every 28 d (n = 78). Incremental dose escalation at 50 mg per step was recommended in the absence of toxicity. All the patients had measurable metastatic disease (M), particularly, liver and a good performance status (WHO grade 0-1). Dose intensity was significantly higher in CVI than in the bolus group: 1369 mg/m2/week versus 558 mg/m2/week (P = 0.0001). Grade II-IV stomatitis was more frequent in the CVI group (31% versus 9%; P < 0.0001) as was hand and foot syndrome (14% versus 3%; P < 0.001). Diarrhoea (22% versus 12%) and grade III granulocytopenia (2% versus 6%) were comparable. Responses were more frequent in the CVI (26%) than in the bolus group (13%) (P < 0.04); progression-free survival was higher for the CVI group (P = 0.04), but there was no statistical difference in overall survival (median: 10 months (m) compared to 9 m), and 1 year survival (SD) 42% (6%) versus 40% (6%). In the multivariate analysis, survival was better for patients with a good PS, well-differentiated adenocarcinomas and a primary tumour without serosal extension. In conclusion, with a higher dose intensity, CVI 5-FU improved tumour control, but not overall survival.  相似文献   
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33.
N-(phosphonacetyl)-disodium L-aspartic acid (PALA) demonstrates a synergistic antitumor effect when combined with 5-Fluorouracil (5-FU) in in vitro studies. In a Phase II trial, 23 eligible patients with unresectable or metastatic adenocarcinoma of the stomach were treated with weekly i.v. bolus PALA (250 mg/M2) followed 24 hours later by a 24-hour infusion of 5-FU (2600 mg/M2) for an initial period of 8 weeks. No objective responses were noted. PALA and 5-FU is inactive against gastric adenocarcinoma at the doses and schedule used in this trial.  相似文献   
34.
1. Interaction between topical isoprenaline and timolol on intraocular pressure was studied in conscious rabbits through changes of the dose-response curves. 2. Both drugs caused a dose-dependent fall of intraocular pressure mainly by reducing the aqueous humour formation. 3. When combined, timolol increased the response to submaximal concentrations of isoprenaline as well as EC50 (from 2.06 x 10(-3) M to 3.63 x 10(-3) M) and slope (from 1.21 to 1.89), but peak response to isoprenaline remained unchanged. 4. Discordance between experimental and theoretical additive curves as well as an interaction index smaller than 1 show that the interaction between both drugs is synergistic.  相似文献   
35.
The role of myelin basic protein (MBP) T cell recognition in the induction of experimental allergic encephalomyelitis (EAE) has been well established in mice and rats. A remarkable restriction has been observed in T cell receptor (TCR) genes utilized by encephalitogenic T cell lines (TCLs) specific for immunodominant epitopes in these species. Pathological similarities between this animal model and multiple sclerosis (MS) has led to consider MBP as a major candidate autoantigen in this human disorder. Unlike in inbred strains of animals, the T cell response to MBP in humans is quite heterogenous with regard to fine epitope specificity. The existence of V alpha and/or V beta restriction in MBP-specific T cells, from MS patients and healthy controls, is still a matter of debate. In this study we generated 77 MBP-specific TCLs from nine healthy donors and showed that peptide 7-27 is one of the most frequently recognized epitopes. 37% of all epitope-specific TCLs recognized this peptide and p7-27 specific TCLs were generated from seven out of the nine subjects studied. A high level of in vivo clonal expansion was observed in p7-27-specific TCLs in several subjects, which however is not specific of this epitope since this phenomenon was also observed in p85-104- and 149-162-specific TCLs.  相似文献   
36.
This paper presents the results of in vivo measurements on a worker from a fuel reprocessing plant who was involved in an actinide intake. The results revealed that false indications of an actinide lung burden could arise from a contaminant present elsewhere in the chest region. Consequently, it is important that lung monitoring programs for occupational workers handling actinides are conducted with this caution in mind and that due consideration is given even in cases of minor cuts/wounds in order to rule out substantial overestimation of internal radiation doses.  相似文献   
37.
We have previously shown that strychnine mimics the cytoprotective properties of glycine in renal proximal tubule (RPT) suspensions exposed to antimycin A (AA). The aims of this study were to determine whether the cytoprotective properties of strychnine applied to various types of nephrotoxicants and to examine the temporal aspects of the cytoprotection of glycine and strychnine. Tubular release of LDH activity was used as a marker of cell death. Glycine (2 mM) or strychnine (1 mM) added 5 min prior to the toxicant decreased LDH release in rabbit RPT suspensions exposed to 25 microM tetrafluoroethyl-L-cysteine (TFEC), 10 microM HgCl2, 0.5 mM t-butyl hydroperoxide (TBHP), or 0.2 mM bromohydroquinone (BHQ) for 4 hr, or 2 mM sodium cyanide (NaCN) for 2 hr. The relative rank order of effectiveness of glycine and strychnine was NaCN = TFEC > BHQ > DCVC > TBHP > HgCl2. The temporal aspects of strychnine and glycine protection were examined by exposing RPT to either AA or TFEC for 1 or 3 hr, respectively, and then adding either 1 mM glycine or 1 mM strychnine. Glycine and strychnine decreased LDH release in AA-treated RPT at 1.25 and 2 hr and TFEC-treated RPT at 4 hr. In addition, when RPT exposed to AA or TFEC and treated with strychnine or glycine were washed at either 1 or 4 hr, protection was eliminated at later time points. When glycine was added to RPT treated with either PCBC, TFEC, or DCVC 5 min prior to or 30, 60, 120, and 180 min following toxicant addition, LDH release was reduced at all time points. These results demonstrate that strychnine and glycine protect RPT from a variety of diverse nephrotoxicants, strychnine and glycine do not need to be present at the time of toxic insult, strychnine and glycine cytoprotection is reversible, and strychnine and glycine act in the late phase of necrotic cell injury.  相似文献   
38.
Combination therapies that include metronidazole (MTZ) are the most successful therapies used in eradicating Helicobacter pylori. In this study, the prevalence and the relevance of heterogeneity in susceptibility to MTZ among H. pylori populations of 156 patients were evaluated. The results of this study show that 37 patients (24%) were infected with MTZ-resistant H. pylori (MIC > or = 8 micrograms/ml). Furthermore, 33% (52 of 156) of the patients were found to be infected with H. pylori populations heterogeneous for their susceptibility to MTZ. The reassessment of the MICs of MTZ for these 52 H. pylori populations revealed MTZ resistance in 28 of them, increasing the number of MTZ-resistant H. pylori populations among the 156 patients to 65 (42%). Out of 20 isolates, 2 (10%) heterogeneous in their susceptibility to MTZ also appeared to be heterogeneous at the genome level as determined by randomly amplified polymorphic DNA fingerprinting. In conclusion, the results show the limitations and risk of possible misinterpretations when only a single colony, picked from the primary H. pylori populations isolated from patients, is analyzed for its susceptibility to MTZ.  相似文献   
39.
During a study of natural food colours, a simple and reliable high-performance liquid chromatography system was developed for use with cochineal and annato. An isocratic mobile phase, consisting of methanol and 6% aqueous acetic acid, resolved bixin and norbixin, while a gradient system was used to separate carminic acid and the annato compounds. The carminic acid contents of cochineal extract, carmine and carmine hydrosoluble were determined using an isocratic mobile phase (40:60, v/v). The detection limit for carminic acid in the various products was approximately 100 ng/g. Carminic acid was determined quantitatively in fruit beverages, yogurt and candies. It was demonstrated that, because of decomposition, carminic acid was not suitable for use in candies when manufacturing temperatures above 100 degrees C were required. Most membrane filters are not suitable for use with cochineal solutions, but a cellulose membrane filter did not adsorb carminic acid and was used successfully to remove impurities from water-based cochineal products and food extracts containing carminic acid.  相似文献   
40.
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