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A fibre optic potassium ion sensor has been developed based on reflectance measurements of the pH-dependent chromogenic crown ether 'Takagi reagent' immobilized on the non-ionic polymeric resin Amberlite XAD2. The sensor response is in the 1.5-100 mM range with a detection limit of 0.25 mM K+. The selectivity factor over sodium is 20. The proposed sensor works with a reproducibility of +/- 0.8% at the 5 mM K+ level. Advantageous design features include ease of construction, simplicity of use, reversibility, short response time (approximately 1 min) and an optimum working pH range (7.0-8.0) for biological fluids. This optical sensor was applied successfully to the direct determination of potassium in human serum. Aqueous potassium standards containing 0.13 M NaCl and a buffer of pH 8 were used for calibration.  相似文献   
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Congenital fistulae between the tracheobronchial tree and oesophagus usually originate from the lower end of the trachea or right main bronchus. The case history is presented of a man in whom a fistula between the oesophagus and left main bronchus was not diagnosed until the age of 48.  相似文献   
25.
BACKGROUND: The aim of the present study was to analyze the effects of a qigong training program on blood biochemical parameters. MATERIAL/METHODS: Twenty-nine healthy subjects participated in the study of whom 16 were randomly assigned to the experimental group and 13 to the control. The experimental subjects underwent daily qigong training for one month. Blood samples for the quantification of biochemical parameters (total cholesterol, HDL, LDL, triglycerides, phospholipids, GOT, GPT, GGT, urea, creatinine) were taken before and after the training program. As statistical analysis, ANCOVA was performed. RESULTS: Statistically significant differences were found showing that the experimental group had lower serum levels of GOT (glutamic-oxaloacetic transaminase), GPT (glutamic-pyruvic transaminase), and urea and that there was a trend towards significance in GGT (gamma-glutamyltransferase). CONCLUSIONS: This study demonstrates that after practicing qigong for the short period of one month, noteworthy changes in several blood biochemical parameters were induced. While it is tempting to speculate on the relevance and implications of these biochemical variations, further investigation is needed to elucidate the scope of these findings.  相似文献   
26.
The present study was carried out to evaluate the changes in digitoxin kinetics during ampicillin administration. Subjects were informed of the nature of the study and the treatment was applied to those who gave their written consent. Six healthy volunteers received a single oral dose of 1.0 mg of digitoxin. Three days later, they were given orally ampicillin trihydrate, 500 mg four times daily, for five consecutive days. Blood samples were taken at 24, 36, 48, 60, 72, 96, 120, 144, 168 and 192 hours after digitoxin. Compliance with ampicillin regimen was verified by fluorimetric measurement of serum ampicillin. Concentrations of serum digitoxin were determined by radioimmunoassay. The mean digitoxin elimination half-life changed from 162.8 +/- 12.9 h before to 181.3 +/- 10.1 h (mean +/- s.e. mean) after ampicillin. These differences were not significant. No consistent evidence of a kinetic interaction between digitoxin and the broad-spectrum antibiotic ampicillin was found.  相似文献   
27.
CONTEXT AND OBJECTIVE: Adverse drug reactions are a significant problem in patients on antiretroviral therapy (ART). We determined liver enzyme elevation frequencies in HIV-infected children and adolescents receiving ART, and their association with risk factors. DESIGN AND SETTING: Cross-sectional study, at the Pediatrics Immunodeficiency Division, University Hospital, Universidade Estadual de Campinas. METHODS: Medical records of 152 children and adolescents (54.6% male; median age 7.48 years) were analyzed, with a mean of 2.6 liver enzyme determinations per patient. Clinically, patients were classified in categories N (6), A (29), B (78) and C (39). Serum levels of aspartate aminotransferase and alanine aminotransferase were evaluated. Hepatotoxicity was scored as grade 1 (1.1-4.9 times upper limit of normality, ULN), grade 2 (5.0-9.9 times ULN), grade 3 (10.0-15.0 times ULN) and grade 4 (> 15.0 times ULN). To assess hepatotoxicity risk factors, odds ratios (OR) and adjusted odds ratios (aOR) for age, gender, TCD4+ cell count, viral load and medication usage were calculated. RESULTS: We observed grade 1 hepatotoxicity in 19.7 % (30/152) patients. No cases of grade 2, 3 or 4 were detected. There was a significant association between hepatotoxicity and use of sulfonamides (OR, 3.61; 95% confidence interval (CI), 1.50-8.70; aOR, 3.58; 95% CI, 1.44-8.85) and antituberculous agents (OR, 9.23; 95% CI, 1.60-53.08; aOR, 9.05; 95% CI, 1.48-55.25). No toxicity was associated with ART. CONCLUSIONS: One fifth of patients experienced mild hepatotoxicity, attributed to antituberculous agents and sulfonamides. Our results suggest that ART was well tolerated.  相似文献   
28.
Miconazole and econazole, two fungicide imidazole derivatives, completely inhibited growth of Trypanosoma cruzi (Tulahuen strain) at concentrations of about 20 muM. Culturing of T. cruzi in the presence of lower doses of imidazole derivatives produced: decrease of 5,7-diene sterol content in epimastigotes (including ergosterol); disappearance of the nuclear chromatin, vacuolization and decrease in the electron density of the cytoplasm; selective surface alterations as revealed by an increased response to wheat-germ- and phytohemagglutinin. At variance with the effect of miconazole on Candida (De Nollin et al. (1977) Antimicrobial. Agents Chemother. 11, 500-513), miconazole and econazole, under the experimental conditions used, did not increase the rate of hydrogen peroxide generation by T. cruzi.  相似文献   
29.
In patients with mesiotemporal sclerosis, posterior hippocampal involvement at the ictal onset is not associated with an excellent outcome. A study confirmed that ictal onset in the posterior parahippocampal gyrus is associated with a less favorable outcome compared with ictal onset in the anterior parahippocampal gyrus in patients with mesiobasal temporal lobe epilepsy who are undergoing foramen ovale recording. The authors hypothesized that involvement of the two medial contact points of posterior basal temporal subdural (SD) strip at the ictal onset, representing ictal onset in the posterior parahippocampal gyrus, may also adversely influence the surgical outcome. With this objective, the authors assessed the incidence of posterior basal temporal SD strip (the two medial contact points) involvement at the ictal onset in patients with mesiotemporal sclerosis and determined whether presence of this finding influenced surgical outcome. Thirty-six patients with mesiotemporal sclerosis underwent a single SD grid (lateral frontotemporal) and strips (three basal temporal and one orbitosubfrontal) monitoring. Based on the earliest involvement of basal temporal strips (the two medial contact points) during the seizure, patients were classified into (1) anterior and/or middle basal temporal, or (2) posterior basal temporal (with or without involvement of anterior and/or middle basal temporal) ictal onset groups. A temporal lobectomy with adequate resection of the ictal onset zone was performed in all patients. Surgical outcome was based on Engel's classification. Six of 36 (17%) patients were classified into the posterior basal temporal ictal onset group. Only two patients from the posterior basal temporal ictal onset group experienced a good outcome compared with 26 of 30 patients from anterior and/or middle basal temporal ictal onset group (P = 0.01). In patients with mesiotemporal sclerosis who were monitored with SD electrodes, involvement of the two medial contact points of posterior basal temporal strip at the ictal onset (representing ictal onset in the posterior parahippocampal gyrus) occurred in 17% of the patients. These patients might not experience an excellent surgical outcome despite including the ictal onset zone in resection. These findings may be useful in presurgical counseling of patients with mesiotemporal sclerosis who undergo intracranial SD monitoring.  相似文献   
30.
E Roman  C Moreno 《Immunology》1997,90(1):52-56
Four synthetic peptides bearing dominant CD4+ T-cell epitopes of the 19,000 and 38,000 MW proteins of Mycobacterium tuberculosis were used to provoke a delayed-type hypersensitivity (DTH) reaction in mice previously immunized with recombinant 19,000 and 38,000 MW proteins. It was found that an effective enhancement of the DTH reaction was obtained if the peptides were administered as a complex with M. tuberculosis hsp 70 protein. The increase in reactivity was not obtained when hsp 70 and peptide were co-injected at the same site, but not in complex, or when the specific peptide was displaced from the complex by an irrelevant peptide with high capacity to bind hsp 70. One of the antigenic peptides whose capacity to complex with hsp 70 is low, failed to show the enhancement of DTH when injected together with hsp 70.  相似文献   
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