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61.
The relationship between the amount of inhaled steroids delivered from pressurized metered-dose inhalers used with their recommended holding chambers and age of the patients using these devices was studied in an open randomised cross-over filter study. We recruited 1-2-month-old healthy infants (n = 21), 2-3-year-old asthmatics (n = 13), 4-6-year-old asthmatics (n = 15), and 10-15-year-old asthmatics (n = 20). Each child inhaled two puffs, administered by a single investigator, of both budesonide through Nebuchamber and fluticasone propionate through Babyhaler, on two occasions. Moreover, the 4-6-year-old group inhaled via both facemask and mouthpiece. Drug, collected on a filter interposed between holding chamber and patient, was analysed by high performance liquid chromatography. Filter dose, expressed in percent of the nominal dose, was analysed in a mixed effect linear regression model with age group, holding chamber and inhalation interface (facemask or mouthpiece) as fixed effects and subject as random effect. Filter dose from both holding chambers increased significantly with age, from 3% with Babyhaler and 7% with Nebuchamber in the youngest children, to 40-41% with both holding chambers in adolescents. Nebuchamber delivered more drug than Babyhaler (p = 0.002), but variability in drug delivery (about 11%) was similar between holding chambers. Filter dose decreased from 35% to 22% with Babyhaler, and from 42% to 27% with Nebuchamber when using a mouthpiece rather than a facemask (p < 0.0001). Delivery of inhaled steroids used with their recommended holding chambers depends from age and holding chamber, but also from the inhalation interface. Lung deposition and clinical studies comparing inhalation from holding chambers with mouthpiece and facemask are urgently required.  相似文献   
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63.
This is a retrospective analysis of 5037 patients with squamous cell carcinoma of the nasopharynx treated during the years 1976-1985. The stage distribution according to Ho's classification was 9% Stage I, 13% II, 50% III, 22% IV, and 6% Stage V. Only 4488 (89%) patients had a full course of megavoltage radiation therapy. The median equivalent dose to the nasopharyngeal region was 65 Gy and cervical region in node-positive patients 53 Gy. Seventy percent (906/1290) of the node-negative patients had no prophylactic neck irradiation. The overall actuarial 10-year survival rate was 43%, and the corresponding failure-free survival 34%. Altogether, 4157 (83%) patients achieved complete remission lasting more than 6 months, but 53% (2205/4157) of them relapsed after a median interval of 1.4 years. The 10-year actuarial local, regional, and distant failure-free rates were 61%, 64%, and 59%, respectively. Thirty-eight percent (338/891) of all patients with local recurrence achieved second local remission. The local complete remission rate with aggressive re-irradiation alone was 47% (333/706). But 37% (124/338) of the responders recurred the second time. The incidence of distant failure correlated significantly with both the N-stage and the T-stage, with the highest (57%) occurring in patients with N3 disease. The incidence of nodal relapse in node-negative patients was 11% (44/384) among those given prophylactic neck irradiation, but 40% (362/906) among those without. Therapeutic irradiation achieved a complete regional remission rate of 90% (306/339). However, despite successful salvage, these patients had a significantly higher distant failure rate than those without nodal relapse, even if they remained local-failure-free (21% vs 6%). Patients treated during 1981-1985 achieved significantly better treatment results than those treated during 1976-1980, especially in terms of the overall survival (57% vs 47% at 5-year), the overall failure-free survival (42% vs 35% at 5-year), and the local failure-free rate (70% vs 63% at 5-year). The possible contributing factors are discussed.  相似文献   
64.
65.
The combinations of ampligen and zidovudine at ratios of 100:1, 25:1, 10:1, and 1:50 acted synergistically to reduce cytopathology caused by HIV in MT-2 cell cultures. Combination indices were less than 1 at all of these ratios representing different combinations of concentrations and at 3 effective doses (ED30, ED50, ED70). Combination of drugs which show synergism at a wide range of ratios of combinations suggest that they may be useful clinically, and that the antiviral efficacy of ZDV may be increased in combination with ampligen. Synergism was also found between ampligen and zidovudine by reduction of HIV-produced plaques in a HeLa cell line expressing CD-4 receptors. However the combination of ampligen and dideoxyinosine against HIV in MT-2 cells was only additive and not synergistic.  相似文献   
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67.
BACKGROUND: Reactive oxygen species may contribute to the pathogenesis of asthma. Functional genetic polymorphisms of antioxidant enzymes, superoxide dismutase (SOD) and catalase are good candidates for asthma susceptibility. OBJECTIVE: To investigate the association of the manganese-containing form of SOD (MnSOD) gene at amino acid position 16 (Val16Ala) and catalase gene in the promoter at A-21T and C-262T polymorphisms and asthma in a Hong Kong Chinese population. METHODS: The association study was conducted in a case-control design in asthma patients (n=251) and healthy controls (n=316) by genotyping. The functional significance was assessed by determining erythrocyte SOD and catalase activity. RESULTS: The Val allele of MnSOD at Val16Ala and the A allele of catalase gene at A-21T were not different between patients and controls, while the C allele of catalase gene at C-262T was found to be significantly different between patients and controls (P=0.033). The less frequent variant of catalase gene (-262T) was found to be protective from the development of asthma in a Hong Kong Chinese non-smoking population (adjusted odds ratio=0.35, 0.15-0.85; P=0.017). Asthma patients had elevated erythrocyte SOD and catalase activities in comparison with healthy controls (P<0.01). However, their activities were not associated with different genotypes within healthy controls or asthma patients. CONCLUSION: This is the first report showing that SOD and catalase functional activities are not associated with their respective genetic polymorphisms but related to the presence of asthma in a Hong Kong Chinese population.  相似文献   
68.
Autoaugmentation mammaplasty of the small ptotic breast with adjacent pedicled fat and simultaneous correction of ptosis is presented. The operative procedure is described and some representative results are shown.  相似文献   
69.
Nucleotide 6724 of the factor VIII gene harbors a polymorphism of low frequency. A report from Taiwan claimed that 97.9% of the 83 alleles examined were of the A nucleotide at this position, which is quite different to the data from Western populations. Furthermore, this nucleotide is the start of exon 25, located in juxtaposition to the splicing acceptor of intron 24. We wonder if the nucleotide change at this location might have any effect on the splicing process of pre-mRNA. Using genomic DNA with direct sequencing of the polymerase chain reaction-amplified intron 24/exon 25 junction site, we found that 59 of the 60 patient samples were of the GTG sequence at nucleotides 6724-6726. The polymorphism is similar between populations in Taiwan and Western countries. The sequence of intron 24 around the splicing acceptor was always TCCAACTCTATTGCCCTCAG (-20 to -1), except for one hemophiliac patient who had a mutation in which the absolute consensus AG doublet of the intron 24 splicing acceptor changed to the AA dinucleotide. Owing to the mutation, exon 24 was erroneously spliced to exon 26, and exon 25 was skipped. This finding further testifies to the importance of the invariant AG dinucleotide in the example of the factor VIII gene.  相似文献   
70.
Sir, In their article, Shankar and colleagues underline the significantburden of tuberculosis within their population and the importanceof identifying latent infection  相似文献   
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