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51.
Salmeterol tachyphylaxis in steroid treated asthmatic subjects.   总被引:5,自引:2,他引:3       下载免费PDF全文
H Booth  R Bish  J Walters  F Whitehead    E H Walters 《Thorax》1996,51(11):1100-1104
BACKGROUND: Tachyphylaxis to the protection afforded by salmeterol to broncho-constrictor stimuli after regular use has been described in patients with mild asthma not receiving inhaled corticosteroids. The present study was performed to investigate whether airway tachyphylaxis occurs in symptomatic asthmatic subjects receiving inhaled corticosteroids, the group for whom salmeterol is recommended in clinical practice. METHODS: Thirty one adult patients with symptomatic chronic asthma who were receiving inhaled corticosteroids were randomised in a double blind manner and on a 2:1 basis to receive salmeterol 50 micrograms (n = 22) or placebo (n = 9) twice daily. Baseline forced expiratory volume in one second (FEV1) was measured during the run-in period, on day 0, and after four and eight weeks of regular treatment (following a 36 hour test drug washout period). Airway responsiveness to methacholine was measured one hour after administration of the test drug on these occasions. Diary cards were kept throughout the study and for a two week follow up period. RESULTS: Baseline FEV1 was not significantly different between the treatment groups or between visits. There was significant bronchodilatation one hour after salmeterol administration at 0, four, and eight weeks. No significant tachyphylaxis of the bronchodilator action of salmeterol was seen. Protection against methacholine induced bronchoconstriction reduced from 3.3 doubling dilutions after the first dose of salmeterol to two doubling dilutions after four and eight weeks of regular treatment. Symptom scores and "rescue" salbutamol use were significantly reduced during salmeterol treatment and daytime improvements were maintained into the follow up period. CONCLUSIONS: Inhaled corticosteroids did not prevent tachyphylaxis to the protection afforded by salmeterol to methacholine induced bronchoconstriction. The clinical significance, if any, of these findings remains to be defined.  相似文献   
52.
Previously divorced and remarried couples have a higher probability of divorce and decline in marital quality. Models which have explained this behavior focus on: willingness to leave marriage; selection; socioeconomic status; the remarriage market; and incomplete marriages. Each model is examined among a population of marrieds and remarrieds to distinguish attributes and the extent to which these attributes increase the probability of decline in marital quality or divorce. Data were obtained from a sample of 2033 marrieds 55 years old who were interviewed over the telephone in 1980, 1983, and 1988 in the Marital Instability Over the Life Course Study. Incomplete marriage was measured by whether and to what extent parents or parents-in-law made contact and the number of relatives that party was close to. Willingness to leave was based on attitudes to divorce and the ability to handle emotion and financial affairs if the marriage ended. Selection referred to poor marriage material (drugs or alcohol, criminal conduct, mismanagement of money, immature behavior. Socioeconomic status was reflected in occupational status, educational levels, and income. The marriage market was a measure of age, education, and religious differences. Marital quality was examined in terms of happiness, interaction, disagreement, and divorce proneness. Multiple classification analysis was used to compare attributes by marital history. The methods of Kessler and Greenberg were used to examine changes in marital quality over time in first time marriages and remarriages. The results indicate that individuals in remarriages have relationships with attributes which potentially lower marital quality and increase the probability of divorce. When both individuals have prior marriage and divorce experience, there is even lower social integration, greater willingness to leave marriage, higher probability of marrying as a teen, lower socioeconomic status, and greater likelihood of age differences. Remarriage variables and marital quality variables both showed linear relationships. Remarriage variables and marital quality variables both showed linear relationships. In the cross sectional analysis of the 1980 data there is a statistically significant relationship with attributes which potentially lower marital quality in 1980 indicates remarried persons are more prone to lower marital quality than people in first marriages.  相似文献   
53.
Patients (N = 100) who had been admitted to behaviorally oriented residential treatment for their drinking problems were followed up for 1 year. A treatment goal option of controlled drinking was explicitly catered for. Overall outcome, in which 27% of those available for follow-up were categorized as "successful," 35% as "equivocal" and 38% as "failure," does not appear to be markedly dissimilar to that reported from other agencies. The distribution of approximately equal abstinent and nonabstinent successful outcomes is similar to that found following treatment programs that promote a single goal. Sociodemographic variables were less influential in predicting outcome than were treatment variables--with frequency of aftercare attendance being particularly significant. Those who had received previous hospital treatment for their problem, those who habitually drank in company and those who had abnormal blood test results prior to entering treatment had poorer outcome.  相似文献   
54.
Growth of vascularized composite mandibular allografts in young rabbits   总被引:2,自引:0,他引:2  
Forty-one hemimandible allografts were transplanted in young rabbits immunosuppressed with cyclosporine. The majority of the grafts demonstrated normal wound healing, and growth of hair, bone, and teeth. The mandibular body and the premolars showed significant growth in length. The allografted mandibles functioned sufficiently that the rabbits took oral nourishment soon after surgery. Long-term survival was limited by a toxic "wasting syndrome" specific for rabbits under treatment with cyclosporine.  相似文献   
55.
Through the use of an antibiotic-impregnated polymethylmethacrylate spacer block in two-stage exchange arthroplasty, the chronically infected total knee arthroplasty can, in most cases, be effectively salvaged. In a review of 28 such consecutive cases by a single surgeon, all revised implants were retained except one which required arthrodesis. In the remaining cases, mean Hospital for Special Surgery knee scores were 86, with mean total range of motion of 90 degrees . All wounds healed eventually, and seven patients were thereafter able to undergo other total joint arthroplasties. Advantages of this technique included maintenance of ligamentous balance as well as bone stock with weight bearing, local antibiotic delivery, and facilitation of reimplantation.  相似文献   
56.
Objectives: To describe the physical growth patterns of infants born to narcotic dependent mothers (INDM) over a 12 months period and, if possible, to relate the growth to drug taking patterns during pregnancy.
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM.  相似文献   
57.
This study was designed to look at the differences in visuospatial abilities between boys and girls before they can speak fluently. At the mandatory two year follow up visit, children were given the opportunity to build a tower and a bridge. In children whose birth weight was > or = 2500 g, the capacity for erecting a tower was the same in both sexes, but for building a bridge striking differences were noted according to their sex. Among the 376 children of this category, 41 out of 199 boys (21%) were able to build a bridge in comparison with 15 out of 177 girls (8%). This difference is highly significant. In children whose birth weight was < or = 2500 g, no differences were noted either for building a tower or a bridge. By showing that boys outnumber girls among the most skilled toddlers in spatial abilities, this work confirmed the action of a male related factor on cerebral lateralisation.  相似文献   
58.
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.  相似文献   
59.
60.
The frequency of chromosomal aberrations in peripheral blood lymphocytes was assessed in three groups of children: untreated coeliac disease (n = 20); non-coeliac disease enteropathies (n = 15); controls (n = 15). The mean frequency of aberrant cells and the total number of aberrations per 100 metaphases was increased in the coeliac disease group compared with controls by factors of 5 and 6, respectively (p < 0.01 for both). Aberrant cells and total aberrations were similarly increased in the non-coeliac disease enteropathy group by a factor of 3.7 in each case (p < 0.05). However, the frequency of aberrations in the two enteropathy groups was not significantly different. Children with coeliac disease, similar to affected adults, have evidence of increased chromosomal instability. However, similarly increased chromosomal aberrations are seen in children with non-coeliac disease enteropathies, indicating that the abnormality is not specific for coeliac disease.  相似文献   
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