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11.
Although the influence of lung volume reduction surgery (LVRS) on incremental- and constant-power exercise is important in the evaluation of this procedure for patients with chronic obstructive pulmonary disease (COPD), it is rarely reported even in large randomised controlled trials. This report describes 39 patients with severe COPD ((mean +/- SE) forced expiratory volume in one second 32 +/- 2% pred, functional residual capacity 195 +/- 6% pred) who participated in a randomised controlled trial of LVRS and who completed incremental exercise tests at 6 months as well as endurance tests (constant power of 25 +/- 1 W) at 3, 9 and 12 months. Peak oxygen uptake (V'O2,pk) was similar between the treatment (n = 19) and control groups (n = 20) at baseline. After LVRS, the treatment group had a significantly greater V'O2,pk (mean difference (95% CI) 1.28 (0.07-2.50) mL x kg x min(-1)) and power (13 (6-20) W). The treatment group achieved a significantly greater minute ventilation (7.1 (2.9-11.3) L x min(-1)) with a greater tidal volume (0.16 (0.04-0.28) L). Baseline endurance was similar between groups. After surgery, there were significant between-group differences in endurance time, which were maintained at 12 months (7.3 (3.9-10.8) min). Lung volume reduction surgery is associated with an increase in exercise capacity and endurance, as compared with conventional medical treatment.  相似文献   
12.
Aims The Type 1 diabetes susceptibility locus, IDDM2, has been mapped to a variable number of tandem repeats (VNTR) region 5′ upstream of the insulin (INS) and insulin‐like growth factor (IGF2) genes on chromosome 11p15. The function of the VNTR is uncertain; however, it may influence the thymic expression of the insulin gene and affect the development of immune self‐tolerance. The aim of this study was to investigate whether the INS VNTR region is a Type 1 diabetes‐specific locus or acting as a general autoimmunity gene. Methods We genotyped the INS‐IGF2 VNTR [using the surrogate INS?23 HphI single nucleotide polymorphism (SNP)] in 823 Graves’ disease (GD)/multiple sclerosis (MS) families, 1433 GD/MS patients and 837 healthy control subjects. Results We found no evidence of excess transmission of the allele associated with Type 1 diabetes to individuals affected by GD or MS within the families. Analysis of the case–control dataset showed no genotypic or allelic difference between the two populations. Conclusions These data suggest that the INS‐IGF2 VNTR is acting as a Type 1 diabetes‐specific susceptibility gene rather than as an influence on general autoimmunity.  相似文献   
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AIMS: Autoimmune disorders co-exist in the same individuals and in families, implying a shared aetiology. The aim of this study was to compare the prevalence of the common autoimmune diseases in the parents of siblings from the Type 1 diabetes Warren repository with the general population. METHODS: Between 1989 and 1996, 505 British families with at least two siblings affected by Type 1 diabetes were recruited. Clinical information was collected regarding the presence of autoimmune disease in the parents and the prevalence of disease in the parents was compared with that expected in the general population. RESULTS: The prevalence of autoimmune disease in the parents was significantly higher in the repository compared with that expected in the general population [P-value = 1.98 x 10(-5) (female), P-value = 1.1 x 10(-8) (male)]. Type 1 diabetes was recorded in 63/1010 (6.2%) parents with a marked paternal preponderance (9.5 vs. 3%P = 0.002). Other autoimmune diseases affected 27% of parents with diabetes and 13.2% of parents without diabetes (P < 0.01). CONCLUSION: These data confirm the importance of family history as a significant risk factor for the development of Type 1 diabetes and support the hypothesis that the common autoimmune diseases share at least some aetiological mechanisms.  相似文献   
15.
BACKGROUND: We have observed that dosimeter-run nebulizers have a much smaller output when manually activated than when breath activated; however, this has not been adequately investigated. OBJECTIVE: To evaluate the effect of different calibration methods on nebulizer output. METHODS: Six healthy subjects performed all calibrations. The nebulizers were operated by 2 different dosimeters and were calibrated to produce 9 microL per actuation by breath activation followed by exhalation to the room. The nebulizers were then operated at these identical settings, and the output determined in 3 ways: (1) breath activation followed by exhalation to the room, (2) breath activation with exhalation into the nebulizer, and (3) manual activation (with no subject using the nebulizer). These 3 methods were termed regular, rebreathe, and manual, respectively. RESULTS: There was a large and statistically significant difference in nebulizer output among the 3 methods. The measured rebreathe outputs (5.6 and 5.7 microL per actuation) were approximately two thirds and the manual outputs (3.2 and 3.9 microL per actuation) were approximately one third of the regular calibration outputs (8.6 and 8.9 microL per actuation); the 2 values are for the 2 dosimeters. The results were highly statistically significant (P < .001). CONCLUSIONS: The method by which a nebulizer-dosimeter system is calibrated results in different nebulizer outputs. This has a high likelihood of influencing the concentration of methacholine causing a 20% decrease in volume in the first second of forced expiration.  相似文献   
16.
Plasma, heart, and extracardiac tissue verapamil concentrations were measured after sustained intravenous infusions in 11 dogs to determine the differential tissue accumulation of verapamil. A steady state verapamil concentration of 327 +/- 50 ng/ml decreased the mean arterial blood pressure from 104 +/- 9 to 90 +/- 6 mm Hg (p = 0.08) and the P-R interval increased from 118 +/- 4 to 176 +/- 13 ms (p less than 0.001) with second-degree atrioventricular block developing in 6 animals. Verapamil accumulated in organs in the following order: Lung much greater than kidney greater than spleen greater than ventricular myocardium = liver greater than atrial myocardium greater than cerebral cortex greater than fat = skeletal muscle. Levels in the ventricular free wall were consistently greater than atrial levels, but no difference was observed between left versus right-sided cardiac chambers. In summary, affinity of different organs for verapamil is highly variable and organ-specific; furthermore, differential intracardiac chamber accumulation occurs.  相似文献   
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18.
One hundred forty five individuals who sought medical attention as a result of a motor vehicle accident (MVA), and who were initially assessed 1 to 4 months post-MVA, were followed up prospectively for 6 months to determine how many of the 55 with posttraumatic stress disorder (PTSD) and the 43 with sub-syndromal PTSD would remit and what variables would predict remission. Thirty (55%) of those with initial PTSD had remitted at least in part by 6 months while 67% of those with sub-syndromal PTSD had remitted (and 5% had worsened). Four variables, including severity of initial symptoms, degree of initial physical injury, relative degree of physical recovery by 4 months and whether a close family member suffered a trauma during the follow-up interval, combined to classify 6-month clinical status of 84% of those with initial PTSD secondary to MVAs.  相似文献   
19.
Intensive chemotherapy for peripheral T-cell lymphomas.   总被引:3,自引:0,他引:3  
Forty-two patients with previously untreated peripheral T-cell lymphomas (PTCL) were treated with an intensive chemotherapy protocol. Either the BACOP or the m-BACOD regimen was used for induction. Patients achieving complete clinical remission after three courses were given intensive consolidation and maintenance chemotherapy similar to the L10/L17M protocol designed by the Memorial Sloan-Kettering Group for acute lymphoblastic leukemia and lymphoblastic lymphoma. There were 27 (64 per cent) males and 15 (36 per cent) females. The median age was 54 years (mean 53, range 15 to 68). Seven of them (17 per cent) had stage I disease, four (10 per cent) stage II, seven (17 per cent) stage III and 24 (57 per cent) stage IV. Eighteen patients (43 per cent) had B symptoms and four (10 per cent) had bulky disease. According to the Working Formulation, the histology was diffuse mixed in 16 patients (38 per cent), diffuse large cell in 18 (43 per cent), diffuse immunoblastic in four (10 per cent) and unclassifiable in four (10 per cent). According to a modified Japanese Lymphoma Study Group's classification, the histology in 24 patients (57 per cent) was the pleomorphic type, in 13 (31 per cent) immunoblastic-lymphadenopathy-like (IBL-like), and in five (12 per cent) unclassifiable. The overall complete remission rate was 67 per cent. Twenty-five per cent of the complete responders relapsed and the DFS of the CR patients was 62 per cent at three years. The overall survival of all patients at three years was 52 per cent. Patients with stage I, II and III disease had significantly better CR rate (100 per cent versus 42 per cent, p = 0.001) and overall survival (82 per cent versus 35 per cent at three years, p = 0.01) than those with stage IV disease but the relapse rate and DFS of CR patients were similar. This study shows that the prognosis of patients with PTCL can be improved by intensive therapy.  相似文献   
20.
CONTEXT: Vaccine-preventable diseases among adults are major contributing causes of morbidity and mortality in the United States. However, adult immunizations continue to be underutilized in both urban and rural areas. PURPOSE: To evaluate the effectiveness of a community-wide education campaign and mailed reminders promoting pneumococcal immunizations to rural Medicare beneficiaries. METHODS: We implemented a community-wide education campaign, and mailed reminders were sent to Medicare beneficiaries in 1 media market in Montana to increase pneumococcal immunizations. In a second distinct media market, mailed reminders only were sent to beneficiaries. FINDINGS: The proportion of respondents aged 65 years and older aware of pneumococcal immunizations increased significantly from baseline to follow-up among respondents both in the education-plus-reminder (63% to 78%, P = 0.04) and the reminder-only (64% to 74%, P = 0.05) markets. Overall from 1998 to 1999, there was a 3.7-percentage-point increase in pneumococcal immunization claims for Medicare beneficiaries in the education-plus-reminder market and a 1.5-percentage-point increase in the reminder-only market. Medicare beneficiaries sent reminders in the education-plus-reminder market compared to those in the reminder-only market were more likely to have a claim for pneumococcal immunization in 1999 (odds ratio 1.18, 95% confidence interval 1.08 to 1.28). The results suggest that these quality improvement strategies (community education plus reminders and reminders alone) modestly increased pneumococcal immunization awareness and pneumococcal immunization among rural adults. Mailed reminder exposure was associated with an increased prevalence of pneumococcal immunizations between 1998 and 1999 and was augmented somewhat by the education campaign.  相似文献   
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