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Sonazoid is a new contrast agent for ultrasound imaging comprising an aqueous suspension of lipid-stabilised perfluorobutane (PFB) gas microbubbles. A respiration-metabolism chamber system was developed to collect exhaled air following intravenous administration of Sonazoid to rats. Analysis of PFB in the exhaled rat air was performed using a modified version of an earlier published method for blood samples, i.e. an automatic headspace gas chromatographic mass spectrometric (GC-MS) method using electron impact ionisation. The calibration standards were PFB diluted in air (2.5-1800 pg/ml). Perfluoropentane (PFP) was used as an internal standard and the MS detector was set to single ion monitoring of the base fragment ions of PFB (m/z 69 and 119) and PFP (m/z 69). The calibration curve, made by plotting the peak area ratios of PFB (m/z 69) to PFP (m/z 69) against the theoretical concentration of PFB, was fitted to a linear equation with weighting 1/y2 and found to be reproducible. The lower limit of quantification (LLOQ) was 2.5 pg PFB/ml. The between-day variation of the method was below 2.6% relative standard deviation (R.S.D.) and the within-day variation of the method was below 6.4% R.S.D. The accuracy of the method was evaluated and showed a relative error less than 5.2%. PFB was found to be stable for 14 days when stored in Tedlar sample bags at room temperature. An even lower detection limit may be obtained by using the more time-consuming process of solid-phase micro extraction; thus, by concentrating PFB on carboxen-PDMS fibres an LLOQ of 0.5 pg PFB/ml was obtained. When five rats were given an i.v. bolus injection of Sonazoid at a dose of 8 microl microbubbles/kg a mean recovery of 96% (range, 81-110%) was found during 24 h; more than 50% was exhaled during the first 30 min after injection.  相似文献   
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BCG Antibody Profiles in Tuberculoid and Lepromatous Leprosy   总被引:11,自引:9,他引:11       下载免费PDF全文
In sera from 12 patients with polar tuberculoid leprosy, 12 with subpolar tuberculoid leprosy, and 16 with lepromatous leprosy were demonstrated a total number of 125 anti-BCG precipitins by means of crossed immunoelectrophoresis with intermediate gel. Up to 14 different precipitins were found in individual sera, and the complexity in antibody response was higher than previously realized. The specificity of 69% of the antibodies was defined, and these antibodies were titrated in three arbitrary titer units. A highly significant difference (P < 0.002) was found in antibody response between the tuberculoid and the lepromatous group. Due to simplicity, sensitivity, and high resolution, the method used is a promising tool for providing exact data to be used as guidelines for purification of important individual mycobacterial antigens. The need for reference antisera is emphasized.  相似文献   
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Forty-three patients who had been treated in hospital for major depression were studied 1 to 2 years after discharge. Patients retrospectively ranked physical exercise as the most important element in the comprehensive treatment programme. Most subjects continued with regular exercise after discharge, and most of these exercised aerobically at least 2 h a week. Exercisers tended to have lower depression scores at follow-up examination than nonexercisers.  相似文献   
47.
ObjectiveA variety of measures are used for reporting levels of compulsory psychiatric hospitalisation. This complicates comparisons between studies and makes it hard to establish the extent of geographic variation. We aimed to investigate how measures based on events, individuals and duration portray geographical variation differently and perform over time, how they correlate and how well they predict future ranked levels of compulsory hospitalisation.MethodsSmall‐area analysis, correlation analysis and linear regressions of data from a Norwegian health registry containing whole population data from 2014 to 2018.ResultsThe average compulsory hospitalisation rate per 100,000 inhabitant was 5.6 times higher in the highest area, compared to the lowest, while the difference for the compulsory inpatient rate was 3.2. Population rates based on inpatients correlate strongly with rates of compulsory hospitalisations (r = 0.88) and duration (r = 0.78). 68%–81% of ranked compulsory hospitalisation rates could be explained by each area''s rank the previous year.ConclusionThere are stable differences in service delivery between catchment areas in Norway. In future research, multiple measures of the level of compulsory hospitalisation should ideally be included when investigating geographical variation. It is important that researchers describe accurately the measure upon which their results are based.  相似文献   
48.

Objective

To compare the effectiveness of tumor necrosis factor (TNF)–blocking agents (etanercept and infliximab) in patients with rheumatoid arthritis (RA) and patients with ankylosing spondylitis (AS).

Methods

Data from an ongoing longitudinal, observational study in Norway were used to assess changes in health‐related quality of life (HRQOL) in patients with RA (n = 291) and AS (n = 62). Patients received anti‐TNF therapy, and changes in scores on the Short Form 36 (SF‐36), SF‐6D, modified Health Assessment Questionnaire, and visual analog scales for patients' assessments of pain, fatigue, and global status from baseline to followup examinations at 3 and 6 months were compared. Data were adjusted for age, sex, and baseline values and are presented as crude estimates as well as standardized response means.

Results

Both groups had improvements in all measures at 3 and 6 months. At 3 months, the changes were significantly better in the AS group compared with the RA group for all measures except the SF‐36 social functioning scores. At 6 months, all changes were numerically greater in the AS group. Differences were significant for the SF‐36 role emotional scores and were borderline significant for the SF‐36 physical functioning, role physical, and vitality scores and for the SF‐6D scores.

Conclusion

In this real‐life setting, patients with AS experienced improvement in HRQOL that was comparable to, and sometimes greater than, that observed in RA patients. These results support the idea that patients with AS should have the same access to TNF‐blocking agents as patients with RA.
  相似文献   
49.
Background and aim: Vitamin D deficiency is common in inflammatory bowel disease (IBD). The aims of the present study were to determine the prevalence of vitamin D deficiency and to identify clinical and epidemiological variables associated with vitamin D deficiency in an outpatient population with IBD.

Methods: Participants were recruited from nine hospitals in the southeastern and western regions of Norway as part of an observational, multicentre study from March 2013 to April 2014. Clinical and epidemiological data were collected by interview and from medical records. All analyses of serum 25-hydroxyvitamin D (25-OH-D) were performed in the same laboratory.

Results: In total, 49% (200/408) of the patients had a 25-OH-D concentration <50?nmol/L, including 53% (122/230) of the Crohn’s disease (CD) patients and 44% (78/178) of the ulcerative colitis (UC) patients. In CD patients, disease activity, measured as the HBI, was inversely associated with vitamin D deficiency. No such association was observed with the Simple Clinical Colitis Activity Index (SCCAI) scores in UC, but in UC patients, vitamin D deficiency was associated with elevated faecal calprotectin >100?mg/kg. In patients with CD, there were significantly more relapses during the previous year in patients with vitamin D deficiency.

Conclusions: Vitamin D deficiency was common, especially in CD, and was associated with increased disease activity, a relapsing disease course and higher inflammatory activity.  相似文献   
50.
A major issue in the care of terminally ill patients is communication and information provision. This paper reports the extent to which physicians in Australia, Belgium, Denmark, Italy, the Netherlands, Sweden and Switzerland discuss topics relevant to end of life care with terminally ill patients and their relatives (without first informing the patient), and possible associations between physician-specific characteristics and such discussions. Response rates to the postal survey ranged from 39% to 68% (n =10139). Physicians in most of the countries except Italy ;in principle, always' discuss issues related to terminal illness with their patients but not with patients' relatives without first informing the patient, unless the relatives ask. Cross-national differences remained strong after controlling for physician characteristics. The majority of physicians appeared to support the principle of patient-centred care to terminally ill patients, consistent with palliative care philosophy and with the law and/or professional guidelines in most of the countries studied.  相似文献   
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