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The “in vivo” effect of Inmunoferon (AM3) on the production of interferon (IFN) and natural killer (NK) activity in young and old mice was studied. Although AM3 is not an IFN inducer by itself, enhancements in the serum IFN levels were produced when drug was associated to Newcastle disease virus or bacterial lipopo-lysaccharides as IFN inducers. This effect appeared to be dependent on the time lapsed between the inducer agent and drug. In addition, a significant stimulating effect on NK cell activity was also produced by AM3 treatments. This effect could be a consequence of a marked IFN induction and/or a modifying effect in prostaglandin synthesis.  相似文献   
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BACKGROUND. Detection and treatment for rejection after transplantation are based on the identification of myocyte damage upon endomyocardial biopsy. Noninvasive detection of such damage is possible with 111In-labeled monoclonal antimyosin antibodies (MAA). Although the presence and degree of MAA uptake parallels the rejection activity detected by biopsy, the relation between the degree of uptake and the occurrence of severe rejection-related complications has not been previously assessed. METHODS AND RESULTS. Two hundred forty-seven MAA studies were performed coinciding with biopsies in 52 patients 1-71 months after transplantation. A heart-to-lung ratio (HLR) was used as a measure of relative MAA uptake, with an HLR of 1.55 discriminating normal from abnormal studies. Of the 247 antimyosin studies, 149 coincided with absent, 38 with mild, and 60 with moderate rejection at biopsy. HLR was 1.68 +/- 0.27, 1.79 +/- 0.22, and 1.91 +/- 0.33 in the three biopsy groups, respectively (p less than 0.0001). Two hundred thirty-eight of 247 antimyosin studies coexisted with absent rejection-related complications; in nine of 247 patients, such complications were detected (five congestive heart failure episodes due to rejection and four episodes of vascular occlusion, which resulted in five deaths), and mean HLR was 1.74 +/- 0.3 and 2.1 +/- 0.16 in the two groups, respectively (p less than 0.0001). No complications were noted in 193 studies of patients with HLR of less than 2.00, whereas in nine of 45 with HRL of 2.00 or greater, complications occurred (p less than 0.0001). None of the 23 patients prospectively followed since surgery who had a gradual decrease in MAA uptake during the first 3 months showed rejection-related complications, whereas persistent uptake was associated with complications in five of nine patients (p less than 0.001). CONCLUSIONS. No rejection-related complications are seen coinciding with HLR of less than 2.00, whereas patients who have complications have an HLR of more than 2.00. The early 3-month pattern of decreasing MAA uptake is associated with a clinical course free of rejection-related complications, whereas a persistent pattern is a signal of the possibility of such complications.  相似文献   
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Non-tuberculous mycobacteria in cystic fibrosis   总被引:2,自引:0,他引:2       下载免费PDF全文
J Torrens  P Dawkins  S Conway    E Moya 《Thorax》1998,53(3):182-185
BACKGROUND—The clinical significance of thepresence of non-tuberculous mycobacteria in the sputum of patients withcystic fibrosis is unclear. A retrospective case-control study wasperformed to assess possible risk factors for non-tuberculousmycobacteria and its impact on clinical status in patients with cystic fibrosis.
METHODS—The records of all patients attending theLeeds cystic fibrosis clinics who were positive for non-tuberculousmycobacteria were examined. Each case was matched with two controls forsex, age, and respiratory function at the time of the firstnon-tuberculous mycobacteria isolate. Details of respiratory function,nutritional status, antibiotic and corticosteroid therapy,Shwachman-Kulczycki (S-K) score, Northern chest radiographic score, andthe frequency of isolation of other bacteria and fungi were collectedfrom two years before to two years after the first non-tuberculousmycobacteria isolate. The patients' genotype and the presence ofdiabetes mellitus were also recorded.
RESULTS—Non-tuberculous mycobacteria were isolatedfrom 14 patients out of a cystic fibrosis population of 372 (prevalence = 3.8%). No significant effect of non-tuberculous mycobacteria wasseen on respiratory function, nutritional status, or S-K score. There was a significant association with the number of intravenous antibiotic courses received before the first isolate with cases receiving, onaverage, twice as many courses as controls (cases 6.64, controls 2.86, 95% CI for difference 1.7 to 5.9). No significant difference was seenbetween cases and controls for Northern scores, previous steroidtherapy, or the incidence of diabetes mellitus.
CONCLUSIONS—Non-tuberculous mycobacteria infectionin patients with cystic fibrosis is uncommon and its clinical impactappears to be minimal over a two year period. Frequent intravenousantibiotic usage is a possible risk factor for colonisation withnon-tuberculous mycobacteria.

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Two types of neutralisation or blocking test using human anti-HBs are described for the confirmation of positive results obtained by immunoradiometric screening for HBSAg.  相似文献   
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