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Protein-calorie malnutrition (PCM) adversely affects more or less all immune competent cells. Nonspecific immunity is impaired, particularly adherence and chemotaxis of phagocytes, although the responsiveness of circulating cells may not be the same as that of noncirculating cells. PCM results in numerical and functional impairment in lymphocytes. PCM markedly affects IgG class antibodies which have the highest affinity when directed against T-dependent antigens. These impairments are interrelated, since cooperation between T-helper cell and B-cells is depressed, and the antigen presentation to T-helper cells by macrophages is deficient.  相似文献   
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A survey of silicosis patients and people exposed to silica dust was set up in an effort to look for any relationship between humoral and cell-mediated autoimmune phenomena. It was found that in both sets of subjects, the level of Fc IgG receptor-bearing T lymphocytes was significantly reduced, there was also an inverse correlation between these cell concentrations and IgG- and IgM-circulating immune complex levels. In addition, raised levels of various autoantibodies were found in both groups, however, none of the exposed subjects has developed silicosis to date.  相似文献   
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Fifty-six human immunodeficiency virus-1-positive asymptomatic carriers were tested for the presence of a variety of nonorgan-specific autoantibodies. Antinuclear antibodies were detected in 34 sera, of which 27 were directed to the mitotic spindle apparatus and all were of the IgG isotype. Anti-Golgi complex, anti-centriole, and anti-vimentin antibodies were also present in 20.4, and 4 sera, respectively. Ten patients had less than 500 CD4-carrying T lymphocytes per cubic millimeter. Nine of them had more than one autoantibody. No correlation could be demonstrated between the number of autoantibodies and the level of serum immunoglobulins.  相似文献   
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抗CCT2单克隆抗体博来霉素A6偶联物可吸附胶体金颗粒(McAb-A6-Au)。电镜观察表明,在4℃,1h,表面有McAb-A6-Au颗粒的CEM细胞最高达78%;在37℃,4h,内化McAb-A6-Au颗粒的CEM细胞高达72%。而抗原性无关的U937细胞仅为14%。并且McAb-A6-Au颗粒能直接穿过细胞膜、核膜进入细胞浆和细胞核。37℃,1h已有10~18%的CEM细胞核内有McAb-A 6-Au颗粒。实验结果提示了单抗与博来霉素A6的偶联物与选择性地结合靶细胞,而且进入细胞速度快、穿透力强,有可能成为治疗白血病药物。  相似文献   
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OBJECTIVE: To document the prevalence of rheumatoid arthritis (RA) and spondyloarthropathy (SpA) in Brittany, France. METHODS: (1) Members of rheumatism self-help groups screened cases using questionnaires. (2) Rheumatologists in our unit contacted persons who had possible inflammatory rheumatic diseases and persons who refused the first interview. (3) When diagnosis remained unknown or discordant with the questionnaire, the general practitioner or the rheumatologist of these patients was interviewed. (4) Patients without diagnosis and who had not had a rheumatological examination were examined without charge by a rheumatologist. RESULTS: An overall prevalence rate of 0.62% (0.33-0.91) and 0.47% (0.22-0.72) was found for RA and for SpA, respectively. The prevalence of RA and SpA was 0.86 (0.39-1.33) and 0.53 (0.16-0.9) in women and 0.32 (0.01-0.63) and 0.41 (0.05-0.77) in men. The minimum prevalence of RA and SpA calculated on the estimated initial group (3189 persons) was 0.53 (0.28-0.78) and 0.41 (0.18-0.63), respectively. CONCLUSION: Our telephone survey revealed that the prevalences of RA and SpA are nearly similar among our population and that SpA is as common in women as in men.  相似文献   
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Polymorphonuclear leukocyte functions were studied in 92 patients with protein-calorie malnutrition. Serum folic acid levels were higher than 3 ng/ml in 38 patients and 3 ng/ml or less in 54 patients. Significant differences were found between these two groups of patients with regard to phagocytosis (81.5 +/- 1.9 versus 69.2 +/- 2.0 percent, p less than 0.001) and bactericidal ability (90.6 +/- 1.1 versus 84.5 +/- 2.3 percent, p less than 0.05). Correction of folic acid deficiency in 22 patients was associated with recovery of normal phagocytosis (p less than 0.001) but not bactericidal function. Adding folic acid to the serum of eight patients also restored normal phagocytic function (p less than 0.001). A correlation was found in vivo and in vitro between changes over time in folic acid levels and in phagocytosis.  相似文献   
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ObjectiveThis meta-evaluation aimed to summarize all available evidence regarding different fissure sealants on occlusal caries prevention, arrest, retention rate, adverse effect, and cost-effectiveness; when compared with no intervention, other preventive or minimally-invasive procedures.Materials and MethodsThe systematic reviews and meta-analyses were identified via four electronic databases and manual searching. Two independent reviewers performed study selection, data extraction, quality assessment with AMSTAR-2.ResultsAmong the 366 records yielded, 38 systematic reviews were identified as eligible 24 of them included meta-analyses. Moderate evidence has supported the efficacies of resin-based sealants (RBS) in occlusal caries prevention, arrest and cost-effectiveness compared to no interventions. Low to very low certainty of evidence suggested similar effectiveness of glass-ionomer cements in caries prevention with RBS and more superior performance of resin infiltration in arresting non-cavitated occlusal lesions.ConclusionThis meta-evaluation supports the use of RBS on permanent molars to reduce occlusal caries occurrence, arrest lesion progression and alleviate oral health inequalities between individuals of different socioeconomic status. This meta-evaluation also advocates further research on glass-ionomer cements and resin infiltration with respect to their efficacies in caries prevention and arrest.  相似文献   
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