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31.

Background  

Mandatory vaccination has contributed to the success of immunisation programmes but voluntary vaccination allows people to be responsible for their own health. There are benefits from both policies and the arguments between them remain subject to debate within and without the scientific community, both nationally and internationally. The aim of this study is to assess the opinions of those who actually work in the Vaccination Service.  相似文献   
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To study both the pathophysiologic and the prognostic value of ADAMTS13 in thrombotic microangiopathies (TMAs), we enrolled a cohort of 35 adult patients combining a first acute episode of TMA, an undetectable (below 5%) ADAMTS13 activity in plasma, and no clinical background such as sepsis, cancer, HIV, and transplantation. All patients were treated by steroids and plasma exchange, and an 18-month follow-up was scheduled. Remission was obtained in 32 patients (91.4%), and 3 patients died (8.6%) after the first attack. At presentation, ADAMTS13 antigen was decreased in 32 patients (91.4%), an ADAMTS13 inhibitor was detectable in 31 patients (89%), and an anti-ADAMTS13 IgG/IgM/IgA was present in 33 patients (94%). The 3 decedent patients were characterized by the association of several anti-ADAMTS13 Ig isotypes, including very high IgA titers, while mortality was independent of the ADAMTS13 inhibitor titer. In survivors, ADAMTS13 activity in remission increased to levels above 15% in 19 patients (59%) but remained undetectable in 13 patients (41%). Six patients relapsed either once or twice (19%) during the follow-up. High levels of inhibitory anti-ADAMTS13 IgG at presentation were associated with the persistence of an undetectable ADAMTS13 activity in remission, the latter being predictive for relapses within an 18-month delay.  相似文献   
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BACKGROUND: Current research on the continuum of smoking initiation has largely focused on phases of progressing frequency of smoking. To gain more insight into reasons some adolescents do, and others do not, proceed to advanced levels of smoking behavior, a continuum in which two categories of ex-smoking are proposed is examined. METHODS: Standardized scores on psychosocial predictors of smoking among adolescent nonsmoking deciders and quitters were compared cross-sectionally with those of the categories of never smokers, triers, experimenters, and regular smokers (n = 23,317). RESULTS: Never smokers, triers, experimenters, and regular smokers had significantly different characteristics with regard to psychosocial predictors of smoking (P < 0.01), with scores of never smokers indicating that they were least at risk of smoking in the future and those of regular smokers indicating that they were most at risk. Scores of nonsmoking deciders showed that they were less at risk than triers and experimenters and more at risk than never smokers. Quitters seemed to have less risky psychosocial characteristics than experimenters and more risky characteristics than nonsmoking deciders. CONCLUSIONS: Studying transitions of smoking behavior based on six possible phases (i.e., never smoking, nonsmoking deciding, trying, experimenting, regular smoking, and quitting) might lead to more valid insights into predictors of adolescent smoking behavior.  相似文献   
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Among the many effects of family planning is the influence ithas on mortality and morbidity in women and children throughthe mechanism of changing the number and spacing of children.There is a complex set of relationships between mother's age,parity, birth spacing and infant and child mortality and morbidity.Much effort has been put into untangling this web in the hopeof identifying clear causal connections, but for the most parton the basis of inadequate data. Rather than attempt to establishthe relative importance of child spacing as a cause of decreasesin mortality, this paper takes as its starting point that thereis a connection, and presents some possible causal mechanismswhich explain how short birth intervals and child mortalitycould be related. In addition the most frequently cited hypotheses-maternaldepletion and sibling competition-a third is examined-birthcrowding which, it is suggested, influences the pattern of thetransmission of infectious diseases and, in turn, mortality. In the field of maternal mortality, the data which could beused to quantify the benefits of family planning are in evenshorter supply; however, the causal connections are rather moreeasily identified. The final section combines parity-specificdata on maternal mortality with evidence of changes in fertilitypatterns brought about by family planning to assess how successfulwe can hope to be in reducing through birth control the numberof women who die in childbirth.  相似文献   
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In 22 patients with malignancies, treated with high-dose chemoradiotherapy and autologous bone marrow transplantation (BMT), peripheral blood T cell subsets and functions were studied. In ten cytomegalovirus (CMV)-negative patients, CD4+ and CD8+ T cells (representing T cells of the helper/inducer phenotype and T cells of the suppressor/cytotoxic phenotype, respectively), recovered slowly and simultaneously. In 12 CMV-positive patients, however, CD8+ T cells recovered more rapidly than CD4+ T cells and rose to increased counts. No T cells with an immature phenotype (CD1+, OKT6+) were observed. Lymphocyte stimulation by herpes simplex virus infected fibroblasts (and by CMV-infected fibroblasts in CMV-positive patients) in contrast remained high and even increased after BMT in both groups. These data indicate that T cell recovery after autologous BMT is mainly due to proliferation of mature T cells present in the BM graft and not to generation of new T cells from T cell precursors.  相似文献   
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Baldwin  GC; Golde  DW; Widhopf  GF; Economou  J; Gasson  JC 《Blood》1991,78(3):609-615
Hematopoietic growth factor receptors are present on cells of normal nonhematopoietic tissues such as endothelium and placenta. We previously demonstrated functional human granulocyte-macrophage colony- stimulating factor (GM-CSF) receptors on small cell carcinoma of the lung cell lines, and others have reported that certain solid tumor cell lines respond to GM-CSF in clonogenic assays. In the current study, we examine human melanoma cell lines and fresh specimens of melanoma to determine whether they have functional GM-CSF receptors. Scatchard analyses of 125I-GM-CSF equilibrium binding to melanoma cell lines showed a mean of 542 +/- 67 sites per cell with a kd of 0.72 +/- 0.14 nmol/L. Cross-linking studies in the melanoma cell line, M14, showed a major GM-CSF receptor species of 84,000 daltons. Under the conditions tested, the M14 cells did not have a proliferative response to GM-CSF in vitro, nor was any induction of primary response genes detected by Northern analysis in response to GM-CSF. Studies to determine internal translocation of the receptor-ligand complex indicated less than 10% of the 125I-GM-CSF internalized was specifically bound to receptors. Primary melanoma cells from five surgical specimens had GM-CSF receptors; Scatchard analysis was performed on one sample, showing 555 sites/cell with a kd of 0.23 nmol/L. These results indicate that human tumor cells may express a low-affinity GM-CSF receptor protein that localizes to the cell surface and binds ligand, but lacks functional components or accessory factors needed to transduce a signal.  相似文献   
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