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ObjectiveTo investigate disparities in full immunization coverage across and within 86 low- and middle-income countries.MethodsIn May 2015, using data from the most recent Demographic and Health Surveys and Multiple Indicator Cluster Surveys, we investigated inequalities in full immunization coverage – i.e. one dose of bacille Calmette-Guérin vaccine, one dose of measles vaccine, three doses of vaccine against diphtheria, pertussis and tetanus and three doses of polio vaccine – in 86 low- or middle-income countries. We then investigated temporal trends in the level and inequality of such coverage in eight of the countries.FindingsIn each of the World Health Organization’s regions, it appeared that about 56–69% of eligible children in the low- and middle-income countries had received full immunization. However, within each region, the mean recorded level of such coverage varied greatly. In the African Region, for example, it varied from 11.4% in Chad to 90.3% in Rwanda. We detected pro-rich inequality in such coverage in 45 of the 83 countries for which the relevant data were available and pro-urban inequality in 35 of the 86 study countries. Among the countries in which we investigated coverage trends, Madagascar and Mozambique appeared to have made the greatest progress in improving levels of full immunization coverage over the last two decades, particularly among the poorest quintiles of their populations.ConclusionMost low- and middle-income countries are affected by pro-rich and pro-urban inequalities in full immunization coverage that are not apparent when only national mean values of such coverage are reported.  相似文献   
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Objectives

The aim of this study was to determine the prevalence of apical periodontitis (AP) detected in cone beam CT (CBCT) images from a database.

Methods

CBCT images of 300 Brazilian patients were assessed. AP images were measured in three dimensions. Age, gender, number and location of total teeth in each patient were considered. AP location was considered according to tooth groups. The extent of AP was determined by the largest diameter in any of the three dimensions. Percentages and the χ2 test were used for statistical analysis.

Results

AP was found in 51.4% of the patients and in 3.4% of the teeth. Higher prevalence of AP was found in 60- to 69-year-olds (73.1%) and in mandibular molars (5.9%) (p < 0.05). Inadequate endodontic treatment presented higher prevalence of AP (78.1%).

Conclusions

AP can be frequently found in CBCT examinations. The presence of AP has a significant association with patients'' age, and tooth type and condition. CBCT databases are useful for cross-sectional studies about AP prevalence in a population.  相似文献   
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肝病细胞疗法的系统观   总被引:3,自引:0,他引:3  
  相似文献   
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Budel  LM; Touw  IP; Delwel  R; Lowenberg  B 《Blood》1989,74(8):2668-2673
The binding of granulocyte colony-stimulating factor (G-CSF) to normal and human acute myeloid leukemia (AML) cells was investigated with radiolabeled recombinant human G-CSF (rhG-CSF). In all 14 cases of primary AML specific receptors for G-CSF were demonstrated on purified blast cells. The average numbers of G-CSF receptors ranged from very low to 428 receptors per cell (mean). Normal granulocytes showed G-CSF binding sites on their surface at higher densities (703 to 1,296 sites per cell). G-CSF receptors appeared to be of a single affinity type with a dissociation constant (kd) ranging between 214 and 378 pmol/L for AML blasts and 405 to 648 pmol/L for granulocytes. In 12 of 14 cases, including those with relatively low specific binding, G-CSF was a potent inducer of DNA synthesis of blasts in vitro; therefore, apparently relatively few receptors are required to permit activation of AML cell growth. However, in two cases cell cycling was not activated in response to G-CSF despite G-CSF receptor availability. The results show that G-CSF receptors of high affinity are frequently expressed on the blasts of human AML, but their presence may not be a strict indicator of the proliferative responsiveness of the cells to G- CSF.  相似文献   
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Webb  LM; Feldmann  M 《Blood》1995,86(9):3479-3486
CD28 is a major costimulatory signal receptor for T cells. We have used human naive CD4+ cells from cord blood to analyze the effect of the CD28/B7 costimulatory pathway on development of T helper (Th) subsets. We show that CD28 costimulation is critical for development of the Th2 cytokine-producing cells and that in the absence of CD28 costimulation, cells are not primed to produce Th2 cytokines and consequently "default" to the Th1 subset, independent of the presence of exogenous cytokines. After CD28 costimulation, cells differentiate into a subset that produces Th2 cytokines. However, further CD28 costimulation is not required to maintain Th2 cytokine production. We conclude that D28 costimulation is critical for the development of Th0 and Th2 subsets, but not for the maintenance of cytokine production.  相似文献   
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