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51.
Background
The aim was to examine the numbers of hours worked and patient visits provided by age and gender of dentists in Australia, and compare with previous estimates to describe trends.Methods
Data were collected from a random sample (N = 2961) of Australian dentists. Private sector dentists working in clinical practise were included in the analysis.Results
The response rate was 49% (N = 1345 dentists). Hours per year worked and number of patient visits per year were lower for dentists aged 65 years and older compared with younger dentists, and were higher for male compared with female dentists aged 35–45 to 55–64 years. Hours per year worked were lower in 2013–2014 than reported in 2009–2010, but the number of patient visits in 2013–2014 was similar to the previously reported estimate from 2009–2010.Conclusions
Hours worked and visits provided were only lower among older dentists aged 65 years or more. Male dentists tend to work more hours per year and provide more patient visits per year than female dentists. Over the last decade, Australian dentists maintained a stable output of visits per year despite a trend towards fewer hours worked per year. 相似文献52.
53.
Private health insurance plays a key role in financing dental care in Australia. Having private dental insurance has been associated with higher levels of access to dental care, visiting for a check‐up and receiving a favourable pattern of services. Associations with better oral health have also been reported. In the absence of any existing review, this paper aims to systematically review the relationship between dental insurance and dental service use and/or oral health outcomes in Australia. A systematic search of online databases and subsequent sifting resulted in 36 publications, 33 of which were cross sectional and three cohort analyses. Dental service outcomes were more commonly reported than oral health outcomes. There was considerable heterogeneity in the outcome measures reported, for both service use and health outcomes. Overall, the majority of the evidence was from cross sectional studies and few studies reported analyses adjusted for confounding factors. The consolidated evidence points towards a positive association between dental insurance and dental visiting. Dentally insured adults are likely to have more regular access to dental care and have a more favourable pattern of service use than the uninsured. However, evidence of associations between dental insurance and oral health are mixed. 相似文献
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Full-length but not truncated CD34 inhibits hematopoietic cell differentiation of M1 cells 总被引:8,自引:1,他引:8
CD34 is expressed on human and murine hematopoietic stem and progenitor cells and its clinical usefulness for isolation of stem/progenitor cells has been well established. Although expression of CD34 is regulated in a developmental stage-specific manner, the function of CD34 is not known. Recently we have shown that both a full-length and truncated form of CD34 protein is expressed by hematopoietic cells (Blood 84:691, 1994). To test whether failure to suppress either form of CD34 could affect terminal myeloid differentiation, we constitutively expressed these CD34 proteins in murine M1 myeloid leukemia cells, which can be terminally differentiated to macrophages by treatment with interleukin-6 of leukemia inhibitory factor. Surprisingly our results show that forced expression of the full-length but not the truncated form of CD34 impedes terminal differentiation by these agents. Because the difference between the two forms of CD34 protein resides in the length of their respective cytoplasmic tail domains, our findings strongly suggest that the cytoplasmic domain region of full-length CD34 is responsible for the observed maturation arrest phenotype. These findings suggest a potential negative regulatory role for full-length CD34 in hematopoietic cell differentiation and may explain, at least in part, the block in maturation observed in CD34+ acute myeloid leukemia. 相似文献
58.
We have previously reported the isolation of a monoclonal antibody (NHL- 30.5) that reacts with an antigen expressed on a substantial proportion of marrow and blood cells of most patients with newly diagnosed or relapsing acute myeloid leukemia. This antigen is also found on several cell lines derived from myeloid malignancies of human origin. It is not present on mature hemopoietic cells or on the majority of differentiating bone marrow cells. In order to determine whether the NHL-30.5 antigen may, nevertheless, be expressed on low-frequency primitive normal hemopoietic cells, not detected in standard antibody screening procedures, its expression was studied on clonogenic erythropoietic and granulopoietic cells. Light-density (less than 1.077 g/mL) suspensions of normal or chronic myelogenous leukemia bone marrow and peripheral blood cells were stained with NHL-30.5 and fluorescein isothiocyanate labeled second antibody and then sorted into two fractions using the fluorescence-activated cell sorter. The first contained the top 5% of cells with the highest fluorescence intensity. The remainder were collected in the second fraction. Colony assays of both fractions showed the first to be enriched in CFU-E, BFU-E, and CFU- C content (fourfold to 17-fold). The second fraction was correspondingly depleted of these progenitors. These findings reveal NHL-30.5 antigen expression to be a transient event during normal hemopoiesis that characterizes primitive hemopoietic cells on several pathways. Subsequent experiments showed that the presence of up to 10 micrograms/mL of purified NHL-30.5 antibody in colony assay cultures neither inhibited nor stimulated colony formation. Marrow fibroblasts (subcultured marrow adherent cells) were NHL-30.5 negative. Immunoprecipitation studies showed that the antigen detected by NHL- 30.5 is clearly distinct from that identified by My-10, another monoclonal antibody that has previously shown some similarities to NHL- 30.5. It thus appears that the NHL-30.5 antibody reacts with a new myeloid differentiation antigen of as yet unidentified function that is normally restricted in its expression to early stages of hemopoiesis. 相似文献
59.
In earlier studies we have shown that a final concentration of 0.69% glycerol in blood mixed with an experimental additive solution, EAS 25, improves the in vitro quality and in vivo survival of red blood cells (RBCs). The objective of this study was to determine if the better preservation of RBCs in EAS 25 is correlated with the improved maintenance of membrane lipids and proteins and decreased vesiculation. Split units of RBCs were stored in Adsol or EAS 25 (mmol/L: adenine 2/2, dextrose 122/110, mannitol 42/55, glycerol 0/150, NaCl 154/50). After 12 weeks storage, RBC and microvesicle membranes were analyzed for cholesterol, phospholipid, diphenyl hexatriene fluorescence anisotropy, and acetylcholinesterase (AchE) activity. Bands 3 and 4.1 were identified in the microvesicle membranes by immunoblotting. The RBC membrane cholesterol, phospholipids, and AchE remained higher in EAS 25 than in Adsol (P < .001). Vesicle membrane lipids and AchE in EAS 25 were significantly less than in Adsol (P < .001). The fluidity of stored cells in both the solutions was greater than the prestorage samples. Immunoblotting analyses showed that bands 3 and 4.1 were greatly reduced in the microvesicle membranes shed by the RBCs stored in EAS 25 compared with those formed in Adsol. 相似文献
60.
The inappropriate expression of c-myc in cells deprived of growth factors has recently been implicated in the activation of programmed cell death (apoptosis). The studies described here examine the ability of interleukin-3 (IL-3) or erythropoietin (Epo) to suppress apoptosis that occurs in association with enforced myc expression during cell cycle arrest of a murine IL-3-dependent myeloid progenitor cell line, 32D. G1 arrest was observed when culturing 32D cells to high density in medium supplemented with IL-3, or at subconfluent densities in medium supplemented with Epo. Under both conditions, endogenous c-myc expression was downregulated and viability was maintained. In clones of cells in which c-myc is constitutively expressed from a retroviral vector, enforced c-myc expression was associated with the activation of apoptosis at high cell densities. Similarly, enforced c-myc expression was deleterious to cell survival when these cells were cultured in Epo, as apoptosis was evident within 6 hours. The results support the concept that inappropriate c-myc expression activates apoptosis and that neither IL-3 nor Epo can suppress this program under these conditions. 相似文献