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51.
BACKGROUND:
Diagnosing pulmonary tuberculosis (PTB) is challenging in patients who are unable to spontaneously expectorate. Published evidence suggests that induced sputum (IS) is the least invasive and most cost-effective method of diagnosis, and should be used before fibre-optic bronchoscopy (FOB).METHODS:
The medical records of 337 adults treated for PTB in northern Alberta between 1997 and 2007 were reviewed to determine whether local practice patterns reflect the evidence. Microbiological data were collected from the Provincial Laboratory for Public Health. Demographic information was collected from the patients’ charts.RESULTS:
A total of 8.5% (26 of 307) of PTB patients had IS collected, whereas 35.8% (110 of 307) underwent FOB. Among FOB patients, 56.4% (62 of 110) had no sputum sent before the procedure and 29% (18 of 62) of these patients were smear positive. Only five patients referred for FOB had IS sent previously. There were no demographic factors predictive of IS use, whereas being an inpatient at a teaching facility or having a nodule or mass on chest x-ray was predictive of FOB referral. Because so few IS samples were available, not all patients had spontaneously expectorated sputum, IS and FOB tests performed; thus, the calculated yields were not comparable with one another.CONCLUSIONS:
Despite published evidence recommending IS collection before FOB referral in suspected PTB patients, clinicians in our health region appeared to prefer early FOB over IS by a large margin. This practice pattern is less cost effective and exposes patients and health care workers to greater risk. Further research is needed to identify the reasons for the underuse of sputum induction. 相似文献52.
Joseph P. Shivers Linda Mackowiak Henry Anhalt Howard Zisser 《Journal of diabetes science and technology》2013,7(3):789-794
Safe and widespread use of diabetes technology is constrained by alarm fatigue: when someone receives so many alarms that he or she becomes less likely to respond appropriately. Alarm fatigue and related usability issues deserve consideration at every stage of alarm system design, especially as new technologies expand the potential number and complexity of alarms. The guiding principle should be patient wellbeing, while taking into consideration the regulatory and liability issues that sometimes contribute to building excessive alarms. With examples from diabetes devices, we illustrate two complementary frameworks for alarm design: a “patient safety first” perspective and a focus on human factors. We also describe opportunities and challenges that will come with new technologies such as remote monitoring, adaptive alarms, and ever-closer integration of glucose sensing with insulin delivery. 相似文献
53.
目的 用重组日本血吸虫22kD表膜蛋白(rSj22)免疫水牛,检测特异性IgG抗体的应答水平,并观察抗血吸虫的保护效果。方法 用抗原(rSj22)加佐剂(Quil-A)肌肉注射免疫水牛,以1000条日本血吸虫尾蚴攻击感染,感染后55d剖杀,计算减虫和减卵率,用免疫印斑和ELISA方法测定抗体反应。结果 免疫组每头牛血清均能特异地识别Quil-A对照组相比,减虫率仅8.5%肝卵EPG减少12.3%,粪卵EPG减少26.8%,但均无统计学意义,结论 用rSj22kD抗原免疫水牛诱导的特异性IgG抗体不能发挥免疫保护作用。 相似文献
54.
Previous studies have suggested that interleukin-6 (IL-6) may mediate growth of multiple myeloma (MM) in either an autocrine or paracrine growth mechanism. However, those molecules which can trigger IL-6 secretion either by tumor cells or non-MM marrow cells are not well characterized. In the present study, we have examined the expression and functional significance of CD40 on MM and plasma cell leukemia (PCL) cells and derived cell lines, as well as long-term bone marrow stromal cells (BMSCs) and derived cell lines. CD40 was expressed on the majority of MM cells (> 90%) and BMSCs (> 70%). Triggering via CD40 using NIH3T3 CD40 ligand transfectant (CD40LT) cells increased (> 30%) cell surface CD80, CD18, CD11a, CD11b, and CD11c expression on MM cell lines. Culture with either fresh or paraformaldehyde fixed NIH3T3 CD40LT cells upregulates IL-6 secretion in MM cells and MM-derived cell lines, as well as normal and MM bone marrow mononuclear cells (BMMCs), BMSCs, and BMSC lines; this effect can be specifically blocked by anti- CD40 monoclonal antibody (MoAb). BMMCs and BMSCs from patients with MM secreted significantly more IL-6 than those from healthy donors (n = 3, P < .001); moreover, after stimulation using CD40L, IL-6 secretion was fourfold greater (n = 3, P < .001) from MM BMMCs and BMSCs than from normal BMMCs and BMSCs. Myeloma (CD38+CD45RA-) cells and non-MM (CD38+CD45RA+, CD38-CD45RA+, and CD38-CD45RA-) BMMCs were separated by dual fluorescence cell sorting. The latter secreted fourfold more IL-6 than the former (n = 2, P < .001). Increased IL-6 secretion (up to 28- fold) and proliferation (Stimulation index 10) by CD38+CD45RA-MM cells was triggered by culture with NIH3T3 CD40LT cells. Finally, anti- CD40MoAb partially (30%) blocked tumor cell to BMSC adhesion-induced IL- 6 secretion. These studies support the view that CD40L may trigger IL-6 secretion by both MM cells and BMSCs and that IL-6-mediated autocrine and paracrine growth mechanisms may be possible in MM. 相似文献
55.
Mouse strain variability in the expression of the hematopoietic stem cell antigen Ly-6A/E by bone marrow cells 总被引:8,自引:6,他引:8
The cell surface molecule Ly-6A/E provides a convenient marker for primitive stem cells in the hematopoietic tissues of both fetal and adult mice. However, previous studies have shown that Ly-6A/E expression by lymphocytes is variable depending on the haplotype of the Ly-6 locus. Therefore, strain-specific variation in Ly-6A/E expression by bone marrow (BM) cells was investigated. The results show that Ly-6a mice have, on average, 50% of the number of BM cells expressing Ly-6A/E relative to that for Ly-6b mice. Furthermore, among the 5% of BM cells that do not express antigens characteristic of mature T, B, myeloid, or erythroid lineages, which include the primitive hematopoietic stem cell compartment, Ly-6a mice have, on average, more than fivefold fewer Ly- 6A/E+ cells relative to that for Ly-6b mice. Isolation of Ly-6A/E- and Ly-6A/E+ cells from mice of both haplotypes showed that, whereas 99% of the marrow repopulating activity (MRA) of C57BL/Ka (Ly-6b) mice could be recovered in the Ly-6A/E+ fraction, only about 25% of the MRA of BALB/c (Ly-6a) was recoverable in the same population. On a per-cell basis, the Ly-6A/E+ cells that were isolated from BALB/c mice were essentially equivalent in MRA to those isolated from C57BL/Ka mice. Thus, whereas a large percentage of the hematopoietic stem cells of Ly- 6a mice do not express the Ly-6A/E molecule, the antigen may be used to isolate a subset of stem cells from these mice. These results show that hematopoietic stem cell phenotype can vary between mouse strains and imply that caution should be exercised in the identification of human stem cell antigens such as CD34, because a similar variability may occur between individual humans. To further explore the influence of Ly- 6 haplotype on Ly-6A/E expression by specific cell subsets, lymph-node lymphocytes from a panel of mouse strains were analyzed by multiparameter flow cytometry for correlated expression of Ly-6A/E, CD4, and CD8. All Ly-6a strains examined had less than 20% Ly-6A/E+ cells, and those cells were predominantly CD8+ T lymphocytes. In contrast, the Ly-6b strains had greater than 30% Ly-6A/E+ cells, and those cells included CD4+, CD8+, and B lymphocytes. 相似文献
56.
OBJECTIVE: The purpose of this study was to assess the clinical and economic impact of the introduction of inhaled corticosteroid therapy for asthma in a cohort of children 12 years and younger who were North Carolina Medicaid enrollees.
METHODS: The North Carolina Medicaid claims database was used to retrieve clinical and economic variables for the purpose of this study. The case group, which was comprised of 84 children who started corticosteroid inhaler therapy between March 1994 and March 1995, was followed up for 1 year before and 1 year after the start of the therapy. The control group was comprised of 72 children with similar severity of asthma who remained on any other therapy other than corticosteroids for a continuous 2-year period. Paired t-tests were used to compare differences, and multiple regression analysis was used to adjust for potential confounders.
RESULTS: There was a 58% reduction in hospital visits, and a 19% reduction in physician visits in the case group after initiation of inhaled corticosteroids. In the control group, an increase of 34% in the number of outpatient visits occurred in the second year. All the decreases and increases were statistically significant. Children with regular patterns of inhaled corticosteroid refills were found to be significantly lower costing for Medicaid. However, after adjusting for potential confounders, no significant change in health care costs per asthmatic child occurred as a result of the introduction of inhaled corticosteroid therapy.
CONCLUSION: Overall, the study found that introduction of inhaled corticosteroids in a cohort of asthmatic children enrolled in Medicaid was beneficial to Medicaid because it brought about dramatic decreases in health care utilization without additionally increasing costs. 相似文献
METHODS: The North Carolina Medicaid claims database was used to retrieve clinical and economic variables for the purpose of this study. The case group, which was comprised of 84 children who started corticosteroid inhaler therapy between March 1994 and March 1995, was followed up for 1 year before and 1 year after the start of the therapy. The control group was comprised of 72 children with similar severity of asthma who remained on any other therapy other than corticosteroids for a continuous 2-year period. Paired t-tests were used to compare differences, and multiple regression analysis was used to adjust for potential confounders.
RESULTS: There was a 58% reduction in hospital visits, and a 19% reduction in physician visits in the case group after initiation of inhaled corticosteroids. In the control group, an increase of 34% in the number of outpatient visits occurred in the second year. All the decreases and increases were statistically significant. Children with regular patterns of inhaled corticosteroid refills were found to be significantly lower costing for Medicaid. However, after adjusting for potential confounders, no significant change in health care costs per asthmatic child occurred as a result of the introduction of inhaled corticosteroid therapy.
CONCLUSION: Overall, the study found that introduction of inhaled corticosteroids in a cohort of asthmatic children enrolled in Medicaid was beneficial to Medicaid because it brought about dramatic decreases in health care utilization without additionally increasing costs. 相似文献
57.
J B Johnston L G Israels G J Goldenberg C D Anhalt L Verburg M R Mowat A Begleiter 《Journal of the National Cancer Institute》1990,82(9):776-779
Glutathione (GSH) levels and glutathione S-transferase (GST) activities were measured in the leukemia cells of 12 patients with chronic lymphocytic leukemia. Both were correlated with prior clinical exposure to alkylating agents and with DNA cross-link formation by chlorambucil in these cells in vitro. No correlation was observed between prior exposure to alkylating agents and GSH level or GST activity. An inverse correlation was observed between GST activity and cross-linking by chlorambucil, which was enhanced if both GST activity and GSH level were related to cross-linking. These findings suggest that the combination of GST and GSH protects the DNA of leukemia cells from chlorambucil, but the role of this combination in clinical resistance remains to be determined. 相似文献
58.
59.
60.
JH Raphael JL Southall TV Gnanadurai GJ Treharne GD Kitas 《BMC musculoskeletal disorders》2002,3(1):17-8