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排序方式: 共有782条查询结果,搜索用时 17 毫秒
41.
Gent JF Ren P Belanger K Triche E Bracken MB Holford TR Leaderer BP 《Environmental health perspectives》2002,110(12):A781-A786
We assessed prospectively the risk of increased incidence of respiratory symptoms after exposure to particular fungal genera in a susceptible population--namely, infants (n = 880) at high risk for developing asthma. Days of wheeze or persistent cough, information on maternal allergy and asthma, socioeconomic variables, and housing characteristics were collected over the course of the infant's first year of life. Exposure to mold was assessed by airborne samples collected at one time early in the infant's life. Fungi were identified to genus level, recorded as colony-forming units per cubic meter (CFU/m3), and then categorized into four levels: 0 (undetectable), 1-499 CFU/m3 (low), 500-999 CFU/m3 (medium), and greater than or equal to 1,000 CFU/m3 (high). Effects of mold on wheeze and persistent cough, adjusting for potential confounding factors, were examined with Poisson regression analyses. The two most commonly found genera were Cladosporium (in 62% of the homes) and Penicillium (41%). Cladosporium was associated with reported mold (p < 0.02) and water leaks (p < 0.003). Rate of persistent cough was associated with reported mold [Rate ratio (RR) = 1.49; 95% CI, 1.18-1.88]. The highest level of Penicillium was associated with higher rates of wheeze (RR = 2.15; 95% CI, 1.34-3.46) and persistent cough (RR = 2.06; 95% CI, 1.31-3.24) in models controlling for maternal history of asthma and allergy, socioeconomic status, season of mold sample, and certain housing characteristics. We conclude that infants in this high-risk group who are exposed to high levels of Penicillium are at significant risk for wheeze and persistent cough. 相似文献
42.
Sharon-Lise T. Normand Albert J. Belanger Susan V. Eisen 《Health services & outcomes research methodology》2006,6(1-2):1-19
In measuring outcomes of health care, information is obtained from subjects employing instruments that often use Likert scales. These instruments are typically designed using classical testing theory which assumes the errors around the true scores are normally distributed and constant. Advances in psychometric practices through the use of item response theory (IRT) models have led to more flexibility in scale development and in data analyses. In this paper, we introduce statisticians and health services researchers to IRT models through a case-study of data collected to measure subjective distress. The data consist of self-reports of symptom and problem difficulty obtained from a sample of 2,656 patients discharged with a psychiatric disorder from 13 hospitals in the United States between May 2001 and April 2002. Dimensionality of the trait is assessed using principal factor analysis. Model assessment is made using χ2 statistics and residual analyses. We select items for the scale using the Fisher Information available at selected levels of the underlying trait. 相似文献
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44.
F Lefrère A Delmer F Suzan V Levy C Belanger M Djabarri B Arnulf G Damaj N Maillard V Ribrag M Janvier C Sebban R-O Casasnovas R Bouabdallah F Dreyfus V Verkarre E Delabesse F Valensi E McIntyre N Brousse B Varet O Hermine 《Leukemia》2002,16(4):587-593
Mantle cell lymphoma (MCL) is a distinct clinico-pathological entity with a poor prognosis. We have conducted a prospective study in patients with MCL to evaluate a therapeutic strategy in which CHOP polychemotherapy was followed by DHAP if CHOP failed to induce complete remission. Responding patients then proceeded to an intensification therapy with autologous peripheral blood stem cell transplantation (APBSCT). Twenty-eight consecutive patients with newly diagnosed aggressive MCL were included. After four cycles of CHOP regimen, two complete responses (CR) were obtained (7%) and 14 (50%), five (18%) and seven (25%) patients achieved partial (PR), minor (MR) and no response, respectively (one patient died from septic complications during CHOP induction). The two patients in CR after CHOP underwent intensification with TBI, high-dose cyclophosphamide-etoposide and APBSCT. The other twenty-five patients received DHAP and in this group a response rate of 92% (21 CR (84%), two PR (8%)) was observed. Two patients had progressive disease. The twenty-three responding patients received high-dose therapy (TAM8 regimen: TBI-cytarabine-melphalan) followed by APBSCT. One of the two partial responding patients achieved CR after TAM8. After a median follow-up of 47.6 months (range, 14-70), seven patients have relapsed. Our data confirm that: (1) CHOP regimen induces a low CR rate in MCL; (2) CHOP plus DHAP appears to be much more efficient and allows a large proportion of patients to proceed to high-dose therapy in CR; (3) consolidation therapy including TBI and high-dose Arac-C followed by APBSCT may improve event-free survival. 相似文献
45.
S. Z. Gertler D. MacDonald M. Goodyear P. Forsyth D. J. Stewart K. Belanger J. Perry D. Fulton W. Steward N. Wainman L. Seymour 《Annals of oncology》2000,11(3):315-318
Purpose:We conducted a phase II multicentre study of gemcitabinein patients with anaplastic astrocytoma and glioblastoma multiforme at firstrelapse.
Patients and methods:Patients with anaplastic astrocytoma orglioblastoma multiforme receiving a stable dose of steroids and ECOGperformance status 3 were eligible for this study at the time of firstrelapse. One adjuvant chemotherapy regimen was permissible. Patients receivedgemcitabine 1000 mg/m2 i.v. weekly × 3, repeated on afour-weekly cycle.
Results:Of 20 patients enrolled, 15 were evaluable for response,19 for non-hematological toxicity and 18 for hematological toxicity. Sevenpatients had anaplastic astrocytoma (AA) and twelve glioblastoma multiforme(GBM). Age ranged from 28–71 years (median 50). Fifteen patientsdiscontinued therapy due to disease progression. The median number of cyclesadministered was 1 (range 1–11); only two patients received more thanthree cycles. Hematologic toxicity was acceptable and no grade 4 toxicity wasseen. One patient developed Pneumocystispneumonia and eventualpulmonary embolism; one died of gastric hemorrhage related to steroid therapy.No objective responses were seen. Nine patients had stable disease (medianduration 2.7 months, range 0.9–11.2).
Conclusions:Gemcitabine given in this dose and schedule seemswell tolerated but is not active in patients with recurrent high-gradegliomas. 相似文献
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47.
Belanger SE Bowling JW Leblanc EM Price BB Herzog RR Bozso E 《Ecotoxicology and environmental safety》2005,62(1):75-92
High-solubility alkyl sulfate (HSAS) is a new anionic surfactant for use in consumer product applications that provides enhanced water solubility and improved water hardness tolerance. A comprehensive model stream ecosystem investigation was conducted to assess ecological and toxicological effects of HSAS on stream invertebrates. Model streams were dosed with HSAS for a period of 56 days following 56 days of colonization in a single-pass, flow-through system. Exposures were control and 9.1, 24.1, 64.0, 165.8, and 426.5 microg/L based on specific analytical detection methods. Benthic abundance on gravel substrates, drift, and insect emergence were assessed. Several taxonomically unrelated taxa were found sensitive to HSAS and formed the basis of toxicological conclusions. Abundance or biomass of a limpet (Ferrissea), a bivalve (Corbicula), flatworms (Turbellaria), and a mayfly (Stenonema) was reduced at concentrations ranging from 165.8 to 426.5 microg/L. Principal response curve analysis, a constrained form of principal components analysis, demonstrated consistency with univariate analyses and identified similar populations as being sensitive to HSAS. Comparison with historical studies from the same testing site, streams, and experimental design, but with structurally related alkyl sulfate and alkyl ethoxysulfate anionic surfactants, revealed several similar trends in response profiles at the population level for both tolerant and sensitive species. Based on the comprehensive nature of the study, strength of data trends, and demonstrated sensitivity of the aquatic communities contained in the experimental system, the no-observed-effect concentration for HSAS was concluded to be 64.0 microg/L. An application factor of 1 is justified for deriving a predicted no-effect concentration) for HSAS in aquatic systems. 相似文献
48.
Triche EW Belanger K Bracken MB Beckett WS Holford TR Gent JF McSharry JE Leaderer BP 《Epidemiology (Cambridge, Mass.)》2005,16(3):377-384
BACKGROUND: Secondary heating appliances are important indoor sources of air pollution, including particulate matter, nitrogen dioxide (NO2), and sulfur dioxide (SO2). We hypothesized that the use of secondary heating sources increases respiratory symptoms in women living in nonsmoking households and specifically that concentrations of SO2 and NO2 emitted from heating sources are associated with respiratory symptoms. METHODS: Mothers who delivered babies at 12 hospitals in Connecticut and Virginia (1993-1996) were enrolled. There were 888 women who contributed symptom and exposure information during the winter heating season (15 October to 15 April), for a total of 9783 reporting periods (median = 12 reporting periods per woman, interquartile range 11-12). Adjusted rate ratios (RRs) of effects of source use and measured concentrations on rate of days with symptoms were obtained using generalized estimating equations for a log-linear Poisson model, controlling age, education, race, history of allergies, number of children, dwelling type, and residence state. RESULTS: In adjusted models, each hour-per-day increase in kerosene heater use is associated with an increase in wheezing (RR = 1.06; 95% confidence interval (CI) = 1.01-1.11). Each hour of fireplace use is associated with increased cough (1.05; 1.01-1.09), sore throat (1.04; 1.00-1.08), and marginally with chest tightness (1.05; 0.99-1.12). Each 10 ppb increase in SO2 (a proxy for sulfate aerosol) is associated with increased wheezing (1.57; 1.10-2.26) and chest tightness (1.32; 1.01-1.71). CONCLUSIONS: Emissions from fireplaces, gas space heaters, and kerosene heaters may contribute to respiratory symptoms in a population of nonsmoking women. 相似文献
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50.