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Researchers usually employ orthogonal arrays or D-optimal designs with little or no attribute overlap in stated-choice surveys. The challenge is to balance statistical efficiency and respondent burden to minimize the overall error in the survey responses. This study examined whether simplifying the choice task, by using a design with more overlap, provides advantages over standard minimum-overlap methods. We administered two designs for eliciting HIV test preferences to split samples. Surveys were undertaken at four HIV testing locations in San Francisco, California. Personal characteristics had different effects on willingness to pay for the two treatments, and gains in statistical efficiency in the minimal-overlap version more than compensated for possible imprecision from increased measurement error. 相似文献
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Casonis skin test and indirect haemagglutination test (IHA) are still used in Turkey. The preoperative IHA test or Casonis skin test results of 120 patients with surgically confirmed hydatidosis were retrospectively studied during 1997–2004. At the same period, 306 patients with non-hydatid disease had serologic results for echinococcosis. The sensitivity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 70, 62, and 56%, respectively. Casonis skin test components had higher sensitivity than IHA (P<0.01). The specificity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 87, 85, and 84%, respectively. Cystic lesions in non-hydatid patients were localised commonly in the lungs. The occurrence of hydatid disease for pulmonary, hepatic, and renal cysts was 19, 54, and 5%, respectively. An immediate skin reaction to crude hydatid antigens is more useful than IHA. 相似文献
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Deniz Eyice Karabacak Semra Demir Osman Ozan Yeğit Ali Can Kadriye Terzioğlu Derya Ünal Müge Olgaç Raif Coşkun Bahauddin Çolakoğlu Suna Büyüköztürk Aslı Gelincik 《Allergy》2021,76(8):2535-2543
Background
Hereditary angioedema (HAE) attacks can be provoked with psychological factors. The aim of this study was to assess the effects of anxiety, depression and stress related to COVID-19 pandemic on disease activity of HAE patients during the quarantine period (QP) and the return to normal period (RTNP).Methods
This study was conducted between March 2020 and September 2020 in four allergy centres. Demographic, clinical features and mental health status were evaluated in QP (from March to the beginning of June) and RTNP (from June to the beginning of September) applied by the government. The 10-point visual analogue scale (VAS10) was used to define the severity of HAE attacks. Depression, Anxiety and Stress Scales-21 (DASS-21) and Fear of COVID-19 (FC-19) scale were performed to assess mental health status.Results
139 HAE patients were included in the study. In QP, median attack numbers and median VAS10 scores were 5 (min-max: 0–45) and 6 (min-max: 0–10), respectively. HAE attack numbers, DASS-21 stress, anxiety, depression and total DASS-21 scores, and FC-19 scores were higher in QP than RTNP (p = 0.001, p < 0.001, p = 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). However, there was no difference in attack severity scores between the two periods (p > 0.05).Conclusions
This study revealed that the restriction measures during COVID-19 outbreak cause an increase in the number of HAE attacks in relation to anxiety, depression, stress and fear of COVID-19 pandemic. Therefore, it is important to provide psychological support to HAE patients during the pandemic.7.
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Onder I Topcu S Dökmetas HS Türkay C Seyfikli Z 《Materia medica Polona. Polish journal of medicine and pharmacy》1997,29(1-4):11-13
In this study the effect of hypoxia on thrombocytes was investigated in patients with a chronic obstructive pulmonary disease (COPD). 15 Hypoxic (group 1), 15 nonhypoxic (group 2) patients with COPD and 10 healthy persons (group 3) were included in the study. The differences in haemoglobin, hematocrit and PaCO2 values of group 1 and group 2 were insignificant, but there was a significant difference between group 3 and the other two groups. The differences in blood pH values in the above groups were insignificant, but the differences in FEV1, FVC and PaO2 values were significant. We found that thrombocyte aggregation increased significantly in group 1 and group 2. Also the platelet count decreased and mean platelet volume increased significantly in group 1. As a result, we think that in hypoxic patients with COPD, thrombocyte count decreases, volume and aggregation formation increases and oxygen plus antiaggregation therapy may have positive effects on the survival and life quality of these patients. 相似文献
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Merget R Topcu M Friese K Vormberg R Fuchs T Raulf-Heimsoth M Breitstadt R 《International archives of occupational and environmental health》1999,72(8):533-538
Objectives: To assess the health effects of hexamethylenetetramine (HMT) on the airways and the skin of workers in the chemical industry.
Methods: A cross-sectional study was performed with 17 employees of a HMT-producing chemical plant and 16 control subjects from the
plant. In addition, we examined 4 out of 5 subjects who had left the production for medical reasons during the last 10 years.
Anamnestic data, total and specific IgE to four environmental allergens, lung function and bronchial responsiveness to methacholine
were assessed by standard procedures. Skin prick tests (SPT) and patch tests were performed with known sensitizing substances
and HMT 100 mg/ml and 2% pet and aq. Results: A high number of exposed subjects and controls reported symptoms during the previous year (64.7% vs 68.8%), most of them
were not related to work. Work-related symptoms and objective parameters did not show differences between groups. No sensitizations
to HMT as assessed by SPT or patch tests were found. Among those who had left the HMT production for medical reasons, 2 former
baggers showed sensitizations to HMT by patch tests. These reported eczema during exposure but lost symptoms after removal
from exposure. Geometric mean HMT concentrations as assessed by personal sampling were 0.3 [95% confidence intervals (CI)
0.1; 0.9] mg/m3 in shiftleaders and 0.6 (95% CI 0.3; 1.1) mg/m3 in baggers. Conclusion: High exposures to HMT may cause allergic contact dermatitis. There was no evidence of an increased risk for occupational
asthma at mean airborne HMT concentrations below 1 mg/m3.
Received: 4 February 1999 / Accepted: 10 July 1999 相似文献
10.
Substandard application of preimplantation genetic screening may interfere with its clinical success
Munné S Gianaroli L Tur-Kaspa I Magli C Sandalinas M Grifo J Cram D Kahraman S Verlinsky Y Simpson JL 《Fertility and sterility》2007,88(4):781-784
The intent of this study was to evaluate a recent randomized clinical trial evaluating the effect of preimplantation genetic screening (PGS) that reports a negative effect on pregnancy outcome. This article reviews appropriate PGS techniques and how they differ from the trial in question. A closer look at the clinical trial in question reveals significant lack of expertise in biopsy, cell fixation, genetic analysis, and patient selection. At most, this trial demonstrates that in inexperienced hands, PGS can be detrimental. No other conclusions concerning the effect of PGS on pregnancy results can be drawn from the trial. 相似文献