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61.
RESEARCH QUESTIONS: Couples undergoing IVF in Switzerland may have embryos in excess of their clinical need that they can donate to human embryonic stem cell research. Thus a new practice has emerged in Switzerland when IVF treatment and embryonic stem cell research come into contact. This interface needs to be investigated from an ethical-legal point of view to facilitate a fair informed choice process for the couples involved.METHODS: Ethical analysis, patient perspectives elaboration. Interdisciplinary approach that draws on the research project JESP-ELSI (joint embryonic stem cell research project--ethical legal and societal implications). RESULTS AND CONCLUSIONS: To facilitate the donation of surplus embryos to human embryonic stem cell research, we propose a procedure of informed choice that fits to the current Swiss legal situation. In addition we identify problems within the current legal setting and suggest methods to improve communication at the interface between IVF and embryonic stem cell research from an ethical perspective.  相似文献   
62.
STUDY OBJECTIVES: The noninvasive assessment and monitoring of airway inflammation could be important in respiratory disease. The pH of exhaled breath condensate (EBC) is a promising marker. Although pH has been measured in the EBC of adults with inflammatory airway diseases, no study has measured this in children. DESIGN: This study aimed to assess whether there is a change in pH in the EBC of children with cystic fibrosis (CF) and asthma, and to try to determine whether pH could be used as a marker of airway inflammation. Furthermore, the relationships among EBC pH, severity of disease, and oxidative stress were studied. PATIENTS AND METHODS: We studied 20 children with CF (mean [+/- SEM] age, 7 +/- 3 years), 20 children with asthma (mean age, 7 +/- 2 years), and 15 age-matched healthy children (mean age, 7 +/- 2 years). The pH of EBC was measured using a pH meter. MEASUREMENTS AND RESULTS: Lower pH values were observed in the EBC of children with CF and asthma compared to control subjects (mean pH, 7.23 +/- 0.03 and 7.42 +/- 0.01 vs 7.85 +/- 0.02, respectively). Furthermore, relationships among EBC pH, severity of asthma, and the presence of an infective exacerbation of CF was found. There was a negative correlation between exhaled pH and exhaled leukotriene B(4) concentrations (r = -0.5; p < 0.005). CONCLUSION: We conclude that the measurement of EBC pH may be useful in the evaluation of airway inflammation in children with asthma and CF.  相似文献   
63.

Background

Conflicting evidence exists on whether smoking acts as an effect modifier of the association between APOE genotype and risk of coronary heart disease (CHD).

Methods and results

We searched PubMed and EMBASE to June 11, 2013 for published studies reporting APOE genotype, smoking status and CHD events and added unpublished data from population cohorts. We tested for presence of effect modification by smoking status in the relationship between APOE genotype and risk of CHD using likelihood ratio test.In total 13 studies (including unpublished data from eight cohorts) with 10,134 CHD events in 130,004 individuals of European descent were identified. The odds ratio (OR) for CHD risk from APOE genotype (ε4 carriers versus non-carriers) was 1.06 (95% confidence interval (CI): 1.01, 1.12) and for smoking (present vs. past/never smokers) was OR 2.05 (95%CI: 1.95, 2.14). When the association between APOE genotype and CHD was stratified by smoking status, compared to non-ε4 carriers, ε4 carriers had an OR of 1.11 (95%CI: 1.02, 1.21) in 28,789 present smokers and an OR of 1.04 (95%CI 0.98, 1.10) in 101,215 previous/never smokers, with no evidence of effect modification (P-value for heterogeneity = 0.19). Analysis of pack years in individual participant data of >60,000 with adjustment for cardiovascular traits also failed to identify evidence of effect modification.

Conclusions

In the largest analysis to date, we identified no evidence for effect modification by smoking status in the association between APOE genotype and risk of CHD.  相似文献   
64.
65.

Purpose

To determine a reference background urinary thallium level; to compare urinary thallium data from workers to this background level; to investigate factors affecting these levels and whether creatinine correction is appropriate.

Methods

Urine samples from non-occupationally exposed people (n = 273, from 113 individuals) and workers (n = 896, from 447 individuals) were analysed for thallium by ICP-MS. A reference background level was calculated, defined as the 95th percentile value of a non-occupationally exposed population. Worker data were divided into two subsets: thallium workers (those who work directly with thallium or its compounds) and general workers; and compared to the background level. Bayesian linear mixed effects modelling was used to investigate factors affecting urinary thallium concentration and the efficacy of creatinine correction for the determination of urinary thallium.

Results

The reference background urinary thallium level is 0.27 μmol/mol creatinine (creatinine-corrected) or 0.40 μg/l (uncorrected). Median values were 0.11 μmol/mol creatinine or 0.17 μg/l for non-occupationally exposed people, 0.12 μmol/mol creatinine or 0.20 μg/l for general workers and 0.19 μmol/mol creatinine or 0.41 μg/l for thallium workers. Variation was lower in creatinine-corrected models. Nine per cent of samples from general workers and 39 % of samples from thallium workers exceeded the creatinine-corrected background level. By 2010, 90 % of all workers had urinary thallium levels below the 95th percentile reference background level.

Conclusions

Urinary thallium concentrations were higher in thallium workers than non-occupationally exposed people and general workers. Creatinine correction is appropriate.  相似文献   
66.
Oxidative stress is considered an important factor that promotes cell death in response to a variety of pathophysiological conditions. This study investigated the antioxidant properties of allicin, the principle ingredient of garlic, on preventing oxidative stress-induced injury. The antioxidant capacities of allicin were measured by using 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and hydrogen peroxide (H2O2)-induced cell damage on H9c2 cardiomyoblasts. Allicin (0.3–10?μM) pre-incubation could concentration-dependently attenuate the intracellular reactive oxygen species (ROS) increase induced by H2O2 on H9c2 cells. It could also protect H9c2 cells against H2O2-induced cell damage. However, the DPPH free radical scavenging activity of allicin was shown to be low. Therefore, it is believed that the protective effect of allicin on H9c2 cells could inhibit intracellular ROS production instead of scavenging extracellular H2O2 or free radicals. For the observed protective effect on H9c2 cells, allicin might also be effective in reducing free radical-induced myocardial cell death in ischemic condition.  相似文献   
67.
Many therapists use thigh circumference as a measure of quadriceps size to evaluate the effect of an injury or effectiveness of an intervention. However, this technique has been shown to be unreliable, thus more accurate methods of measuring muscle size are required. The purpose of this study was to investigate the validity and reliability of measuring quadriceps cross-sectional area (CSA) with static compound B ultrasound scanning at the level of the mid-thigh. Repeated measures of known linear distances and CSAs were made with a planimetry device. Both face and criterion validity were demonstrated indicating that the device is reliable when measuring CSAs. A single rater located quadriceps muscle borders and measured CSAs on a series of ultrasound scans. A mean coefficient of variation (%CV = 1.7) was observed, signifying high intra-rater reliability. Two raters performed six scans on each of 15 subjects. Initial observation of these results suggest that the measurement of quadriceps CSA with compound B ultrasound scanning is reliable, mean %CVs = 2.8 and 1.9 for the two raters and 2.4 when their results were combined. When raters performed scans on 18 subjects on two occasions on the same day intra-class correlation coefficients (ICC) were high, 0.991 and 0.980 for raters A and B, respectively. Paired Student's t-tests revealed a significant difference (p<0.05) for Rater B between CSAs measured for initial and relocated scans. However, this difference was calculated as 1.4–2.9% and was not of clinical importance. A significant difference (p<.0.05) was observed between measurements of CSAs made by both raters on the same subject. A calibration factor was calculated for transforming the measurements of Rater B, the use of which gave comparable values. ICCs using a fixed model for inter-rater reliability were 0.963 and 0.974 for actual and trans' formed values, respectively. This study observed differences between measures obtained by different raters and recommends that the calculation and employment of a calibration factor may be useful when comparing sequential measures made by different raters.  相似文献   
68.
The Streptococcus pneumoniae polysaccharide capsule plays a role in disease severity. We assessed the association of serotype with case-fatality ratio (CFR) in invasive pneumococcal disease (IPD) and meningitis in South Africa, 2012–2018 (vaccine era), using multivariable logistic regression by manual backward elimination. The most common serotypes causing IPD were 8 and 19A. In patients <15 years of age, serotypes associated with increased CFR in IPD, compared with serotype 8 and controlling for confounding factors, were 11A, 13, 19F, 15A, and 6A. None of these serotypes were associated with increased CFR in meningitis. Among IPD patients >15 years of age, serotype 15B/C was associated with increased CFR. Among meningitis patients of all ages, serotype 1 was associated with increased CFR. PCV13 serotypes 1, 3, 6A, 19A, and 19F should be monitored, and serotypes 8, 12F, 15A, and 15B/C should be considered for inclusion in vaccines to reduce deaths caused by S. pneumoniae.  相似文献   
69.
70.
Purpose: With the advent of Bluetooth technology, many of the assistive listening devices for hearing have become manufacturer specific, with little objective information about the performance provided.

Method: Thirty native English-speaking adults (mean age 29.8) with normal hearing were tested pseudo-randomly with two major hearing aid manufacturers’ proprietary Bluetooth connectivity devices paired to the accompanying manufacturer’s specific hearing aids. Sentence recognition performance was objectively measured for each system with signals transmitted via a land-line to the same iPhone in two conditions.

Results: There was a significant effect of participant’s performance according to listening condition. There was no significant effect between device manufacturers according to listening condition, but there was a significant effect in participant’s perception of “quality of sound”.

Conclusions: Despite differences in signal transmission for each devise, when worn by participants both the systems performed equally. In fact, participants expressed personal preferences for specific technology that was largely due to their perceived quality of sound while listening to recorded signals. While further research is necessary to investigate other measures of benefit for Bluetooth connectivity devices, preliminary data suggest that in order to ensure comfort and compatibility, not only should objective measures of the patient benefit be completed, but also assessing the patient’s perception of benefit is equally important.
  • Implications for Rehabilitation
  • All professionals who work with individuals with hearing loss, become aware of the differences in the multiple choices for assistive technology readily available for hearing loss.

  • With the ever growing dispensing of Bluetooth connectivity devices coupled to hearing aids, there is an increased burden to determine whether performance differences could exist between manufacturers.

  • There is a growing need to investigate other measures of benefit for Bluetooth hearing aid connectivity devices that not only include objective measures, but also patient perception of benefit.

  相似文献   
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