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A study was carried out in order to document any abnormalities in the electro-encephalogram (EEG) that might appear in young adolescents who have deliberately inhaled the range of volatile substances loosely referred to as 'glue'. The EEGs of a group of 'street children' being assisted in a Johannesburg shelter were examined. The records were analysed for any clinical abnormalities and also subjected to spectral analysis in order to examine the overall characteristics of frequency, power and spatial distribution. The EEGs clearly revealed that, although at the time of the examination the subjects were ostensibly abstinent, both clinical and normative evidence of continuing brain disturbance was present. It was concluded that glue sniffing is likely to have long term electrocerebral sequelae.  相似文献   
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BACKGROUND: Exposure to a high level of house dust mite allergens (HDMAs) is considered as a risk factor for HDM sensitization and development of asthma in genetically disposed people. Mattresses are one of the most important sources of HDMA in people's living environment. OBJECTIVE: The aim of this study was to evaluate the association between mattress characteristics and HDMA concentrations on mattresses. METHODS: Dust samples of mattress surfaces were taken to evaluate the level of Der p 1 allergen. All participants filled in a questionnaire about the type of mattress, the type of covering (upper layer) of the mattress, dwelling characteristics and cleaning habits. Humidity and temperature of the bedroom were measured at the time of dust sampling. RESULTS: One hundred and sixty-eight questionnaires were filled in. Synthetic upper layer of the mattress was associated with a higher level of Der p 1 compared with cotton upper layer (2.6 vs. 0.8 microg/g Der p 1). Moreover, higher relative humidity (RH) was associated with significant higher concentrations and density of Der p 1. CONCLUSIONS: Two factors were associated with lower levels of Der p 1 found on mattresses, namely: a cotton upper layer of the mattress compared with a layer of synthetic material and lower RH at the time of sampling. As far as we know, the association between type of upper layer and concentration of Der p 1 has not been described before and could lead to the formulation of practical advices in order to reduce HDMA concentrations on mattresses.  相似文献   
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PURPOSE: Many studies have determined cancer patients' preferences for adjuvant therapy, for example, by asking patients the extent of benefit they would need in order to accept the therapy. However, little is known about the determinants that influence these preferences. Our research goal was to explore which determinants underlie patients' preferences by means of a literature review. METHODS: PubMed searches were conducted to identify studies in which cancer patients' preferences for adjuvant therapy had been elicited by means of a treatment preference instrument. Twenty-three papers were evaluated with regard to reported relationships between preferences and potential determinants. A total of 40 determinants were recorded and classified into one of seven categories: (1) treatment-related determinants, (2) sociodemographic characteristics and current quality of life, (3) clinical characteristics, (4) measurement instrument-related determinants, (5) time-related determinants, (6) cognitive/affective determinants, and (7) specialist-related determinants. Results: The benefit and toxicity of treatment, experience of the treatment, and having dependents (eg, children) living at home were important determinants of patients' preferences. Furthermore, qualitative data suggested that cognitive/affective and specialist-related determinants might have a large impact on patients' treatment preferences. CONCLUSION: Our results show that patients' preferences cannot fully be explained on the basis of treatment-related determinants and patient and clinical characteristics. More research is needed in the area of cognitive/affective and specialist-related determinants because of the lack of quantitative results. Furthermore, we recommend carrying out larger studies in which the (internal) relationships between determinants and preferences are assessed in the context of a cognitive cost-benefit model.  相似文献   
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Body density and body impedance at 15 selected frequencies ranging from 1 to 1350 kHz were determined in 13 subjects on four consecutive days of the week. Bioelectrical impedance at the same frequencies was also determined in 11 subjects on the same day of the week during four consecutive weeks. Day-to-day variability of body density and body impedance and week-to-week variability of body impedance were studied. Statistical analyses did not reveal significant day- or week-effects in variabilities. The mean within-person variation in body density between days was 0.0019 kg/l (CV 0.2%). Mean within-person variation in body impedance between days was 57 ohms (CV 8.7%) at 1 kHz. At 5, 50 and 100 kHz the within-person variation between days was 16 ohms (CV 2.4%), 12 ohms (CV 2.1%) and 11 ohms (CV 2.0%), respectively. Mean within-person variation between weeks was 44 ohms (CV 2.4%) at 1, 5, 50 and 100 kHz, respectively. Overall the within-subject variability in impedance at all frequencies was higher in females. The larger mean within-person variation in impedance at 1 kHz could only partly be explained by variation in body weight and may be a real error in the measurement. Electrodes with a larger surface area reduced the variability to values comparable with those at higher frequencies. The day-to-day variation in impedance at higher frequencies causes an error in calculated FFM, which is about two times larger compared to the estimated error in FFM by body density.  相似文献   
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In a multicenter study we selected 84 patients with fluctuating Parkinson's disease in order to evaluate the effects of controlled-release Sinemet 50/200 (=CR) versus standard Sinemet 25/100 (=STD) in an open-label 8-week titration period, followed by a double-blind, double-dummy 24-week treatment period. In contrast with previous double-blind studies, the efficacy of Sinemet CR proved to be significantly superior to that of Sinemet-STD according to NYUPDS and NUDS rating scales. This higher efficacy of Sinemet CR was not achieved at the expense of safety and/or tolerability. Actual total daily levodopa dosage in patients treated with Sinemet CR was increased by 33%; however, the plasma level of this dosage is calculated to be similar to that of the previous dosage of Sinemet-STD (bio-availability of Sinemet CR is 71%). Mean numbers of daily doses, off-hours, and off-periods were decreased significantly during Sinemet CR treatment. Although all other variables suggest that the number of on-hours had to be increased, statistical significance could not be reached in this respect.  相似文献   
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