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排序方式: 共有136条查询结果,搜索用时 15 毫秒
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EA Mitchell KP Nelson JMD Thompson AW Stewart BJ Taylor RPK Ford R Scragg DMO Becroft EA Allen IB Hassall A Roberts 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(8):815-818
We investigated the relationship between travel and changes in routine and the sudden infant death syndrome (SIDS) among 485 SIDS cases compared with 1800 randomly selected control infants. There was no increased risk of SIDS with travel. Special events, such as christenings, were not associated with an increased risk of SIDS. However, visits to and by friends or relatives were associated with a significantly reduced risk of SIDS after controlling for potential confounders (odds ratios = 0.70; 95% confidence interval = 0.52, 0.96). These findings may indicate less social support in SIDS cases. 相似文献
34.
Palmowski-Wolfe AM Allgayer RJ Vernaleken B Schötzau A Ruprecht KW 《Documenta ophthalmologica. Advances in ophthalmology》2006,112(3):157-168
Purpose: To study the ability and sensitivity of the slow stimulation multifocal ERG (mfERG) to detect glaucomatous damage. Methods: Right eyes of 20 patients with normal-tension glaucoma (NTG), 15 patients with high-tension glaucoma (HTG) and 15 healthy volunteers underwent testing with the mfERG (VERIS 4.1TM). The central 50 degrees of the retina were stimulated by 103 hexagons (m-sequence: 213-1, Lmax: 100 cd/m2, Lmin: 1 cd/m2, background: 50 cd/m2). Each m-sequence step was followed by 3 black frames (Lmax: < 1 cd/m2). Five response averages of the first order response component (KI) were analyzed: the central 7.5 degrees and the 4 adjoining quadrants. The amplitudes from the first minimum, N1, to the first maximum, P1, and from P1 to the second minimum, N2, were analyzed as well as the latencies of N1, P1, N2 and the latencies of 3 multifocal oscillatory potentials (mfOPs) with their maxima at about 73, 80 and 85 ms. Results: For each parameter the percentage of deviation from the mean of the control group was calculated. These values were then added for each individual to form a deviation index (DI). Seventeen patients (85.0%) with NTG and 3 patients (20.0%) with HTG showed a DI outside the normal range. The major changes were observed in the mfOPs of the NTG patients. MfOPs were then selectively filtered at 100–300 Hz and their scalar product was analyzed over an epoch of 68–105 ms. This confirmed that mfOPs differed significantly from the control in the central 7.5° and, for NTG, in the nasal field. With a logistic regression analysis the mfOPs had a sensitivity to differentiate 85% of the NTG patients and 73% of the HTG patients from normal. Conclusions: Under these conditions, the slow-stimulated mfERG can detect glaucomatous dysfunction in NTG (85.0%). The differences observed between NTG and HTG are in support of a different underlying pathomechanism. 相似文献
35.
To determine whether physical abnormalities in lung surfactant, particularly inversion of the hysteresis between surface tension and surface area, are an effective postmortem marker for sudden infant death syndrome (SIDS).
Bronchoalveolar lavage (BAL) was employed to obtain lung rinsings from 55 infants under 24 months of age at autopsy, comprising 34 index cases and 21 controls. Folch reagent was used to extract the lipoid content which was then applied at two surface concentrations, fixed and BAL-determined (BALD), to the pool of a Langmuir trough in which surface tension (γ) was measured continuously by the Wilhelmy method as surface area ( A ) was cycled.
The γ: A loops from SIDS samples were inverted relative to controls (i.e. they were hysteresis reversed, this inversion being quantified by an empirical surface tension:area reversal (STAR) score). There was a wide scatter of STAR scores, but a critical value was found which offered a significant ( P = 0.017) separation of SIDS cases from controls for a fixed surface concentration and a highly significant separation ( P = 1.0 × 10-4 ) for BALD surface concentrations. Differences in the yields of phospholipid and proteolipid, or their correlation to STAR scores, did not reach statistical significance.
Inversion of the γ: A loops (i.e. hysteresis inversion) would appear to offer a better postmortem marker of SIDS than any reported previously, the procedure having potential for development as a prospective test indicating the risk of this disease. 相似文献
Methodology:
Bronchoalveolar lavage (BAL) was employed to obtain lung rinsings from 55 infants under 24 months of age at autopsy, comprising 34 index cases and 21 controls. Folch reagent was used to extract the lipoid content which was then applied at two surface concentrations, fixed and BAL-determined (BALD), to the pool of a Langmuir trough in which surface tension (γ) was measured continuously by the Wilhelmy method as surface area ( A ) was cycled.
Results:
The γ: A loops from SIDS samples were inverted relative to controls (i.e. they were hysteresis reversed, this inversion being quantified by an empirical surface tension:area reversal (STAR) score). There was a wide scatter of STAR scores, but a critical value was found which offered a significant ( P = 0.017) separation of SIDS cases from controls for a fixed surface concentration and a highly significant separation ( P = 1.0 × 10
Conclusions:
Inversion of the γ: A loops (i.e. hysteresis inversion) would appear to offer a better postmortem marker of SIDS than any reported previously, the procedure having potential for development as a prospective test indicating the risk of this disease. 相似文献
36.
A cross sectional analytic study was undertaken on 480 married women living in a semi-urban locality in Pune, with the objective of assessing their awareness regarding factors related to child survival. It was observed that 62.1 per cent of the ladies had adequate knowledge about immunisation. A highly significant trend was evident as regards knowledge about immunisation and formal education and socio-economic status (p<0.01). 93 per cent ladies initiated breast feeding within 24 hours of birth of the new born. Significantly larger proportion of ladies from lower education favoured prolonged breast feeding (p<0.001) and favoured late introduction of top milk (p<0.001). In general, the awareness about growth chart was very poor with only 3.5 per cent ladies having adequate knowledge. Larger family size was significantly associated with declining probability of use of oral rehydration solution (ORS). Certain recommendations for improving the awareness regarding child survival have been submitted accordingly.KEYWORDS: Child survival, Health awareness 相似文献
37.
Karsten Idel Dieter Freitag Hugo Vernaleken 《Macromolecular chemistry and physics.》1976,177(10):2927-2943
By Friedel-Crafts alkylation of appropriate aromatic systems directly condensable and after modification polymerisable, complex-forming agents are obtained. Alkylation of 8-quinolinol with p-isopropenylphenol or p-isopropenylaniline gives new functional 8-quinolinols, ( 8a , b ), which in polycondensation reactions terminate the chains and make high molecular weight, thermoplastic condensation polymers with 8-quinolinol end-groups for the first time easily accessible. Reaction of metal compounds with these complex-forming polycondensates leads to chain-prolonged polymers with coordinative metal-bridges. Acylation of the functional 8-quinolinol monomers with methacryloyl chloride gives new 8-quinolinol vinyl-monomers, ( 9a , b ), which can easily be converted to homopolymers and copolymers with lateral 8-quinolinol groups. These complex-forming polymers show. particularly for heavy metals, good reversible ion-exchange properties. The metal containing polymers have various applications and can e.g. be used as depot-fertilizer or for contrast staining in electron microscopy. 相似文献
38.
Oliver W. Klaproth Marc Halbrügge Laurens R. Krol Christoph Vernaleken Thorsten O. Zander Nele Russwinkel 《Topics in Cognitive Science》2020,12(3):1012-1029
A model‐based approach for cognitive assistance is proposed to keep track of pilots' changing demands in dynamic situations. Based on model‐tracing with flight deck interactions and EEG recordings, the model is able to represent individual pilots' behavior in response to flight deck alerts. As a first application of the concept, an ACT‐R cognitive model is created using data from an empirical flight simulator study on neurophysiological signals of missed acoustic alerts. Results show that uncertainty of individual behavior representation can be significantly reduced by combining cognitive modeling with EEG data. Implications for cognitive assistance in aviation are discussed. 相似文献
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Abstract – The absorbed doses in the body of a Rando-Alderson phantom were measured in rotational panoramic radiography (OP-5) with LiF-700 crystals using conventional intensifying screens and standard collimator, as well as rare earth intensifying screens and a collimator slit of reduced width. The reduction of the absorbed doses obtained by using the latter combination was calculated. The reduction range in different regions was 0–50%. The greatest reduction was obtained in the cranial part of the phantom. In the caudal part little or no reduction was observed, probably because leakage radiation contributes substantially to the absorbed doses in this area. The average dose equivalent was calculated for organs in which measurements were made in several locations. The reduction was about 50% for these organs except for the gonads (8%). Compared to the estimated average annual dose equivalent originating from the natural background radiation sources, the dose equivalent resulting from this X-ray examination was very small except in the thyroid gland. In this organ the dose equivalent from one exposure corresponded to 36 days of natural background radiation, but it could be reduced to 18 days by using rare earth intensifying screens in combination with reduced beam width. 相似文献