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Enzyme immunoassays and related procedures in diagnostic medical virology   总被引:1,自引:0,他引:1  
This review article describes several applications of the widely used enzyme immunoassay (EIA) procedure. EIA methods have been adapted to solve problems in diagnostic virology where sensitivity, specificity, or practicability is required. Concurrent developments in hybridoma and conjugation methods have increased significantly the use of these assays. A general overview of EIA methods is given together with typical examples of their use in diagnostic medical virology; attention is drawn to possible pitfalls. Recent advances in recombinant DNA technology have made it possible to produce highly specific nucleic acid probes that have a sensitivity approximately 100 times greater than that of EIA. Some applications of these probes are described. Although the non-labelled nucleic acid probes for use in the field are not as refined as non-labelled immunoassays, their range of applications is expected to expand rapidly in the near future.  相似文献   
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The genetic anomaly in albinism prevents adequate melanin metabolism within the fetal eye cup and stalk. This results in severe disruption of pre- and postnatal retinal development and the condition of abnormal temporal retinal projections. The obligate misrouting of retinal-geniculate-cortical projections in albinism can be detected in the topographical representation across the occiput of the visual evoked potential (VEP). Age-dependent misrouting detection methods are described which yield 100% detection rates with zero false positives across the life span. By combining appropriate state-defined neonatal recording procedures with the albino infant VEP test paradigm, the presence of aberrant optic pathway projections was observed in a 5-day-old full-term infant. Maximum asymmetry was observed within a long-latency window of the response which shifted during the postpartum period to shorter latencies. Longitudinal studies show two specific latency regions of significant VEP asymmetry. The first occurs within 40-70 ms after stimulus onset and remains constant across the age range. The second, more robust, cluster of asymmetry occurs within a longer latency window and shows an age-related shift towards shorter latencies. The decreasing latency of this asymmetry is concomitant with normal maturational changes of the evoked response. These results show that VEP misrouting can be extended to reliable albino diagnosis within the neonatal period and to the assessment of visual maturation.  相似文献   
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The clinical and electrophysiological features of a truncal myoclonus in a 55-year-old man are described. The electromyographic characteristics point toward propriospinal myoclonus. It is suggested that a myoclonic generator was released after use of ciprofloxacin, by antagonising the gamma-aminobutyric acid metabolism.  相似文献   
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BackgroundIn patients presenting with an acute coronary syndrome, left over right coronary dominance appears to be independently associated with increased long-term mortality. This could lead to decreasing numbers of patients with a left dominant coronary artery system in older age groups.MethodsWe assessed the type of coronary dominance in different age groups in postmortem angiograms that were routinely performed at autopsy between 1993 and 2007. Coronary dominance was determined by identifying the origin of the posterior descending artery and posterolateral branches on postmortem angiography. Age, gender, and cause of death were recorded from the autopsy database. The prevalence of left dominant, right dominant, and codominant systems was determined in three increasing age categories, with cutoffs based on tertiles.ResultsA total 1620 coronary angiograms were assessed; 167 were excluded because it was not possible to determine coronary dominance. The median age of all patients was 71 years; 56% were male. Of all deaths, 40% were classified as cardiac. Regarding coronary dominance, 81.2% was right, 9.1% was left, and 9.7% was codominant. Overall, a decrease in prevalence of left and codominant coronary systems was observed with increasing age in the three age cohorts (≤63years, 64–75 years, and ≥76 years) (P=.001 for overall comparison).ConclusionsIn this large autopsy cohort, the prevalence of a left dominant or codominant coronary system decreased with increasing age. These findings could relate to a slightly higher risk of mortality in case of left versus right coronary artery occlusion.  相似文献   
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