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1.
《Clinical neurophysiology》2019,130(12):2231-2237
ObjectiveThe clinical and neurophysiological characteristics of myoclonus in Angelman syndrome (AS) have been evaluated in single case or small cohorts, with contrasting results. We evaluated the features of myoclonus in a wide cohort of AS patients.MethodsWe performed polygraphic EEG-EMG recording in 24 patients with genetically confirmed AS and myoclonus. Neurophysiological investigations included jerk-locked back-averaging (JLBA), cortico-muscular coherence (CMC) and generalised partial directed coherence (GPDC). CMC and GPDC analyses were compared to those obtained from 10 healthy controls (HC).ResultsTwenty-four patients (aged 3–35 years, median 20) were evaluated. Sequences of quasi-continuous rhythmic jerks mostly occurred at alpha frequency or just below (mean 8.4 ± 1.4 Hz), without EEG correlate. JLBA did not show any clear transient preceding the jerks. CMC showed bilateral over-threshold CMC in alpha band that was prominent on the contralateral hemisphere in the patient group as compared to HC group. GPDC showed a significantly higher alpha outflow from both hemispheres toward activated muscles in the patient group, and a significantly higher beta outflow from contralateral hemisphere in the HC group.ConclusionsThese neurophysiological findings suggest a subcortical generator of myoclonus in AS.SignificanceMyoclonus in AS has not a cortical origin as previously hypothesised. 相似文献
2.
范玲 《中华产科急救电子杂志》2020,9(3):133-135
远程胎儿监护是应用互连网及计算机技术,孕妇在家中或远程监护终端将胎心监护图形传输到中央监护站,医生即可通过电脑或手机APP远程判读。对高危孕妇实行远程监护,便于及时发现胎儿宫内缺氧情况和及时处理,改善围产儿结局。 相似文献
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4.
目的 了解精神病人和正常人戒烟前后精神状况的变化及差异性 ,探讨戒烟措施。方法 对 71例精神病人和 5 0例正常人戒烟前及戒烟后 1周分别应用汉密顿焦虑量表 (HAMA)、汉密顿抑郁量表 (HAMD)、焦虑自评量表 (SAS)、抑郁自评量表 (SDS)、简明精神病量表 (BPRS )进行测评。结果 精神病人强制性戒烟前HAMA、HAMD、SAS、SDS、BPRS分值分别为 (8.2 1± 6 .4 1)、(7.6 4± 5 .71)、(36 .81± 7.14 )、(33.71± 7.1)、(2 9.4 5± 8.4 7) ;戒烟后HAMA、HAMD、SAS、SDS、BPRS分值分别为 (16 .4 5± 6 .34)、(19.73± 8.71)、(5 8.1± 12 .12 )、(5 6 .31± 11.4 )、(37.32± 7.95 ) ;戒烟前后 5种量表分值变化与正常人戒烟前后分值变化比较有极显著性差异(P <0 .0 1)。结论 对精神病人强制性戒烟可引起明显的情绪反应 ,应适宜控制病人吸烟 ,建立一个合理的管理制度 相似文献
5.
The guinea pig maximization test (GPMT) of Magnusson and Kligman was published in 1969. Since then, a vast body of practical experience with the test has been accumulated. New information requires that certain aspects of the procedure be reevaluated, especially with regard to the interpretation of challenge results. In particular, awareness of the phenomenon of hyperirritable skin (the 'angry back' phenomenon) suggests that presently used controls are not always adequate and may overstate allergenicity owing to false-positive reactions. The control group should be exposed to a chemical insult at induction which provokes an inflammatory reaction comparable to the test substance. We present strategies to distinguish irritant from allergic responses. Allergic reactions should persist on rechallenge weeks later, while nonspecific irritant reactions generally fade and are irreproducible in particular animals. Finally, when a chemical is identified as a contact sensitizer of risk is necessary to estimate the relevance of the test result to usage in the real world. 相似文献
6.
遥感技术在蚊虫孳生地监测中的应用 总被引:2,自引:0,他引:2
遥感技术作为一种快速、有效的监测工具,目前在国外已越来越多地应用于蚊虫调查和防治研究中。本文就遥感技术的原理、方法、以及在蚊虫研究中的应用作一概述,并对遥感在我国蚊虫研究的应用前景予以展望。 相似文献
7.
V. UMBRAIN J. D'HAESE M. ALAFANDY E. DE ROOVER A. SCHOUTENS B. VAN GANSBEKE A. ALBERT G. GOFFINET F. CAMU F. J. LEGROS 《Acta anaesthesiologica Scandinavica》1997,41(1):25-34
Background: Liposomes containing local anaesthetics have been administered intrathecally and in the epidural space. Poor attention has been given to the pharmacokinetics of liposomes as drug carriers. Therefore, we observed the biodistribution of liposomes after intrathecal injection in rats by scintigraphic imaging during 24 h.
Methods: We administered99 Tc-labeled multilamellar (MLV) and small unilamellar vesicles (SUV) of defined size and volume dispersities into the cerebrospinal fluid at the lumbar level. Those vesicles were free of contamination by radiolabeled colloids as visualized by light and electron microscopy and of neurotoxic products from phosphatidylcholine hydrolysis and peroxidation, both during the preparation process and after 24 h incubation in cerebrospinal fluid at 37°C in vitro.
Results: SUV immediately diffused from the lumbar site of injection to the head and were cleared between 1 and 24 h after injection. MLV were cleared more slowly from the spinal space and appeared in the head region 1 h after injection where they accumulated up to 24 h. These differences were explained in terms of vesicle sizes and volumes. SUV with 0.05 μm diameters were rapidly absorbed into the blood through the arachnoid granulations. In contrast, particles larger than the upper size limit of the arachnoid granulations permeability (±8 μm) could accumulate in the head with a slow elimination rate.
Conclusion: This difference in clearance from the intrathecal space outlines the importance of defining the size of the liposomes, the distribution of a tracer or a drug inside the liposomal preparation, the chemical stability and the absence of toxic degradation products of liposome formulations before clinical use. 相似文献
Methods: We administered
Results: SUV immediately diffused from the lumbar site of injection to the head and were cleared between 1 and 24 h after injection. MLV were cleared more slowly from the spinal space and appeared in the head region 1 h after injection where they accumulated up to 24 h. These differences were explained in terms of vesicle sizes and volumes. SUV with 0.05 μm diameters were rapidly absorbed into the blood through the arachnoid granulations. In contrast, particles larger than the upper size limit of the arachnoid granulations permeability (±8 μm) could accumulate in the head with a slow elimination rate.
Conclusion: This difference in clearance from the intrathecal space outlines the importance of defining the size of the liposomes, the distribution of a tracer or a drug inside the liposomal preparation, the chemical stability and the absence of toxic degradation products of liposome formulations before clinical use. 相似文献
8.
AMADORI DINO; NANNI ORIANA; RICCI MIRANDA; FALCINI FABIO; DECARLI ADRIANO; PALLI DOMENICO; BUIATTI EVA 《European journal of public health》1995,5(3):209-214
The aim of the present study is to evaluate drawbacks and advantagesof the choice of hospital versus population controls in a casecontrol study on diet and cancer through the analysis of a retrospectivestudy on diet and gastric cancer (GC) conducted in Forli, Italy,involving 232 cases, 430 population controls and 252 hospitalizedcontrols. The present paper reports the comparison of resultson diet and GC risk obtained using the 2 types of controls.Population controls tended, in general, to eat all kinds offoods slightly more frequently (bread, pasta, cold cuts, freshfish, seasoned cheeses, legumes, garlic, onions and preservedfruits), with the exception of cooked vegetables, which werereported less frequently by population than by hospital controls.ORs for specific foods adjusted for confounders and other foodswere consistent in the separate models including populationand hospital controls respectively for all food groups, withthe exception of cooked vegetables which represented a protectivefactor only when hospital controls were considered (high consumers,population controls: adjusted, OR=0.9, trend p value 0.54; highconsumers, hospital controls, adjusted OR=0.5, trend p value<0.01). Hospital controls were slightly less often currentsmokers (22.6 versus 30.0%) and more often regular wine drinkers(57.5 versus 47.8%) compared with population controls, but noneof these variables was associated with GC risk. The main resultsin this study were consistent using both types of controls,nevertheless the distribution of some dietary variables notrelated to the disease under study differed between the 2 controlgroups, suggesting some caution in the use of hospital controlswhen studying diseases other than GC. 相似文献
9.
The purpose of this study was to determine whether the late component of somatosensory evoked potentials (SEP) induced by electrical tooth stimulation and pain intensity are inhibited by heterotopic ischemic stimulation. The tourniquet pressure with 50 mmHg greater than the individual's systolic pressure was applied to the left upper arm for 10 min as ischemic conditioning stimulation. The late component of SEP and visual analogue scale (VAS) were recorded at 4 times and both were significantly decreased when ischemic conditioning stimulation was applied. The maximum reductions in SEP amplitude and the VAS value were 26.1% and 21.2%, respectively, during ischemic conditioning stimulation. After-effect was observed 5 min after removal of the conditioning stimulation. The present study revealed that heterotopic ischemic stimulation attenuated the late component of SEP induced by electrical tooth stimulation, triggering diffuse noxious inhibitory controls (DNIC) and after-effects in the trigeminal nerve territory. It was also suggested that the DNIC effect differs, depending on the intensity, kind, and quality of the test and conditioning stimuli. 相似文献
10.
Ken Dewitte Marc Claeys Emeline Van Craenenbroeck Koen Monsieurs Hein Heidbuchel Vicky Hoymans Tibor Stoop 《Pathophysiology》2019,26(1):53-59