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Recent studies showed hyperexcitability of the occipital cortex in subjects affected by migraine with aura. It has been shown that 1 Hz repetitive transcranial magnetic stimulation (rTMS) reduces excitability of visual cortex in normal subjects. The aim of the study was to investigate the effects of low frequency (1 Hz) rTMS on visual cortical excitability by measuring changes in phosphene threshold (PT) in subjects with migraine with aura. Thirteen patients with migraine with aura and 15 healthy controls were examined. Using a standardized transcranial magnetic stimulation protocol of the occipital cortex, we assessed the PT (the lowest magnetic stimulation intensity at which subjects just perceived phosphenes) before and after a 1-Hz rTMS train delivered at PT intensity for 15 min. The difference in the proportion of subjects reporting phosphenes in migrainer and control groups was significant (migrainers: 100% vs controls 47%; P<0.05), and 1 Hz rTMS over the occipital cortex led to a significantly increased visual cortex excitability expressed as a decrease in PT in subjects affected by migraine with aura. Conversely, after a 1-Hz TMS train normal subjects showed increased PT values, which suggests a decreased visual cortex excitability. Our findings confirm that the visual cortex is hyperexcitable in migrainers and suggest a failure of inhibitory circuits, which are unable to be upregulated by low frequency rTMS.  相似文献   
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Electrical stimulation of the Gasserian ganglion resulted in partial depletion of calcitonin gene-related peptide (CGRP) from ipsilateral central terminals of pseudounipolar primary sensory ganglion cells. Affected terminals exhibit decreased CGRP immunoreactivity as shown by cytophotometric densitomery of the caudal trigeminal nucleus. The decrease in CGRP immunoreactivity is statistically significant only in the medial one-third of the caudal trigeminal nucleus. Since earlier studies have shown that electrical stimulation of the Gasserian ganglion induces first accumulation then depletion of CGRP from perivascular sensory terminals in the dura mater, the present experiments suggest that CGRP is depleted also from central terminals of primary sensory trigeminal neurons, which might be of importance in the pathogenesis of migraine headache. Received: 18 December 1996 / Accepted: 26 June 1997  相似文献   
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The authors describe a patient who suffered two successive, right and left, strokes that caused bilateral rolandic operculum damage. The clinical picture was characterized by selective impairment of volitional facio-pharyngo-glosso-masticatory movements with sparing of automatic and reflex motor activity (Foix-Chavany-Marie syndrome). Though completely speechless, the patient was not aphasic. This dissociation is discussed in the light of the peculiar localization of lesions evidenced by CT-scan.
Sommario Viene descritta una paziente portatrice di due lesioni ischemiche coinvolgenti l'opercolo rolandico in entrambi gli emisferi. Il quadro clinico era caratterizzato da una compromissione selettiva dei movimenti volontari (con integrità di quelli automatici e riflessi) bilateralmente a livello facio-faringo-glosso-masticatorio (sindrome di Foix-Chavany-Marie). La paziente, del tutto incapace di articolazione e fonazione, non risultava afasica ad una valutazione neuropsicologica. Questa dissociazione viene discussa in riferimento alla particolare localizzazione delle lesioni alla T.A.C. cerebrale.
  相似文献   
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A micropolarimeter interfaced to a liquid chromatograph is shown to be suitable for selective monitoring of the optically-active components in complex samples. When an optically-active eluent is used, indirect determination of even optically-inactive materials is possible, down to the level of 10 ng of an injected component. If a second chromatogram is obtained using the racemic analogue of the optically-active eluent, quantitation can be achieved without standards and without prior analyte identification. This concept is also applicable to the refractive index detector, the absorption detector and the conductivity detector in the special case of ion chromatography, and the ultrasonic detector in gas chromatography.  相似文献   
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遗传因素在普通型偏头痛发生中的作用   总被引:3,自引:0,他引:3  
目的探讨遗传因素在普通型偏头痛发生中的作用及该病的遗传方式.方法以27例普通型偏头痛患者为先证者,收集其一级和二级亲属的患病资料,采用零截尾泊松分布模型判断该病有无家庭聚集性,应用Penrose法和Li-Mantel-Gart法判断该病的遗传方式,应用PPAP软件估算该病的遗传度.结果先证者一级亲属该病的患病率>二级亲属>一般人群,符合多基因遗传病的特点;Penrose法的结果也显示该病为多基因遗传病,其一级亲属的遗传度为0.935±0.098,二级亲属的遗传度为0.439±0.284,遗传度的加权平均值为0824±0.093.结论普通型偏头痛是一种多基因遗传病.  相似文献   
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ObjectiveTo know the perception and opinion of primary care health professionals on the impact of non-medicalizing group educational intervention (GRUSE) with women who present somatic symptoms without organic cause.DesignQualitative phenomenological study.SettingPrimary care health centers in Andalusia, during 2017 and 2018.Participants and/or contextsTwenty-four health professionals, selected according to their level of involvement in the GRUSE strategy (socio-educational groups).MethodA qualitative methodology is applied, through the phenomenological method. The technique used to collect the information is the discussion group, and a content analysis is carried out on it. The software Atlas.ti 8.0 is used as a support resource for the analysis.ResultsHealth professionals highlight group work as a means of achieving change, and point to the importance of intervention as a non-medicalizing strategy. They perceive that the participants obtain some benefits: the improvement of their personal well-being, the increase of their self-esteem and self-determination, and the generation of social networks, benefits that also affect their immediate surroundings.ConclusionsIn the opinion of the professionals, the strategy has positive effects on women and does not mean an increase in resources for the health system. In addition, they express the importance of provide women with tools to cope with daily life problems derivates mostly from gender mandates of a patriarchal society.  相似文献   
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Summary Whether multiple sclerosis (MS) can cause headaches is controversial. To clarify the association between headaches and MS we prospectively analyzed 104 consecutive MS patients using detailed headache evaluations. Fifty-four patients (52%) reported headaches, compared with 5 of 35 (14%) patients initially suspected to have MS but subsequently proven to have other disorders, and 18 of 100 (18%) matched general neurology patients. The MS patients had tension headaches or vascular headaches of the migraine type; there was no distinctive MS headache. Seven of these patients had headaches with their first MS symptoms, but in only one did headaches recur with disease activity. Headaches did not correlate with any clinical features of MS. We conclude that an association between headaches and MS may exist.  相似文献   
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