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991.
During maximal breath-holding six healthy elite breath-hold divers, after an initial “easy-going” phase in which cardiovascular changes resembled the so-called “diving response”, exhibited a sudden and severe rise in blood pressure during the “struggle” phase of the maneuver. These changes may represent the first tangible expression of a defense reaction, which overrides the classic diving reflex, aiming to reduce the hypoxic damage and to break the apnea before the loss of consciousness.  相似文献   
992.
Voluntary exercise is beneficial in models of primarily neurodegenerative disorders. Whether exercise also affects inflammatory neurodegeneration is unknown. In the present study, we evaluated the clinical, synaptic and neuropathological effects of voluntary wheel running in mice with myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis. Exercising EAE mice exhibited less severe neurological deficits compared to control EAE animals. The sensitivity of striatal GABA synapses to the stimulation of cannabinoid CB1 receptors was dramatically downregulated following EAE induction, and was rescued by exercise in EAE mice with access to a running wheel. Finally, we found that exercise was able to contrast dendritic spine loss induced by EAE in striatal neurons, although the degree of inflammatory response was similar in the two experimental groups.Our work suggests that life style and experiences can impact the clinical course of inflammatory neurodegenerative diseases by affecting their synaptic bases.  相似文献   
993.
ObjectiveWe tested the hypothesis that inter-hemispheric directional functional coupling of eyes-closed resting EEG rhythms is abnormal in adolescents with Down syndrome (DS).MethodsEyes-closed resting EEG data were recorded in 38 DS adolescents (18.7 years ±0.67 SE, IQ = 49 ± 1.9 SE) and in 17 matched normal control subjects (NYoung = 19.1 years ±0.39 SE). The EEG data were recorded from 8 electrodes (Fp1, Fp2, C3, C4, T3, T4, O1, O2) referenced to vertex. EEG rhythms of interest were delta (2–4 Hz), theta (4–8 Hz), alpha 1 (8–10.5 Hz), alpha 2 (10.5–13 Hz), beta 1 (13–20 Hz), and beta 2 (20–30 Hz). Power of EEG rhythms was evaluated by FFT for control purposes, whereas inter-hemispheric directional EEG functional coupling was computed by directed transfer function (DTF).ResultsAs expected, alpha, beta, and gamma power was widely higher in NYoung than DS subjects, whereas the opposite was true for delta power. As a novelty, DTF (directionality) values globally prevailed from right to left occipital areas in NYoung subjects and in the opposite direction in DS patients. A control experiment showed that this DTF difference could not be observed in the comparison between DS adults with mild cognitive impairment and normal age-matched adults.ConclusionsThese results indicate a peculiar abnormal directional inter-hemispheric interplay in visual occipital areas of DS adolescents.SignificanceDirection of inter-hemispheric EEG functional coupling unveils a new abnormal brain network feature in DS adolescents.  相似文献   
994.
Recently, some authors detected increased frequency or new onset of migraine with aura (MA) after atrial septal defect (ASD) closure. We report the effects of ASD closure on the occurrence of MA in three patients of Parma Headache Centre. Two of them developed MA after the procedure one had a worsening of pre-existing MA. The increased frequency or the de novo onset of MA after ASD closure may be related to the alteration of some physiological variables that play a central role in the physiopathogenetic mechanisms of MA and may trigger attacks in predisposed individuals. In previous literature reports, the new pattern of MA appeared self-limiting within a few weeks or months. In our cases, it seemed to last longer, but the natural history of this headache subtype suggests that this finding could be related to the extended duration of our follow-up and to the prospective nature of our study.  相似文献   
995.
Purpose:   With the development of intensive care, the survival of extremely low-birthweight (ELBW) infants (<1,000 g) has greatly improved. The aim of our study was to report the incidence of epilepsy after a follow-up of >7 years in a population of ELBW children, born in central and southern Sardinia between 1991 and 2000.
Methods:   We analyzed data of 104 children. All infants had had serial cranial ultrasound echography (CUE) in the neonatal period and some also had magnetic resonance imaging (MRI). At last follow-up we evaluated the occurrence of epilepsy through a review of clinical charts and a structured telephone interview.
Results:   In 11 (10.6%) of 104 of children we observed febrile seizures (FS). Epilepsy occurred in 9 (8.6%) of 104 ELBW children, and in these patients a frequent positive family history for epilepsy and/or FS was present. In four epilepsy patients CUE was highly pathologic, showing intraventricular hemorrhage (IVH) of grade IV and in two mildly abnormal (IVH of grade I–II). In three additional children with normal neonatal ultrasound scan, a later magnetic resonance imaging (MRI) study revealed lesions related to neonatal insult.
Discussion:   In our ELBW population, epilepsy had an incidence clearly superior to that expected in infancy (8.6% vs. 0.6–0.8% ) . A frequent positive familiar history for epilepsy and/or FS suggests that a genetic predisposition may also play a role. Subjects with highly abnormal CUE are a subgroup with high risk for seizures; however, epilepsy can occur even with normal CUE.  相似文献   
996.
β-Amyloid (Aβ) related pathology shows a range of lesions which differ both qualitatively and quantitatively. Pathologists, to date, mainly focused on the assessment of both of these aspects but attempts to correlate the findings with clinical phenotypes are not convincing. It has been recently proposed in the same way as ι and α synuclein related lesions, also Aβ related pathology may follow a temporal evolution, i.e. distinct phases, characterized by a step-wise involvement of different brain-regions. Twenty-six independent observers reached an 81% absolute agreement while assessing the phase of Aβ, i.e. phase 1 = deposition of Aβ exclusively in neocortex, phase 2 = additionally in allocortex, phase 3 = additionally in diencephalon, phase 4 = additionally in brainstem, and phase 5 = additionally in cerebellum. These high agreement rates were reached when at least six brain regions were evaluated. Likewise, a high agreement (93%) was reached while assessing the absence/presence of cerebral amyloid angiopathy (CAA) and the type of CAA (74%) while examining the six brain regions. Of note, most of observers failed to detect capillary CAA when it was only mild and focal and thus instead of type 1, type 2 CAA was diagnosed. In conclusion, a reliable assessment of Aβ phase and presence/absence of CAA was achieved by a total of 26 observers who examined a standardized set of blocks taken from only six anatomical regions, applying commercially available reagents and by assessing them as instructed. Thus, one may consider rating of Aβ-phases as a diagnostic tool while analyzing subjects with suspected Alzheimer’s disease (AD). Because most of these blocks are currently routinely sampled by the majority of laboratories, assessment of the Aβ phase in AD is feasible even in large scale retrospective studies.  相似文献   
997.
998.
Parathyroid cancer is an uncommon malignant cancer and is associated with a poor prognosis. The staging of parathyroid cancer represents an important issue both at initial diagnosis and after surgery and medical treatment. The role of positron emission tomography/computed tomography (PET/CT) with 18F-Fluorodeoxyglucose (18F-FDG) as an imaging tool in parathyroid cancer is not clearly reported in the literature, although its impact in other cancers is well-defined. The aim of the following illustrative clinical cases is to highlight the impact of PET/CT in the management of different phases of parathyroid cancer. We describe five patients with parathyroid malignant lesions, who underwent FDG PET/CT at initial staging, restaging and post-surgery evaluation. In each patient we report the value of PET/CT comparing its findings with other common imaging modalities (e.g., CT, planar scintigraphy with 99mTc-sestamibi, magnetic resonance imaging) thus determining the complementary benefit of FDG PET/CT in parathyroid carcinoma. We hope to provide an insight into the potential role of PET/CT in assessing the extent of disease and response to treatment which are the general principles used to correctly evaluate disease status.  相似文献   
999.
1000.
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