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Salaam Semaan 《Emerging infectious diseases》2016,22(10):1863-1864
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4.
荞麦花粉抗贫血作用的实验研究 总被引:1,自引:0,他引:1
用荞麦花粉的水提取液进行了抗大白鼠缺铁性贫血的研究,结果表明:荞麦花粉具有和硫酸亚铁相似的抗缺铁性贫血作用.饮用荞麦花粉提取液35d的大白鼠,生长发育良好,主要脏器未见损害.该研究为荞麦花粉的开发利用提供了实验依据. 相似文献
5.
Summary The cerebral changes are described in a woman of 54 who suffered from Binswanger's encephalopathy: there were no signs or symptoms of chronic arterial hypertension. The disease presented as dementia of about 3 years duration. Computed tomography of the brain 2. 5 years before her death showed bilateral widespread hypodense lesions in the cerebral white matter. She died of an asthmatic attack. Autopsy disclosed extensive bilateral degeneration of the central white matter, lacunes and gliosis. Severe obliterative arteriolosclerosis occurred in the meningeal vessels and those supplying the affected parts of the brain. Light microscopy showed that the most severe lesions occurred in the arterioles. Immunohistochemistry demonstrated profound extravasation of plasma proteins chiefly albumin, indicating dysfunction of the blood-brain barrier. Thus, the lesions characteristic of Binswanger's encephalopathy may develop in the absence of chronic arterial hypertension. Additional pathogenic factors, possibly genetic predisposition to vascular injury may play a role in the development of this condition.Supported by grants from the Swedish Medical Research Council, Project No 12X-03020 and 1987 Års Stiftelse för Strokeforskning 相似文献
6.
I. Akiguchi Hidekazu Tomimoto Toshihiko Suenaga Hideaki Wakita Herbert Budka 《Acta neuropathologica》1997,95(1):78-84
Binswanger’s disease is pathologically characterized by a combination of diffuse cerebrovascular white matter lesions and
lacunar infarcts in the basal ganglia and white matter. Although a blood-brain barrier (BBB) dysfunction has been implicated
in the pathogenesis of these white matter (WM) lesions, few authors have addressed this problem. In the present study, we
describe BBB dysfunction and its regional differences in the brains of Binswanger’s disease patients. Twelve brains from Binswanger’s
disease patients (group III) were examined and compared with those from five patients with non-neurological disease (group
I) and five cortical infarct patients without significant WM lesions (group II). Immunohistochemistry was performed for glial
fibrillary acidic protein and vimentin as astroglial cell markers, and for immunoglobulins, complements and fibrinogen as
extravasated serum protein markers. The grading scores for IgG extravasation were significantly higher in group III as compared
to group I, in both the periventricular WM and the subcortical WM (P < 0.01). In group III, the scores in the periventricular WM and subcortical WM were significantly higher than in the subcortical
U fibers and cerebral cortex (P < 0.01 for the periventricular WM; P < 0.001 for the subcortical WM), respectively. Clasmatodendritic astroglia, which had swollen cell bodies and large cytoplasmic
vacuoles with disintegrated processes, incorporated the serum components IgG, IgM, C3d, C1q and fibrinogen, both in the periventricular
WM and subcortical WM in 5 out of 12 (42%) Binswanger’s disease brains. These results indicate that WM lesions in Binswanger’s
disease are accompanied by BBB dysfunction, although it remains uncertain whether BBB dysfunction is secondary to either chronic
cerebral ischemia or arterial hypertension.
Received: 25 April 1997 / Revised, accepted: 21 July 1997 相似文献
7.
Pike G. B. 《The Italian Journal of Neurological Sciences》1997,18(6):359-365
While conventional magnetic resonance imaging (MRI) measures signal primarily from the hydrogen nuclei of water, magnetization transfer (MT) MRI indirectly detects macromolecular associated hydrogen nuclei via their magnetic interaction with the observable water. In the normal adult CNS, white matter exhibits the largest MT effect due to the macromolecular content of the highly structured and lipid rich myelin. Pathologies which alter the structural integrity and the relative macromolecular-water composition, such as multiple sclerosis (MS), therefore show abnormal MT. Conventional MRI, which has a high MS lesion detection sensitivity but poor specificity in terms of differentiating the pathological state of a plaque, can thus be supplemented by MT to provide more specific information on the extent of demyelination and axonal loss. In this paper we review the basic concepts of MT imaging and its role in MS lesion characterization.Financial support was provided by the Medical Research Council of Canada, Fonds de la Recherche en Santé du Québec, and the Killam Foundation. 相似文献
8.
Leukoencephalopathy with swelling in children and adolescents: MRI patterns and differential diagnosis 总被引:7,自引:0,他引:7
M. S. van der Knaap J. Valk P. G. Barth L. M. E. Smit B. G. M. van Engelen P. Tortori Donati 《Neuroradiology》1995,37(8):679-686
In children, several neurological disorders are characterised by spongiform leukoencephalopathy. MRI of the brain typically shows white matter swelling, but does not enable differentiation of the various underlying disorders. The aim of this article is optimisation of the diagnostic value of MRI in leukoencephalopathy accompanied by swelling. MRI-based inclusion criteria were met by 20 patients in our database. The images were analysed using a detailed scoring list. In 13 of the 20 patients the clinical diagnosis was known (11 definite and 2 probable diagnoses). Characteristic MRI abnormalities could be defined in these patients. Of the 7 patients without a diagnosis, 5 had identical MRI abnormalities: difuse hemisphere swelling and typical cysts in frontoparietal subcortical white matter and the tips of the temporal lobes. The clinical picture was also similar in these patients, suggesting a similar disease. 相似文献
9.
ABSTRACT Coronaviruses (CoVs) mainly cause enteric and/or respiratory signs. Mammalian CoVs including COVID-19 (now officially named SARS-CoV-2) belong to either the Alphacoronavirus or Betacoronavirus genera. In birds, the majority of the known CoVs belong to the Gammacoronavirus genus, whilst a small number are classified as Deltacoronaviruses. Gammacoronaviruses continue to be reported in an increasing number of avian species, generally by detection of viral RNA. Apart from infectious bronchitis virus in chickens, the only avian species in which CoV has been definitively associated with disease are the turkey, pheasant and guinea fowl. Whilst there is strong evidence for recombination between gammacoronaviruses of different avian species, and between betacoronaviruses in different mammals, evidence of recombination between coronaviruses of different genera is lacking. Furthermore, the recombination of an alpha or betacoronavirus with a gammacoronavirus is extremely unlikely. For recombination to happen, the two viruses would need to be present in the same cell of the same animal at the same time, a highly unlikely scenario as they cannot replicate in the same host! 相似文献
10.
H. Kretzschmar F. Kirchner Prof. K. Takano 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,38(2):181-187
Summary Various doses of tetanus toxin were injected into three hind leg and two fore leg muscles of the rat. The neuromuscular transmission was tested by recording the mass action potential of the muscles elicited by a single electrical stimulus to the motor nerve after strong symptoms of local tetanus had developed. The muscle responses were depressed and blocked at lower toxin doses in the fast tibialis anterior than in the mixed gastrocnemius latemlis, while blocking of the slow soleus required the highest dose. The extensor carpi radialis and the flexor carpi ulnaris muscles showed medium sensitivity. In all five muscles the contraction time was measured and correlated with its individual minimal blocking dose. The more phasic (i.e., the faster) the muscle, the more sensitive its neuromuscular transmission was to tetanus toxin. The proportional distribution of red, white, and intermediate fibres, which are associated with specific end-plate types, was evaluated for the five muscles. The percentage of white fibres in the muscles displayed a very good negative correlation with the blocking dose. The relation between structures of end-plates and effects of tetanus toxin were analysed and it is suggested that the differences in sensitivity to tetanus toxin in the neuromuscular transmission in the five muscles is determined by a differential distribution of endplates with varying sensitivities to this toxin due to structural properties.This study is a part of a doctoral dissertation submitted by one of the authors (H.K.) to the Faculty of Medicine, University of Göttingen. Some of the results were presented at the 48th and 49th Congr. of German Physiol. Soc. (Kretzschmar et al., 1977, 1978) and at the 5th Internat. Conf. on Tetanus (Kretzschmar et al., 1979) 相似文献