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排序方式: 共有626条查询结果,搜索用时 0 毫秒
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Central sensory and motor conduction in vitamin B12 deficiency. 总被引:7,自引:0,他引:7
V Di Lazzaro D Restuccia D Fogli R Nardone S Mazza P Tonali 《Electroencephalography and clinical neurophysiology》1992,84(5):433-439
Four patients with subacute combined degeneration were studied through upper and lower limb SEPs recorded with a non-cephalic reference montage and through cortical and spinal magnetic stimulation. Clinical signs were confined to the lower limbs in 3 patients; the remaining patient presented only paraesthesiae in 4 limbs. Median nerve SEPs showed a normal cervical N13 response with a significant increase of central conduction time concerning exclusively the P9-P14 interpeak interval. Central motor conduction to upper and lower limb muscles was abnormal. Nerve conduction studies provided no evidence of peripheral nerve involvement. These electrophysiological findings suggest that in vitamin B12 deficiency the higher segments of the cervical cord are usually affected first and that central sensory and motor conduction studies are sensitive methods for detecting such damage. 相似文献
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D A Nardone 《Archives of internal medicine》1991,151(3):617-618
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Investigation of intestine function during acute viral hepatitis using combined sugar oral loads. 下载免费PDF全文
One fifth of all cases of A virus hepatitis (AVH) have symptoms of gastroenteritis at the onset. This study investigated the mediated intestinal absorption of D-xylose (D-xyl) and 3-o-methyl-D-glucose (3-omG) and the non-mediated permeation of lactulose (Lacl, mol wt 342) and L-rhamnose (L-rh, mol wt 164) during acute and remission phases of AVH. Ten patients with AVH were given an oral load containing these sugars (5 g D-xyl: 2.5 g 3-omG, 1 g L-rh, 5 g lacl in 250 ml water) once during the acute phase and again during remission. The same load was given once to a group of 22 healthy controls. The mean concentration of D-xyl in urine and the ratio of D-xyl to 3-omG in plasma and urine were normal in both the AVH phases, ruling out intestinal malabsorption even in the acute phase. This study showed a significant increase in non-mediated permeation to Lacl, but not to L-rh, during the acute phase. These data indicate that the barrier function of the intestine is compromised in AVH infection while the absorptive function is not. An abnormally low concentration of D-xyl and 3-omG in plasma at one hour was found in all patients during the acute phase. This finding cannot be explained by alterations in intestinal absorption, but could be accounted for by increased space distribution of the sugars because of increased diffusion into tissue cells and/or expansion of the extracellular space by fluid retention. 相似文献
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Di Biase AM Pietrantoni A Tinari A Siciliano R Valenti P Antonini G Seganti L Superti F 《Journal of medical virology》2003,69(4):495-502
Lactoferrin, a member of the transferrin family of approximately 80 kDa, consists of a single polypeptide chain folded in two symmetric, globular lobes (N- and C-lobes), each able to bind one ferric ion. This glycoprotein, found in physiological fluids of mammals, plays an important role in immune regulation and in defense mechanisms against bacteria, fungi, parasites, and viruses. Although the antiviral activity of lactoferrin is one of the major biological functions of such protein, the mechanism of action is still under debate. We have investigated both the role of tryptic fragments of bovine lactoferrin and the mechanism of lactoferrin antiviral effect toward adenovirus infection in HEp-2 cells. The results obtained demonstrated that the anti-adenovirus activity of lactoferrin is mediated by the N-terminal half of the protein as the N-lobe was able to inhibit adenovirus infection, even if at lower extent than undigested lactoferrin, whereas C-lobe was ineffective. The results also showed that the anti-adenovirus action of lactoferrin and of its N-terminal peptide lactoferricin took place on virus attachment to cell membrane, mainly through competition for common glycosaminoglycan receptors. The data provide evidence that the anti-adenovirus activity of lactoferrin is mediated mainly by the cluster of positive charges at the N-terminus of whole molecule and that the N-terminal peptide lactoferricin alone is sufficient to prevent infection. 相似文献
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di Gioia CR Ciallella C d'Amati G Parroni E Nardone AM Gallo P 《Archives of pathology & laboratory medicine》2003,127(9):e367-e370
An infant with normal facies and none of the extracardiac anomalies usually associated with Williams syndrome presented at birth with an echocardiographic pattern of supravalvular pulmonary stenosis and displastic pulmonary valve. A clinical reappraisal was planned at 3 months of age, but the girl died suddenly at home at 2 months of age. At autopsy, both ventricles were hypertrophic, and the valves showed mild dysplasia. The walls of the great arteries were thick, with a "washed leather" consistency, but there was no gross evidence of discrete stenosis. The histologic mosaic appearance of the media of the great arteries, due to elastosis and extreme disarray of the elastic lamellae, prompted a postmortem diagnosis of supravalvar aortic stenosis and suggested a diagnosis of Williams syndrome, which was subsequently confirmed by fluorescence in situ hybridization. Pediatricians and pathologists should be alerted that Williams syndrome in the newborn may present as an isolated supravalvular pulmonary stenosis, whereas supravalvular aortic stenosis becomes clinically significant only a few months later. 相似文献
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Effects of lorazepam on short latency afferent inhibition and short latency intracortical inhibition in humans 总被引:2,自引:2,他引:2
V. Di Lazzaro A. Oliviero E. Saturno M. Dileone F. Pilato R. Nardone F. Ranieri G. Musumeci T. Fiorilla P. Tonali 《The Journal of physiology》2005,564(2):661-668
Experimental studies have demonstrated that the GABAergic system modulates acetylcholine release and, through GABAA receptors, tonically inhibits cholinergic activity. Little is known about the effects of GABA on the cholinergic activity in the human central nervous system. In vivo evaluation of some cholinergic circuits of the human brain has recently been introduced using a transcranial magnetic stimulation (TMS) protocol based on coupling peripheral nerve stimulation with TMS of the motor cortex. Peripheral nerve inputs have an inhibitory effect on motor cortex excitability at short intervals (short latency afferent inhibition, SAI). We investigated whether GABAA activity enhancement by lorazepam modifies SAI. We also evaluated the effects produced by lorazepam on a different TMS protocol of cortical inhibition, the short interval intracortical inhibition (SICI), which is believed to be directly related to GABAA activity. In 10 healthy volunteers, the effects of lorazepam were compared with those produced by quetiapine, a psychotropic drug with sedative effects with no appreciable affinity at cholinergic muscarinic and benzodiazepine receptors, and with those of a placebo using a randomized double-blind study design. Administration of lorazepam produced a significant increase in SICI ( F 3,9 = 3.19, P = 0.039) . In contrast to SICI, SAI was significantly reduced by lorazepam ( F 3,9 = 9.39, P = 0.0002) . Our findings demonstrate that GABAA activity enhancement determines a suppression of SAI and an increase of SICI. 相似文献