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51.
Luiz C M Pereira Vanessa N Palter Anthony E Lang William D Hutchison Andres M Lozano Jonathan O Dostrovsky 《Movement disorders》2004,19(12):1485-1492
The pathophysiological changes in neural activity that characterize multiple system atrophy (MSA) are largely unknown. We recorded the activity of pallidal neurons in 3 patients with clinical and radiological features of MSA who underwent unilateral microelectrode-guided pallidotomy for disabling parkinsonism. Findings in these patients were compared with 4 control patients with a clinical diagnosis of Parkinson's disease (PD). The position, firing rates, and firing patterns of single neurons in the pallidal complex were analyzed in both MSA and PD patients. The mean spontaneous firing rate of neurons in the internal segment of the globus pallidus internus (GPii) was significantly lower in MSA than in PD patients. There were no significant differences between MSA and PD patients, however, in firing rates of neurons in the external globus pallidus (GPe) or in the external segment of GPi (GPie). In addition, no significant differences in firing pattern were found between MSA and PD patients. In conclusion, this study has shown that firing rates of neurons in GPii but not in GPie and GPe are different in MSA patients compared with that in PD patients, a finding that may reflect the poor clinical results of pallidotomy reported in patients with MSA. 相似文献
52.
J. Francisco Salomão Sérgio Cavalheiro Hamilton Matushita René D. Leibinger Antonio R. Bellas Elide Vanazzi Luiz A. M. de Souza Andréa G. Nardi 《Child's nervous system》2006,22(3):234-242
Background Cystic dysraphic lesions of the cervical and upper thoracic region are rare and only a few series have been published about the topic. These malformations can be divided into categories that include both myelocystoceles and the so-called cervical meningoceles or myelomeningoceles.Methods A retrospective study of 18 patients was conducted.Results In 17 patients a squamous or a cicatricial epithelium of variable thickness covered the dome of the lesions, while the base was covered with full-thickness skin. In one case the skin was entirely normal. Four patients displayed associated CNS malformations and three more had systemic congenital anomalies. All patients underwent surgical exploration and the length of time between birth and surgery ranged from 6 h to 9 months. The most frequent surgical finding, seen in 14 patients, was a stalk connecting the dorsal surface of the spinal cord to the cyst. In three patients the findings were consistent with myelocystocele. Only in one case was a true meningocele found. Hydrocephalus and Chiari II malformation were not as consistently associated as in myelomeningoceles. Neurological signs and symptoms were not so marked as in myelomeningoceles and were found in the follow-up of four patients. In two of them there was a non-progressive deficit, probably expressing an imperceptible involvement of the nervous system in the first year of life. The histopathological findings were of three types: neuroglial stalks, fibrovascular stalks and myelocystoceles.Conclusions Cystic dysraphisms of the cervical and upper thoracic region differ clinically and structurally from meningomyelocele and have a more favorable outcome. We believe that these malformations have not been properly labeled and propose a classification based on the structures found inside the cyst. 相似文献
53.
Enrico Verrina Barbara Andreetta Sergio Bassi Roberto Bonaudo Domenica A. Caringella Alfonso Castellani Pierluigi Cavalli Alberto Edefonti Giancarlo Lavoratti Luigi Longo Ivana Pela Rosa Penza Francesco Perfumo Virgilio Petrucci Marina Picca Mauro Ragaiolo Stefano Rinaldi Gianfranco Rizzoni Palma Sorino Giusto Viglino Graziella Zacchello Rosanna Gusmano 《Pediatric nephrology (Berlin, Germany)》1992,6(1):78-81
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%. 相似文献
54.
55.
D. Maimone P. Annunziata C. Cioni A. Leonardi G. C. Guazzi 《Acta neurologica Scandinavica》1994,90(4):285-292
Human immunodeficiency virus type 1 (HIV-1)-infected individuals frequently develop a broad spectrum of neurological syndromes, classified as HIV-1-associated cognitive/motor complex. Diffuse demyelination of hemispheric white matter is a commonly observed in HIV-1 infected brain, but the events leading to myelin destruction are still obscure. Since oligodendrocyte infection by HIV-1 is not proven as yet, myelin damage in HIV-1 infection may result from indirect mechanisms such as the excessive release of myelinotoxic substances or the triggering of autoimmune responses directed to myelin constituents. To verify the latter hypothesis, we searched for elevated anti-myelin basic protein (MBP) IgG levels in the cerebrospinal fluid (CSF) and serum of 25 patients with HIV-1 infection, 12 with multiple sclerosis (MS), and 9 with non-inflammatory neurological diseases (NIND). CSF, but not serum, anti-MBP IgG levels were more frequently elevated in HIV-1+ (16/25, 64%) than in MS (3/12, 25%) or NIND (0/9) patients. By using the anti-MBP IgG index, the anti-MBP IgG antibody specificity index (ASI), and the search for anti-MBP oligoclonal IgG, we ascertained that anti-MBP IgG were produced within the CNS in 13 of 25 (52%) HIV-1+ , in 6 of 12 (50%) MS, and in none of NIND patients. The incidence of increased CSF anti-MBP IgG levels was higher among HIV-1+ patients at stage II–III (4/4, 100%) or at stage IV B (7/9, 78%) than among those at stage IV C–IV D (5/12, 42%). Although our data indicate that intrathecal anti-MBP IgG may occur early during HIV-1 infection and that they are more common in patients with HIV-1-associated cognitive/motor complex, the possible demyelinating role of these antibodies remains to be demonstrated. 相似文献
56.
Catalina Betancur Carmen Sandi Sergio Vitiello Jos Borrell Carmen Guaza Pierre J. Neveu 《Brain research》1992,589(2):302-306
Asymmetry in brain modulation of the immune system has been previously described. In mice, paw preference has been shown to be associated with immune reactivity but the mechanisms involved in such an association are not yet known. The autonomic nervous system and the neuroendocrine system are considered as major candidates for neural influences on the immune system. In the present study, the activity of the hypothalamic-pituitary-adrenal (HPA) axis of adult female mice selected for paw preference (left-handers vs. right-handers) was assessed by measuring both adrenocorticotropic hormone (ACTH) and corticosterone plasma levels, as well as the in vitro responses of hypothalamus and adrenocortical cells to various hormone releasing stimuli. The results reported here showed no difference in the activity of the HPA axis between left- and right-handed mice, suggesting that this neuroendocrine axis is not implicated in the association between functional brain asymmetry and immune reactivity. However, our results do not exclude the possibility that the HPA axis could play a role in such an association under other circumstances, such as during development or stressful situations. 相似文献
57.
Achiléa Lisboa Bittencourt M.D. Nubia Mendonça M.D. Luiz Antonio Rodrigues de Freitas M.D. Bertram Schnitzer 《Pediatric dermatology》1992,9(2):117-122
An 8-year-old boy was seen with a cutaneous Ki-1 anaplastic, large cell lymphoma with multiple lesions. Some of the lesions showed spontaneous regression. During more than seven years of disease no systemic involvement was observed, but recurrent, self-healing lesions did appear. Histopathologic examination of five lesions revealed a variety of findings, from an inflammatory infiltrate to a highly anaplastic pattern. The neoplastic cells expressed Ki-1 and leukocyte common antigens. Ultrastructurally, those cells showed ruffled indentations. The differential diagnosis includes microvillous malignant lymphoma. The patient has had a four-year follow-up without relapses. 相似文献
58.
59.
Evaluation of five monoclonal antibody-based kits or reagents for the identification and culture confirmation of herpes simplex virus.
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Five immunofluorescence (IF) kits or reagents (Bartels [Bartels Immunodiagnostic Supplies, Inc., Bellevue, Wash.], Imagen [CellTech Diagnostics, Ltd., distributed by Analytab Products, Plainview, N.Y.], Ortho [Ortho Diagnostics Systems, Inc., Raritan, N.J.], Syva [Syva Co., Palo Alto, Calif.], Whittaker [Whittaker Bioproducts, Walkersville, Md.]) were evaluated for typing and laboratory confirmation of herpes simplex virus (HSV). Of 101 clinical isolates tested by each kit or reagent, results for 97 of them were in agreement. Identification of the four isolates with discordant results was performed by restriction endonuclease analysis of the viral DNA. The sensitivity and specificity of the Imagen and Bartels kits were 100%. For the Ortho, Syva, and Whittaker kits or reagents, the HSV type 1 (HSV-1) and HSV type 2 (HSV-2) sensitivities were 97.4 and 100%, 100 and 100%, and 97.4 and 100%, respectively, and the specificities were 100 and 97.4%, 100 and 92.4%, and 100 and 97.4%, respectively. There was one false-positive HSV-2 isolate identified by each of the Ortho and Whittaker kits or reagents. Three false-positive HSV-2 isolates occurred by staining with Syva, giving the erroneous indication of dual isolates. Several isolates stained with Imagen and Whittaker reagents displayed dull IF patterns. A dull green background occurred in ca. one-third of the HSV-2 isolates tested with the Ortho kit. The intensities of IF staining by the Bartels and Syva kits were satisfactory; however, the latter displayed a specificity of 92.7%. A total of 38 and 63 specimens were finally designated as HSV-1 and HSV-2, respectively. Identification of each isolate with the Bartels kit was consistently interpretable and is recommended as the typing and confirmatory assay of choice. 相似文献
60.
聚合酶链反应检测尖锐湿疣皮损内人乳头瘤病毒 总被引:7,自引:0,他引:7
13个皮损组织取自13例尖锐湿疣(CA)患者,13例基底细胞上皮瘤(BCC)组织作为对照,用溴化钠液分离表真皮,从组织中提出的 DNA和溴化钠液分别用聚合酶链反应检测 HPV DNA。11例CA表皮中检出 HPV DNA,HPV6有7例,HPV11有4例。3例CA真皮中发现有HPV DNA,HPV6有2例,HPV11有1例。2例标本因溴化钠液被HPV污染未作统计。在BCC组织中未发现有HPV DNA。在某些CA真皮内含有 HPV DNA可以解释散发病例的复发性。 相似文献