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Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
3.
The burden of brain diseases in Europe. 总被引:3,自引:0,他引:3
The burden [as defined by the World Health Organisation (WHO)] of brain diseases (neurological, neurosurgical and psychiatric diseases together) is very high and yet resources spent on these diseases are not necessarily commensurate with the extent of this burden. However, hard data on the burden of brain diseases in Europe have not previously been easily accessible. The Global Burden of Disease (GBD) 1990 study conducted jointly by the WHO, Harvard University and the World Bank provided new measures that are now becoming universally accepted and have been used also in a repeat study: The GBD 2000. The key parameter of the study is disability adjusted life years (DALY), which is the sum of years of life lost (YLL) caused by premature death and years of life lived with disability (YLD). In the present report, data from the GBD 2000 study and from the World Health Report 2001 on brain diseases is extracted for the territory of Europe. This territory corresponds roughly to the membership countries of the European Federation of Neurological Societies. The WHO's Report has a category called neuropsychiatric diseases, which comprises the majority but not all the brain diseases. In order to gather all brain diseases, stroke, meningitis, half of the burden of injuries and half of the burden of congenital abnormalities are added. Throughout Europe, 23% of the years of healthy life is lost and 50% of YLD are caused by brain diseases. Regarding the key summary measure of lost health, DALY, 35% are because of brain diseases. The fact that approximately one-third of all burden of disease is caused by brain diseases should have an impact on resource allocation to teaching, reasearch, health care and prevention. Although other factors are also of importance, it seems reasonable that one-third of the curriculum at medical school should deal with the brain and that one-third of life science funding should go to basic and clinical neuroscience. In addition, resource allocation to prevention, diagnosis and treatment of brain diseases should be increased to approach, at least, one-third of health care expenditure. With the present data on hand, neurologists, neurosurgeons, psychiatrists, patient organizations and basic neuroscientists have a better possibility to increase the focus on the brain. 相似文献
4.
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
5.
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
6.
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
7.
G. Fatati M. L. Amerio M. Bacci F. Brunetti A. Caretto L. Casali S. Coaccioli F. D’Andrea E. Del Toma M. Di Sapio D. Domeniconi M. Kob F. Leonardi E. Mirri P. Nanni A. Paci P. Pallini G. Ronzani A. R. Sabbatini S. G. Sukkar M. Tagliaferri G. Vincenzoni M. A. Fusco 《Mediterranean journal of nutrition and metabolism》2009,1(3):203-206
8.
The transport of L-alanine, a natural substrate of system A, across liver plasma membrane vesicle preparations was modified during the early stages of rat DENA hepatocarcinogenesis. Kinetic studies indicated an increase of the Vmax, with normal Km values, at 30 h in rats undergoing a partial hepatectomy. Normal Vmax and drastically reduced Km values were present using membrane preparations from liver tissue showing enzyme-altered hyperplastic foci and/or preneoplastic nodules. The results suggest that alanine transport is differently affected by initiating and promoting stimuli during rat DENA hepatocarcinogenesis. The changes of the Vmax could be related to the promoting effect of partial hepatectomy on cell proliferation whereas the changes of the affinity constant (Km) could be the result of intrinsic modifications of the transporter in initiated cells. 相似文献
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