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1.
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
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Sokolova IN Savelov NA Chistiakova OV Sorokin KV Gurariĭ LL Shatinina NN 《Arkhiv patologii》2005,67(6):38-43
59 angiomyolipomas were studied: immunohistochemistry (IHC) was used in 24 cases, electron microscopy (EM) in 6 cases. 57 tumors had a typical structure, 2 did not contain fat component. Premelanosomes were found by EM in one tumor. Smooth muscle actin was found in all tumor cells. Involvement of lymph nodes was observed in 2 patients. Histogenesis of this tumor is discussed. 相似文献
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The aim of this work, that was carried out using Wistar rats, was to characterize the response of neurons of different morphofunctional types to amphetamine administration and to study the possibility of correction of these changes by delta-sleep inducing peptide (DSIP). Single intraperitoneal injection of 60 microg/kg of DSIP following a long term amphetamine administration (2.5 mg/kg for 3 weeks) was shown to result in normalization of brain metabolism, that was disturbed by the drug. The correcting DSIP effect was found in rat brain structures judging by the parameters of the state of proteins in neurons of sensomotor cortex and caudate nucleus and by the activity of enzymes of neurotransmitter metabolism, such as type A and B monoamine oxidases and acetylcholine esterase, that was determined in subfractions of the same brain structures. DSIP modulating effect in phenamine stereotypy supports its role as an adaptogen of intercenter relations in CNS pathology. 相似文献
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Morphology of microparticles of the microencapsulated measles vaccine was studied by cryofractography, transmission electronic microscopy and by atomic force microscopy; co-polymers of polyacrylic acid and of sodium-alginate (spermidine) complexes were used as the matrix. The different-composition microcapsules had clear-cut borders and a certain range of sizes; but they were different in morphology, and their structures and densities varied identically with regard for a medium acidity, which is apparently preconditioned by some conformation-type alterations of matrix molecules. The studied preparations can, probably, protect the viral material in the stomach aggressive medium and release the material to ensure its contact with the intestine lymph tissue; thereof, they can be referred to as promising for further study of mucosal vaccines. 相似文献
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Shchelkanov MIu Kolobukhina LV Moskvina TM Aushev ID Kartoev AA Kelli EI Merkulova LN Grenkova EP Samokhvalov EI Petriaev VG Serobian AG Klimova EA Galkina IV Malyshev NA Aristova VA Slavskiĭ AA Luk'ianova NA Deriabin PG Gromashevskiĭ VL Efremenko VI Onishchenko GG L'vov DK 《Voprosy virusologii》2005,50(5):9-15
The laboratory verified cases of Crimean-Congo hemorrhagic fever (CCHF) in the piedmont steppes of the North Caucasus (Malgobeksky District, Republic of Ingushetia) are first described. The source of the first infection was Ixodidae ticks; three subsequent sources were contacts with the bloody discharges from patients. CCHF virus genome was detected in the blood of the cattle from an epidemic focus and in the pools of the Ixodes ticks Haemaphysalis parva Neum., 1897 and Boophilus annulatus Say, 1821, taken from cattle. The problem of including the piedmont steppes of the North Caucasus into the CCHF nosological area is discussed. 相似文献
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The aim of this chronic experimental study performed in 16 dogs was to determine the effect of epidural infusion of 0.01% clopheline solution on the morphological and histoenzymological characteristics of spinal ganglion neurons. Daily infusions of clopheline at the dose of 15 mg/kg for 14 days caused a decrease in capillary permeability in the spinal ganglia at the injection site and its increase in the intact areas. This finding suggests the changes in the activity of the microcirculatory bed with a disturbed interaction in capillary-neuron system. Analysis of morphometric parameters has demonstrated the presence of some functional and reversible dystrophic changes in spinal ganglion neurons, which were associated with epidural infusion of both clopheline and isotonic solution of sodium chloride. Determination of the activity of oxidation-reduction enzymes, which reflect the course of aerobic and anaerobic processes in spinal ganglion neurons, has shown no significant differences between the groups of animals infused with or isotonic solution of sodium chloride. In conditions of chronic experiment no significant variations were found in RNA content in ganglionic cells at and outside the sites of infusion of clopheline and of isotonic solution of sodium chloride. 相似文献
10.
We studied follow-up iliac mucosa biopsies from 11 patients with juvenile polyposis and 4 patients with familial adenomatous polyposis who had undergone total colectomy with mucosal proctoectomy with creation of straight ileoanal anastomosis. The biopsies that have been taken from the posterior wall of the terminal ileum show incomplete and focal neocolonic transformation of iliac mucosa. Nevertheless, in most cases iliac mucosa preserved its architectural and histochemical characteristics. Chronic inflammation in iliac mucosa is not typical for patients with polyposis. 相似文献