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An unusual combination of a fusiform aneurysm on the middle cerebral artery branch to the central region and cortical lipomatosis is described. The etiology of lipomatous disorders in the brain are multiple. The possibility of a combined dysplasia based on maldifferentiation of primitive meninges and the arterial wall is suggested in this case. Treatment consisted in uneventful, microsurgical image-guided resection of the aneurysm using the Surgiscope robotic system. 相似文献
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45.
For many years it was believed that NMR on the YBa2Cu3O6+y
family of superconductors does not support charge density variations or stripes. We discuss the NMR data of YBa2Cu3O6+y
(y > 0.63) and show that large charge density variations are actually necessary in order to explain the data. 相似文献
46.
DM Green NE Breslow JB Beckwith JZ Finklestein P Grundy PR Thomas T Kim S Shochat G Haase M Ritchey P Kelalis GJ D'Angio 《Canadian Metallurgical Quarterly》1998,16(12):3744-3751
PURPOSE: National Wilms' Tumor Study (NWTS)-4 was designed to evaluate the efficacy, toxicity, and cost of the administration of different regimens for the treatment of Wilms' tumor (WT). PATIENTS AND METHODS: Between August 6, 1986 and September 1, 1994, 905 previously untreated children aged younger than 16 years with stage II favorable histology (FH) WT (low-risk [LR]), stages III to IV FH WT, or stages I to IV clear-cell sarcoma of the kidney (high-risk[HR]) were randomized after the completion of 6 months of chemotherapy to discontinue (short) or continue for 9 additional months (long) treatment with chemotherapy regimens that included vincristine and either divided-dose (standard [STD]) courses (5 days) or single-dose (pulse-intensive [PI]) treatment with dactinomycin. HR patients also received either divided-dose (STD) courses (3 days) or single-dose (PI) treatment with doxorubicin. RESULTS: The 4-year relapse-free survival (RFS) rates after the second randomization for LR patients were 83.7% for the 190 patients treated with short and 88.2% for the 187 patients treated with long chemotherapy (P = .11). The 4-year RFS rates after the second randomization for HR FH patients were 89.7% for the 256 patients treated with short and 88.8% for the 246 patients treated with long chemotherapy (P = .87). The charge for treatment with the short PI treatment regimens for all children with stages I through IV FH WT was approximately one half of that with the long STD treatment regimens. CONCLUSION: The short administration schedule for the treatment of children with WT is no less effective than the long administration schedule and can be administered at a substantially lower total treatment cost. 相似文献
47.
MW McEnery H Haase CL Vance SJ Dubel I Morano TD Copeland Y Choi 《Canadian Metallurgical Quarterly》1997,420(1):74-78
BACKGROUND: In adults, Helicobacter pylori infection is always associated with gastritis or ulcer. However, very active gastritis and ulcers are rarely seen in children. The aim of the present work was to study the relationships between H. pylori and gastric mucosa in children. METHODS: Eighty infected children and adolescents including 48 (60%) neurologically impaired institutionalized patients, aged 2 months-22 years (mean 11.7 +/- 5.2 years) were studied retrospectively. All the patients underwent gastroscopy, and three antral and two fundic biopsy specimens were taken for histology and bacteriology. RESULTS: A normal gastric mucosa was found in 22 of 80 patients (27.5%), whereas the others had gastritis (n = 58, 72.5%). There were no statistical differences between patients with normal histology and those presenting with gastritis for age, sex, ethnic background, symptoms, and the degree of bacterial colonization. The macroscopic aspect of gastritis was less frequently found in children with a normal histology compared with those with histological gastritis (p < 0.001). CONCLUSIONS: These data show that H. pylori infection can be associated with a normal gastric histology in children. 相似文献
48.
NMR experiments on La2 – x
Sr
x
CuO4 are shown that characterize the nature of static spatial inhomogeneities in this material. Large amplitude charge density variations are found that are correlated with spin density variations. While the amplitude of the charge variation is temperature-independent, the spin variation increases Curie-like as the temperature varies and shifts toward local antiferromagnetism up to optimal doping. For x = 0.2 the correlation is independent on temperature and agrees with local incommensurability found in neutron scattering. Relations to possible scenarios are discussed. 相似文献
49.
Halorhodopsin, isolated from Halobacterium salinarium cells incubated with tritiated palmitic acid, co-elutes with labeled palmitate in phenylsepharose CL-4B chromatography. Halorhodopsin-bound 3H-palmitate is not readily displaced by prolonged exposure to a large excess of detergents and by re-chromatography of radiolabeled halorhodopsin on phenylsepharose. On other hand, the association of labeled palmitate with purified halorhodopsin is not resistant to denaturation induced either by isopropanol/hexane or by SDS gel electrophoresis. We have tested the hypothesis that tightly associated palmitate is bound to halorhodopsin through a thioester bond, which is unstable in denaturing conditions. Using GC/MS, we have analysed the reaction products of native halorhodopsin with specific thioester reagents, thiols and NaBH4, which are inactive on free fatty acids. The results of this analytical approach indicate that there is no thioester bond between halorhodopsin and palmitic acid and that palmitic acid is associated with halorhodopsin as a free fatty acid. 相似文献
50.
The presented results of investigations by surface and microanalytical methods confirm the suitability of electron beam and scanning probe techniques for process monitoring, support of process development and defect analyses in the glass industry. More and more glass and coating specialists use the high tech service provided by an external laboratory with its wide range of experience and knowledge. 相似文献