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Medulloblasoma is a common posterior fossa tumor seen in children and presents with some typical features like midline vermian location and fairly homogeneous enhancment. Desmoplastic variety of medulloblastoma is usually seen in the adults and is known to show some atypical features like lateral cerebellar location, variable enhancement, and early meningeal infilteration. Therefore medulloblastoma should always be considered in differential diagnosis of posterior fossa mass in adults even when typical imaging findings are not that of medulloblastoma. Enhancement pattern can be variable in these tumors varying from mild to striking. Occasionally, totally non-enhancing tumors are encountered, which can cause further diagnostic confusion. We describe the magnetic resonance (MR) and MR spectroscopy findings in a case of midline vermian mass, which did not show any enhancement on post-contrast images, and was subsequently proven to be desmoplastic medulloblastoma. On MR spectroscopy, the mass showed elevated choline peak consistent with mitotic lesion. No significant lipid lactate leak was seen, which is also consistent with the ususally homogeneous nature of these tumors. Moreover, it displayed taurine peak at 3.4 ppm which is considered fairly specific for medulloblastoma. Therefore, MR spectroscopy findings can be helpful in the diagnosis of medulloblastoma in adults when MR imaging findings can be nonspecific.  相似文献   
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A number of physiological changes occur during pregnancy and amongst them, audiological and nasal changes are quite significant. These are mainly due to the changing levels of sex hormones and return to normal once the pregnancy is over. This study was conducted to document these changes. Forty (pregnant 40 and non-pregnant 40) consenting subjects in age group of 20–35 years were assigned to test and control groups. They underwent complete ENT and Obstetric examination. In test group Pure Tone Audiometry was performed in all trimesters of pregnancy and within 3 months of delivery. The subjects in the control group underwent pure tone audiometry only once. The nasal patency was measured by Gertner’s plate method. Results from each trimester and postpartum period were compared. A highly significant difference in pure tone thresholds was observed at frequencies ranging from 125 to 1000 Hz (P < 0.001). However frequencies higher than 1000 Hz demonstrated no significant correlation. Nasal patency as measured by mean area of vapour condensation in all trimesters and control groups was highly significant (P < 0.001). The results of this study confirm that these changes occur in the first trimester and gradually improve during the subsequent trimesters returning to normal in post partum period. However number of pregnancies bear no relationship with these changes  相似文献   
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Ethylcellulose inserts of niridazole fabricated by casting were studied for in vitro release and in vivo clinical effectiveness. The in vitro drug release was steady and sustained for over 7 days and followed diffusion kinetics. Selected batch, EN3, was evaluated clinically in patients with periodontitis for 6 months. A significant improvement (α ≤ 0.05) in clinical indices from baseline was observed. Intergroup study revealed a significant (α ≤ 0.01) change in the bleeding index, gingival index, plaque index, calculus criteria, and pocket depth. Significant reduction in total bacterial count in gingival crevicular fluid was observed before and postdevice insertion, as well as between control and treatment groups.  相似文献   
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