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E Erdogan O Ongürü N Bulakbasi A Baysefer F Gezen E Timurkaynak 《Minimally invasive neurosurgery》2003,46(1):50-53
Intracerebral and intramedullary schwannomas are uncommon; but, in general, spinal intramedullary schwannomas are more frequent than intracerebral schwanomas. We present a case of right lateral ventricle schwannoma in a 21-year-old man and review the associated literature. The 21-year-old right-handed man presented with loss of the left-eye vision approximately 8 months before referral to an ophthalmologist. The patient was immediately subjected to computed tomography (CT) scan, which showed an enhanced lesion with cystic component in the right occipital horn of the lateral ventricle. And consecutively, he was admitted to our department. The tumor was evacuated via craniotomy with marked improvement in his clinical state. The postoperative course was uneventful and postoperative CT control showed no residue. On MRI control no recurrence was noted after a follow-up period of 8 years. Intracerebral schwannoma is a rare, benign neoplasm. It is usually located superficially or adjacent to a ventricle. Characteristic imaging features include cyst formation, calcification, and evidence of peritumoral edema or gliosis. The recognition of this benign and potentially curable neoplasm and its differentiation from other neoplasms, some of which have less favourable outcomes, is of obvious importance. 相似文献
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Peter Jecker Lisa A. Orloff Miriam Wohlfeil Wolf J. Mann 《European archives of oto-rhino-laryngology》2006,263(7):664-667
Chronic polypoid rhinosinusitis (CRS) is a common disease, affecting approximately 16% of the adult population in the US every year. In addition to many well known predisposing factors, an association with reflux disease is hypothesized. Such an association might explain the recurrence of polyposis in the face of improved surgical techniques and postsurgical treatment of CRS. At present it is unclear whether extraesophageal reflux directly injures the sinus mucosa, whether gastroesophageal reflux leads to vagus-mediated neuroinflammatory changes, or whether both mechanisms occur separately or simultaneously. In patients suffering from recurrent CRS (n=20) and healthy volunteers (n=20), ambulatory 24 h two channel pH testing was performed. The number of reflux events, the fraction of the total time during which pH was below 4, and the reflux area index (RAI) were determined in the esophagus as well as in the hypopharynx. Patients with recurrent CRS had significantly more reflux events in the esophagus and the fraction of pH<4 and the RAI were increased up to 10-fold compared to healthy volunteers. In contrast to the esophagus, these differences were not observed in the hypopharynx. Recurrent CRS is often associated with GERD but not with EER. Recurrent disease or prolonged recovery after surgery should raise the suspicion of reflux disease as a possible triggering factor. Because GERD itself cannot be diagnosed by laryngoscopy, and because of the subjectivity of symptoms such as heartburn, the otolaryngologist should consider double-probe pH testing as the diagnostic procedure of choice. 相似文献
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Autoradiography of brain slices from 4 multiple sclerosis (MS) and 9 control patients was performed. After 6 weeks of exposure the exact picture of the white matter appeared on the X-ray films in all cases with MS, but only in one of the controls. The high level of autoradiographic signal from MS white matter suggests that an abnormal accumulation of radioactive trace elements takes place within the brains of MS victims. 相似文献
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A monoclonal antibody against choline acetyltransferase (ChAT), the acetylcholine-synthesizing enzyme, was used to study cholinergic synapses on identified (Golgi stained) granule cells in the rat fascia dentata. Choline acetyltransferase immunocytochemistry was applied to 40-microns Vibratome sections cut perpendicular to the longitudinal axis of the hippocampus. Light microscopy revealed fine varicose ChAT-immunoreactive axons in all layers of the fascia dentata, i.e., in the stratum moleculare, the stratum granulosum, and the subgranular polymorph zone. Most fibers were observed in the vicinity of granule cell bodies where they ran mainly parallel to the granular layer. Next, the immunostained Vibratome sections were sandwiched between small pieces of Parafilm and piled to form a block that was covered with agar and Golgi stained. After that, the sections were separated by cutting away the agar and removing the Parafilm. Sections containing well-impregnated granule cells were gold-toned (Fairén et al., '77), embedded in Araldite, and subjected to ultrathin sectioning for electron microscopy. A total of 14 gold-toned granule cells were examined in the electron microscope for synaptic contacts with cholinergic afferents. Choline acetyltransferase-immunoreactive axon terminals were observed that established symmetric synaptic contacts with the cell bodies and dendritic shafts of the gold-toned identified granule cells. Two types of contact were observed on spines arising from gold-toned granule cell dendrites. Immunoreactive terminals established asymmetric synaptic contacts with the head of small spines and symmetric contacts with the stalk of large, complex spines. The boutons forming asymmetric synaptic contacts with the cup-shaped spine head of the complex spines were not found to be immunoreactive. Our results demonstrate that cholinergic fibers to the rat fascia dentata establish characteristic types of synaptic contact with different postsynaptic elements of granule cells, suggesting a complex function of this afferent system. 相似文献
100.
Exercise-induced muscle protein leakage in the rat. Effects of hormonal manipulation 总被引:2,自引:0,他引:2
Differences in exercise-induced muscle damage between males and females were studied in an animal model by measuring the serum activities of specific muscle enzymes (creatine kinase and aspartate aminotransferase). It was found that rats showed muscle damage, comparable to that observed in humans after long-term exercise: males were much more affected than females. For example, the CK activity in male rats immediately after exercise was 335% of the resting value, but remained unchanged in females. To test the hypothesis that oestrogens may protect the female muscle membrane, female rats were ovariectomized at different stages of sexual maturity and exercised. A clear effect of this hormonal manipulation was observed: operated animals showed post-exercise CK elevations, depending of the age at the time of ovariectomy. Rats, ovariectomized before reaching sexual maturity, showed more damage than those ovariectomized after reaching sexual maturity. 相似文献