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901.
902.
Dyskinesias associated with dopaminergic treatment in idiopathic Parkinson's disease (PD) can be indistinguishable from those arising spontaneously in other conditions involving degeneration of, or damage to, the basal ganglia. However, those due to levodopa treatment of PD disappear on cessation of therapy. We report a patient with a clinical diagnosis of PD who, on levodopa treatment, developed hemiballism and chorea that were originally thought to be drug induced. However, the dyskinesias persisted despite stopping levodopa. Postmortem analysis showed a multisystem degeneration. 相似文献
903.
Eduardo Rodrigues Fregnani Fábio Ramôa Pires Rivera Daniel Quezada Ie Ming Shih Pablo Agustin Vargas Oslei Paes de Almeida 《Journal of oral pathology & medicine》2003,32(3):163-170
BACKGROUND: Calcifying odontogenic cyst (COC) is an uncommon odontogenic lesion with few studies describing its immunohistochemical profile and proliferative activity reported in the literature. METHODS: Clinical and histological features and immunohistochemical expression of cytokeratins, Mel-CAM (CD146), bcl-2, PCNA and ki-67, in 10 cases of COC were studied. RESULTS: All 10 cases affected the maxilla, eight intraosseous and two peripheral. Five central cases were cystic and three were cystic associated with odontoma, and the two extraosseous showed solid histological pattern; immunohistochemistry was positive for cytokeratins 8, 14, 19, AE1/AE3 and 34betaE12 and bcl-2 in all cases, and Mel-CAM in six cases. Proliferative activity was greater in the epithelium of central cystic COC in relation to COC associated with odontoma and peripheral lesions. CONCLUSION: Calcifying odontogenic cysts showed odontogenic cytokeratin profile and bcl-2 and Mel-CAM expression indicate that these proteins may be involved in the development of COC. There were no recurrences after surgery, irrespective of their proliferative activity. 相似文献
904.
Four cases of late onset metachromatic leucodystrophy in a family: clinical, biochemical and neuropathological studies. 总被引:1,自引:1,他引:0 下载免费PDF全文
D Alves M M Pires A Guimar?es M C Miranda 《Journal of neurology, neurosurgery, and psychiatry》1986,49(12):1417-1422
Four cases of familial metachromatic leucodystrophy are described: the age of onset ranged from 15 to 21 years. Mental deterioration was the earliest clinical sign to be noted and all progressed to severe dementia. The arylsulphatase activity in peripheral leucocytes of the patients was very low, 5 to 15 nmol/h/mg protein, moderately reduced in the heterozygote, 40 nmol/h/mg protein, compared with control values of 60-160 nmol/h/mg protein. Sural nerve biopsies in two cases showed perivascular macrophages filled with metachromatic material and electron microscopy showed typical inclusions in Schwann cell cytoplasm. Necropsy in one of the cases revealed severe demyelination mainly in the cerebral hemispheres with metachromatic material in macrophages and neurons. 相似文献
905.
Angela F. Logullo Suely Nonogaki Roberto E. Miguel Luiz P. Kowalski Inês N. Nishimoto Fátima S. Pasini Miriam H. H. Federico Ricardo R. Brentani M. Mitzi Brentani 《Journal of oral pathology & medicine》2003,32(3):139-145
BACKGROUND: Transforming growth factor beta1 (TGFbeta1) is a negative growth regulator in keratinocytes, and in vitro studies lead to the concept that loss of TGFbeta1 responsiveness is a critical step in epithelial carcinogenesis. OBJECTIVE: To investigate the prognostic relevance of TGFbeta1 expression in head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: TGFbeta1 distribution was determined by immunohistochemistry in oral cavity/oropharynx (n = 79), larynx (n = 36) and hypopharynx (n = 25) tumors and in matched normal adjacent mucosa. TGFbeta-type I and II receptors were determined in 20 cases of differentiated oral cavity/hypopharynx tumors. Cases were considered positive if displaying reactivity in >10% of the cells. RESULTS: TGFbeta1-positive expression was found in 47.2% of larynx, 36.7% of oral cavity/oropharynx and in 24% of the hypopharynx tumors. Reactivity in >60% of the cells was displayed only by 11.4% of HNSCC. All normal controls were positive. TGFbeta1-positive expression did not correlate with clinico pathological parameters. An association with differentiation was verified only in oral cavity/oropharynx tumors (P = 0.001). TGFbeta1 was also not related to 5 years survival (Kaplan-Meier). Strong and diffuse expression of TGFbeta-RII was identified in 19/20 cases regardless of TGFbeta1 immunoreactivity. Out of 17 TGFbeta1-positive oral cavity/oropharynx tumors, only nine expressed TGFbeta-RI suggesting a disruption of the TGFbeta1 pathway. We conclude that TGFbeta1 protein immunostaining is not a useful biomarker in assessment of prognosis in HNSCC. 相似文献
906.
Luiz F Pires Jose R de Macedo Manoel D de Souza Osny O S Bacchi Klaus Reichardt 《Applied radiation and isotopes》2002,57(3):375-380
The application of sewage sludge as a fertilizer on soils may cause compacted surface layers (surface sealing), which can promote changes on soil physical properties. The objective of this work was to study the use of gamma-ray computed tomography, as a diagnostic tool for the evaluation of this sealing process through the measurement of soil bulk density distribution of the soil surface layer of samples subjected to sewage sludge application. Tomographic images were taken with a first generation tomograph with a resolution of 1 mm. The image analysis opened the possibility to obtain soil bulk density profiles and average soil bulk densities of the surface layer and to detect the presence of soil surface sealing. The sealing crust thickness was estimated to be in the range of 2-4 mm. 相似文献
907.
908.
909.
910.
Further report of the occurrence of tetrodotoxin and new analogues in the Anuran family Brachycephalidae. 总被引:4,自引:0,他引:4
Osmindo R Pires Antonio Sebben Elisabeth F Schwartz Rodrigo A V Morales Carlos Bloch Carlos A Schwartz 《Toxicon》2005,45(1):73-79
Tetrodotoxin (TTX) is one of the most potent toxin already isolated, which occurs in a wide range of marine as well as terrestrial animals such as in newts and anurans. In this work, the occurrence of TTX and analogues was examined in three brachycephalid species: Brachycephalus ephippium, B. nodoterga and B. pernix using LC-FLD and LC-MS/MS. In toxicity assay (intra-peritonial injection in mice) B. nodoterga extracts were non-toxic, while B. pernix extract exhibit the highest toxicity among the studied species. Skin showed the highest toxic, followed by the liver. Retention time data in the LC-FLD system indicated the presence of TTX, 4-epiTTX, 4,9-anhydroTTX and TDA, SIM data confirmed the presence of these compounds and revealed other analogs such as 11-norTTX-6(S)-ol, 5-deoxyTTX, 11-deoxyTTX, 11-oxoTTX, 6-epiTTX. Two new components were also identified by mass spectrometry (348 and 330Da). These unknown compounds have daughter ions similar to TTX, suggesting new putative TTX analogues. 相似文献