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61.
62.
Metastases of distant primary tumors on the parotid gland are very rare. Tumor‐to‐tumor metastasis to salivary gland tumors is extremely rare. A case of a 69‐year‐old woman with a large left parotid gland mass with no previous salivary gland problems or cancer. Fine‐needle aspiration (FNA) showed evidence of a Warthin tumor. A total left parotidectomy was performed. The final pathology report showed a Warthin tumor containing two metastases of adenocarcinoma. The immunohistochemistry of the metastases led to the diagnosis of primary breast cancer. A negative FNA does not rule out the possibility of a malignant parotid tumor or metastasis, and a parotid lump should be presumed to be a secondary tumor until proven otherwise if the patient has a history of any distant primary cancer. Our patient case serves as a reminder that a new distant primary cancer might be the cause of a parotid lump.  相似文献   
63.
From the Finnish Twin Cohort (n = 27,100 pairs with known zygosity) all cases of diagnosed multiple sclerosis (MS) were reviewed and those with clinically verified MS were invited for further examinations at the Institute of Occupational Health, Helsinki, with their co-twins. Twenty one cases (19 pairs, of which 17 were discordant) fulfilled the strict criteria of MS. Detailed occupational history showed exposure to a mixture of solvents in six subjects, to lead in one, and to trichloroethylene in one. Of these seven, two monozygotic twins had MS whereas the other five cases were healthy co-twins. These results do not support a causal association between occupational exposure to chemicals and the aetiopathogenesis of MS.  相似文献   
64.
Prevalence and Prognosis of Epilepsy in Patients with Multiple Sclerosis   总被引:9,自引:5,他引:4  
An analysis of 599 clinically definite multiple sclerosis (MS) patients including all known cases of the southern province of Finland in January 1, 1979 revealed epileptic seizures in 21 (3.5%) patients. On that date, 12 patients needed treatment (2.0%). The age-adjusted prevalence of active epilepsy was significantly higher than that in the general population. The percentage of partial seizures (67%) was significantly increased in proportion to a series of 100 adult epilepsy patients, with a comparable age distribution. In 10 patients (including three patients with symptomatic epilepsy), the attacks appeared before the MS symptoms. The mean follow-up after the first seizures was 19.3 years. In 10 patients, the seizures disappeared totally during the surveillance until September 1985. Our results show an increased comorbidity between MS and epilepsy. In most cases, however, the prognosis of epilepsy was good and there seemed not to be any clear correlation between the severity of MS and epilepsy.  相似文献   
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We studied 6 patients with idiopathic optic neuritis (ON) after a mean follow-up period of 12 years. No evidence of multiple sclerosis (MS) was found on clinical grounds, nor by magnetic resonance imaging (MRI) or evoked responses. Levels of spontaneous proliferation, serum gamma-interferon (IFN-gamma) and lymphocyte MHC locus II antigen were similar in ON and in 6 patients with progressive MS, but different in healthy controls. This suggests that similar immunological conditions in vivo prevail after an idiopathic ON and in MS. A normal PHA-induced interleukin-2 receptor expression and lymphocyte proliferation but a low IFN-gamma secretion and MHC locus II antigen expression were observed. This suggests that an ON and MS defect is expressed after an interleukin-2 receptor ligand but before IFN-gamma secretion. Our findings also suggest that immunological factors do not explain the neuropathological confinement of the lesions in ON but the protective influence may rather be exerted by some as yet undefined genetic influence or may be explained by the different etiology of ON and MS.  相似文献   
67.
Heparin-Binding Growth-Associated Molecule (HB-GAM)/pleiotrophin is an 18 kDa extracellular matrix- and cell-surface-associated protein shown to enhance neurite outgrowth of perinatal forebrain neurones in vitro. The heparan sulphate proteoglycan N-syndecan ( 1 ) has been isolated as a receptor/coreceptor for the HB-GAM. We have investigated, whether HB-GAM and N-syndecan could have a similar role in neurite outgrowth and axon guidance in early axonal tracts of brain. In the present study N-syndecan was found to be spatiotemporally associated with the developing axonal tracts already on embryonic day 9 in rat, as revealed by coexpression with class III β-tubulin, which is one of the earliest neuronal markers ( 2 ; 3 ). Later, N-syndecan and HB-GAM were detected in the first afferent serotonergic projections arising from the pontine raphe nuclei. The expression pattern of HB-GAM peaked in the developing rhombencephalon at embryonic stage (E) 13–14. At the same time, N-syndecan was expressed in the developing raphe neurones growing neurites towards the diencephalon along HB-GAM immunoreactive pathways. When rhombencephalic neurones were cultured on decreasing concentrations of substrate-bound HB-GAM, E13 neurones showed a significantly better neurite outgrowth response than E11, E16 or E18 neurones. The neurite outgrowth of raphe neurones in vitro was inhibited by adding soluble heparin or N-syndecan into the culture medium, whereas addition of chondroitin sulphate had no effect. In a simple pathway assay, E13 raphe neurones selectively preferred attaching and growing neurites on pathways containing HB-GAM as compared with regions containing either laminin or fibronectin alone. Our results suggest that HB-GAM may function as a developmentally regulated cue for rhombencephalic neurones that possess N-syndecan on their cell membrane.  相似文献   
68.
Neuroactive steroids can either potentiate or inhibit a variety of membrane channels. Most studies have suggested that the effects are mediated by specific association of the steroid with the affected channel. However, a recent study of the rho1 (GABA-C) receptor (Mol Pharmacol 66:56-69, 2004) concluded that the actions were consistent with an action of the steroid in the lipid bilayer to alter the lateral pressure profile in the membrane. The enantiomers of an optically active compound are expected to have identical physical properties, including interactions with hydrophobic portions of the cell membrane. We have used two pairs of enantiomers (pregnanolone and ent-pregnanolone, allopregnanolone and ent-allopregnanolone) and show that the ability to potentiate (allopregnanolone) or inhibit (pregnanolone) the rho1 receptor is enantioselective. Therefore, these results strongly suggest that the actions of these neuroactive steroids are mediated by interactions with chiral regions of the target protein, rather than by a change in membrane properties (including lateral pressure).  相似文献   
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70.
Arteriomegaly     
The features of a patient with arteriomegaly of thoracic and abdominal aorta, common and external iliac, and femoral arteries are described.  相似文献   
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