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51.
A group of heterocyclic aromatic compounds, dinaphthofurans (DNFs), recently have been identified as potentially significant contaminants in freshwater sediments. In the present study, a battery of in vitro assays was used for detection of toxic effects of DNFs that are potentially associated with endocrine disruption and tumor promotion. Dinaphthofurans were found to act as relatively potent inducers of aryl hydrocarbon receptor (AhR)-mediated activity in the chemical-activated luciferase reporter gene expression DR-CALUX assay. The relative AhR-inducing potencies of DNFs were similar or even higher than relative potencies of unsubstituted polycyclic aromatic hydrocarbons (PAHs), with dinaphtho[1,2-b;2'3'-d]furan being the most potent AhR agonist. Two compounds, dinaphtho[2,1-b;2'3'-d]furan and dinaphtho[1,2-b;1'2'-d]furan, induced estrogen receptor (ER)-mediated activity in the estrogen receptor-mediated CALUX (the ER-CALUX) assay. Two types of potential tumor-promoting effects of DNFs were investigated, using in vitro bioassays for detection of inhibition of gap-junctional intercellular communication and detection of a release from contact inhibition. Although the acute inhibition of gap-junctional intercellular communication was not observed, all six tested DNFs were able to release rat liver epithelial WB-F344 cells from contact inhibition at concentrations as low as 100 nM. In summary, the present study indicated that DNFs can exert multiple biological effects in vitro, including induction of the AhR-mediated activity, release of cells from contact inhibition, and induction of ER-mediated activity.  相似文献   
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BACKGROUND: Chronic tears of the subscapularis tendon with or without associated tears of the supraspinatus and infraspinatus tendons may lead to pain and dysfunction of the shoulder. If conservative treatment fails and repair of the musculotendinous unit is impossible, transfer of the pectoralis major tendon can be attempted to substitute for lost subscapularis function. METHODS: Twenty-eight patients underwent a total of thirty consecutive pectoralis major transfers at an average age of fifty-three years. There were twelve isolated subscapularis tears and eighteen subscapularis tears associated with a tear of the supraspinatus or the supraspinatus and infraspinatus. All patients were examined clinically and with standard radiographs. RESULTS: The mean relative Constant score increased from 47% preoperatively to 70% at an average of thirty-two months postoperatively (p < 0.0001). The mean Constant scores for pain (p = 0.0009) and activities of daily living (p < 0.0001), the range of forward flexion (p < 0.05), and abduction strength (p = 0.001) also improved. Thirteen patients (14 shoulders) were very satisfied, ten patients (eleven shoulders) were satisfied, two patients (two shoulders) were disappointed, and three patients (three shoulders) were dissatisfied with the result. The average subjective shoulder value increased from 23% preoperatively to 55% postoperatively (p = 0.0009). In patients with a massive tear, the outcome was less favorable when the torn supraspinatus tendon was irreparable, as determined preoperatively or intraoperatively, than when it was reparable (average relative Constant scores, 49% and 79%, respectively; p = 0.002). CONCLUSIONS: Pectoralis major transfer results in improvement for patients with an irreparable subscapularis tear with or without an associated reparable supraspinatus tear. If an irreparable subscapularis tear is associated with an irreparable supraspinatus tear, the results are less favorable, and pectoralis major transfer may not be warranted.  相似文献   
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Four hours after having taken 10 ecstasy tablets a Grand Mal seizure occurred in a 19-year-old woman followed by coma, hyperthermia, tachycardia, tachypnea, and renal failure. After awakening she was oriented but presented with helplessness, disconcertion, hallucinations, panic attacks, and amnesic syndrome. Computed tomography and magnetic resonance imaging scans of the brain were normal. [99Tc]-hexamethylpropyleneamine oxime (HMPAO)-single photon emission computed tomography (SPECT), 20 days after intoxication, showed reduced, inhomogeneous, supratentorial tracer uptake bilaterally. Electroencephalography (EEG) disclosed diffuse slowing and occasionally generalized sharp waves. Valproic acid was begun. Except for slight amnesia, neuropsychological deficits had disappeared and [99Tc]-HMPAO-SPECT normalized, 29 days later. Decreased cortical blood flow was explained by vasoconstriction following ecstasy-induced depletion of serotonin.  相似文献   
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We examined the localization of cerebral functions in 28 patients with focal epilepsy and malformations of cortical development (MCDs). Polymicrogyria occurred in nine, hemimegalencephaly in four, heterotopia in eight, and focal cortical dysplasia (FCD) in nine cases. We used simple (sensomotor, visual) or complex (language, memory) functional magnetic resonance imaging (fMRI) paradigms. Two thirds of MCDs were activated by simple fMRI paradigms, whereas they less frequently showed activity during complex cognitive fMRI paradigms. During simple paradigms, all disturbances of cortical organization (polymicrogyria, schizencephaly, and mild-type FCD) showed activity, whereas other MCDs (disturbances of earlier steps of cortical development: hemimegalencephaly, Taylor-type FCD, and heterotopia) showed activity in only 44% (p < 0.01). The association between the pathophysiology and morphology of MCDs confirms the recently proposed classification system. Both focal neurological signs (p < 0.05) and focal electroencephalogram slowing (p < 0.05) independently correlated with MCD inactivity, confirming that fMRI showed neuronal functions of MCDs. Conclusively, fMRI visualizes the MCD functions and their relationship to the eloquent cortex, providing useful information before epilepsy surgery. Surgery of cortical organization disturbances should be cautiously performed because these malformations may participate to some degree in brain functions.  相似文献   
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Zusammenfassung Bei Lupus vulgaris sowie bei jeder anderen Tuberkulose der Mundschleimhaut ist auf eine Miterkrankung der kleinen Speicheldrüsen zu achten. Diese äußert sich in ausgeprägten älteren Erkrankungsfällen durch eine gewisse Härte des Krankheitsherdes und der Knötchen. Bei Verdacht ist histologische Untersuchung nach tief ausgeführter Probeexcision notwendig. Die Behandlung besteht in Exstirpation oder in tiefer Zerstörung mittels Kaltkaustik.  相似文献   
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