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排序方式: 共有546条查询结果,搜索用时 15 毫秒
71.
Monoclonal antibody AM-3 (MAb AM-3) raised against a sialomucin from human colorectal carcinoma has previously been shown to define a carbohydrate epitope, which is detectable by immunocytochemistry on all investigated colonic carcinomas and is expressed in correlation with the grade of dysplasia in colonic adenomas (Hanski et al., J. Clin. Pathol., 43: 379-385, 1990). Epitope analyses in solid-phase enzyme immunoassays revealed that AM-3 antibody recognizes the sialylated Lewis(x) sequence on a branched O-linked glycan and its reductively cleaved alditol from human amniotic mucins. In comparative binding and binding inhibition studies MAbs AM-3 and CSLEX1 displayed reciprocal affinities to mucins versus gangliosides. Correspondingly, the weaker binding activities of AM-3 versus CSLEX to III3-alpha Fuc-IV3-alpha NeuAc-nLcOse4-Cer or to monogangliosides from human granulocytes were measured. Gangliosides from a human colon carcinoma were recognized by MAb CSLEX1 exhibiting a broader specificity to various sialyl-Lewis(x) antigens and by MAb FH6 reactive to sialyl-dimeric Lewis(x) antigen, but not by MAb AM-3. In conclusion, MAb AM-3 is distinguished from other sialyl Lewis(x)-specific MAbs by its selective reactivity to mucin-carried epitopes on the monomeric antigen. 相似文献
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Kerstin Konrad Susanne Neufang Charlotte Hanisch Gereon R Fink Beate Herpertz-Dahlmann 《Neuropsychopharmacology》2006,59(7):643-651
BACKGROUND: Although there is evidence for attentional dysfunction in children with attention deficit/hyperactivity disorder (ADHD), the neural basis of these deficits remains poorly understood. METHODS: We used event-related functional magnetic resonance imaging (fMRI) to investigate brain activations related to three particular aspects of attention: alerting, reorienting, and executive control. Sixteen medication-naive boys with ADHD and 16 healthy boys, aged 8 to 12 years, were studied. RESULTS: Behaviorally, children with ADHD showed a significant impairment only in their executive control system compared to healthy subjects. Neurally, children with ADHD (relative to controls) recruited deviant brain regions for all three attentional networks: less right-sided activation in the anterior cingulate gyrus during alerting, more fronto-striatal-insular activation during reorienting, and less fronto-striatal activation for executive control. ADHD symptom severity was associated with dysregulation of the blood oxygen level dependent (BOLD) signal within the putamen during reorienting and executive control. CONCLUSIONS: Our results demonstrated altered brain mechanism in ADHD associated with all three attentional networks investigated. For alerting and executive attention, our data indicate a deviant mechanism of cortical control, while ADHD children may have adopted altered strategies for reorienting of attention. Our results also stress the etiological role of functional abnormalities in the putamen in medication-naive ADHD. 相似文献
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Konrad K Neufang S Thiel CM Specht K Hanisch C Fan J Herpertz-Dahlmann B Fink GR 《NeuroImage》2005,28(2):429-439
Data on the development of the attentional systems remain scarce. We used structural and event-related functional magnetic resonance imaging to investigate differences in the neural mechanisms associated with alerting, reorienting, and executive control of attention between children (ages 8 to 12 years) and adults, while controlling for effects of performance and brain morphology. Behaviorally, children exhibited a numerically smaller alerting effect and significantly larger invalidity (reorienting) and interference (executive control of attention) effects. Neurally, children showed significantly reduced brain activation in a priori defined regions-of-interest in right-sided frontal-midbrain regions during alerting, in the right-sided temporo-parietal junction during reorienting of attention, and in the dorsolateral prefrontal cortex during executive control of attention. In addition, children activated significantly more brain regions outside the a priori defined regions-of-interest, such as the superior frontal gyrus during reorienting and the superior temporal gyrus during executive control of attention. Functional group differences overlapped with structural group differences in gray matter volume in particular within the frontopolar areas. The data suggest that there is a transition from functional yet immature systems supporting attentional functions in children to the more definitive adult networks and that the differences observed may reflect both developmental changes in cognitive strategies and morphology. 相似文献
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Zusammenfassung Auf Grund eingehender Versuche mit Strychninoxyd und seiner Mischung mit Strychnin ließ sich ein Strychnindepotpräparat entwickeln, dessen lange und gleichmäßige Wirkung experimentell nachgewiesen wurde. Eine Kumulation ist bei Injektion therapeutischer Gaben und Einhaltung entsprechender zeitlicher Abstände nicht zu befürchten. Auf die Bedeutung oxydativ-reduktiver Vorgänge sowie des Lebensalters wird hingewiesen (Fieber, Darmkanal, Pädiatrie!)Mit 4 Textabbildungen. 相似文献
80.
Laura J. Hanisch Jun J. Mao Philip R. Gehrman David J. Vaughn James C. Coyne 《Psycho-oncology》2009,18(5):564-567
Objective: An effective and safe alternative treatment to hormone replacement therapy for hot flashes is needed for cancer patients. Interventions targeting the triggering mechanisms of hot flashes hold promise. Increases in core body temperature are a precursor of most hot flashes in women, and similar findings in prostate cancer patients undergoing androgen deprivation therapy would support further research in this area. We present preliminary findings of physiological changes in a prostate cancer patient with frequent hot flashes. Methods: Physiological changes in sternal skin conductance, heart rate, and core body temperature were continuously measured during two 3.5 h laboratory sessions. Perceived characteristics of hot flashes were recorded in a diary. Results: Five hot flashes were reported during laboratory sessions. Severity and bother ratings were low. All hot flashes were accompanied by large increases in sternal skin conductance and moderate increases in heart rate. Core body temperature increased 0.11–0.32°C prior to and fell 0.23–0.44°C following the peak increase in skin conductance. Conclusions: This case study suggests that hot flashes in men may be preceded by increases in core body temperature. Identification of behavioral factors that raise core body temperature may lead to specific treatment strategies to reduce the frequency of hot flashes. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献