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21.
Cortex-restricted disruption of NMDAR1 impairs neuronal patterns in the barrel cortex 总被引:14,自引:0,他引:14
Iwasato T Datwani A Wolf AM Nishiyama H Taguchi Y Tonegawa S Knöpfel T Erzurumlu RS Itohara S 《Nature》2000,406(6797):726-731
In the rodent primary somatosensory cortex, the configuration of whiskers and sinus hairs on the snout and of receptor-dense zones on the paws is topographically represented as discrete modules of layer IV granule cells (barrels) and thalamocortical afferent terminals. The role of neural activity, particularly activity mediated by NMDARs (N-methyl-D-aspartate receptors), in patterning of the somatosensory cortex has been a subject of debate. We have generated mice in which deletion of the NMDAR1 (NR1) gene is restricted to excitatory cortical neurons, and here we show that sensory periphery-related patterns develop normally in the brainstem and thalamic somatosensory relay stations of these mice. In the somatosensory cortex, thalamocortical afferents corresponding to large whiskers form patterns and display critical period plasticity, but their patterning is not as distinct as that seen in the cortex of normal mice. Other thalamocortical patterns corresponding to sinus hairs and digits are mostly absent. The cellular aggregates known as barrels and barrel boundaries do not develop even at sites where thalamocortical afferents cluster. Our findings indicate that cortical NMDARs are essential for the aggregation of layer IV cells into barrels and for development of the full complement of thalamocortical patterns. 相似文献
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The direct effect of serotonin and antiserotonin agents on adrenal steroid biosynthesis was studied in isolated adrenal cells derived from patients with Cushing's syndrome. The results indicate that serotonin increases corticosterone production, while the serotonin antagonists cyproheptadine and methysergide depress adrenal steroid - particularly cortisol and aldosterone - biosynthesis. 相似文献
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Stimulation of the nucleus accumbens evokes a potent inhibition in neurons of the ventral tegmental area. GABA is likely to act as a transmitter in this descending inhibitory system. 相似文献
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Probabilistic feature models (PFMs) can be used to explain binary rater judgements about the associations between two types of elements (e.g., objects and attributes) on the basis of binary latent features. In particular, to explain observed object-attribute associations PFMs assume that respondents classify both objects and attributes with respect to a, usually small, number of binary latent features, and that the observed object-attribute association is derived as a specific mapping of these classifications. Standard PFMs assume that the object-attribute association probability is the same according to all respondents, and that all observations are statistically independent. As both assumptions may be unrealistic, a multilevel latent class extension of PFMs is proposed which allows objects and/or attribute parameters to be different across latent rater classes, and which allows to model dependencies between associations with a common object (attribute) by assuming that the link between features and objects (attributes) is fixed across judgements. Formal relationships with existing multilevel latent class models for binary three-way data are described. As an illustration, the models are used to study rater differences in product perception and to investigate individual differences in the situational determinants of anger-related behavior. 相似文献
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Zusammenfassung Die Untersuchung der Carotinoide aus den Äzidien des RostpilzesGymnosporangium juniperi-virginianae Schw. ergab das Vorliegen von 66,5%-Carotin und 33,5%-Carotin (Durchschnittswerte). Diese Werte stimmen mit denjenigen anderer Autoren für Teleuto-Stadium und Pyknidenform überein. Art und Mengenverhältnis der Carotinoide in drei Stadien vonGymnosporangium juniperi-virginianae Schw. (auf verschiedenen Wirtspflanzen) sind daher ungefähr identisch. 相似文献
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P. L. Wolf J. P. Horwitz M. S. Pak Janice Vazquez Elisabeth Von der Muehll 《Cellular and molecular life sciences : CMLS》1967,23(12):1012-1013
Zusammenfassung Eine auffallende Zunahme von -Galactosidase kommt im lymphoetischen Säuger-Gewebe im Zusammenhang mit der immunologischen Auflösung dieses Systems vor. Die hernach auftretende Proliferation retikulärer Zellen steht im Zusammenhang mit der Regeneration dieses Organs. Diese Zellen enthalten eine reichliche Anzahl lysosomatischer Enzyme (z.B. -Galactosidase).
This investigation was supported in part by Public Health Service Research Grants Nos. Ca 02624 and CA 02903 from the National Cancer Institute and in part by an institutional grant to the Detroit Institute of Cancer Research Division of the Michigan Cancer Foundation from the United Foundation of Greater Detroit, and Detroit General Hospital Research Corporation. Newaygo County Cancer Association. We wish to express our gratitude for stenographic assistance to Mrs.Connie Malucusky and MissPatricia Warzocha. 相似文献
This investigation was supported in part by Public Health Service Research Grants Nos. Ca 02624 and CA 02903 from the National Cancer Institute and in part by an institutional grant to the Detroit Institute of Cancer Research Division of the Michigan Cancer Foundation from the United Foundation of Greater Detroit, and Detroit General Hospital Research Corporation. Newaygo County Cancer Association. We wish to express our gratitude for stenographic assistance to Mrs.Connie Malucusky and MissPatricia Warzocha. 相似文献