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We found that, in the mouse visual cortex, action potentials generated in a single layer-2/3 pyramidal (excitatory) neuron can reliably evoke large, constant-latency inhibitory postsynaptic currents in other nearby pyramidal cells. This effect is mediated by axo-axonic ionotropic glutamate receptor-mediated excitation of the nerve terminals of inhibitory interneurons, which connect to the target pyramidal cells. Therefore, individual cortical excitatory neurons can generate inhibition independently from the somatic firing of inhibitory interneurons.  相似文献   
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For the first time, fig mosaic virus (FMV) was detected in common fig (Ficus carica) trees in Shimane, Japan. These trees exhibited mosaic, ringspots, or distortion, accompanied by chlorosis on leaves and yellow spots on fruits. Some of the symptomatic trees were infested with the eriophyid mite Aceria ficus. The virus was detected based on RT-PCR, followed by sequencing. The amplified 300 base-pair fragments shared 83.5–91.5% identity with the corresponding region of RNA-dependent RNA polymerase gene of FMV isolates previously reported in Turkey, Iran, and Italy.  相似文献   
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Macrophage colony-stimulating factor (M-CSF) is a hemopoietic cytokine with a primary role in placental physiology. Gene expression of M-CSF in the bovine endometrium shows a temporal upward trend during early and mid pregnancy. This study determined the plasma M-CSF levels during pregnancy using ELISA. In experiment 1, to investigate the relationship between the concentration of M-CSF in peripheral blood and pregnancy, the plasma M-CSF levels were determined in 125 pregnant and 21 non-pregnant Japanese Black cows. The pregnant animals were divided into nine groups based on the month of pregnancy. An ELISA for bovine M-CSF established previously was used according to the authors' instructions. In experiment 2, the plasma M-CSF level was determined to investigate the temporal changes in its concentration in the peripheral blood during pregnancy. In experiment 1, the plasma M-CSF level varied from month to month during pregnancy; the mean level in the first-month of pregnancy was significantly higher than those in the third and last months of pregnancy and non-pregnancy (P<0.05). In experiment 2, the plasma M-CSF level varied with the day of pregnancy (P<0.05). The mean level of plasma M-CSF decreased gradually until 6 weeks of pregnancy; it appeared to increase during weeks 7-9, then varied with several small peaks until 27 weeks of pregnancy and finally decreased gradually until parturition. These results suggest that the plasma M-CSF level may be related to changes in the uterus and placenta as pregnancy progresses.  相似文献   
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Alpha-Hemoglobin stabilizing protein (AHSP) functions as the erythroid-specific molecular chaperon for alpha-globin. AHSP gene expression has been reported to be downregulated in hematopoietic tissues of animals suffering from prion diseases though the mechanism remains to be clarified. Herein, we demonstrate that MELhipod8 cells, a subclone of murine erythroleukemia (MEL) cells, have prion protein (PrPc) on the cell surface and have highly inducible expression of the AHSP and alpha- and beta-globin genes, resembling the expression pattern of the PrP and AHSP genes in bipotential erythroid- and megakaryocyte-lineage cells followed by erythroid differentiation in normal erythropoiesis. Moreover, MELhipod8 cells exhibit greater effective erythroid differentiation with a population of hemoglobinized normoblast-like cells than that observed for the parental MEL cells. These findings suggest that MELhipod8 cells could provide a mechanism for downregulation of the AHSP gene in prion diseases.  相似文献   
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RNA silencing pathways in filamentous fungi are composed of multiple component proteins and known to be involved in vegetative growth, virulence or sexual reproduction. We found that the tomato wilt fungus, Fusarium oxysporum f. sp. lycopersici (Fol), carries four homologues genes of Qde-2, an argonaute protein gene and one of the main component protein genes in Neurospora crassa. Gene targeting revealed that FoQde-2, one of the Qde-2 homologues in Fol, is involved in virulence to tomato but not in vegetative growth.  相似文献   
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