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151.
In freely moving rats, effects of unilateral haloperidol injection into the substantia nigra were monitored with in vivo voltammetry in the bilateral striata. The electrochemical responses at 120 mV versus Ag-AgCl, reflecting mainly a level of 3,4-dihydroxyphenylacetic acid (DOPAC), increased both in the striata within 1.5 h after 5 μg of haloperidol treatment. In the experiments of high-performance liquid chromatography with electrochemical detection, the ratio of DOPAC to dopamine in the striata significantly increased at 2.75 h after drug treatment. These data support the idea that unilateral injection of haloperidol into the substantia nigra in freely moving rats increases dopamine turnover in the bilateral striata.  相似文献   
152.
153.
The measurement of IgE and IgG4 antibodies against egg white, milk, soybean and Dermatophagoides farinae was performed by FAST (fluorescence allergosorbent test) using 21 serum samples obtained from non-allergic children and 160 serum samples from atopic children with bronchial asthma and/or atopic dermatitis. Their antibody levels were evaluated for any association with disease severity and for clinical significance in establishing diagnosis. It was found that children with bronchial asthma showed lower levels of IgE antibodies against egg white, milk and soybean and higher levels of IgE antibodies against Dermatophagoides farinae compared with those of children with atopic dermatitis, while both groups showed higher levels of egg white and milk-specific IgG4 antibodies compared with non-allergic children. These IgE and IgG4 antibody levels revealed a tendency to correlate with disease severity in patients with atopic dermatitis, while this was not observed in patients with bronchial asthma. The contribution percentages of IgG4 antibody determination, together with IgE antibody determination, in retrieving causal allergens were 71% for egg white, 70% for milk and 48% for soybean allergy, implying their diagnostic value in establishing clinical diagnosis.  相似文献   
154.
We report on a 9-year-old boy with radioulnar synostosis, short stature, microcephaly, soliosis, and mental retardation. We propose that he has a new syndrome. © 1995 Wiley-Liss, Inc.  相似文献   
155.
Free radicals are involved in the pathogenesis and/or progression of Parkinson's disease (PD). Several ergot derivative dopamine (DA) agonists have been reported to scavenge free radicals in vitro and to show a neuroprotective effect in vivo. We investigated the in vitro free radical scavenging and antioxidant activities of cabergoline, a long-acting ergot DA agonist, as well as its ability to activate glutathione (GSH), catalase (Cat) and superoxide dismutase (SOD) activating effects and its in vivo neuroprotective properties against 6-hydroxydopamine (6-OHDA) intracerebroventricularly (i.c.v.) in mice. The striatal DA turnover induced by i.c.v. injection of 6-OHDA was completely normalized by pretreatment with cabergoline. Moreover, cabergoline scavenged free radicals in vitro and significantly reduced lipid peroxidation in vitro and in vivo. Furthermore, daily administration of cabergoline to mice significantly increased striatal GSH levels by activation of RNA expressions of GSH-related enzymes, although striatal Cat and SOD activities did not change. In addition, our present results suggest that repeated administration of cabergoline attenuates both 6-OHDA-induced nigrostriatal DAergic dysfunction and DA neuronal cell death, since cabergoline also had a neuroprotective effect in the immunohistochemical experiment. In conclusion, our findings indicate that the multiple antioxidant mechanisms of cabergoline, such as activation of the GSH system and the direct free radical scavenging activity, may explain the neuroprotective effect of this ergot DA agonist.  相似文献   
156.
Cytoplasmic concentrations of Ca2+ ([Ca2+]i) and Mg2+ ([Mg2+]i) were measured with fluorescent indicators in CCL39 cells, a cell line established from Chinese hamster lung fibroblasts, transfected with complementary deoxyribonucleic acid (cDNA) of the Na+-Ca2+ exchanger isolated either from canine heart (NCX1) or from rat brain (NCX3). Raising extracellular [Mg2+] to 10 mM increased Mg2+ influx and the resultant change in [Mg2+]i (delta[Mg2+]i) was monitored with furaptra under Ca2+-free conditions. In control (vector-transfected) cells, delta[Mg2+]i at 45 min was similar with or without extracellular Na+ (130 mM or 0 mM) and when [Na+]i was raised by 1 mM ouabain treatment. delta[Mg2+]i in NCX1-transfected cells was attenuated significantly in the presence of 130 mM Na+, but became comparable to (or slightly larger than) that in control cells on either removal of extracellular Na+ or treatment with 1 mM ouabain. Cells expressing NCX3 showed an intermediate dependence of delta[Mg2+]i on Na+, probably reflecting a lower degree of expression of the exchanger protein. Extracellular Na+-dependent changes in [Ca2+]i (measured with fura-2 in the presence of extracellular Ca2+ and 10 microM ionomycin, a Ca2+ ionophore) were minimal in control cells, marked in the NCX1-transfected cells and intermediate in the NCX3-transfected cells. These results suggest that the Na+-Ca2+ exchanger (either NCX1 or NCX3) can transport Mg2+ and may play a role in the extrusion of magnesium from cells.  相似文献   
157.
A large area and highly sensitive thermoluminescent (TL) sheet film was used for two-dimensional dose distribution measurements at millimetre distances from a 103Pd interstitial brachytherapy source. The TL film is made of Teflon homogeneously mixed with small particles of thermoluminescent material (BaSO4: Eu doped). This TL sheet (5 cm x 5 cm) was used to determine the relative dosimetric characteristics (i.e., radial dose function, 2D and 1D anisotropy functions, as defined by the updated AAPM Task Group No 43 report) of the model 200 103Pd source that emits low energy photons (21 keV). The two-dimensional dosimetry data were obtained for distances from the source surface to 15 mm. The radial dose function measured with the TL sheet is in reasonable agreement within 11% with the values recommended in the updated AAPM TG-43 report. All the measured 2D dose distributions showed limited symmetry about the source axes. The differences between the 1D anisotropy function values measured with the TL sheet and the data recommended in the updated AAPM TG-43 report were 10% at 5 mm and 7.5% at 10 mm, respectively, for the model 200 103Pd seed. Our experiments have demonstrated that it is feasible to use the TL sheet as a dosimeter in the determination of the dosimetric characteristics in the immediate vicinity of interstitial brachytherapy sources emitting low energy photons.  相似文献   
158.
Direct visualization of crystal growth in poly(L ‐lactide) thin films was carried out by using a temperature‐controlled atomic force microscopy (AFM). At the initial stage of crystallization, edge‐on lamellar crystals have nucleated and elongated. Subsequently, the edge‐on lamellar crystals showed S‐shaped morphology and changed their orientation from edge‐on manner to flat‐on one. The curvature of edge‐on lamellar crystal has been discussed in terms of inclination and distortion of polymer chains in the crystal. In addition, mechanism on the formation of flat‐on crystal from edge‐on lamellae was proposed as derivative growth on the basis of in situ AFM observation of crystal growth and enzymatic degradation.

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159.
It has been reported that neurons in the orbitofrontal cortex (OFC) respond to emotionally significant events such as reward-predicting cues and/or the reward itself. The responses to reward-predicting cues are considered to carry the information of the predicted reward. However, few studies have focused on the relationship of the neuronal activity during a cue period with that during a reward period. We can infer that the cue responses of OFC neurons are correlated to the reward responses if they carry the information of the predicted reward. In this study, we focused on neurons that showed responses during both the cue and reward periods, and compared the response characteristics between these periods. We found 94 of 369 OFC neurons showed significant responses during both the cue and reward periods, and 43 of which preserved their selectivity between these periods. Furthermore, population analysis showed that stronger cue responses corresponded to stronger reward responses, and stronger reward responses corresponded to stronger cue responses. These results suggest that individual neurons in the OFC associate visual information with reward information, and contribute to the prediction of future rewards by forming reward representations.  相似文献   
160.
Since our previous experiments suggested that glycosylation-inhibiting factor (GIF) is a phosphorylated derivative of a phospholipase inhibitory protein, we determined whether other well-known phospholipase inhibitors may have similar biological activities. The results showed that phospholipase A2 (PLA2) inhibitors, such as recombinant human lipocortin I and ONO-RS-082, could switch T cell hybridoma 12H5 cells from the formation of glycosylated IgE-binding factors (IgE-BF) to the formation of unglycosylated IgE-BF, whereas neomycin, a phospholipase C inhibitor, failed to affect the nature of IgE-BF formed by the cells. The minimum concentrations of lipocortin I and ONO-RS-082 required for switching the 12H5 cells to the formation of unglycosylated IgE-BF were comparable to or less than IC50 of the inhibitors for PLA2. The ability of partially purified GIF to switch the 12H5 cells to the formation of unglycosylated IgE-BF was markedly enhanced by treatment of the preparation with alkaline phosphatase. It was also found that lipocortin I and ONO-RS-082, but not neomycin, facilitated the generation of GIF-producing T cells. When spleen cells of ovalbumin (OVA)-primed BDF1 mice were stimulated with homologous antigen and the activated T cells were propagated by recombinant IL-2 in the presence of GIF, lipocortin I, or ONO-RS-082, T cells obtained in the cultures constitutively produced their own GIF. Antigenic stimulation of the T cells induced the formation of unglycosylated IgE-BF and GIF with an affinity for OVA.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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