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71.
All-night sleep EEG and auditory evoked responses (AERs) were recorded in 8 children whose ages ranged from 27 to 60 months. EEG intensity was measured by means of a Drohocki-type integrator. Two measures of evoked response amplitude were calculated: the peak-to-peak amplitude of the P2N2 component, and a multiple-component amplitude measure of the first 500 msec of the response. Both amplitude measurements were found to correlate well with each other. Changes in EEG intensity between subjects were not correlated with changes in AER amplitude, but a number of correlations between AER amplitude and EEG intensity were found within individual subjects. Further analysis suggested the latter finding might be a result of the presence of “unaveraged’EEG in individual AER plots. It is concluded that little correlation exists between AER amplitude and EEG intensity in children during sleep.  相似文献   
72.
Sixty-six bipolar I lithium clinic patients were studied for a history of psychotic symptoms at some time during the course of their illness. Agreement between different sources of information was calculated, and the patient population was divided into psychotic and non-psychotic subgroups. Probability of remaining well on lithium for the different subgroups was analyzed by the life table method. Psychosis during mania appeared to be associated with especially good early lithium prophylaxis.  相似文献   
73.
The biodegradation of different porous β-whitlockite materials are studied by in vivo experiments, radiographie follow-ups and light microscopy observations. The materials were implanted in rabbit tibiae for 16 mnth. Micropores play an important role in the biodegradation rate. The resorbing materials evoke an inflammation with plasma cells. The resorption starts in the medulla, and the phagocytosed particles are removed to the lymph nodes. Normal bone function can be restored after all the implant material is resulted.  相似文献   
74.
Autocrine motility factor (AMF) is one of the motility cytokines regulating tumor cell migration, therefore identification of the signaling pathway coupled with it has critical importance. Previous studies revealed several elements of this pathway predominated by lipoxygenase-PKC activations but the role for tyrosine kinases remained questionable. Motility cytokines frequently have mitogenic effect as well, producing activation of overlapping signaling pathways therefore we have used B16a melanoma cells as models where AMF has exclusive motility effect. Our studies revealed that in B16a cells AMF initiated rapid (1–5 min) activation of the protein tyrosine kinase (PTK) cascade inducing phosphorylation of 179, 125, 95 and 40/37 kD proteins which was mediated by upstream cyclo- and lipoxygenases. The phosphorylated proteins were localized to the cortical actin-stress fiber attachment zones in situ by confocal microscopy. On the other hand, AMF receptor activation induced significant decrease in overall serine-phosphorylation level of cellular proteins accompanied by serine phosphorylation of 200, 90, 78 and 65 kd proteins. The decrease in serine phosphorylation was independent of PTKs, PKC as well as cyclo- and lipoxygenases. However, AMF induced robust translocation of PKCα to the stress fibers and cortical actin suggesting a critical role for this kinase in the generation of the motility signal. Based on the significant decrease in serine phosphorylation after AMF stimulus in B16a cells we postulated the involvement of putative serine/threonine phosphatase(s) upstream lipoxygenase and activation of the protein tyrosine kinase cascade downstream cyclo- and lipoxygenase(s) in the previously identified autocrine motility signal. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
75.
While IL-12 administration induces tumor regression through stimulating T cells in tumor-bearing mice, this IL-12 effect is observed in some but not all tumor models. The present study aimed to compare IL-12 responsiveness of T cells from tumor-bearing mice in IL-12-responsive (CSA1M and OV-HM) and -unresponsive (Meth A) tumor models. Tumor regression in IL-12-responsive tumor models required the participation of T cells, but not of NK1.1(+) cells. Because a NK1.1(+) cell population was the major producer of IFN-gamma, comparable levels of IFN-gamma production were induced in IL-12-responsive and -unresponsive tumor-bearing mice. This indicates that the amount of IFN-gamma produced in tumor-bearing individuals does not correlate with the anti-tumor efficacy of IL-12. In contrast, IL-12 responsiveness of T cells differed between the responsive and unresponsive models: purified T cells from CSA1M/OV-HM-bearing or Meth A-bearing mice exhibited high or low IL-12 responsiveness respectively, when evaluated by the amounts of IFN-gamma produced in response to IL-12. T cells from CSA1M- or OV-HM-bearing but not from Meth A-bearing mice exhibited enhanced levels of mRNA for the IL-12 receptor (IL-12R). These results indicate that a fundamental difference exists in IL-12 responsiveness of T cells between IL-12-responsive and -unresponsive tumor models, and that such a difference is associated with the expression of IL-12R on T cells.  相似文献   
76.
Regional cerebral blood flow is measured by monitoring the clearance from the brain of the gamma emitting radioisotope 133Xe following an intracarotid artery bolus injection. On-line data analysis, which is performed on a PDP 1230 digital computer, involves exponential stripping to isolate grey and white matter flows and integration of the clearance curves to infinity to enable the mean flow to be calculated. The data is displayed in real time and stored on the PDP 12 Linc tapes as a permanent record.  相似文献   
77.
Voltage- and Ca(2+)-dependent K(+) channels in the membrane of both T and B lymphocytes are important for the cellular immune response. In the current issue of the European Journal of Immunology, Reich et al. demonstrate that selective blockade of the intermediate-conductance Ca(2+)-activated K(+) channel (the IK channel encoded by the KCNN4 gene) prevents cytokine production in the spinal chord and ameliorates the development of EAE caused by injection of myelin oligodendrocyte glycoprotein (MOG)(35-55) in mice. These data renew the focus on the IK channel as a potential target for the development of new immune-suppressant drugs for the treatment of autoimmune diseases.  相似文献   
78.
We report on a 19-month-old girl with a derivative chromosome 9 and a recombinant chromosome 12 resulting from a maternal balanced complex rearrangement involving chromosomes 8, 9, and 12. The karyotype of the phenotypically normal mother was 46,XX,t(8;12) (9;12) (8qter→8p23::12q12→12q15::9q32→9qter;9pter→9q32::12q15→12qter;12pter→12q12::8p23→8pter). The child's karyotype was 46,XX,?9,?12, +der(9) (9pter→9q32::12q15→12qter),+rec(12) (12pter→12q15::9q32→9qter) mat. The child had severe growth retardation, minor anomalies including trigonocephaly, hypertelorism, broad nasal root, apparently low-set and posteriorly angulated ears, triangular face, pectus carinatum, clinodactyly of fifth fingers, and almost normal psychomotor development. To the best of our knowledge, there have been only 3 previous reports of recombination derived from parental complex chromosome rearrangements. In the recombination products, the chromosomes were apparently balanced and the offspring had no clinical abnormalities. The present case exhibited abnormalities and may have a submicroscopic aberration of 12q arising from crossing over during maternal meiotic pairing, although her chromosomes appeared to be balanced. © 1993 Wiley-Liss, Inc.  相似文献   
79.
Adenoviruses 12 and 31, but not Ad18, agglutinate rat blood cells at high titer, providing suitable blood cells be available and a prolonged contact period of virus with the erythrocytes is allowed. Purified virus particles show direct, and virus-free supernatants show direct and indirect, hemagglutination, ie, enhancement of HA by heterologous antiserum. Hemagglutination inhibition with rabbit antisera shows cross-reactions between Ad12 and Ad31 with titers 4--32 times lower than with homologous antigens; Ad18 antisera react with antigens from both of the other serotypes. No cross-reactions were seen with antisera from other adenoviruses. This suggests an antigenic relationship of the three viruses of subgroup IV in their fiber antigen gamma, in addition to the known relation in the hexon (epsilon), which is apparent in cross-neutralization.  相似文献   
80.
Ventricular cells of adult mice were prepared by an enzyme digestion procedure. Single channel currents were recorded by a conventional patch clamp technique from cell attached patches. Voltage steps from the holding potential of –80 mV to test potentials between –35 and +50 mV caused openings of two types of outward currents through single channels with the conductances of 27 and 12 pS, respectively. The averaged currents reveal transient time courses for both channel types. The current-voltage relations of both single channel currents were linear over the tested voltage range and intersected the voltage axis at –70 mV. This indicates that both single channel currents are mainly carried by potassium ions. All open and closed times were found to be voltage independent. The 27 pS channel had a mean open time of 3.9±1.0 ms (n=8). The closed time consisted of two components with 1 = 2.1 ± 0.2 ms and 2 = 50 ± 19 ms (n=8). The 12 pS channel had a mean open time of 34.0±5.2 ms (n=3) and the two components of the mean closed time have been calculated as 1 = 8.3 ± 2.1 ms and 2 = 120 ± 50 ms (n=3; all mean ±SD).  相似文献   
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