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991.
Protein kinases play an important role in controlling synaptic strength at excitatory synapses on CA1 pyramidal cells. We examined the effects of activating cAMP-dependent protein kinase or protein kinase C (PKC) on the frequency and amplitude of miniature excitatory postsynaptic currents (mEPSCs) with perforated patch recording techniques. Both forskolin and phorbol-12,13-dibutryate (PDBu) caused a large increase in mEPSC frequency, but only PDBu increased mEPSC amplitude, an effect that was not observed when standard whole cell recording was performed. These results support biochemical observations indicating that PKC, similar to calcium/calmodulin-dependent protein kinase II, has an important role in controlling synaptic strength via modulation of AMPA receptor function, potentially through the direct phosphorylation of the GluR1 subunit.  相似文献   
992.
The author, the fifth superintendent of Alabama's Bryce Hospital since the Wyatt v. Stickney order was issued in 1972, discusses the major problems faced by an administrator in complying with the court-set standards. They relate to qualified mental health professionals, staffing ratios, staff attitudes, individualized treatment plans, and the hospital's negative image. He also discusses the role of the human rights committee and the hospital's goal of providing treatment of sufficient quality that the court order will be lifted.  相似文献   
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We have mapped the chromosomal locations of three human nuclear genes for putative components of the apparatus of mitochondrial gene expression, using a combination of in situ hybridization and interspecies hybrid mapping. The genes RPMS12 (mitoribosomal protein S12, a conserved protein component of the mitoribosomal accuracy center), TUFM (mitochondrial elongation factor EF-Tu), and AFG3L1 (similar to the yeast genes Afg3 and Rca1 involved in the turnover of mistranslated or misfolded mtDNA-encoded polypeptides) were initially characterized by a combination of database sequence analysis, PCR, cloning, and DNA sequencing. RPMS12 maps to chromosome 19q13.1, close to the previously mapped gene for autosomal dominant hearing loss DFNA4. The TUFM gene is located on chromosome 16p11.2, with a putative pseudogene or variant (TUFML) located very close to the centromere of chromosome 17. AFG3L1 is located on chromosome 16q24, very close to the telomere. By virtue of their inferred functions in mitochondria, these genes should be regarded as candidates of disorders sharing features with mitochondrial disease syndromes, such as sensorineural deafness, diabetes, and retinopathy.  相似文献   
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Mirror fixation     
A mirror is the ideal fixation device for an ophthalmoscopic examination: it is the essense of simplicity, and there is nothing the patient would rather watch than himself.  相似文献   
998.
The influence of ATP and AMP injected into the lateral cerebral ventricle in doses of 50, 100 and 200 mug on behavior in rats was studied. ATP in the doses administered had no effect on behavior of rats. AMP in these doses enhanced motor activity of the rats. Chemical sympathectomy by intracerebral injection of 6-hydroxy-dopamine did not affect the action of either of the compounds on behavior of rats. AMP potentiated the action of intracerbrally administered noradrenaline on behavior of the animals.  相似文献   
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