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The beagle dog with hereditary primary open-angle glaucoma, unlike other animal models of human glaucoma, possesses a slowly progressive, sustained elevation of intraocular pressure. The effects of this insidious elevation in intraocular pressure on the axons of the optic nerves of three beagles at early stages of glaucoma and two beagles with advanced signs of glaucoma were compared to the optic nerves of four age-matched normal dogs. Plastic embedded optic nerve cross-sections (1 micron) 1 mm posterior to the lamina cribrosa were osmicated and stained with Toluidine Blue. Axons from 0.2 to > 2.0 microns in diameter were counted and measured in 16 cross-sectional regions of equal size within the whole optic nerve using a computerized image analysis system. The mean optic nerve axon diameters in the normal, early glaucomatous, and advanced glaucomatous dogs were 1.53, 1.25 and 1.13 microns respectively. The average total optic nerve axon count in the normal dogs was 148,303. Approximately 16% of the total axonal fibers were counted in each nerve. The counts of optic nerve axons 2.0 microns or greater in diameter were reduced by up to 60% in the central regions of the optic nerves of affected beagles. The large diameter axons of the peripheral optic nerve of the beagle dogs with glaucoma were more resistant to the elevated intraocular pressure. The counts of axons > 0.6 to 0.8 micron in diameter were significantly increased in glaucomatous beagles.  相似文献   
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Thirty children, aged between five and 15 years, were randomly allocated to receive postoperative analgesia from continuous morphine infusion (CMI) or patient controlled analgesia (PCA), also using morphine. The children's morphine consumption, respiratory rates, oxygen saturations and observation points during which they were sleeping were recorded during two periods, one on the day of operation and one the following day. The median dose of morphine consumed by the children using PCA was significantly larger than that consumed by the children having continuous infusions. Children aged between nine and 15 years using PCA had significantly lower minimum respiratory rates and minimum oxygen saturations than similarly aged children receiving continuous infusions. There was no significant difference between the PCA and CMI groups in the number of observation times that the children were asleep or in the minimum respiratory rates and minimum oxygen saturations in the awake and sleeping children.  相似文献   
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A review contemplates as a whole the problem of regulation of the cellular volume. The first part of the review considers the influences inducing alterations in the cells volume on account of changes in the tonicity of extracellular milieu and cytoplasm. The review elucidates the ways of implementing the fast and slow regulatory volume increase as well as decrease (RVI, RVD). The volume increase seems to enhance cells' proliferative ability due to activation of ions transport. The volume decrease needs further investigations. The last chapter of the review considers pathophysiological significance of the volume regulation in hyponatremia, diabetes, neutrophil activation.  相似文献   
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Mutations within microsatellite sequences, consisting of additions or deletions of repeat units, are known as the replication/repair error positive (RER+) phenotype or micorsatellite instability (MI). Microsatellite instability has been demonstrated in hereditary and sporadic colorectal carcinomas and is usually observed in noncoding regions of genomic DNA. However, relatively few coding region targets of MI have been identified thus far. Using PCR, we amplified regions encompassing (A)8 and (C)8 microsatellite tracts within hMSH3 and hMSH6 from 31 RER+ sporadic colorectal tumors, 8 hereditary colon cancers, 23 RER+ gastric carcinomas, and 32 RER- gastric tumors. Mutations were found in 11 (36%) of 31 sporadic colon carcinomas, 4 (50%) of 8 hereditary colorectal cancers, and 5 (22%) of 23 RER+ gastric carcinomas, but in only 2 (6%) of 32 RER- gastric carcinomas. These frameshift mutations cause premature stop codons downstream that are predicted to abolish normal protein function. Our results and those of others suggest that DNA mismatch repair genes, such as hMSH3 and hMSH6, are targets for the mutagenic activity of upstream mismatch repair gene mutations and that this enhanced genomic instability may accelerate the accumulation of mutations in RER+ tumors.  相似文献   
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The patient is a 12-year-old boy with acute mixed lineage leukemia (AMLL) and with a rare karyotype of trisomy 6. He was referred to our hospital with gingival swelling, bleeding at the conjunctiva and huge hepatosplenomegaly. Complete blood count revealed leukocytosis with 79% blasts, anemia and thrombocytopenia. Bone marrow examination revealed 82.5% blasts which were morphologically judged as M1 according to the French-American-British classification. Immunophenotyping of leukemic cells showed the presence of CD2, CD7, CD19 and CD13 antigens, suggesting the diagnosis of AMLL. Cytogenetic analysis revealed a single abnormal karyotype of 47,XY,+6,add(15)(q22) which was successfully detected by fluorescence in situ hybridization (FISH) with the probe mapping at the alpha-satellite region of chromosome 6. Although the patient was treated with several chemotherapy regimens, he could not achieve complete remission and he died of progressive disease 11 months after admission. Fluorescence in situ hybridization analysis was very informative in assessing the residual leukemic cells in interphase during his clinical course.  相似文献   
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