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151.
We have investigated the expression of cyclins, cyclin dependent kinases (CDK), and CDK inhibitors (CKI) at the mRNA level in a panel of small-cell lung cancer (SCLC) cell lines in vitro and in vivo as xenografts in nude mice. The results showed that the cell lines expressed varying amounts of most cyclin and CDK's but only a few of the cell lines expressed cyclin D1 and/or D2 and some lacked expression of CDK6. Most cell lines expressed mRNA for the CKI's but two cell lines lacked expression of P15INK4B and p16INK4A. The mRNA expression differed for a few of the cell lines regarding cyclin D2 and CDK6 when in vitro and in vivo data were compared. Two of the cell lines that express the retinoblastoma (Rb) protein had no sign of a deregulated Rb pathway but further studies at the protein level are necessary to demonstrate whether these two cell lines should have a normal Rb pathway or whether they will join the majority of cell lines with deregulated Rb pathway. 相似文献
152.
EM Perchellet JB Ladesich Y Chen HS Sin DH Hua SL Kraft JP Perchellet 《Canadian Metallurgical Quarterly》1998,9(6):565-576
Methods of both linkage analysis and association analysis may be model-based or model-free. The former are useful for initial exploratory analysis, the latter for more detailed multivariate genometric analysis. Linkage leads to an association, but that association may be solely intrafamilial. Allelic association may be due to pleiotropy, linkage disequilibrium, meiotic drive, selection, or population stratification. Using non-transmitted parental alleles as controls for alleles transmitted to cases, in conjunction with a McNemar-type test, does not detect association in the absence of linkage. Model-based analyses should use models that approximate the complexity of the disease being studied in order to be both robust and powerful. 相似文献
153.
RJ Dunn CJ Luedecker HS Haugen CH Clegg AG Farr 《Canadian Metallurgical Quarterly》1997,45(1):129-141
We characterized the distribution of CD40 and CD40 ligand (CD40-L) in the adult and developing murine thymus. Before birth, CD40 was almost exclusively localized to scattered foci of medullary cells. By birth there was a dramatic upregulation of CD40 expression by cortical epithelial cells, which was accompanied by a consolidation of medullary epithelial foci. CD40-L+ thymocytes displayed a medullary location. Analysis of mice deficient in CD40-L expression indicated that CD40-L/CD40 interactions were not required for development of the medullary compartment. Overexpression of CD40-L targeted to thymocytes altered thymic architecture, as reflected by a dramatic loss of cortical epithelial cells, expansion of the medullary compartment, and extensive infiltration of the capsule with a mixture of CD3+ cells, B-cells, and macrophages/dendritic cells. Reconstitution of lethally irradiated normal mice with lck CD40-L bone marrow cells also resulted in loss of cortical epithelium and expansion of the medullary compartment. Disruption of the normal pattern of thymic architecture and epithelial differentiation as a consequence of increased intrathymic levels of CD40-L expression points to a role for CD40-L/CD40 interactions in the normal pattern of epithelial compartmentalization/differentiation within the thymic environment. 相似文献
154.
Regional levels of lactate and free fatty acids (FFA) were measured after lateral fluid percussion (FP) brain injury in rats. At 5 min after injury, tissue concentrations of lactate were elevated in the cortices and hippocampi of both ipsilateral and contralateral hemispheres. Whereas lactate levels had returned to normal by about 20 min after injury in the penumbra and contralateral cortices, their elevation persisted in the ipsilateral injured cortex and hippocampus for 24 h after injury. Increases in the levels of FFA (particularly stearic and arachidonic acids) were observed in the cortices and hippocampi of both ipsilateral and contralateral hemispheres at 5 min after injury; these levels returned to normal in only the penumbra and contralateral cortices by 20 min after injury. Increased amounts of palmitic and oleic acids were also found only in the injured left cortex and ipsilateral hippocampus at 20 min or later after injury. In general, these elevations persisted for as long as 6 to 24 h in the injured cortex and for 2.5 to 24 h after injury in the ipsilateral hippocampus. Histologic studies revealed a similar extent of damage in the cortex between 5 min and 24 h after injury, whereas damage in the CA3 region of the ipsilateral hippocampus increased during that period. These findings suggest a role for lactic acid and FFA, two secondary injury factors, in neuronal cell loss after brain injury. 相似文献
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159.
C Grau LK Specht HS Hansen M Overgaard J Overgaard 《Canadian Metallurgical Quarterly》1997,159(8):1104-1108
In a prospective study, the value of the clinical follow-up after treatment for head and neck cancer has been assessed. A total of 407 visits in 377 patients were recorded during a three month period in 1993 at the two major radiotherapy departments in Denmark. The results showed that 61% of follow-up visits included one or more problems either related to treatment morbidity or tumour recurrence. About 50% of all visits included treatment related normal tissue problems, and 30% had problems that required intervention. Although the majority of problems occurred within a few years after treatment, 47% of patients at three to four years observation time still had one or more problems. A total of 34 new tumour recurrences were found in the period, and of these 11 (32%) were asymptomatic. It is concluded that head and neck cancer patients have both tumour and normal tissue problems several years after the end of treatment. Since effective salvage treatment improves local control significantly, early detection of possible recurrence is important. A follow-up period of four to five years is recommended-preferably by qualified experts in the management of both recurrent disease and treatment morbidity. 相似文献
160.
A 2-year-old female Burmese cat was referred to the University Hospital of Companion Animals of Utrecht University because of periodic muscle weakness and cervical ventroflexion. Laboratory examinations revealed hypokalemia. The combination of breed, clinical signs and hypokalemia warranted the diagnosis of 'periodic hypokalemic myopathy', a homozygote recessive hereditary disease in Burmese cats. Potassium supplementation resulted in complete disappearance of the signs. Possible causes of hypokalemia in the cat are discussed. 相似文献