mortality/aging
• increase in mortality starting at around 6 months of age due to lymphoid tumors; 60% succumb to tumors with a mean latency of 10 months
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neoplasm
• most lymphoid tumors are derived from T-cell lineage
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• approximately 10% of tumors are derived from very early B-cell lineage
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immune system
• at 4 and 6 weeks of age, thymuses contain about 30% of the cells as normal and at 8 and 10 weeks of age, thymocytes are reduced to 20 and 10%, respectively, of control levels
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• most lymphoid tumors are derived from T-cell lineage
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• premature involution
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• thymus shows progressive accumulation of a T-lineage precursor population arrested at an early stage of maturation
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• progressive decline of mature and immature T-cells
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• thymocytes are reduced to 20 and 10% of control levels at 8 and 10 weeks of age, respectively
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• significant reduction in the relative proportion of immature CD4+CD8+ thymocytes at 10 weeks of age
• by 24 weeks of age, essentially no double-positive cells are evident
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• reduction is seen by 24 weeks of age
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• reduction is seen by 24 weeks of age
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• a proportion of CD4+ thymocytes remaining in the thymus at 24 weeks of age express a lower level of surface CD4 compared to the high levels present in control cells
• majority of CD4+ thymocytes at 24 weeks of age lack coexpression of CD3
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hematopoietic system
• at 4 and 6 weeks of age, thymuses contain about 30% of the cells as normal and at 8 and 10 weeks of age, thymocytes are reduced to 20 and 10%, respectively, of control levels
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• most lymphoid tumors are derived from T-cell lineage
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• premature involution
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• thymus shows progressive accumulation of a T-lineage precursor population arrested at an early stage of maturation
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• progressive decline of mature and immature T-cells
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• thymocytes are reduced to 20 and 10% of control levels at 8 and 10 weeks of age, respectively
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• significant reduction in the relative proportion of immature CD4+CD8+ thymocytes at 10 weeks of age
• by 24 weeks of age, essentially no double-positive cells are evident
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• reduction is seen by 24 weeks of age
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• reduction is seen by 24 weeks of age
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• a proportion of CD4+ thymocytes remaining in the thymus at 24 weeks of age express a lower level of surface CD4 compared to the high levels present in control cells
• majority of CD4+ thymocytes at 24 weeks of age lack coexpression of CD3
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endocrine/exocrine glands
• at 4 and 6 weeks of age, thymuses contain about 30% of the cells as normal and at 8 and 10 weeks of age, thymocytes are reduced to 20 and 10%, respectively, of control levels
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• thymocytes are reduced to 20 and 10% of control levels at 8 and 10 weeks of age, respectively
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• most lymphoid tumors are derived from T-cell lineage
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• premature involution
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