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AN ANALYSIS OF EFFECTS OF FETAL ORDER AND PARENTAL AGE ON RETINOBLASTOMA
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作者 沈福民 赵鹏飞 +1 位作者 陈浩 仉逴 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1990年第1期16-19,共4页
Seventy-eight cases of retinoblastoma (Rb) diagnosed at the Eye ENT Hospital, Shanghai Medical University from 1953 to 1985 were studied. The results of multiple logistic regression analysis and conditional probabilit... Seventy-eight cases of retinoblastoma (Rb) diagnosed at the Eye ENT Hospital, Shanghai Medical University from 1953 to 1985 were studied. The results of multiple logistic regression analysis and conditional probability model showed that high fetal order had a moderate risk (OR=1.28, P<0.05) of developing unilateral Rb. Both unilateral and bilateral cases were independent of parental ages, and no interaction could be found between fetal order and paternal of maternal age; also, the effect of fetal order was not confounded by parental ages. 展开更多
关键词 AN ANALYSIS OF EFFECTS OF FETAL order AND PARENTAL age ON RETINOBLASTOMA
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Effects of tree size and organ age on variations in carbon,nitrogen,and phosphorus stoichiometry in Pinus koraiensis
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作者 Yanjun Wang Guangze Jin Zhili Liu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期155-165,共11页
Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutr... Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains limited.We determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast China.Soil factors were also measured.The results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil factors.At a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree size.At the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric ratios.Our results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual level.It is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for survival.Conversely,nutrient storage strategy in older trees and organ fractions are mainly for steady growth.Our results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations. 展开更多
关键词 Tree size Organ age(or root order) Carbon(C) Nitrogen(N) Phosphorus(P) Pinus koraiensis
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