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651.
Females of several species of macaques form cohesive matrilineal units in which all members share a collective status. The
relationship between rank and kinship inMacaca radiata has not previously been studied. Analysis of observations of social interactions in a large and stable captive group ofM. radiata and longitudinal study of kinship and reproductive success indicate that with few exceptions a matrilineal dominance hierarchy
exists in that group. Four young, upwardly mobile females are responsible for the exceptions. Contrary to the pattern noted
in other species of macaques, several adult females outrank their daughters. Old age and deteriorating physical condition
of mothers appear to be associated with mother-daughter rank reversals. The age and lineage size of females when they entered
the group have had a lasting impact. Females who entered the group as adults have achieved higher rank and greater reproductive
success than females who entered the group as juveniles without relatives.
This research was conducted at the California Primate Research Center in Davis, supported by USPHS grant RR00169. 相似文献
652.
Nucleoside analogs used in antiretroviral treatment have been associated with mitochondrial toxicity. The polymerase-γ hypothesis states that this toxicity stems from the analogs'' inhibition of the mitochondrial DNA polymerase (polymerase-γ) leading to mitochondrial DNA (mtDNA) depletion. We have constructed a computational model of the interaction of polymerase-γ with activated nucleoside and nucleotide analog drugs, based on experimentally measured reaction rates and base excision rates, together with the mtDNA genome size, the human mtDNA sequence, and mitochondrial dNTP concentrations. The model predicts an approximately 1000-fold difference in the activated drug concentration required for a 50% probability of mtDNA strand termination between the activated di-deoxy analogs d4T, ddC, and ddI (activated to ddA) and the activated forms of the analogs 3TC, TDF, AZT, FTC, and ABC. These predictions are supported by experimental and clinical data showing significantly greater mtDNA depletion in cell culture and patient samples caused by the di-deoxy analog drugs. For zidovudine (AZT) we calculated a very low mtDNA replication termination probability, in contrast to its reported mitochondrial toxicity in vitro and clinically. Therefore AZT mitochondrial toxicity is likely due to a mechanism that does not involve strand termination of mtDNA replication. 相似文献
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A review of the first 100 years of studies on fungi (including lichens) at The New York Botanical Garden is presented. 相似文献