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641.
Inoculation of New World primates with the human immunodeficiency virus   总被引:1,自引:0,他引:1  
The susceptibility of common marmosets and cotton-top tamarins to infection by HIV-2 in vivo was tested. One year and 19 months, respectively, post-inoculation, sera taken from three of four animals from each species are reactive for HIV-2 antibodies and HIV-specific nucleotide sequences were demonstrated in short-term cultures of PBL from two cotton-top tamarins. The animals remain in good health.  相似文献   
642.
Among nonhuman primates the composition of social groups influences the interactions of group members. We assessed the effects of acute changes in social composition on behavior among 15 adult male vervet monkeys (Cercopithecus aethiops sabaeus). Subjects were observed in their basal social groups which comprised 3 adult males, 2–4 adult females, and offspring; and in two subgroups consisting of either two or three adult males. Agonism and vigilance increased in smaller groups relative to basal conditions, while subjects in two-male groups displayed more aggression than those in three-male groups. These findings suggest that, among male vervet monkeys, acute disruption of stable social groups increases aggressive behavior, and that the amount of agonism is influenced by the composition of the consequent subgroups. © 1992 Wiley-Liss, Inc.  相似文献   
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Remarkably little attention has been focused on the physiological ecology of free-ranging primates. Yet without such information, it may prove difficult to advance our understanding of factors influencing the dietary behavior of wild primates much beyond its present state. Mantled howlers (Alouatta palliata) have been studied in terms of some features of physiological ecology. Results of this work have helped to clarify some factors influencing howler and other primate food choices in the natural environment and have called into question various assumptions about leaf-eating primates. For example, though howlers eat considerable foliage, they do not exhibit a lower than predicted basal metabolic rate, nor do available data suggest that secondary compounds strongly influence howler food selection. Comparison of howlers with members of the Colobinae reveals some differences in features of their respective energetic and digestive physiology and raises timely issues for future research.  相似文献   
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Social instability can adversely affect endocrine, immune and health outcomes, and recent evidence suggests that the sympathetic nervous system (SNS) might mediate these effects. We conducted two studies with adult male rhesus monkeys (Macaca mulatta) to understand how social conditions affect measures of SNS activity and immune function. In Experiment 1, animals were socialized in stable social conditions, then were switched to unstable (stressful) social conditions, then were returned to stable conditions. Analysis revealed quadratic effects for measures of behaviour, urinary metabolites of epinephrine and norepinephrine, and expression of immune response genes: as expected, social instability adversely impacted most measures, and the effects remediated upon re-imposition of stable conditions. Cortisol levels were unaffected. In Experiment 2, we used the sympathomimetic drug methamphetamine to challenge the SNS; animals also underwent socialization in stable or unstable groups. Surprisingly, while methamphetamine elevated plasma catecholamines, responses in lymph nodes tracked the social, and not the drug, condition: social instability upregulated the density of SNS fibres in lymph nodes and downregulated Type I interferon gene expression. Together, these results indicate that the SNS is extremely sensitive to social conditions; full understanding of the adverse effects of social instability on health should therefore incorporate measures of this health-relevant system.  相似文献   
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This study explores the relations between captive and noncaptive (literature-reported wild) adult weights in 53 anthropoid primate species. Based on recent studies of variation in growth among wild populations, it is expected that captive and wild weights are highly correlated. In addition, the lack of a relation between species size and captive and wild weights is anticipated. Differences between wild and captive weights are investigated. Correlations between captive and wild weights are high. Within groups of closely related species, correlations can be expected to average r = .95 for both males and females. At low taxonomic levels (within genera), correlations are not generally as high. However, captive and noncaptive intrageneric correlations are comparable to intrageneric correlations based solely on wild weights reported by different literature sources. Size appears to be unrelated to differences in captive and wild weights. Species that appear to be at elevated risk of obesity are identified. This analysis finds that deviations between captive and wild weights are positively related to growth duration (measured for captive primates). This finding implies that, in long-growing species, wild weights may underestimate asymptotic size. Hypotheses explaining this phenomenon are developed. In general, extensive overlap in weight between samples of captive and wild primates is documented. © 1994 Wiley-Liss, Inc.  相似文献   
650.
Hemolytic uremic syndrome (HUS) is an uncommon complication of chemotherapy that contributes to the morbidity of oncology and bone marrow transplant patients. The pathogenesis is not well understood and no established clinical animal model exists. We studied four rhesus monkeys (RM) that developed fatal HUS following high-dose chemotherapy. Microangiopathic hemolytic anemia (pre-Hct 40% and day 5–8 Hct 31 % (P <.05), increased BUN (168 mg/dl), creatinine (8.2 mg/dl), and lactate dehydrogenase (1458 IU/L) (mean day 5–8 measurements) were observed. Platelets counts decreased to 39±15 × 109/l from a mean of 397±31 × 109/L (P < .0001). vWF, ATIII, thrombin:anti-thrombin complex (T:AT) and prothrombin fragment F1.2 levels were not different from a control group (N = 2). The data presented describe chemotherapy-induced HUS with typical clinical and laboratory features which may provide an animal model for the study of this important syndrome.  相似文献   
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