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581.
Lorna D. Johnson Andrew J. Petto Prabhat K. Sehgal 《American journal of primatology》1991,25(2):91-102
Captive colonies of cotton top tamarins experience a high rate of rejection of infants within the 1st week of life. The rates of rejection and survival to maturity (2 or more years) among 659 live colony-born infants were correlated with rearing, birth group, litter size, season of birth, gender, origin of parents, experience of parents raising siblings, parity and age of parents, and experience of parent pairs. The most important factors associated with low rejection rates were family life and parental experience raising infants. Infants born into family groups or reared in families were rejected at a significantly lower rate. Rejection of infants whose sires were raised with siblings was significantly lower. Paternal experience was more important than maternal experience. Litter size had no effect on rejection of infants born to family groups, whereas, rejection of triplets was significantly higher than twins or singles among those born to parents alone. Rejection was significantly higher among primiparous births than multiparous birth. The combined experience of colony-born parents was not related to rejection if there were no sibling helpers in the cage at the time of birth. Rejection was significantly lower if sibling helpers were present. High survival of infants who were not rejected was correlated with rearing by or being born into family groups and higher parity and older age of the sires. 相似文献
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583.
Rajpati Dwivedi 《Plant and Soil》1972,37(1):171-172
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Effect of calcium glucarate on beta-glucuronidase activity and glucarate content of certain vegetables and fruits 总被引:2,自引:0,他引:2
C Dwivedi W J Heck A A Downie S Larroya T E Webb 《Biochemical medicine and metabolic biology》1990,43(2):83-92
Glucarate is normally present in tissues and body fluids and is in equilibrium with D-glucaro-1,4-lactone, a natural inhibitor of beta-glucuronidase activity. Dietary calcium glucarate, a sustained-release from of glucarate, elevates the blood level of D-glucaro-1,4-lactone which suppresses blood and tissue beta-glucuronidase activity. A single dose of CaG (4.5 mmole/kg body weight) inhibited beta-glucuronidase activity in serum and liver, lung, and intestinal microsomes by 57, 44, 37, and 39%, respectively. A chronic administration of calcium glucarate (4% in diet) also decreased beta-glucuronidase activity in intestinal and liver microsomes. Maximal inhibition of beta-glucuronidase activity in serum was observed from 12 noon to 2:00 PM. In contrast, maximum inhibition of beta-glucuronidase activity in intestinal and liver microsomes occurred during mornings, although a secondary depression in intestinal microsomes also occurred around 4 PM. A 4% calcium glucarate supplemented diet also inhibited beta-glucuronidase activity by 70% and 54%, of the bacterial flora obtained from proximal (small intestine) and distal (colon) segments of intestine, respectively. Due to the potential effect of dietary glucarate on net glucuronidation and on other metabolic pathways, glucaric acid levels in various foods were determined. The glucaric acid content varied from a low of 1.12-1.73 mg/100 g for broccoli and potatoes to a high of 4.53 mg/100 g for oranges. 相似文献