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31.
Olive Pink studied anthropology at the University of Sydney under Professor A.P. Elkin. Although she did fieldwork among the Northern Aranda and Wailbri of Central Australia, she became disenchanted with anthropology and lived a reclusive life in Alice Springs. In this paper I present a brief outline of her life, particularly during the 1930's I point to the problems she encountered and suggested that she needs to be relocated within her discipline.  相似文献   
32.
We have quantitatively documented the development of sex differences in the behavior of juvenile Japanese macaques (1 to 2 years of age). Mothers treated their offspring differently by sex, i.e., mothers of males broke contact with them more frequently than did mothers of females. Juvenile males played more, and mounted other macaques more frequently; juvenile females groomed their mothers more and were also punished by other group members more frequently than were males. Males showed a pattern of decreasing interactions with their mothers, but females increased the frequency of their maternal interactions. These patterns appear to presage the life histories of the sexes. However, comparisons with other species of nonhuman primates indicate that although sex differences in behavior are common, the variability among species severely limits cross-specific generalizations.  相似文献   
33.
The behavioral interactions of 22 infant and mother Japanese macaques with other group members were studied. Focal-animal observations were made from the time of each infant’s birth until 1 year of age. Infants and mothers both displayed exceedingly strong preferences for associating with matrilineal kin and, specifically, for female kin. The degree of genetic relatedness was positively correlated with levels of spatial proximity, contact, grooming, aggression, and play. Overall frequencies of interactions with nonkin were very low, and partner sex was not an important factor in interactions with nonkin. There were no significant differences between male and female infants in interactions with kin versus nonkin. There was only one significant difference between male and female infants in interactions with males versus females: female infants showed stronger preferences for initiating proximity with females over males than did male infants. Because mothers provide the focal point for infant interactions during the first year of life, we compared the behavior of infants and mothers. Mothers were the recipients of more social interactions than were infants, mothers engaged in more grooming than did infants, and infants engaged in more social play than did mothers. These findings are only partially consistent with kin-selection theory, and the inadequacies of studying matrilineal kin discrimination to test kin selection are reviewed. The near-absence of infant sex differences in associations with social partners suggests that although maternal kin other than the mother are important to infant socialization, they probably do not contribute to the development of behavioral sex differences until after the first year of life.  相似文献   
34.
Quantitative data are presented on the effects of subject sex, partner sex,and kinship on the social interactions of 18 juveniles of the Oregon troop of Japanese macaques (Macaca fuscata).Data on these subjects as infants were also used to detail maturational changes in partner sex preferences. Nine males and nine females, whose multiparous mothers represented a cross section of dominance ranks, were observed using a focal-animal technique. Juveniles of both sexes engaged in more proximity, contact, grooming, mounting, aggression, and social play with kin than with nonkin partners. They initiated less contact with females and more contact with males during their second year. They initiated more grooming and aggression during their second year than their first year, with females displaying a strong preference for grooming females and males specifically aggressing males more during the second year. Aggression was higher between same-sexed partners than between opposite-sexed partners. Males engaged in more social interactions with males during the second year than the first year of life. Males played more than females during both years. Males played more with males during the second year than the first year, and males played with males more than did females during the second year. We conclude that sex differences in behavioral frequencies become evident during the first year of life, and sex differences in partner preferences emerge during the second year of life.  相似文献   
35.
Chloroperoxidase catalyzes the peroxidation of primary alcohols, specifically those that are allylic, propargylic, or benzylic. Aldehydes are the products. The reaction dislays appreciable activity throughout the entire pH range investigated, namely pH 3.0–7.0. This enzyme is the only haloperoxidase of four tested capable of carrying out the reaction. These results further establish chloroperoxidase as a unique haloperoxidase.  相似文献   
36.
Electrical activity in the fertilized egg of the tunicate Clavelina was studied with microelectrode recording and voltage clamp techniques. The resting potential could assume either of two stable values (approximately ?70 or ?30 mV) and could be shifted between these values by direct current stimulation. Spontaneous shifts between two stable resting potentials were also seen. Egg cells produced action potentials spontaneously and in response to depolarizing stimuli. Inward currents were carried by both Na and Ca ions and a prominent outward potassium current was seen with depolarization to voltages above ?15 mV. The steady-state current-voltage relationship (I–V curve) of the membrane showed two voltages where the net membrane current equaled zero: approximately ?35 and ?70 mV. Between these two voltages, membrane current was inward and carried by noninactivating Na and Ca currents. Inward rectification, which was blocked by external Rb, occurred at voltages below ?70 mV. The voltage dependence of inward rectification is thought by the authors to be important for establishing the more negative resting potential; it is also thought the presence of inward current which does not inactivate completely at voltages more negative than about ?20 mV is an important determinant of the more depolarized resting potential.  相似文献   
37.
Summary Aspartate transcarbamoylase (ATCase, EC 2.1.3.2) is the first unique enzyme common to de novo pyrimidine biosynthesis and is involved in a variety of structural patterns in different organisms. InEscherichia coli, ATCase is a functionally independent, oligomeric enzyme; in hamster, it is part of a trifunctional protein complex, designated CAD, that includes the preceding and subsequent enzymes of the biosynthetic pathway (carbamoyl phosphate synthetase and dihydroorotase). The complete complementary DNA (cDNA) nucleotide sequence of the ATCase-encoding portion of the hamster CAD gene is reported here. A comparison of the deduced amino acid sequences of the hamster andE. coli catalytic peptides revealed an overall 44% amino acid similarity, substantial conservation of predicted secondary structure, and complete conservation of all the amino acids implicated in the active site of theE. coli enzyme. These observations led to the construction of a functional hybrid ATCase formed by intragenic fusion based on the known tertiary structure of the bacterial enzyme. In this fusion, the amino terminal half (the “polar domain”) of the fusion protein was provided by a hamster ATCase cDNA subclone, and the carboxyl terminal portion (the “equatorial domain”) was derived from a clonedpyrBI operon ofE. coli K-12. The recombinant plasmid bearing the hybrid ATCase was shown to satisfy growth requirements of transformedE. coli pyrB cells. The functionality of thisE. coli-hamster hybrid enzyme confirms conservation of essential structure-function relationships between evolutionarily distant and structurally divergent ATCases.  相似文献   
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The humanNBR1cDNA has previously been identified using polyclonal sera to CA125, an ovarian tumor antigen used in monitoring ovarian cancer. The gene was mapped to theBRCA1region on chromosome 17q21 and subsequently found to lie in close proximity to the recently identifiedBRCA1gene. The NBR1 protein has a B-box motif but the function of the protein is as yet unknown. To investigate the function and importance of this gene, we have studied the conservation of this gene in other species and in particular in the mouse. We have isolated murineNbr1cDNA and genomic clones. Translation of the cDNA sequence indicates that the protein is highly conserved, being 89% similar and 84% identical to the human. Analysis of the murineNbr1genomic clones indicates that it maps less than 1 kb from theBrca1gene and that, unlike that in human, this region is not duplicated.  相似文献   
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