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131.
G. Gray Eaton Deanne F. Johnson Barbara B. Glick Julie M. Worlein 《Primates; journal of primatology》1986,27(2):141-150
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
132.
Barbara Beckerman Glide G. Gray Eaton Deanne F. Johnson Julie Worlein 《International journal of primatology》1986,7(2):139-155
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
133.
Glick Barbara Beckerman Eaton G. Gray Johnson Deanne F. Worlein Julie M. 《International journal of primatology》1986,7(5):467-479
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
134.
N Le Trant S R Meshnick K Kitchener J W Eaton A Cerami 《The Journal of biological chemistry》1983,258(1):125-130
Leishmania tropica, Trypanosoma brucei, Trypanosoma cruzi, and Crithidia fasciculata have superoxide dismutases which are insensitive to cyanide and sensitive to peroxide and azide, properties characteristic of iron-containing superoxide dismutase. Studies on the superoxide dismutase of C. fasciculata have revealed that: 1) the enzyme is located in the cytosol; 2) isozymes exist; 3) the major superoxide dismutase isozyme (superoxide dismutase 2) has Mr approximately equal to 43,000 and consists of two equal-sized subunits, each of which contains 1.4 atoms of iron. Comparisons of the amino acid content of this crithidial superoxide dismutase with those of superoxide dismutases from other sources suggests that the crithidial enzyme is closely related to bacterial Fe-containing superoxide dismutases, and only distantly related to human Mn- and Cu,Zn-containing superoxide dismutases and to Euglena Fe-containing superoxide dismutase. Attempts are now underway to develop specific inhibitors of the trypanosomatid superoxide dismutase which may be of use in the treatment of leishmaniasis or trypanosomiasis. 相似文献
135.
E K Weir J A Will L J Lundquist J W Eaton E Chesler 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1983,173(1):96-103
Diamide oxidizes glutathione and other cellular sulfhydryl groups. It decreases calcium ATPase activity and alters mitochondrial calcium flux, probably as a result of the sulfhydryl oxidation. We examined the effect of diamide (5 mg/kg, iv) on pulmonary vascular reactivity in 12 anesthetized dogs. Diamide reversed the pulmonary vasoconstriction caused by hypoxia in seven dogs (control delta PVR + 2.5 +/- 0.6 mm Hg/liter/min; postdiamide delta PVR - 0.1 +/- 0.4 mm Hg/liter/min; P less than 0.01). The pulmonary pressor response to prostaglandin F2 alpha (5 micrograms/kg/min, iv) was also reduced (control delta PVR + 3.8 +/- 0.5 mm Hg/liter/min; postdiamide delta PVR + 1.1 +/- 0.7 mm Hg/liter/min; P less than 0.01). However, in a further five dogs, diamide had only a small effect on the pulmonary vasoconstriction caused by angiotensin II, while the pressor response to hypoxia was again inhibited. The mechanism by which diamide reverses pulmonary vasoconstriction is not certain but the effect is rapid, consistent, and reversible. Because the intravenous infusion of diamide does not produce systemic hypotension, during its period of action on the pulmonary vasculature, unlike the drugs currently available for the clinical treatment of pulmonary hypertension, further studies of its mechanism of action are indicated. 相似文献
136.
Amiloride-inhibited Na+ transport into toad urinary bladder microsomes is sensitive to a pH gradient across the vesicular membrane. The magnitude of the gradient was measured directly with acridine orange. Also Na+ could stimulate amiloride-sensitive proton efflux from the microsomes. These results indicated that the transport process was Na+-H+ exchange. 相似文献
137.
Linear, Single-Stranded Deoxyribonucleic Acid Isolated from Kilham Rat Virus 总被引:9,自引:9,他引:0 下载免费PDF全文
Kilham rat virus (KRV) was grown in a rat nephroma cell line and was purified by two isopycnic centrifugations in cesium chloride. The virus contains single-stranded deoxyribonucleic acid (DNA) with a molecular weight of approximately 1.6 x 10(6). The DNA was extracted from the virion by both phenol extraction and by 2% sodium dodecyl sulfate at 50 C. KRV DNA, extracted by both procedures, was observed in an electron microscope by using a cytochrome c or diethylaminoethyldextran monolayer. The DNA was also exposed to exonuclease I, an enzyme which hydrolyzes specifically linear, single-stranded DNA. Hydrolysis of 70 to 80% of the DNA was observed. Both the enzymatic and the electron microscope studies support the conclusion that extracted KRV DNA is a single-stranded, linear molecule. The length of the DNA was measured in the electron microscope and determined to be 1.505 +/- 0.206 mum. 相似文献
138.
Summary In contrast with the toxicities of sulfate and chloride salts added to substrates, the anions SO4 and C1 were not injurious when accumulated without leaf burning by cotton and tomato plants from atmospheres enriched with
SO2 or HC1 gases. The foregoing results are discussed in terms of cationenzyme interactions which appear to represent at least
a major cause of salt toxicity. Although anions are largely unreactive with enzymes it has long been observed that chloride
salts in soil solutions are far more toxic than sulfate salts. Five of seven species have shown nearly equal growth repressions
on substrates with 100 me/1 of C1 salts versus 200 me of SO4 salts, each added as 50 per cent Na. The ion activities of the two solutions were equal and the sum of cations in the plant
saps were similar. The osmotic differentials (average about 10 atm) between the expressed tissue fluids and these substrate
solutions were remarkably uniform within species. It is projected that the downward transport of salts via the phloem provides
for root concentrations which supply ions to the xylem and thereby control the uptake of substrate salts. 相似文献
139.
Genetic Transformation of Biosynthetically Defective Neisseria gonorrhoeae Clinical Isolates 总被引:15,自引:7,他引:8 下载免费PDF全文
B. Wesley Catlin 《Journal of bacteriology》1974,120(1):203-209
Deoxyribonucleic acid (DNA) and chemically defined media were used in transformation tests of 51 strains of Neisseria gonorrhoeae which exhibited various biosynthetic defects when isolated from patients. These auxotrophic gonococci had one or more nutritional requirements involving proline, methionine, arginine, hypoxanthine, uracil, and thiamine pyrophosphate (THPP). DNA from a clinical isolate which did not require these compounds for growth on defined medium transformed each of the auxotrophic markers of all 51 recipient populations. Ten isolates had defects involving the synthesis of THPP; four strains (designated Thp(-)) had a growth requirement that was satisfied only by THPP, whereas the requirement of six strains (designated Thi(-)) was satisfied by either thiamine or THPP. DNA from Thp(-) donors elicited transformation of Thp(-) as well as Thi(-) recipients. Reciprocally, DNA from a Thi(-) donor transformed both Thi(-) and Thp(-) recipients. Furthermore, DNA from other auxotrophic gonococci had transforming activity for some phenotypically similar auxotrophic recipients. The findings indicate the existence of various nonidentical genetic defects which block reactions in the biosynthesis of proline, methionine, arginine, hypoxanthine, and THPP. Routine cultures from patients with gonorrhea were the source of these auxotrophic strains of N. gonorrhoeae; the various nutritional requirements were identified by a recently described system of gonococcal auxotyping. The transformation test results verify the hereditary basis of the auxotypes, establish that many different mutations exist in potentially virulent gonococci, and illustrate the value of these auxotrophic mutants for studies of the genetic structure and evolution of natural populations of gonococci. 相似文献
140.
Plasma testosterone levels measured by radioimmunoassay did not correlate with dominance rank or aggressive behavior in 21 adult males of a natural troop of Japanese macaques (Macaca fuscata). The data were replicated during two consecutive breeding seasons. Levels of male dominance and aggressive behavior were highly correlated from year to year, but testosterone levels of individual males were not. Nor were individual levels of testosterone correlated in five laboratory males sampled every 15 min over a 2-hr period. These laboratory males showed multiple, apparently random peaks but the mean testosterone level of 11.73 ng/ml did not vary significantly throughout the 120 min that were studied. By demonstrating that the stress of blood collection did not depress plasma testosterone titers in laboratory males, these data validated the method used in the study of the natural troop. 相似文献