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21.
Takahiro Tsukahara 《Primates; journal of primatology》1990,31(2):147-156
Grooming initiation among adult males and females of a Japanese macaque troop was analyzed during the non-mating season. Some
gestures (“solicitation”) elicited grooming from partners at a high rate. Grooming initiation patterns were divided into two
main types: (1) a male often solicited a female to groom him immediately after approaching her and was groomed by her; and
(2) a female approached an alpha male selectively, and immediately groomed him. After a female groomed a male, she rarely
solicited him to groom her and instead often moved away from him. These results indicated that males were motivated to be
groomed, while females were more highly motivated to groom. Sex differences in grooming motivation can be explained by sex
differences in the benefit to be groomed. 相似文献
22.
Donna K. Stafford Garrett W. Milliken Jeannette P. Ward 《Primates; journal of primatology》1990,31(3):407-414
Lateralized hand use in gibbons was assessed for both food reaching and leading limb in brachiation. Sex and age effects were
found in hand preference for food reaching. Adult females were all very strongly right hand preferent, whereas adult males
had no across group consistent preference. Within the female group there was a strong correlation between age and strength
of right handedness. When compared in terms of absolute strength of hand preference, females were found to be more strongly
lateralized than males. Leading limb preference in brachiation was scored into vocal and non-vocal categories. Three subjects
had a shift in preferred leading limb from the non-vocal brachiation condition to the vocal brachiation condition. This shift
may be influenced by the arousal effects of species typical vocalization. The results of this study underline the importance
of consideration of such factors as sex and age when interpreting behavioral lateralization data. The exploration of laterality
in many different response measures is important to the achievement of a complete understanding of behavioral lateralization
in primates. 相似文献
23.
Penetration of intact bovine ova with ram sperm in vitro 总被引:1,自引:0,他引:1
In culture, mature bovine ovarian oocytes were fertilized in vitro with freshly ejaculated ram spermatozoa treated with heparin. The zona pellucida does not prevent penetration of ram spermatozoa. The penetration rate varied between 10 and 84%, and in most instances, after 24 hr of culture, two normal-looking pronuclei and sperm tail were present in the cytoplasm. These results suggest that the zona pellucida of bovine oocytes does not represent a barrier for the penetration of ram spermatozoa. 相似文献
24.
25.
Kenji Kawanaka 《Primates; journal of primatology》1993,34(3):255-270
Proximity partner choice by male chimpanzees of various age classes was analyzed in relation to their spatial positioning.
Field work was carried out twice at the Mahale Mountains National Park, Tanzania. Proximity data were recorded at 3 and 10m
from the focal animal. The data for the proximity between the focal male and other individuals allowed the males to be classified
into two categories according to both criteria: early adolescence to young adult, and prime to old age. Between the males,
the 3m proximity data permitted a classification into two categories as above, but those for 10m did not. These two spatial
distances thus probably have different meanings for the males. The numbers of male proximity partners and proximity with the
alpha male also allowed the males to be classified into two categories: early and late adolescence, and young adult to old
age. Together, the above results support the classification of males into three age-graded categories: (1) early and late
adolescence, (2) young adult, and (3) prime to old age. This does not arise because the males of each category form an age
group. Prime or older males are most frequently in proximity, while their juniors consistently attempt to approach them. However,
even prime or older males are not equally in proximity with one another. Their proximity partners change as time passes. Probably
recognizing such changes, they form coalitions or are in rivalry. The sexual interest of adolescent males is probably a factor
stimulating them to separate from their mothers, and to approach older males. Young adult males, even though physically mature,
do not have equal proximity relations with older males. They are not yet sufficiently qualified to join the coalitions formed
by their seniors. 相似文献
26.
细胞核移植技术已被证明是研究发育中核质相互关系的非常重要的手段之一,电融合技术也是近十年发展起来的新型细胞融合技术。本实验运用这两项技术,进行了鼠、兔目间核质杂交实验,小鼠8-细胞核在激活的兔去核卵母细胞中,发生了染色体超前凝聚及核膨胀,融合卵移植到小鼠输卵管4.5天后,冲洗出,有5.4%的重构卵发育到囊胚期,通过染色体检查,囊胚细胞中均为小鼠染色体,其中一个囊胚为正常小鼠核型(2 n=40,XX)。通过本实验,我们认为:鼠兔远缘核质杂交胚胎的早期发育是可能的。 相似文献
27.
To be able to understand cellular mechanisms, we require fully integrated data sets combining information about gene expression, protein expression, post-translational modification states, sub-cellular location and complex formation. Proteomics is a very powerful technique that can be applied to interrogate changes at the protein level. Studying this effectively requires specialised facilities within research institutes. Here, we describe the setting up and operation of such a facility, providing a resource for the Arabidopsis and Drosophila research communities. 相似文献
28.
Impact of dengue virus infection and its control 总被引:3,自引:0,他引:3
Akira Igarashia 《FEMS immunology and medical microbiology》1997,18(4):291-300
29.
Ouabain-blocked toad urinary bladders were maintained in Na+-free mucosal solutions, and a depolarizing solution of high K+ activity containing only 5 mM Na+ on the serosal side. Exposure to mucosal sodium (20 mM activity) evoked a transient amiloride-blockable inward current, which decayed to near zero within one hour. The apical sodium conductance increased in the initial phase of the current decay and decreased in the second phase. The conductance decrease required Ca2+ to be present on the serosal side and was more rapid when the mucosal Na+ activity was higher. At 20 mM mucosal Na+ and 3 mM serosal Ca2+ the initial (maximal) rate of inhibition amounted to 20% in 10 min. The conductance decrease could be accelerated by raising the serosal Ca2+ activity to 10 mM. The inhibition reversed on lowering the serosal Ca2+ to 3 μM and, in addition, the mucosal Na+ to zero. Exposure of the mucosal surface to the ionophore nystatin abolished the Ca2+ sensitivity of the transcellular conductance, showing that the Ca2+-sensitive conductance resides in the apical membrane. The data imply that in the K+-depolarized epithelia, cellular Ca2+, taken up from the serosal medium by means of a Na+-Ca2+ antiport, cause feedback inhibition by blockage of apical Na+ channels. However, the rate of inhibition is small, such that this regulatory mechanism will have little effect at 1 mM serosal Ca2+ and less than 20 mM cellular Na+. 相似文献
30.
Yukio Takahata Toshikazu Hasegawa Toshisada Nishida 《International journal of primatology》1984,5(3):213-233
Fifty-four episodes of predatory behavior of wild chimpanzees were recorded in Mahale, western Tanzania, from August 1979
to May 1982. The chimpanzees most frequently hunt in two seasons, during May, and from August to December. Longer-term fecal
analysis indicates that predation frequency is significantly higher in the dry than in the rainy season. The seasonality of
predation might be the result of the sum of various ecological factors, at least one of which is the birth season of the prey
species. Most of the prey are juvenile blue duiker, bushbuck, bushpig, red colobus, and red-tailed monkeys. Sex difference
is recognized in the prey selection and in the hunting method employed. Apparent local difference in the predatory behavior
between Mahale and Combe chimpanzees (in Mahale,females hunt more frequently, and blue duiker is the most frequent prey) can be understood in terms of the difference either
in the observation methods or in the faunal diversity and density. Other aspects of predatory behavior also are reported. 相似文献