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21.
Donna Robbins Colin A. Chapman Richard W. Wrangham 《Primates; journal of primatology》1991,32(3):301-305
Gibbons and spider monkeys have similar diets, body size, and locomotor patterns. They are therefore expected to be subject
to similar socioecological rules. However their grouping patterns differ. Gibbons live in small stable groups, whereas spider
monkey form unstable sub-groups that vary from small to large during different seasons. If similar principles apply to the
two species, food abundance should vary more for spider monkeys than for gibbons; food density should be similar for the two
species when spider monkey sub-groups are the same size as gibbon groups; and the highest level of food abundance should be
higher for spider monkeys than for gibbons. These predictions are upheld for a comparison of particular populations ofHylobates muelleri andAteles geoffroyi. 相似文献
22.
Results from three experiments on basic learning and transfer in rhesus monkeys (Macaca mulatta) are reported in which fully automated testing paradigms, afforded by the Language Research Center's Computerized Test System
(LRC-CTS), were employed. Performance levels for discrimination learning set, transfer index, and mediational-learning testing
were uniformly higher than was predicted from the literature, in contrast to previous reports of compromised learning under
similar conditions (automated apparatus, planimetric stimuli, spatial discontiguity between stimuli and response loci). Analyses
reveal relatively advanced learning set performance, transfer-index ratios, and positive transfer of learning even at stringent
criterion levels. Moreover, the data suggest that rhesus monkeys tested in these experiments exhibit mediational instead of
associative learning strategies, as do great apes and in contrast to previous reports of rhesus learning. We argue that the
LRC-CTS enhances learning by nonhuman primate subjects, obviating those factors, reported in the literature from experiments
in which manual or other automated systems were employed, that compromise learning. 相似文献
23.
24.
促性腺激素诱导猕猴排卵周期中卵巢纤溶酶原激活因子与抑制因子的变化 总被引:1,自引:0,他引:1
在用 PMSG 和 hUG 诱导猕猴排卵过程中,我们研究了 pA 和它的抑制因子 PAI-1与排卵的关系。实验结果表明,由促性腺激素所诱导出的卵巢 tPA 活性的增加与排卵密切相关,在排卵前达到高峰,而排卵后明显下降;uPA 只在排卵后的颗粒细胞大量出现;PAI-1分泌高峰比 tPA 峰值早出现12—24小时;排卵来临时,tPA 的明显上升导致 PAl-1的空然下降。上述实验结果说明,卵巢中 tPA 和 PAI-1活性的这种平衡性的变化可能在排卵机制和维持卵巢的正常生理功能中起重要作用,而 uPA 或许与黄体形成的调节有某些关系。 相似文献
25.
横断山齿突蟾属一新种(两栖纲:锄足蟾科) 总被引:2,自引:0,他引:2
1982年在横断山区考察期间,发现四川木里截族自治县的齿突蟾Scutiger标本在第二性征、趾蹼等特征与已知的各种齿突蟾均不相同,描述为新种木里齿突蟾Scutiger muliensis。 相似文献
26.
The hair density of free-ranging Japanese monkeys (Macaca fuscata fuscata) living in three different areas was investigated. The Japanese monkeys had thicker hair than other macaques. The hair density
in the Japanese monkeys varied with locality: the northern monkeys had thicker hair than the southern ones. The density did
not vary markedly with age up to 3 years of age, but then decreased gradually up to adult age (≧7 years old). The remarkable
growth of the trunk suggested that the total number of hairs increased with age, especially during the period as a juvenile. 相似文献
27.
The performance of The Subhuman Primate Pregnancy Test Kit was evaluated for routine detection of early (days 19-21) pregnancy in the rhesus monkey. Out of 123 confirmed matings, 19 resulted in pregnancy. In the pregnant animals the kit had an accuracy of 73.7%. In the nonpregnant females the accuracy was higher, 88.5%. False positives were encountered in ovariectomized females as well as adult intact males. 相似文献
28.
Bolivian squirrel monkeys, unlike those of Brazilian origin, exhibit a marked fasting hyperbilirubinemia (FH) similar to that observed in Gilbert's syndrome in man. Since no delays in the hepatic clearance of sulfobromophthalein or indocyanine green are present, the Bolivian monkey appears to be similar to Gilbert's type I syndrome. FH can be significantly decreased by either phenobarbital or tin-protoporphyrin pretreatment. Nicotinic acid-induced hyperbilirubinemia and delayed tolbutamide clearance were not observed as in the human syndrome. 相似文献
29.
本文对扁头中国短头鲵(新属新种) (Sinobrachyops placenticephalus gen. et sp. nov.) 的形态特征和分类位置进行简述.标本得自著名的恐龙化石产地——自贡大山铺,产出时代为中侏罗世.中国短头鲵是目前迷齿类中在地史上最年轻的一个属.它的发现使迷齿类在地球上生存时代的上限推移到中侏罗世. 相似文献
30.
Spontaneous malignant lymphoma in an African green monkey naturally infected with simian T-lymphotropic virus (STLV) 总被引:4,自引:0,他引:4
I Sakakibara Y Sugimoto A Sasagawa S Honjo H Tsujimoto H Nakamura M Hayami 《Journal of medical primatology》1986,15(5):311-318
An African green monkey naturally infected with simian T-lymphotropic virus (STLV) developed spontaneous malignant lymphoma of diffuse pleomorphic type. The clinical, hematological and histopathological characteristics were very similar to those of human adult T-cell leukemia. 相似文献