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1.
Both dl-Delta(8)- and dl-Delta(9)-tetrahydrocannabinol produced marked alterations of behavior in rhesus and squirrel monkeys. Squirrel monkeys appeared to have visual hallucinations. Continuous avoidance behavior of squirrel monkeys was stimulated by both drugs, but high doses of dl-Delta(9)-tetrahydrocannabinol also caused depression after the stimulant phase. Complex behavior involving memory and visual discrimination in rhesus monkeys was markedly disrupted by both drugs.  相似文献   

2.
The heart is a target organ for androgen   总被引:5,自引:0,他引:5  
Autoradiographic and biochemical analyses of the hearts of female rhesus monkeys and baboons indicate that atrial and ventricular myocardial cells contain androgen receptors. Although the specific effects of nuclear uptake and retention of androgen on the function of heart muscle cells are not known, the presence of this receptor suggests that sex steroid hormones may affect myocardial function directly and may explain some of the peculiar differences in heart disease between men and women.  相似文献   

3.
Two hundred thirty of the feral rhesus monkeys on Cayo Santiago were observed individually for postural adjustments, locomotor behavior, manipulation, and other nonsocial activities. Both form and frequency of activity were influenced strongly by age; sex differences were minimal. Most activities decreased with age, but head movements, presumably reflecting visual scanning, were more frequent in adults.  相似文献   

4.
Three patterns of electrical response were identified in the occipital cortex of rhesus monkeys making a differential discrimination: an input pattern that identifies which stimulus has been displayed; a reinforcement pattern that indicates whether the outcome of the differential response was rewarded or in error; and an intention pattern that occurs prior to the response and predicts which response the monkey is about to make. Neither the reinforcement nor the intention pattern is present while the monkeys perform at chance; at this time, only the differences due to input can be distinguished. These results suggest that more than simple input transmission is occurring in the primary visual mechanism. The influence of the experience of the organism is apparently encoded in the averaged electrical potentials recorded from the striate cortex.  相似文献   

5.
The eflect of uncinectomny on the social behavior of free-ranging rhesus monkeys was observed on Cayo Santiago Island. Operated subjects showed social indifjerence, failed to display appropriate aggressive and submissive gestures. were expelled from their social group, and evenitlually died. Two juvenile subjects with the lesion restricted to amygdala survived and have rejoinied their social group. Size of lesion and age at operation were major factors in determniting the degree of behavioral change.  相似文献   

6.
ENOCH JM 《Science (New York, N.Y.)》1961,133(3461):1353-1354
Retinal receptor wave-guide modal patterns have been photographed. The inner and outer segments of the rod and cone receptors of albino rats, rhesus macaque monkeys, and human beings have been studied. The wave-guide modal pattern is believed to be the normal form of energy transfer in these parts of the retinal receptors in these species.  相似文献   

7.
Photuris males emit flashed signals matching those of unrelated sympatric forms (Photinus and Pyractomena species). Some have only one flash pattern matching that of another species, others mimic at least two species, as well as emitting "their own" species-specific pattern. They tend to restrict the mimicking signals, but not their own, to the habitats, seasons, and daily periods of the mimicked species. Since Photuris females prey on males of other firefly species by mimicking their females' flashes, the Photuris males may be using their mimicry to locate and seduce their own hunting females. This mimicry is without known parallel in other animal communicative systems. It explains why the genus Photuris has been a frustrating mystery to taxonomists, who have long used flash patterns to distinguish sibling species in other genera.  相似文献   

8.
Infection has been obtained in both rhesus and cynomolgus monkeys by inhalation of poliomyelitis virus in the form of droplet nuclei. The olfactory route was excluded in part of the animals successfully infected. The gastrointestinal route is believed to have been excluded in the rhesus monkeys. It seems most probable that the portals of entry were the lower respiratory mucosa in the case of the rhesus monkeys and the oropharyngeal mucosa in the case of the cynomolgus monkeys. Fever and occasional mild symptoms in 8 other rhesus monkeys suggest that an abortive form of poliomyelitis may have resulted from inhalation, but this can not at present be considered as proved. The experiments open up the possibility that human poliomyelitis may, at least sometimes, be an air-borne infection and that the lungs may be a portal of entry. Neither of these aspects of the disease has hitherto, so far as we are aware, been studied experimentally. The presence of virus in the human nasopharynx, which has been repeatedly demonstrated,(7, 8) provides an obvious source of air contamination by patients and carriers; and direct contact has been traced during epidemics in a considerable fraction of cases,(9) amounting to about one third in the report of Top and Vaughan.(10) The relative importance of transmission by air and by ingested material remains to be determined. It would seem probable, however, that both modes of infection must be taken into account.  相似文献   

9.
Effects of brief separation from mother on rhesus monkeys   总被引:2,自引:0,他引:2  
To summarize, data on the course of development of mother-infant relations in rhesus monkeys have been presented; a method for teasing apart the relative roles of mother and infant in causing changes or differences in the interaction described; and the complexity of the social nexus, within which the relationship is set, stressed. When the mother is removed for a few days, the infant calls a great deal at first and then shows depressed locomotor and play activity. These symptoms may last for a month after the mother's return. Simple tests given 6 months and even 2 years later strongly suggest that the differences (between infants that have had such a separation experience and infants that have not) are persistent. Are these data relevant to the human case? The rhesus monkey has no verbal language and a much less complex social development than man. Furthermore, its social environment is quite different from that found in any human culture. Parallels between monkey and man must therefore be scrutinized carefully before being used as a basis for generalization. But the facts show that a brief separation experience produces in rhesus monkey infants symptoms that are very similar (except for the apparent absence of a "phase of detachment" on reunion) to those in human infants (25). While age of separation, within the rather narrow limits used here, was a variable of minor importance, the effects of the separation varied, as in the human case, with the length of the separation experience and the sex of the infant. Differences in the techniques of experimenters, as well as differences in the species, prevent precise comparisons of the roles of the mother-infant relationships; nevertheless, the nature of the relationship appears to be an important variable in both monkey and man. There would seem, therefore, to be strong reasons for thinking that we are dealing with comparable phenomena. If that is the case, the fact that monkeys function at a simpler conceptual level than man limits the complexity of the explanatory hypotheses necessary in the human case. In addition, the finding that such a brief separation experience, involving removal of the mother but no exposure to a strange environment, can produce effects lasting for months or years in rhesus monkeys strengthens the evidence that long-term effects may occur also in man. Finally, this analysis provides bases for attempts to predict individual differences in the effects of a period of separation on rhesus infants, and the parallels with man suggest that examination of the same variables in the human case would be worthwhile.  相似文献   

10.
In primates, each hemisphere contains a representation of the contralateral visual hemifield; unilateral damage to the visual pathways results in loss of vision in half of the visual field. Apparently similar severe, unilateral lesions to the central visual pathways can result in two qualitatively different central visual field defects termed macular sparing and macular splitting. In macular sparing a 2 degrees to 3 degrees region around the fovea is spared from the effects of unilateral damage to the visual pathways. In macular splitting there is no such spared region and the scotoma produced by unilateral brain damage bisects the fovea. The patterns of decussation of the different classes of retinal ganglion cells in both New World (Saimiri sciureus) and Old World (Macaca fascicularis) monkeys have been determined by horseradish peroxidase injection. In both species the distributions of ipsilaterally and contralaterally projecting ganglion cells in the central retina are different from those in other mammals and suggest neural bases for macular sparing and splitting, respectively.  相似文献   

11.
Inferior temporal (IT) cortex is critical for visual memory, but it is not known how IT neurons retain memories while new information is streaming into the visual system. Single neurons were therefore recorded from IT cortex of two rhesus monkeys performing tasks that required them to hold items in memory while concurrently viewing other items. The neuronal response to an incoming visual stimulus was attenuated if it matched a stimulus actively held in working memory, even when several other stimuli intervened. The neuronal response to novel stimuli declined as the stimuli became familiar to the animal. IT neurons appear to function as adaptive mnemonic "filters" that preferentially pass information about new, unexpected, or not recently seen stimuli.  相似文献   

12.
The role of the primate extrastriate area V4 in vision   总被引:5,自引:0,他引:5  
Area V4 is a part of the primate visual cortex. Its role in vision has been extensively debated. Inferences about the functions of this area have now been made by examination of a broad range of visual capacities after ablation of V4 in rhesus monkeys. The results obtained suggest that this area is involved in more complex aspects of visual information processing than had previously been suggested. Monkeys had particularly severe deficits in situations where the task was to select target stimuli that had a lower contrast, smaller size, or slower rate of motion than the array of comparison stimuli from which they had to be discriminated. Extensive training on each specific task resulted in improved performance. However, after V4 ablation, the monkeys could not generalize the specific task to new stimulus configurations and to new spatial locations.  相似文献   

13.
The endochondral growth apparatus of the mandibular condyles, in contrast to epiphyseal plates of long bones, reacts positively to mechanical stimulation. Roentgenographic and histologic analyses of the joint structures of two experimental rhesus monkeys, when compared with untreated controls, showed obvious morphologic and structural transformations of the condylar heads as the result of the instituted treatment. Corollary differences were found in the ontogenetic and histogenetic pattern, as well as in the hormonal control, of these condylar growth centers.  相似文献   

14.
Adults of three species of mosquitoes, Aedes aegypti, Anopheles quadrimaculatus and Culex pipiens, showed essentially similar patterns of nitrogen output as judged by their excretion of total nitrogen and by their excretion of nitrogen as uric acid, urea, ammonia, amino acid, and protein. About 80 percent of their total nitrogen has been accounted for. Substances that seem on analysis to be like glycoprotein have been found in the excreta of the three species.  相似文献   

15.
Multiple sensitive periods in the development of the primate visual system   总被引:5,自引:0,他引:5  
Early in life, abnormal visual experience may disrupt the developmental processes required for the maturation and maintenance of normal visual function. The effects of retinal image deprivation (monocular form deprivation) on four psychophysical functions were investigated in rhesus monkeys to determine if the sensitive period is of the same duration for all types of visual information processing. The basic spectral sensitivity functions of rods and cones have relatively short sensitive periods of development (3 and 6 months) when compared to more complex functions such as monocular spatial vision or resolution (25 months) and binocular vision (greater than 25 months). Therefore, there are multiple, partially overlapping sensitive periods of development and the sensitive period for each specific visual function is probably different.  相似文献   

16.
李贵  吕龙宝 《安徽农业科学》2014,(14):4374-4375,4396
阐述了恒河猴在人工饲养繁殖过程中,发生腰肢疾病的原因,发现腰肢疾病的致病原因主要有外伤、致病微生物、中毒、营养缺乏或代谢紊乱、环境潮湿阴冷、药物,并介绍了腰部疾病、四肢外伤性疾病、神经系统疾病、中毒性疾病的诊断思路,提出了驻立视诊、运动视诊和触诊等诊断方法.  相似文献   

17.
The determination of the chimpanzee genome sequence provides a means to study both structural and functional aspects of the evolution of the human genome. Here we compare humans and chimpanzees with respect to differences in expression levels and protein-coding sequences for genes active in brain, heart, liver, kidney, and testis. We find that the patterns of differences in gene expression and gene sequences are markedly similar. In particular, there is a gradation of selective constraints among the tissues so that the brain shows the least differences between the species whereas liver shows the most. Furthermore, expression levels as well as amino acid sequences of genes active in more tissues have diverged less between the species than have genes active in fewer tissues. In general, these patterns are consistent with a model of neutral evolution with negative selection. However, for X-chromosomal genes expressed in testis, patterns suggestive of positive selection on sequence changes as well as expression changes are seen. Furthermore, although genes expressed in the brain have changed less than have genes expressed in other tissues, in agreement with previous work we find that genes active in brain have accumulated more changes on the human than on the chimpanzee lineage.  相似文献   

18.
The neural integrator, which converts eye velocity signals into position signals, is central to oculomotor theory. Similar integrators are probably necessary in any neural system that changes and maintains muscular tension. The integrator for horizontal eye position is in the pons, but the locations of the vertical and torsional integrators have not been clearly defined. Recording three-dimensional eye movements in alert monkeys during microstimulation and pharmacological inactivation of midbrain sites showed that the interstitial nucleus of Cajal generates both the torsional and vertical eye position signals. Up and down signals are linked with clockwise signals in the right brain and counterclockwise signals in the left brain. This three-dimensional coordinate system achieves orthogonality and bilateral symmetry without redundancy and optimizes energy efficiency for horizontal visual scanning.  相似文献   

19.
Simian AIDS: isolation of a type D retrovirus and transmission of the disease   总被引:32,自引:0,他引:32  
A type D retrovirus related to but distinct from Mason-Pfizer monkey virus was isolated in vitro from the blood of two rhesus monkeys (Macaca mulatta) with simian acquired immunodeficiency syndrome (SAIDS). Three juvenile rhesus monkeys that were injected intravenously with tissue culture fluids containing this virus developed SAIDS after 2 to 4 weeks.  相似文献   

20.
Lentiviral delivery of glial cell line-derived neurotrophic factor (lenti-GDNF) was tested for its trophic effects upon degenerating nigrostriatal neurons in nonhuman primate models of Parkinson's disease (PD). We injected lenti-GDNF into the striatum and substantia nigra of nonlesioned aged rhesus monkeys or young adult rhesus monkeys treated 1 week prior with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Extensive GDNF expression with anterograde and retrograde transport was seen in all animals. In aged monkeys, lenti-GDNF augmented dopaminergic function. In MPTP-treated monkeys, lenti-GDNF reversed functional deficits and completely prevented nigrostriatal degeneration. Additionally, lenti-GDNF injections to intact rhesus monkeys revealed long-term gene expression (8 months). In MPTP-treated monkeys, lenti-GDNF treatment reversed motor deficits in a hand-reach task. These data indicate that GDNF delivery using a lentiviral vector system can prevent nigrostriatal degeneration and induce regeneration in primate models of PD and might be a viable therapeutic strategy for PD patients.  相似文献   

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