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The expression of the epitope detected by the monoclonal antibody Leu-5 and the rosette formation with sheep red blood cells was examined for the mononuclear cells of 25 primate species including human subject. The plot of rosette-forming cells against Leu-5-positive cells enabled us to classify these species into three large groups: hominoids--Old World monkeys (Leu-5-positive cells greater than or equal to rosette-forming cells), New World monkeys (Leu-5-positive cells less than rosette-forming cells), and prosimians (Leu-5-positive cells less than 5%, some of them with both Leu-5-positive cells and rosette-forming cells less than 5%).  相似文献   

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Animal experimentation contributes significantly to the progression of science. Nonhuman primates play a particularly important role in biomedical research not only because of their anatomical, physiological, biochemical, and behavioral similarities with humans but also because of their close phylogenetic affinities. In order to investigate the use of New World primates (NWP) in biomedical research over the last four decades (1966–2005), we performed a quantitative study of the literature listed in bibliographic databases from the Health Sciences. The survey was performed for each genus of NWP that has been bred in the National Center of Primates in Brazil. The number of articles published was determined for each genus and sorted according to the country from which the studies originated and the general scientific field. The data obtained suggests that Brazil is a leader in generating knowledge with NWP models for translational medicine. Am. J. Primatol. 72:1055–1061, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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Despite over 25 years of intensive research, much of our knowledge of primate behavior has been limited to a small number of Old World, semiterrestrial species. With the exception of chimpanzees, these species share consistent patterns of behavior, including aggressive competition between males, male dominance over females, male dispersal and female kin groups, that have come to characterize the Order Primates. However, as research has expanded to include a number of newly studied species, such generalizations about primate behavior are no longer appropriate. Data presented on the wooly spider monkey, or muriqui (Brachyteles arachnoides), provide examples of the ways in which traditional views of primate behavior are being reconsidered. In muriquis, and in several other New World monkeys, female kin groups do not occur because females disperse from their natal groups. In addition, aggressive competition between males is virtually absent; and, female muriquis appear to be codominant with males. Constraints on sexual dimorphism may help to explain why muriquis (and other New World primates) differ so fundamentally from the better known semi-terrestrial Old World monkeys.Logo of the 1988 International Primatological Society.  相似文献   

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Patterns of three variables of reproductive strategies in male New World primates are examined: (i) how males obtain access to potential mates; (ii) how males obtain actual mating opportunities; and (iii) how males affect infant survival and female reproductive success. Male opportunities to associate with females, whether by remaining in their natal groups, dispersing and forming new groups, or dispersing and taking over or joining established groups, are strongly influenced by local population densities and correlate with female reproductive rates and the extent of female reproductive seasonality and synchrony. Differences in male mating success are affected by female accessibility, whether male-male and male-female relationships are hierarchical or egalitarian, and whether female reproduction is seasonally restricted. Patterns of male behavior toward infants, characterized as active assistance, overt interference, or benign tolerance, appear to co-vary with differences in the degree to which males can affect female reproductive rates. These qualitative analyses suggest that the reproductive strategies of male New World primates can be classified along a continuum ranging from conservative to daring depending on whether female reproductive rates are relatively slow or fast and whether reproduction is strongly or weakly linked to seasonal ecological variables. Males adopt the conservative strategy of staying in their natal groups, forfeiting exclusive mating opportunities, and treating infants with tolerance when female reproduction is constrained by ecological factors. Conversely, males adopt the more daring strategy of dispersing and competing when potential payoffs through their ability to affect female reproduction are high.  相似文献   

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Until the last decade or so, relatively little was known of cranial asymmetries in nonhuman primates. Data are slowly, but surely, accumulating for such features as transverse sinus flow, sylvian point angle differences, external brain morphology, etc. Cranial asymmetries are being analyzed and related to such diverse problems as “handedness” and phylogenetic systematics. It has been known for over 200 years that cranial asymmetry exists in some of the cerebral blood flow patterns in man, particularly the internal jugular pathway. Although earlier anatomists assumed this was only characteristic of “higher primates” (meaning man and the great apes), little quantitative data have been available to either support or deny this belief. There is a particular dearth of information for New World primates. The aim of this study is to contribute to the growing literature on cerebral asymmetries by partially filling in this gap in our knowledge of New World primate biology.  相似文献   

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About 50 species in more than 20 genera of the microdrile oligochaete families Tubificidae, Naididae, Opistocystidae, and Enchytraeidae and the freshwater megadrile families Sparganophilidae and Alluroididae were identified in recent collections made in Guyana. Only seven species in these families were previously recorded from Guyana. The aquatic oligochaete fauna has similar components to those of the southeastern United States, other locations in South America, and across lower latitudes in the northern hemisphere. A high diversity of species is found in the naidids especially in the genera Pristina and Pristinella, especially considering the small number of locations that have been sampled. The collections include approximately 12 new species of rhyacodrilines (Tubificidae), Dero, Pristina, Pristinella (Naididae), Brinkhurstia (Alluroididae), Hemienchytraeus and Aspidodrilus (Enchytraeidae). This is the first record of Aspidodrilus from outside of Africa and the first new record since 1952.  相似文献   

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Abstract

More than half a century ago, Percy Butler touted the importance of analyzing teeth to understand their function in an evolutionary context. There have been many advances in the study of dental functional morphology since that time. Here we review the various approaches to characterizing and comparing occlusal form that have been developed, especially dental topographic analysis. We also report on a new study of dental topography of platyrrhine primates (n = 341 individuals representing 16 species) with known differences in both dietary preferences and other food items eaten. Results indicate frugivores, gummivores, folivores, and seed eaters each have a unique combination of slope, relief, angularity, sharpness, and occlusal orientation patch size and count values. Likewise, among frugivores, those that supplement their diets with hard objects, insects, leaves, and seeds, also each have a distinctive suite of topographic features. We conclude that both primary and secondary diet choices select for occlusal form, and that functional morphology more reflects the types of foods and mechanical challenges they pose rather than the frequencies in which they are eaten.  相似文献   

10.
Abstract: Development as well as current status of the knowledge of nonhuman primate blood groups are discussed together with some practical implications of the red cell antigen polymorphisms in anthropoid apes, Old and New World monkeys and prosimians. Recent data on molecular biology and genetics throw light on the relationships among simian and human red cell antigens and their evolutionary pathways.  相似文献   

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A comparison of the distribution of brain monoamine neurons in several New World and Old World monkeys was undertaken using the Falck-Hillarp formaldehyde histofluorescence technique. The overall organization of the monoamine neurons was very similar in all species, although subtle variations were found. Catecholamine (noradrenaline and dopamine) and indoleamine (serotonin) cell bodies corresponding to groups A1–A7, A8–A10, and B1–B9, respectively were found throughout the brainstem. A few catecholamine (dopamine) cells equivalent to groups All and A12 in the diencephalon were also observed. Noradrenaline neurons, rather than those of the dopamine and serotonin systems, tended to be less numerous in the New World monkeys. Ascending catecholamine and indoleamine fiber bundles were observed in most monkeys. It is interesting that fibers corresponding to the “ventral noradrenaline bundle” appeared to be much finer in the common marmoset and tamarin than in other species. In addition, a substantial catecholamine (noradrenaline) innervation of the diencephalon was noted in all the Old World monkeys, while a much lower overall terminal density was apparent in the New World forms.  相似文献   

14.
Job Kuijt 《Brittonia》2003,55(2):169-172
A new species ofOryctina (Loranthaceae) from Guyana,O. atrolineata Kuijt is described and illustrated. It possesses one-flowered inflorescences, the flowers being hexamerous and each subtended by a bract and two minute bracteoles. A peculiarity of the style is a distinctive fusiform, subterminal swelling.Oryctina atrolineata is closely related, and similar to,O. myrsinites (Eichler) Kuijt.  相似文献   

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Studies of primate community structure increase our understanding of behavior, adaptation, and evolution. However, there are few biogeographic data on specific composition and association patterns in primate communities. I conducted a biogeographic analysis of the community structure of primate species at 16 sites in Guyana. I used data from 1725 km of line-transect censuses to determine specific composition and association patterns of 220 primate groups . Of the 18 polyspecific groups, 94.1% (N = 16) included squirrel monkeys. There was an overall trend towards positive specific associations among Guyanese primates. The only species that exhibited a negative pattern of interspecific associations were brown and wedge-capped capuchins. The sighting rate for wedge-capped capuchins at sympatric sites was particularly depressed compared to that for brown capuchins. Low plant productivity in Guyanese forests may reduce the diversity of feeding niches and result in a low incidence of polyspecific associations and scramble competition between wedge-capped and brown capuchins.  相似文献   

17.
This study presents an experimental approach to measure the density distribution of expanded bed adsorption (EBA) matrices. We report on the use of a series of solutions of caesium trifluoroacetate (CsTFA) of varying density spun in a laboratory centrifuge so as to separate representative matrix samples on the basis of bead density. Mass data was used to plot a decumulative density distribution for the matrix. By performing laser light scattering-based measurements on the same samples of matrix the variation in particle size with density was determined. Particle settling velocity distributions were then calculated using these data and compared with a settling velocity distribution calculated on the basis of an assumed constant bead density. The study demonstrates a reliable and simple method for the characterisation of matrix density distribution. For the case of the Streamline matrices tested the particle size distribution is constant with varying bead density. Bead densities varied from 1.5 to 2.1 g/cm3 in the CsTFA solutions. These were then adjusted using bead porosity to give a density range of 1.11-1.33 g/cm3 in aqueous buffer (assumed 1.0 g/cm3) The differences in resultant settling velocity distributions when based upon measured density distribution than when based upon an assumed mean density value were shown to be insignificant. This result confirms experimentally that an assumption of a single constant mean density for EBA particles is acceptable for hydrodynamic modelling and performance prediction purposes.  相似文献   

18.
Hybridization is continually documented in primates, but effects of natural and anthropogenic hybridization on biodiversity are still unclear and differentiating between these contexts remains challenging in regards to primate evolution and conservation. Here, we examine hybridization effects on the mitochondrial DNA (mtDNA) control region of Callithrix marmosets, which provide a unique glimpse into interspecific mating under distinct anthropogenic and natural conditions. DNA was sampled from 40 marmosets along a 50‐km transect from a previously uncharacterized hybrid zone in NE Brazil between the ranges of Callithrix jacchus and Callithrix penicillata. DNA was also collected from 46 marmosets along a 30‐km transect in a hybrid zone in Rio de Janeiro state, Brazil, where exotic marmosets appeared in the 1980s. Combining Callithrix DNA sampled inside and outside of these hybrid zones, phylogenetic and network analyses show C. jacchus and C. penicillata being parental species to sampled hybrids. We expand limited Callithrix population genetics work by describing mtDNA diversity and demographic history of these parental species. We show ancient population expansion in C. jacchus and historically constant population size in C. penicillata, with the latter being more genetically diverse than the former. The natural hybrid zone contained higher genetic diversity relative to the anthropogenic zone. While our data suggest hybrid swarm formation within the anthropogenic zone due to removed physical reproductive barriers, this pattern is not seen in the natural hybrid zone. These results suggest different genetic dynamics within natural and anthropogenic hybridization contexts that carry important implications for primate evolution and conservation. Am J Phys Anthropol 155:522–536, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

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While a goal of many field primatologists is to observe subjects in as undisturbed a setting as possible, it is often necessary to anesthetize animals for any of a variety of reasons. In this paper, we review techniques for anesthetizing wild primates, based on our experience with more than a thousand such procedures carried out on baboons in East Africa. We consider the following: 1) rationales for anesthetizing a wild primate; 2) systems for the delivery of anesthetic and choice of anesthetic; 3) the darting process itself and issues relevant to the period between darting and the safe removal of the animal; 4) handling of an anesthetized primate; 5) medical complications associated with darting; 6) when to reanesthetize an animal; 7) the process of recovery from anesthesia and release of an awake animal; 8) safety issues for humans. The range of information that can be obtained through field anesthetizations, when carried out successfully, as well as the potential benefit for the animals involved, can be enormous. However, this process is not trivial from the standpoint of the dangers involved to both the subjects and to humans and because of the potential disruption of social behavior to the group. As such, anesthetizations in the field should not be carried out without a strong rationale and without a tremendous priority given to the safety and care of all involved. Am. J. Primatol. 44:155–167, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

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This study examines the use levonorgestrel (Norplant®‐2) as a means of contracepting white‐faced sakis (Pithecia pithecia). A 70‐mg silastic tubule of levonorgestrel was implanted subdermally between the scapulae in four multiparous and two nulliparous females. Implants remained in the females housed with males of proven fertility for 81 to 734 days. All females experienced low, acyclic levels of estrone conjugates (E1C, < 500 ng/mg Cr) and pregnanediol‐3‐glucuronide (PdG, < 1.5 μg/mg Cr) after insertion of the implant. In five females having nine contraceptive bouts, ovulation was completely blocked for the entire duration of Norplant insertion (range: 81–734 days) as evidenced by a lack of cyclic changes in excretory hormone levels. However, one female was observed to have cyclic ovarian hormonal levels 5.8 months after Norplant insertion. Thus, levonorgestrel can be an effective method for blocking cyclic ovarian hormonal changes for 1 year (n = 2) and possibly as long as 2 years (n = 3). Zoo Biol 21:49–57, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   

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