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71.
Schrenzel MD Osborn KG Shima A Klieforth RB Maalouf GA 《Journal of medical primatology》2003,32(1):7-14
A family of three white-faced saki monkeys (Pithecia pithecia pithecia) died 48-96 hours after the onset of anorexia, nasal discharge, pyrexia and oral ulceration. One animal also had clonic seizures. Lesions found post-mortem consisted of oral and esophageal ulcers, hepatic and intestinal necrosis, meningoencephalitis and sporadic neuronal necrosis. Intranuclear inclusion bodies and syncytial cells were present in oral lesions and affected areas of liver. Herpes simplex virus 1 (HSV-1) was identified as the etiology of disease by virus isolation, polymerase chain reaction, or in situ hybridization in all three animals. Immunohistochemistry for detection of apoptotic DNA and activated caspase-3 showed significant levels of apoptosis in oral and liver lesions and occasional apoptotic neurons in the brain. These findings demonstrate the vulnerability of white-faced saki monkeys to HSV-1 and provide initial insight into the pathogenesis of fatal HSV-1-induced disease, indicating that apoptosis plays a significant role in cell death. 相似文献
72.
Susan G. Larson 《American journal of physical anthropology》1984,64(1):59-67
The importance of allometry as an analytic tool is well recognized in the literature of primate morphology. However, a number of recent studies have illustrated how interpretive difficulties can arise when researchers confound different types of allometric data. Such confusion is due less to carelessness than to uncertainty about how different types of allometry are related. The present study examines the relationship between two types—ontogenetic and interspecific allometry–in the case of organ weight scaling in six species of Old World monkeys. Accepting the interpretation of interspecific allometry as a reflection of functional scaling constraints, the results of this analysis indicate how ontogenetic patterns have been modified in different-sized species to maintain compliance with these constraints. Specifically, for the heart and lungs it appears that vertical transpositions of individual species' ontogenies are dictated by isometric interspecific allometry, while in the case of the kidneys and liver, the relation of negative allometry across species entails alteration of the relative growth coefficients of the individual species. While these conclusions can at present only be applied to organ weight scaling, the approach of examining interspecific patterns in light of developmental differences between species should prove very helpful in our efforts to understand the phenomena of size and scaling. 相似文献
73.
74.
Chloroplast DNA restriction site variation was examined for 35 taxa in theVernonieae and four outgroup tribes, using 17 restriction enzymes mapped for ca. 900 restriction sites per species; 139 mutations were found to be phylogenetically informative. Phylogenetic trees were constructed using Wagner and weighted parsimony, and evaluated by bootstrap and decay analyses. Relationships of Old and New World taxa indicate complex geographical relationships; there was no clear geographic separation by hemisphere. The relationships between Old and New World Vernonias found here support prior morphological analyses. The sister group to all New and most Old World taxa was composed of a small group of Old World species including yellow-flowered, trinervate-leaved species previously postulated to be basal in the tribe. The majority of both New and Old World taxa are derived from a lineage beginning with the monotypic genusStokesia, an endemic of the southeastern United States. The genusVernonia was also found to be paraphyletic within both the New and Old World. Available data do not support either the separation ofVernonia or the tribeVernonieae into geographically distinct lineages. The pattern of relationships within theVernonieae for taxa from North America, Asia, Africa, Central and South America is most similar to that of several other groups of both plants and animals with a boreotropical origin, rather than an origin in Gondwanaland. Such a pattern of distribution suggests more ancient vicariant events than are routinely postulated for theAsteraceae. 相似文献
75.
M. Pickford 《Human Evolution》1987,2(1):71-89
The synoptic perspective of the fossil record of Old World monkeys presented in the preceding articles prompted the author
to explore aspects of cercopithecid biology which are difficult to examine with parochial evidence. These aspects include
origins and subsequent spread of monkeys through the Old World, relationship of major events in cercopithecoid history to
global climatic history, zoogeography and palaeozoogeography, and comparison of palaentological and neontological versions
of cercopithecid phylogenies. While there remain temporal and geographic gaps in the fossil record, difficulties in interpretations
will persist, but for the cercopithecids, the fossil data base is sufficiently comprehensive to yield a view of several of
the main events in their history. 相似文献
76.
Bernadine D. Metzinger Charles M. Taliaferro Becky B. Johnson Earl D. Mitchell Jr. 《Plant Cell, Tissue and Organ Culture》1987,10(1):31-38
Explants from immature inflorescences of four genotypes of Old World bluestem grasses, (Bothriochloa spp.), produced callus tissue on Linsmaier and Skoog (RM) and 1/2 Murashige and Skoog (1/2 MS) media containing high levels of growth regulators. Callus masses were composed of two distinct tissue types, one a compact, white, embryogenic portion (E calli), the other soft, translucent, gelatinous and nonembryogenic (NE calli). When transferred to medium with a reduced level of 2,4-D, and/or supplemented with zeatin, E callus underwent further organization culminating in shoot production. Light and scanning electron microscopy confirmed the embryogenic pathway of differentiation. Genotype significantly affected callus induction frequency and the number of plants regenerated. The RM medium induced more explants to initiate callus compared to the 1/2 MS medium. Age of the inflorescence explant, as indicated by size, was critical for callus induction. Inflorescences with racemes 8 mm in length were superior to older ones. Five-hundred-twenty-two plantlets were regenerated and grown to maturity. 相似文献
77.
Systematic revision of the genus Steginoporella: until now about eighty species were described. Only twenty recent species and thirty-four fossil ones are maintained. Several species and subspecies are new.The main interest of this revision is to establish a biostratigraphical scale: the settlement of this scale is based on the known stratigraphical distribution and on an attempt of phylogeny.The second advantage is ecological: all recent species live in marine tropical environment. The Steginoporella are good paleoecological indicators.At last, the establishment of a paleobiogeography, even incomplete and not definitive, allows to understand more easily recent distribution of Steginoporella connected with the great events of earth evolution. 相似文献
78.
The extent to which response to environmental change is mediated by species-specific ecology is an important aspect of the population histories of tropical taxa. During the Pleistocene glacial cycles and associated sea level fluctuations, the Sunda region in Southeast Asia experienced concurrent changes in landmass area and the ratio of forest to open habitat, providing an ideal setting to test the expectation that habitat associations played an important role in determining species' response to the opportunity for geographic expansion. We used mitochondrial control region sequences and six microsatellite loci to compare the phylogeographic structure and demographic histories of four broadly sympatric species of Old World fruit bats in the genus, Cynopterus. Two forest-associated species and two open-habitat generalists were sampled along a latitudinal transect in Singapore, peninsular Malaysia, and southern Thailand. Contrary to expectations based on habitat associations, the geographic scale of population structure was not concordant across ecologically similar species. We found evidence for long and relatively stable demographic history in one forest and one open-habitat species, and inferred non-coincident demographic expansions in the second forest and open-habitat species. Thus, while these results indicate that Pleistocene climate change did not have a single effect on population structure across species, a correlation between habitat association and response to environmental change was supported in only two of four species. We conclude that interactions between multiple factors, including historical and contemporary environmental change, species-specific ecology and interspecific interactions, have shaped the recent evolutionary histories of Cynopterus fruit bats in Southeast Asia. 相似文献
79.
This study investigates prehension in 20 tufted capuchins (Cebus apella) in a reaching task requiring individuals to grasp a small food item fixed to a tray. The aim was twofold: 1) to describe capuchins' grasping techniques in detail, focusing on digit movements and on different areas of contact between the grasping fingers; and 2) to assess the relationship between grip types and manual laterality in this species. Capuchins picked up small food items using a wide variety of grips. In particular, 16 precision grip variants and 4 power grip variants were identified. The most frequently used precision grip involved the distal lateral areas of the thumb and the index finger, while the most preferred kind of power grip involved the thumb and the palm, with the thumb being enclosed by the other fingers. Immature capuchins picked up small food items using power grips more often than precision grips, while adult individuals exhibited no significant preference for either grip type. The analysis performed on the time capuchins took to grasp the food and withdraw it from the tray hole revealed that 1) precision grips were as efficient as power grips; 2) for precision grips, the left hand was faster than the right hand; and 3) for power grips, both hands were equally quick. Hand preference analysis, based on the frequency for the use of either hand for grasping actions, revealed no significant hand bias at group level. Likewise, there was no significant relationship between grip type and hand preference. 相似文献
80.
有关《植物园学》问题的讨论 总被引:9,自引:0,他引:9
讨论了世界及我国植物园的建立、发展及近代植物园的性质与任务.本文第一作者曾指出中国科学院下属植物园的建立、建设和以科研为先导,推动科普与生产等工作,可以概括为一新兴的、综合性的学科--植物系统与工程学,或称新植物园学.并对中国科学院下属植物园科研、科普、建园、生产等作过论述.另外指出中国植物园与发达国家植物园之间的差距在于中国植物园的体制、管理机制、经济支撑与高素质的科技人才的努力工作精神.同时中国植物园信息研究、管理与交流滞后;在园貌建设方面,中国植物园与发达国家植物园相比,缺乏中国经典的建筑群与雕塑群,也缺少具中国特色的"师出自然"的造园手法与造林中的"适地适树"的有机结合等.过去提出植物园主要任务是植物引种驯化,即"从种子到种子".作者认为过分强调"从种子到种子"有其"误区".对园艺花卉、蔬菜及观叶植物而言,只需能长好叶或开好花,能批量生产、快速繁殖出来满足市场需要就是成果,而无需考虑种子的出处,或种子的有或无.原产中国多种杨树及柳树种子生育力已极度退化,原产地都难以"从种子到种子",但却是速生、无性繁殖力极强的树种.而若干有害杂草,如紫茎泽兰、薇苷菊、凤眼莲等从国外传入中国,无须"驯化"、却极容易"从种子到种子"的快速地繁衍,造成大面积的灾害.最后,作者强调发挥植物园作为植物大世界网上星罗棋布的一个闪亮发光的亮点的作用,加强信息研究、交流与传导工作,尤其在当今"知识创新工程"和新的"绿色革命"的浪潮的推动下,代表21世纪的新的技术革命的"纳米技术"与生物学的结合以及作为信息时代的信息研究与流通更显得必要. 相似文献