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191.
192.
BACKGROUND: This study compared the efficacy of two orally-dosed (PO) anaesthetic regimens for chemical immobilization in rhesus macaques (Macaca mulatta), versus the standard protocol of intramuscular (TM) ketamine. In addition, the effects of dosing route on haematological stress markers were evaluated. METHODS: Testing was conducted on 18 chronically housed animals. Animals were trained to accept oral dosing and then randomly assigned to one of three drug regimens: (1) ketamine IM, (2) ketamine PO, (3) Ketamine/medetomidine PO. Sedation levels for each regimen were evaluated. RESULTS: Oral dosing alone was not sufficient to achieve a plane of sedation that allowed for safe handling. Serum cortisol and glucose levels were unchanged across groups, although differences were observed in the leukogram profiles. CONCLUSION: The oral dosages used in this study fell short in providing adequate sedation for safe handling for routine veterinary procedures. Leukogram profiles indicated that orally dosed animals experienced a higher level of stress. 相似文献
193.
194.
Chakrabarti N Subbarao T Sengupta A Xu F Stouffer RL Sridaran R 《Molecular reproduction and development》2008,75(10):1567-1577
The differential expression of mRNA and protein of GnRH I, II and their receptors (RI and RII) in the monkey corpus luteum (CL) were measured during different stages of the luteal phase of the menstrual cycle as an initial step towards considering the role and regulation of GnRH (I and II) system during luteinization and luteolysis in primates. RT-PCR confirmed the sequence identity of PCR products and real time PCR quantified specific mRNA expressions. Proteins were localized by immunohistochemistry (IHC). Changes in mRNA expression patterns of GnRH I and II (increased) and GnRH RII (decreased) were maximal at mid-late to late stages, that is, at CL regression, where as GnRH RI was low during the entire luteal phase. However, RT-PCR and IHC studies confirmed the presence of GnRH RI at both mRNA and protein levels, respectively. IHC results showed the presence of GnRH I, II and their receptors in steroidogenic cells (granulose-luteal cells and thecal-luteal cells) across the luteal phase. Hence, GnRH I and II systems may have a role on both luteinization (from early to mid stages of CL) and luteolysis (from mid-late to very-late stages of CL). These novel findings suggest that monkey luteal GnRH system may have a role in fertility regulation in paracrine and/or autocrine manner. 相似文献
195.
The family Osmundaceae is among the most primitive ferns of the Filicales, with an extensive fossil record dating back to the Late Paleozoic. Numerous fossil osmundaceous rhizomes have been documented in the geological history. However, the diversity, variation and distribution pattern of permineralized rhizomes remain poorly known. Here we intend to analyze the fossil records with regard to the diversity and distribution pattern of the osmundaceous rhizomes based on available data. To date, about 83 species ascribed to 14 genera of fossil osmundaceous rhizomes have been described worldwide, assigned to two subfamilies, namely, Thamnopteroideae and Osmundoideae. Geologically, two groups (i.e., Thamnopteroideae and Palaeosmunda) have been reported in the Permian. All the Triassic taxa are from the southern hemisphere. Jurassic osmundaceous rhizomes are abundant and widespread throughout the world, most dominant in the southern hemisphere. During the transition of Jurassic to Cretaceous, the diversity of osmundaceous rhizomes declined rapidly. In the Cretaceous, however, the osmundaceous rhizomes from the northern hemisphere surpass those from the southern hemisphere in generic level for the first time. The Cenozoic taxa diversified in the northern hemisphere with the rise of angiosperms. Geographically, the osmundaceous fossil rhizomes have been found in both hemispheres; the major localities include Ural area of the former USSR, Tasmania of Australia, southern Argentina, Antarctica, northern India, central and western part of North America and northern China. We discuss the origin, radiation, and development of the Osmundaceae based on rhizomes, to help further understand the systematic relation and evolutionary history of the family Osmundaceae. 相似文献
196.
Karina Keller Marques da Costa Flaiban Kledir Anderson H. Spohr Luciano de Souza Malanski Walfrido Kühl Svoboda Marcos M. Shiozawa Carmen Lúcia S. Hilst Lucas Moraes Aguiar Gabriela Ludwig Fernando C. Passos Italmar Teodorico Navarro Mara Regina Stipp Balarin Júlio Augusto Naylor Lisbôa 《International journal of primatology》2008,29(5):1375-1382
We evaluated blood samples obtained from 80 free-ranging healthy capuchins (Cebus cay and C. nigritus) to establish hematological reference values and to assess the influence of sex and age on them. We caught the monkeys in
the Paraná River region of Southern Brazil via manual or automatic traps. We anesthetized them intramuscularly with 3.6 mg/kg
tiletamine/zolazepam hydrochlorides. After physical examinations, we divided the sample according to sex and age: 26 females
(13 adults and 13 juveniles) and 54 males (27 adults and 27 juveniles). We collected blood and determined hematological values
via traditional published methods. We analyzed data via 2-way ANOVA to test the effect of sex, age, and interactions between
the 2 factors. The packed-cell volume was higher in adult males and the numbers of white blood cells and lymphocytes were
higher in juveniles. There is no other significant difference. 相似文献
197.
198.
Nicki J. Whitehouse Peter G. Langdon Richard Bustin Sarah Galsworthy 《Biodiversity and Conservation》2008,17(9):2055-2078
We review the uses of fossil insects, particularly Coleoptera (beetles) and Chironomidae (non-biting midges) from ancient
deposits to inform the study of wetland ecosystems and their ecological and restoration processes. In particular, we focus
on two contrasting ecosystems, drawing upon research undertaken by us on British raised mire peats and shallow lake systems,
one an essentially terrestrial ecosystem, the other aquatic, but in which wetland insects play an important and integral part.
The study of raised mire peats suggests that faunal stability is a characteristic of these wetland systems, over what appear
to be extensive periods of time (up to several millennia), whilst studies of shallow lake ecosystems over recent timescales
indicates that faunal instability appears to be more common, usually driven by increasing eutrophication. Drawing upon a series
of fossil Coleoptera records spanning several thousand years from Hatfield Moors, south Yorkshire, we reconstruct in some
detail the mire’s ontogeny and fluctuations in site hydrology and vegetation cover, illustrating the intimate association
between substrate, topography and peat development. A comparison between fossil and modern beetle populations indicates that
the faunal characteristics of this mire and its adjacent neighbour, Thorne Moors, become established during the early phases
of peat development, including its rare endemics, and that the faunal biodiversity on the sites today is dictated by complex
site histories. The over-riding characteristic of these faunas is of stability over several thousand years, which has important
implications for the restoration of degraded sites, especially those where refugial areas are limited. In contrast, analyses
of fossil Chironomidae from shallow lakes allow researchers to track changes in limnological status and while attempts have
been made to reconstruct changes in nutrient levels quantitatively, the chironomids respond indirectly to such changes, typically
mediated through complex ecosystem dynamics such as changes in fish and/or macrophyte communities. These changes are illustrated
via historic chironomid stratigraphies and diversity indices from a range of shallow lakes located across Britain: Slapton
Ley, Frensham Great Pond, Fleet Pond, Kyre Pool and Barnes Loch. These sites have shown varying degrees of eutrophication
over recent timescales which tends to be associated with a decline in chironomid diversity. While complex functional processes
exist within these ecosystems, our evidence suggests that one of the key drivers in the loss of shallow lake chironomid diversity
appears to be the loss of aquatic macrophytes. Overall, while chironomids do show a clear response to altered nutrient regimes,
multi-proxy reconstructions are recommended for a clear interpretation of past change. We conclude that if we are to have
a better understanding of biota at the ecosystem level we need to know more of the complex interactions between different
insect groups as well as with other animal and plant communities. A palaeoecological approach is thus crucial in order to
assess the role of insect groups in ecosystem processes, both in the recent past and over long time scales, and is essential
for wetland managers and conservation organisations involved in long term management and restoration of wetland systems 相似文献
199.
Primate copulation calls and postcopulatory female choice 总被引:2,自引:0,他引:2
Females in some species of Old World monkeys and apes vocalizeafter copulation, but the function of these vocalizations isnot clear. In this article, we examine the hypothesis that copulationcalls are a form of postcopulatory female choice. Accordingto this hypothesis, copulation calls are honest signals of fertility(i.e., ovulation) that are used by females to encourage mateguarding by their preferred mating partners and reduce the likelihoodof sperm competition. Evidence in favor of this hypothesis isreviewed and discussed in relation to other hypotheses. We suggestthat the evolution of female copulation calls in primates islinked to the evolution of other female mating signals suchas exaggerated sexual swellings, the potential for sperm competition,and the opportunity for precopulatory female mate choice. 相似文献
200.
Yves Rumpler 《Evolutionary anthropology》2004,13(2):67-78
The lemurs, prosimian primates of Madagascar, constitute a zoological group containing numerous species and subspecies. Their taxonomy remains controversial. Depending on the authors and the techniques they have used, the number of species varies between 39 and 52. In addition, although a monophyletic origin of the settlement of Madagascar is the most commonly held opinion, recent studies based on molecular biology do not exclude two independent colonization events, one involving Daubentonia and a second giving rise to the other lemurs. 1 . 相似文献