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1.
In recent years, more and more laboratories have developed functional Magnetic Resonance Imaging (fMRI) for awake non-human primates. This research is essential to provide a link between non-invasive hemodynamic signals recorded in the human brain and the vast body of knowledge gained from invasive electrophysiological studies in monkeys. Given that their brain structure is so closely related to that of humans and that monkeys can be trained to perform complicated behavioral tasks, results obtained with monkey fMRI and electrophysiology can be compared to fMRI results obtained in humans, and provide information crucial to a better understanding of the mechanisms by which different cortical areas perform their functions in the human brain. However, despite that the first publications on fMRI in awake behaving macaques appeared ~10 years ago (Logothetis et al. (1999) [1], Stefanacci et al. (1998) [2], Dubowitz et al. (1998) [3]), relatively few laboratories perform such experiments routinely, a sign of the significant technical difficulties that must be overcome. The higher spatial resolution required because of the animal’s smaller brain results in poorer signal-to-noise ratios than in human fMRI, which is further compounded by problems due to animal motion. Here, we discuss the specific challenges and benefits of fMRI in the awake monkey and review the methodologies and strategies for scanning behaving macaques.  相似文献   

2.
The giraffe restraint device manufactured at the Cheyenne Mountain Zoo has the capability to fully support the weight of an immobilized adult giraffe in an upright posture and allow physical restraint of giraffe. The unit has been used for either chemical or physical restraint 74 times, in 22 months, on seven different adult giraffe, without animal or personnel injuries. Habituation and desensitization of the giraffe are critical prerequisites for the successful use of the giraffe restraint device. Yohimbine effectively reversed the effects of xylazine sedation of giraffe. A drug combination of detomidine and azaperone offers promise as an alternative to either physical restraint or immobilization of giraffe for selected clinical and investigative procedures. Using the restraint device it has been possible to perform tuberculin testing, venipuncture, vaginal examination, rectal palpation, rectal ultrasound, cervical catheterization, hoof-trimming, and placement of a hoof block on awake, habituated, and desensitized giraffe.  相似文献   

3.
Free-ranging animals often cope with fluctuating environmental conditions such as weather, food availability, predation risk, the requirements of breeding, and the influence of anthropogenic factors. Consequently, researchers are increasingly measuring stress markers, especially glucocorticoids, to understand stress, disturbance, and population health. Studying free-ranging animals, however, comes with numerous difficulties posed by environmental conditions and the particular characteristics of study species. Performing measurements under either physical restraint or chemical sedation may affect the physiological variable under investigation and lead to values that may not reflect the standard functional state of the animal. This study measured the stress response resulting from different handling conditions in northern elephant seals and any ensuing influences on carbohydrate metabolism. Endogenous glucose production (EGP) was measured using [6-(3)H]glucose and plasma cortisol concentration was measured from blood samples drawn during three-hour measurement intervals. These measurements were conducted in weanlings and yearlings with and without the use of chemical sedatives--under chemical sedation, physical restraint, or unrestrained. We compared these findings with measurements in adult seals sedated in the field. The method of handling had a significant influence on the stress response and carbohydrate metabolism. Physically restrained weanlings and yearlings transported to the lab had increased concentrations of circulating cortisol (F(11, 46)?=?25.2, p<0.01) and epinephrine (F(3, 12)?=?5.8, p?=?0.01). Physical restraint led to increased EGP (t?=?3.1, p?=?0.04) and elevated plasma glucose levels (t?=?8.2, p<0.01). Animals chemically sedated in the field typically did not exhibit a cortisol stress response. The combination of anesthetic agents (Telazol, ketamine, and diazepam) used in this study appeared to alleviate a cortisol stress response due to handling in the field without altering carbohydrate metabolism. Measures of hormone concentrations and metabolism made under these conditions are more likely to reflect basal values.  相似文献   

4.
Assessment of the Diversity of African Primates   总被引:13,自引:9,他引:4  
This account of the systematics of African primates is the consensus view of a group of authors who attended the Workshop of the IUCN/SSC Primate Specialist Group held at Orlando, Florida, in February 2000. We list all species and subspecies that we consider to be valid, together with a selected synonymy for all names that have been controversial in recent years or that have been considered to be valid by other authors in recent publications. For genera, species-groups or species, we tabulate and discuss different published systematic interpretations, with emphasis on more recent publications. We explain why we have adopted our taxonomic treatment and give particular attention to cases where more research is urgently required and in which systematic changes are most likely to be made. For all taxa, from suborder to subspecies, we provide English names.  相似文献   

5.
Neural correlates of social target value in macaque parietal cortex   总被引:1,自引:0,他引:1  
Animals as diverse as arthropods [1], fish [2], reptiles [3], birds [4], and mammals, including primates [5], depend on visually acquired information about conspecifics for survival and reproduction. For example, mate localization often relies on vision [6], and visual cues frequently advertise sexual receptivity or phenotypic quality [5]. Moreover, recognizing previously encountered competitors or individuals with preestablished territories [7] or dominance status [1, 5] can eliminate the need for confrontation and the associated energetic expense and risk for injury. Furthermore, primates, including humans, tend to look toward conspecifics and objects of their attention [8, 9], and male monkeys will forego juice rewards to view images of high-ranking males and female genitalia [10]. Despite these observations, we know little about how the brain evaluates social information or uses this appraisal to guide behavior. Here, we show that neurons in the primate lateral intraparietal area (LIP), a cortical area previously linked to attention and saccade planning [11, 12], signal the value of social information when this assessment influences orienting decisions. In contrast, social expectations had no impact on LIP neuron activity when monkeys were not required to make a choice. These results demonstrate for the first time that parietal cortex carries abstract, modality-independent target value signals that inform the choice of where to look.  相似文献   

6.
Oligosaccharides of milk and colostrum in non-human mammals   总被引:3,自引:0,他引:3  
Mammalian milk or colostrum usually contains, in addition to lactose, a variety of neutral and acidic oligosaccharides. Although the oligosaccharides of human milk have been reviewed in several recent publications, those of non-human mammals have received much less attention. This paper reviews the chemical structures and the variety of milk oligosaccharides in species other than humans, including placental mammals (e.g. primates, domestic herbivores, bears and other carnivores, the rat and the elephant) as well as monotremes (platypus and echidna) and marsupials (e.g. wallaby). The gastrointestinal digestion and absorption and the possible biological functions of these oligosaccharides are also discussed.  相似文献   

7.
We describe a novel soft jacket and sling-harness restraint that permits species-typical postures for small-bodied primates, such as the common marmoset (Callithrix jacchus), during long-term (>6 h), continuous restraint. The restraint system is straightforward to use and manipulate, it is easily repaired, and the materials used are readily available. The soft jacket allows for increased versatility and longevity, and the sling-harness provides for greater movement and much longer duration of continuous restraint (up to 3 days) compared to a previously described, more conventional chair restraint for small-bodied primates. The new restraint system prevents the normal diurnal decrease in plasma cortisol levels across the daylight hours; however, it does not disrupt ovulatory cycles. Unlike the previously available techniques, therefore, this new restraint system is applicable to many neurobiological and neuroendocrine studies involving small-bodied, non-human primates and is especially suited to investigations requiring the maintenance of relationships within social groups.  相似文献   

8.
This study surveyed 33 male hunters between the ages of 17 and 54 at the Community Baboon Sanctuary (CBS), Belize, to evaluate attitudes and behaviors in relation to hunting black howler monkeys (Alouatta pigra). The study defined hunting restraint as a learned predisposition not to hunt 1 or more species of nonhuman animal. Consistent with Belizean folklore, Creoles at the CBS exhibited hunting restraint with respect to black howlers, preferring to kill bushmeat other than monkeys. The most cited reasons for the observed hunting restraint were utilitarian. Historical and cultural factors also appeared significant. The study results are interpreted in terms of economic theory and suggest that disinhibition of hunting restraint might depend on changes in opportunity costs of hunting these primates. Nonetheless, a change in hunting attitudes and behaviors by Belizean Creoles seems unlikely in the near future because the local and national government and the benefits of ecotourism economically and legally protect howlers. The Creoles' culturally transmitted hunting restraint also culturally protects A. pigra, and the species is not a preferred source of food.  相似文献   

9.
Background Streptozotocin‐induced diabetic non‐human primates are used to study efficacy and safety of innovative immunosuppression after islet transplantation. We implemented a training program for medical management of a chronic disease state. Methods Cooperation with hand feeding and drinking, shifting, and limb presentation were trained utilizing predominately positive but also negative reinforcement in 52 animals compared with 28 macaques subjected to conventional physical and/or chemical restraint. The success and timing of behavior acquisition was evaluated in a representative subset of 14 animals. Results Over 90% of animals were successful in behavior acquisition. Programmatically this resulted in complete elimination of chair restraint and negligible requirement for sedation. About half of the trained animals had no‐to‐moderate thymic involution, indicative of a substantial reduction in stress. Conclusion Cooperative handling enhances animal well‐being. This contributes to validity of scientific results and eliminates model‐induced confounding that can obstruct interpretation of safety and efficacy data.  相似文献   

10.
《Anthrozo?s》2013,26(3):288-303
Abstract

Laboratory-housed non-human primates may experience a range of potential stressors, including physical and chemical restraint, venepuncture, injection, catching and cage-change. Training them to co-operate, using positive reinforcement techniques, is one means of significantly reducing the adverse impact of such procedures upon them and, therefore, is a refinement. Furthermore, the additional time that staff spend with the primates, and the need for individual recognition and close observation of animal behavior, mean that the trainer develops a relationship with each individual animal which can be beneficial for animal welfare (e.g., by reducing the occurrence of abnormal behavior and fear of humans). We surveyed use of training in thirteen UK establishments using and breeding primates, utilizing a mixed-mode questionnaire. The survey demonstrated that there is widespread awareness of training as a refinement and appreciation of its diverse benefits, but training is not used as widely or as fully as it might be. This is largely due to real constraints (principally staff and time and a lack of confidence in ability to train), and perceived constraints (such as a supposed lack of information on how to train and assessment of the benefits, and an overestimation of the time investment needed). There is also considerable variation between establishments in the purposes of training and techniques used, with a reliance on negative reinforcement in three. We conclude that there is considerable scope for refinement of common scientific, veterinary and husbandry procedures, and refer to some resources designed to help establishments take action (e.g., Prescott and Buchanan-Smith 2003).  相似文献   

11.
Infrared and Raman spectra of sequentially extracted primary cell walls and their pectic polymers were obtained from five angiosperm plants. Fourier-transform Raman spectrometry was shown to be a powerful tool for the investigation of primary cell-wall architecture at a molecular level, providing complementary information to that obtained by Fourier-transform infrared microspectroscopy. The use of an extraction procedure using imidazole instead of cyclohexane trans-1,2-N,N,N[prime],N[prime]-diaminotetraacetate allows the extension of the infrared spectral window for data interpretation from 1300 to 800 cm-1, to 2000 to 800 cm-1, and allows us to obtain Raman spectra from extracted cell-wall material. Wall constituents such as pectins, proteins, aromatic phenolics, cellulose, and hemicellulose have characteristic spectral features that can be used to identify and/or fingerprint these polymers without, in most cases, the need for any physical separation. The Gramineae (rice [Oryza sativa], polypogon [Polypogon fugax steud], and sweet corn [Zea mays]) are spectroscopically very different from the nongraminaceous monocotyledon (onion [Allium cepa]) and the dicotyledon (carrot [Daucus carota]); this reflects differences in chemical composition and cross-linking of the walls. The possibility of a taxonomic classification of plant cell walls based on infrared and Raman spectroscopies and the use of spectral fingerprinting for authentication and detection of adulteration of products rich in cell-wall materials are discussed.  相似文献   

12.
Since 1985, when a bibliography concerning studies on surnames and genetic structure appeared, the number of publications on this subject has increased a thousandfold. New topics and uses have been added, but large gaps in knowledge remain. Only studies on isonymy in cities of nation states for recent times are well covered, and most studies are on populations that were selected because they are isolated and not because they are typical. This review, although not exhaustive, covers the literature published since 1985.  相似文献   

13.
Recent publications dealing with nonhuman primate social behavior suggest that Service's discussion of that topic in The Hunters is in need of extensive revision, and that Damas's (AA 71:315–316) recently expressed admiration for the discussion is unfortunate. Short paragraphs based on readily available references summarize findings that have appeared since The Hunters was published and indicate where Service's generalizations concerning species specific social organization, sexual seasonality, dominance orders, and territoriality are in greatest need of updating. [Primate social behavior; hunter-gatherers; ecological studies]  相似文献   

14.
Enzymes that activate dioxygen at carboxylate-bridged non-heme diiron clusters residing within ferritin-like, four-helix-bundle protein architectures have crucial roles in, among other processes, the global carbon cycle (e.g. soluble methane monooxygenase), fatty acid biosynthesis [plant fatty acyl-acyl carrier protein (ACP) desaturases], DNA biosynthesis [the R2 or β2 subunits of class Ia ribonucleotide reductases (RNRs)], and cellular iron trafficking (ferritins). Classic studies on class Ia RNRs showed long ago how this obligatorily oxidative di-iron/O2 chemistry can be used to activate an enzyme for even a reduction reaction, and more recent investigations of class Ib and Ic RNRs, coupled with earlier studies on dimanganese catalases, have shown that members of this protein family can also incorporate either one or two Mn ions and use them in place of iron for redox catalysis. These two strategies--oxidative activation for non-oxidative reactions and use of alternative metal ions--expand the catalytic repertoire of the family, probably to include activities that remain to be discovered. Indeed, a recent study has suggested that fatty aldehyde decarbonylases (ADs) from cyanobacteria, purported to catalyze a redox-neutral cleavage of a Cn aldehyde to the Cn-1 alkane (or alkene) and CO, also belong to this enzyme family and are most similar in structure to two other members with heterodinuclear (Mn-Fe) cofactors. Here, we first briefly review both the chemical principles underlying the O2-dependent oxidative chemistry of the 'classical' di-iron-carboxylate proteins and the two aforementioned strategies that have expanded their functional range, and then consider what metal ion(s) and what chemical mechanism(s) might be employed by the newly discovered cyanobacterial ADs.  相似文献   

15.
The chacma baboon (Papio ursinus) is extensively used in South Africa for biomedical research. Being a large primate, it is always necessary to apply some measure of chemical or physical restraint. The physiological effects of placing an animal in a restraint chair are compared with the effects of various chemical agents, such as ketamine, halothane, and ketamine/xylazine combination over 90 min. It was found that ketamine and thiopentone infusion were a satisfactory chemical restraint agent that gave a stable physiological state over 90 min.  相似文献   

16.
Vossen M  Hage JJ  Karim RB 《Plastic and reconstructive surgery》2000,105(3):1088-94; discussion 1095-6
Since the beginning of this century, trichloroacetic acid solutions of various concentrations have been used for chemical exfoliation. These solutions have been prepared by using four different formulas. To prepare a 50% solution, for instance, water may be added to 50 g of trichloroacetic acid crystals until 100 ml of solution is obtained (weight-to-volume solution). Alternatively, 50 g of water may be added to 50 g of trichloroacetic acid crystals (weight-to-weight solution), or 50 g of trichloroacetic acid crystals may be solved in 100 ml of water (weight-plus-volume solution). Finally, a saturated trichloroacetic acid solution (or "100% solution") may be diluted by an equal volume of water (dilution). Depending on the method used, these so-called 50% solutions contain 40 to 71 weight-to-volume percentages of trichloroacetic acid. From a review of 120 publications on trichloroacetic acid peeling that have appeared since 1926, it was concluded that the authors of 87 of these publications (73 percent) did not report their formula for the trichloroacetic acid solution. Any one of the four methods was reported to have been used by the 33 authors who did report their formula. Eight of 10 internationally reputed pharmacopeias were found not to include the formula of a trichloroacetic acid solution. Proper evaluation of results and prevention of complications of trichloroacetic acid chemexfoliation is only feasible if both the concentration and the formula of trichloroacetic acid solution are reported by the author. Practitioners who use a trichloroacetic acid solution need to establish that the concentration of the solution they apply corresponds with that of the solution reported in the literature.  相似文献   

17.
In Aesop's fable “The Crow and the Pitcher,” a thirsty crow uses stones to raise the level of water in a pitcher and quench its thirst. A number of corvids have been found to use tools in the wild [1], [2], [3] and [4], and New Caledonian crows appear to understand the functional properties of tools and solve complex physical problems via causal and analogical reasoning [5], [6], [7], [8], [9], [10] and [11]. The rook, another member of the corvid family that does not appear to use tools in the wild, also appears able to solve non-tool-related problems via similar reasoning [12]. Here, we present evidence that captive rooks are also able to solve a complex problem by using tools. We presented four captive rooks with a problem analogous to Aesop's fable: raising the level of water so that a floating worm moved into reach. All four subjects solved the problem with an appreciation of precisely how many stones were needed. Three subjects also rapidly learned to use large stones over small ones, and that sawdust cannot be manipulated in the same manner as water. This behavior demonstrates a flexible ability to use tools, a finding with implications for the evolution of tool use and cognition in animals.  相似文献   

18.
Soils are the skin of the earth. From both poles to the equator, wherever rocks or sediment are exposed at the surface, soils are forming through the physical and chemical action of climate and living organisms. The physical attributes (color, texture, thickness) and chemical makeup of soils vary considerably, depending on the composition of the parent material and other variables: temperature, rainfall and soil moisture, vegetation, soil fauna, and the length of time that soil–forming processes have been at work. United States soil scientists1 have classified modern soils into ten major groups and numerous subgroups, each reflecting the composition and architecture of the soils and, to some extent, the processes that led to their formation. The physical and chemical processes of soil formation have been active throughout geologic time; the organic processes have been active at least since the Ordovician.2 Consequently, nearly all sedimentary rocks that were deposited in nonmarine settings and exposed to the elements contain a record of ancient, buried soils or paleosols. A sequence of these rocks, such as most ancient fluvial (stream) deposits, provides a record of soil paleoenvironments through time. Paleosols are also repositories of the fossils of organisms (body fossils) and the traces of those organisms burrowing, food–seeking, and dwelling activities (ichnofossils). Indeed, most fossil primates are found in paleosols. Careful study of ancient soils gives new, valuable insights into the correct temporal reconstruction of the primate fossil record and the nature of primate paleoenvironments.  相似文献   

19.
Modern quantitative acid-base chemistry   总被引:8,自引:0,他引:8  
Quantitative analysis of ionic solutions in terms of physical and chemical principles has been effectively prohibited in the past by the overwhelming amount of calculation it required, but computers have suddenly eliminated that prohibition. The result is an approach to acid-base which revolutionizes our ability to understand, predict, and control what happens to hydrogen ions in living systems. This review outlines that approach and suggests some of its most useful implications. Quantitative understanding requires distinctions between independent variables (in body fluids: pCO2, net strong ion charge, and total weak acid, usually protein), and dependent variables [( HCO-3], [HA], [A-], [CO(2-)3], [OH-], and [H+] (or pH]. Dependent variables are determined by independent variables, and can be calculated from the defining equations for the specific system. Hydrogen ion movements between solutions can not affect hydrogen ion concentration; only changes in independent variables can. Many current models for ion movements through membranes will require modification on the basis of this quantitative analysis. Whole body acid-base balance can be understood quantitatively in terms of the three independent variables and their physiological regulation by the lungs, kidneys, gut, and liver. Quantitative analysis also shows that body fluids interact mainly by strong ion movements through the membranes separating them.  相似文献   

20.
The effects of physical and chemical restraint on glucose clearance and insulin secretion were evaluated during intravenous glucose tolerance testing in Macaca nigra. Conscious monkeys placed in plexiglas cylindrical restraining devices (CRD) appeared relaxed, but glucose clearance and insulin secretion were impaired. A combination of midazolam with ketamine, compared to ketamine alone, did not cause detectable changes in the intravenous glucose tolerance tests; midazolam also reduced adverse reactions to ketamine and extended the duration of anesthesia. The cylindrical restraining device can be convenient for examining monkeys, but it is limited by its adverse affects on metabolic and hormonal measurements in intravenous glucose-tolerance tests. Chemical restraint using ketamine with midazolam was more effective than ketamine alone.  相似文献   

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