| contribution of neocortex to sound localization in opossum (didelphis virginiana). | | 1972 | 5029954 |
| characteristics of common helminths of the virginia opossum (didelphis virginiana) from north carolina. | | 1972 | 4336985 |
| administration of test materials to the neonatal north american opossum (didelphys marsupialis virginiana kerr). | | 1971 | 4329243 |
| sedation and anesthesia of the virginia opossum, didelphis virginiana. | | 1971 | 4329235 |
| the habituation of auditory reflexes in the decorticate opossum (didelphis virginiana). | | 1971 | 5148514 |
| experimental study of pulmonary adenomas in the opossum (didelphis virginiana). | | 1971 | 4325695 |
| reticulospinal fibers of the opossum, didelphis virginiana. ii. course, caudal extent and distribution. | | 1971 | 4101680 |
| reticulospinal fibers of the opossum, didelphis virginiana. i. origin. | | 1971 | 4101679 |
| the pouch gas of the virgina opossum (didelphis virginiana). | | 1971 | 5552772 |
| a stereotaxic atlas of the opossum brain (didelphis virginiana). | | 1971 | 4950276 |
| a stereotaxic atlas of the opossum brain (didelphis virginiana). | | 1971 | 4940387 |
| the venous system of the head and neck of the opossum (didelphis virginiana). | | 1970 | 5522110 |
| late dna replication in the sex chromosomes of didelphis virginiana. | | 1970 | 5452039 |
| rna synthesis in the sex chromosomes of the opossum, didelphis virginiana. i. female. | | 1970 | 5452038 |
| rubrobulbar projections of the opossum (didelphis virginiana). | | 1970 | 5422531 |
| receptive fields of single cells of a marsupial visual cortex of didelphis virginiana. | | 1970 | 5412291 |
| the rubro-spinal tract of the opposum (didelphis virginiana). | | 1970 | 5412717 |
| hypertension in the opossum didelphis virginiana. | | 1970 | 5409896 |
| a further study of adrenal function in the opossum (didelphis virginiana). | | 1969 | 5403614 |
| preliminary estimates of the mean duration of the s-phase in the opossum, didelphis virginiana. | | 1969 | 5347641 |
| the opossum, didelphis virginiana, as a laboratory animal. | | 1969 | 4240729 |
| a review of the anatomy and neurophysiology of the opossum (didelphis virginiana) visual system. | | 1969 | 4894785 |
| blood chemical and hematological studies in the laboratory-confined, unanesthetized opossum, didelphis virginiana. | | 1969 | 4240125 |
| efferent tectal pathways of the opossum (didelphis virginiana). | | 1969 | 5780528 |
| the distribution and control of osmosensitive cells within the hypothalamus of the opossum (didelphis virginiana). | | 1969 | 4889623 |
| the pattern of neocortical projections to the mesencephalon of the opossum, didelphis virginiana. | | 1968 | 5712010 |
| hemograms of laboratory-confined opossums (didelphis virginiana). | | 1968 | 5680429 |
| the basilar pontine gray of the opossum (didelphis virginiana). ii. experimental determination of neocortical input. | | 1968 | 5733930 |
| the basilar pontine gray of the opossum (didelphis virginiana). i. morphology. | | 1968 | 4185130 |
| bacterial endocarditis, glomerulonephritis and amyloidosis in the opossum (didelphis virginiana). | | 1968 | 5690168 |
| visual receptive fields from cells of a marsupial (didelphis virginiana) superior colliculus. | | 1968 | 4881348 |
| studies of a primitive mammalian spleen, the opossum (didelphis virginiana). | | 1968 | 5666529 |
| the striatum of the opossum, didelphis virginiana. description and experimental studies. | | 1967 | 5582292 |
| steroid production by the normal opossum (didelphis virginiana) adrenal in vitro. | | 1967 | 6055283 |
| the dentition of a 25-day pouch-young specimen of didelphis virginiana (didelphidae: marsupialia). | | 1967 | 5233942 |
| hypothalamic mechanisms for sexual, aggressive, and other motivational behaviors in the opossium, didelphis virginiana. | | 1967 | 6070717 |
| dna replication patterns and chromosomal protein synthesis in opossum lymphocytes in vitro. | dna replication patterns were determined in the autosomes and sex chromosomes of phytohemagglutinin-stimulated lymphocytes from the opossum (didelphis virginiana) by employing thymidine-(3)h labeling and high-resolution radioautography. opossum chromosomes are desirable experimental material due to their large size, low number (2n = 22), and morphologically distinct sex chromosomes. the autosomes in both sexes began dna synthesis synchronously and terminated replication asynchronously. one femal ... | 1967 | 6036519 |
| interneocortical connections in the opossum, didelphis virginiana. | | 1967 | 6035000 |
| afferent connections to neocortex in the opossum (didelphis virginiana). | | 1967 | 6034492 |
| fine structure of the prostatic epithelium of the opossum (didelphis virginiana kerr). | | 1965 | 4287015 |
| eeg correlates of tonic immobility in the opossum (didelphis virginiana). | | 1965 | 14297543 |
| [the wall construction and vascular system of the uterus of the opossum (didelphis virginiana)]. | | 1965 | 14291393 |
| short-term caloric regulation in the adult opossum (didelphis virginiana). | | 1965 | 14254568 |
| [the morphology of the blood-brain barrier in the brain of the opossum (didelphis virginiana)]. | | 1965 | 5836802 |
| nerve endings of the north american opossum (didelphis virginiana): a comparison with nerve endings of primates. | | 1964 | 14289936 |
| fine structure of the neurohypophysis of the opossum (didelphis virginiana). | the neurohypophysis of the opossum (didelphis virginiana) was studied by electron microscopy in order to amplify bodian's classic light microscopic observations in which he demonstrated a definite lobular pattern. the lobule of the opossum neurohypophysis is divided into three regions: a hilar, a palisade, and a septal zone. the hilar portion contains bundles of nerve fibers, the extensions of the hypothalamo-hypophyseal tract containing neurofilaments but few neurosecretory granules. in the opo ... | 1964 | 14128048 |
| motor representation in the cerebral cortex of the opossum (didelphis virginiana). | | 1963 | 14100023 |
| sensory representation in the cerebral cortex of the opossum (didelphis virginiana). | | 1963 | 14100022 |
| the chromosomes of the opossum, didelphis virginiana. | | 1962 | 13911443 |
| cholesterol in the tapetum lucidum of the eye of of the opossum, didelphis virginiana. | | 1961 | 13735996 |
| pharmacological characteristics of neurohypophysial hormones from a marsupial (didelphis virginiana) and a monotreme (tachyglossus (echnidna) aculeatus). | | 1960 | 14442120 |
| the basis of nuclear sex difference in somatic cells of the opossum didelphis virginiana. | | 1960 | 14428478 |
| the effect of high oxygen concentrations on the opossum pouch young (didelphis virginiana). | | 1960 | 14430554 |
| experimental reversal of sex in the gon ads of the opossum didelphis virginiana. | | 1955 | 16589726 |
| a new experimental animal for psychiatric research: the opossum, didelphis virginiana. | | 1954 | 13156599 |
| cytological study of rhopalias macracanthus chandler, 1932, a trematode from the opossum, didelphis virginiana. | | 1949 | 18133322 |
| the early postnatal development of the brain of the opossum, didelphis virginiana. | | 1948 | 18858154 |
| the opossum, didelphis virginiana kerr, a new host for paragonimus in tennessee. | | 1941 | 17800620 |
| eosinophilic meningoencephalitis associated with rat lungworm (angiostrongylus cantonensis) migration in two nine-banded armadillos (dasypus novemcinctus) and an opossum (didelphis virginiana) in the southeastern united states. | angiostrongylus cantonensis, the rat lungworm, was the cause of neural larval migrans in two nine-banded armadillos (dasypus novemcinctus) and one virginia opossum (didelphis virginiana) from the southeastern united states. histologic findings in all three cases included eosinophilic meningoencephalitis with variable numbers of nematode larvae in the meninges or the neuroparenchyma. in two of the three cases, nematodes were extracted from brain tissue via a "squash prep" method. identification o ... | 2017 | 28626635 |
| quantifying dilution and amplification in a community of hosts for tick-borne pathogens. | recent controversy over whether biodiversity reduces disease risk (dilution effect) has focused on the ecology of lyme disease, a tick-borne zoonosis. a criticism of the dilution effect is that increasing host species richness might amplify disease risk, assuming that total host abundance, and therefore feeding opportunities for ticks, increase with species richness. in contrast, a dilution effect is expected when poor quality hosts for ticks and pathogens (dilution hosts) divert tick blood meal ... | 2016 | 27209790 |
| pulmonary lesions caused by the lungworm (didelphostrongylus hayesi) in the opossum (didelphis virginiana) in colima, mexico. | didelphostrongylus hayesi is an important and prevalent pulmonary nematode in the opossum ( didelphis virginiana ). an in-depth description of the pulmonary lesions caused by this nematode is lacking. the objective of this investigation was to make a detailed account of the gross, subgross, and microscopic changes that occur in the lungs of opossums naturally infected with d. hayesi. forty-four opossums trapped in the state of colima, mexico, were euthanized by an overdose of barbiturates. follo ... | 2017 | 28749264 |
| sarcocystis neurona and neospora caninum in brazilian opossums (didelphis spp.): molecular investigation and in vitro isolation of sarcocystis spp. | sarcocystis neurona and neospora spp. are protozoan parasites that induce neurological diseases in horses and other animal species. opossums (didelphis albiventris and didelphis virginiana) are definitive hosts of s. neurona, which is the major cause of equine protozoal myeloencephalitis (epm). neospora caninum causes abortion in cattle and infects a wide range of animal species, while n. hughesi is known to induce neurologic disease in equids. the aims of this study were to investigate s. neuro ... | 2017 | 28807293 |
| seed dispersal of diospyros virginiana in the past and the present: evidence for a generalist evolutionary strategy. | several north american trees are hypothesized to have lost their co-evolved seed disperser during the late-pleistocene extinction and are therefore considered anachronistic. we tested this hypothesis for the american persimmon (diospyros virginiana) by studying the effects of gut passage of proposed seed dispersers on seedling survival and growth, natural fruiting characteristics, and modern animal consumption patterns. we tested gut passage effects on persimmon seeds using three native living s ... | 2017 | 28616198 |
| camera trap arrays improve detection probability of wildlife: investigating study design considerations using an empirical dataset. | camera trapping is a standard tool in ecological research and wildlife conservation. study designs, particularly for small-bodied or cryptic wildlife species often attempt to boost low detection probabilities by using non-random camera placement or baited cameras, which may bias data, or incorrectly estimate detection and occupancy. we investigated the ability of non-baited, multi-camera arrays to increase detection probabilities of wildlife. study design components were evaluated for their infl ... | 2017 | 28422973 |
| abiotic and biotic contributors to support inter-epidemic francisella tularensis in an agricultural peri-urban environment. | to characterize the inter-epidemic ecology of francisella tularensis, we surveyed vertebrates and invertebrates for the abundance, spatial distribution, and status of infection at a site in northern california that had evidence of endemic type b tularemia. we collected 2910 mosquitoes, 77 biting flies, 704 ticks, 115 mammals, and 1911 aquatic invertebrates in 2013-2014. real-time pcr on all mosquitoes, 40 biting flies, 113 aquatic invertebrates, and 650 ticks did not detect f. tularensis dna. in ... | 2017 | 28968195 |
| trypanosoma cruzi strain tciv infects raccoons from illinois. | the northern limits of trypanosoma cruzi across the territory of the united states remain unknown. the known vectors triatoma sanguisuga and t. lecticularia find their northernmost limits in illinois; yet, earlier screenings of those insects did not reveal the presence of the pathogen, which has not been reported in vectors or reservoir hosts in this state. | 2018 | 29211106 |
| laminar and non-laminar patterns of acetylcholinesterase activity in the marsupial lateral geniculate nucleus. | acetylcholinesterase (ache) distribution in the dorsal lateral geniculate nucleus (lgd) of 3 polyprotodont and 3 diprotodont marsupials has been compared with the cytoarchitecture and, as appropriate, with retinal terminal bands (rtbs) as demonstrated by tracers injected into the vitreous body. in this series those polyprotodont marsupials showing only partial segregation of retinal input (virginia opossum and tasmanian devil), display the least cell laminar differentiation. in them ache stainin ... | 1989 | 2731033 |
| myosin isoform expression in the prehensile tails of didelphid marsupials: functional differences between arboreal and terrestrial opossums. | prehensile tails are defined as having the ability to grasp objects and are commonly used as a fifth appendage during arboreal locomotion. despite the independent evolution of tail prehensility in numerous mammalian genera, data relating muscle structure, physiology, and function of prehensile tails are largely incomplete. didelphid marsupials make an excellent model to relate myosin heavy chain (mhc) isoform fiber type with structure/function of caudal muscles, as all opossums have a prehensile ... | 2014 | 24832677 |
| prevalence of trypanosoma cruzi and organ alterations in virginia opossums (didelphis virginiana) from western mexico - short communication. | small populations of virginia opossum (didelphis virginiana) in western mexico are endangered by hunting and natural predators as well as by different kinds of diseases. after two serological analyses using serodia® latex particle agglutination and indirect haemagglutination (iha) tests, 35 (53.03%) of 66 collected opossums in two small towns in western mexico were positive for the presence of trypanosoma cruzi. twenty-eight of the 35 seropositive opossums had pathological lesions: 11 had change ... | 2017 | 29256285 |
| toward an ecological framework for assessing reservoirs of vector-borne pathogens: wildlife reservoirs of trypanosoma cruzi across the southern united states. | wildlife species are critical for both feeding vectors and serving as reservoirs of zoonotic vector-borne pathogens. transmission pathways leading to disease in humans or other target taxa might be better understood and managed given a complete understanding of the relative importance of different reservoir species in nature. using the conceptual framework of "reservoir potential," which considers elements of both reservoir competence and vector-host contact, we review the wildlife reservoirs of ... | 2017 | 29106561 |
| histopathological changes in the liver and stomach of didelphis virginiana (didelphimorphia: didelphidae) during natural infection with gnathostoma turgidum (nematoda: gnathostomidae). | gnathostoma turgidum is a nematode parasite that exploits the stomach of virginian opossums, didelphis virginiana, in latin america. the opossum is the definitive host of g. turgidum in the wild. intrahepatic growth and maturation of the parasite, subsequent migration to the stomach and spontaneous expulsion are common. however, the histopathological lesions caused by g. turgidum are poorly described. a better understanding of the life cycle of this parasite and the pathological changes in natur ... | 2017 | 29103381 |
| the transcriptome of thedidelphis virginianaopossum kidney ok proximal tubule cell line. | the ok cell line derived from the kidney of a female opossumdidelphis virginianahas proven to be a useful model in which to investigate the unique regulation of ion transport and membrane trafficking mechanisms in the proximal tubule (pt). sequence data and comparison of the transcriptome of this cell line to eutherian mammal pts would further broaden the utility of this culture model. however, the genomic sequence ford. virginianais not available and although a draft genome sequence for the opo ... | 2017 | 28615248 |
| reproductive disorders of marsupials. | marsupial reproduction differs significantly in anatomy and physiology from that of placental mammals. the gastrointestinal and urogenital tracts empty into a cloaca. reproductive parameters include gestation and pouch time, as the fetus develops outside of the uterus. captive marsupials discussed include sugar gliders), short-tailed opossums, virginia opossums, and tammar and bennett's wallabies. common disease conditions include joey eviction, pouch infections, mastitis, metritis, prostatitis, ... | 2017 | 28169182 |
| gastric ischemic conditioning increases neovascularization and reduces inflammation and fibrosis during gastroesophageal anastomotic healing. | the incidence of anastomotic leak and stricture after esophagectomy remains high. gastric devascularization followed by delayed esophageal resection has been proposed to minimize these complications. we investigated the effect of ischemic conditioning duration on anastomotic wound healing in an animal model of esophagogastrectomy. | 2013 | 23247735 |
| a genetic analysis of the virginia opossum mating system: evidence of multiple paternity in a highly fragmented landscape. | using molecular techniques, we examined patterns of paternity in virginia opossums occupying a highly fragmented agricultural landscape in northern indiana. during 2008, we collected tissue from 64 females and their pouch young in 34 forest patches distributed over a 1100-km(2) region. using genotypes from 10 microsatellite loci, we determined the minimum number of fathers contributing to each litter using gerud 1.0. genotyped offspring with known mothers were then analyzed using cervus 3.0, inc ... | 2010 | 19995804 |
| methylation analysis of a marsupial x-linked cpg island by bisulfite genomic sequencing. | paternal x chromosome inactivation occurs in rodent extraembryonic membranes and in all tissues of marsupials. methylation of cpg islands occurs on the inactive x in eutherians and is considered to be a stabilizing mechanism. the only previous study of a marsupial x-linked cpg island was of the g6pd gene of the virginia opossum, in which the paternally derived allele is not completely repressed. we have cloned the 5' end of the g6pd gene from an australian marsupial, the common wallaroo, and seq ... | 1996 | 8919690 |
| perivitelline space of marsupial oocytes: extracellular matrix of the unfertilized oocyte and formation of a cortical granule envelope following the cortical reaction. | the purpose of this study was to characterize the structure of the vestments surrounding unfertilized and cortical granule-reacted oocytes from a marsupial, the grey short-tailed opossum monodelphis domestica and to determine if a cortical granule envelope (cge) forms in the perivitelline space (pvs) following the cortical reaction. unfertilized oocytes collected from mature ovarian follicles and oviducal oocytes that had undergone a cortical reaction were fixed for electron microscopy in the pr ... | 1995 | 8588937 |
| locomotory energetics and metabolic fuel reserves of the virginia opossum. | marsupials have lower resting metabolic rates than placental mammals, but it is not clear whether particular species can extend this energetic advantage to locomotion. some active marsupials have a low cost of locomotion, but other more sedentary species, such as the virginia opossum, appear to run very inefficiently. steady-state rates of o2 consumption (vo2) and co2 production (vco2) were measured at rest and during horizontal treadmill exercise in wild-caught, trained opossums. average daily ... | 1994 | 7852899 |
| development of early cell lineages in marsupial embryos: an overview. | all major embryonic and extra-embryonic cell lineages are established before implantation in marsupials. in reptiles, birds, monotremes and most marsupials, the zygote is polarized, sometimes markedly so, and the cleavage pattern in relation to the polarized state provides the mechanism for the generation of positional signals. these ensure that the embryonic cell lineages develop in the centre of the developing blastoderm or blastocyst epithelium and the extra-embryonic lineages at the peripher ... | 1994 | 7878224 |
| odors as cues for orientation to mothers by weanling virginia opossums. | three experiments were conducted to investigate whether wholebody and pouch odors facilitate social cohesion between young virginia opossums and their mothers just prior to weaning. in experiment 1, young oriented toward plastic buckets containing their mothers, directing significantly higher levels of investigative behavior and more distress vocalizations toward them than toward buckets containing unrelated lactating females. in experiment 2, young oriented toward and investigated empty buckets ... | 1992 | 24254869 |
| anatomy of the bilioduodenal junction of the opossum. | prevention of reflux is a major function of the terminal biliary duct system at its junction with the duodenum. we examined this area via scanning electron microscopy and light microscopy to explore anatomic features that might play such a role in the virginia opossum, a species with a highly developed sphincter of oddi (so). the terminal apparatus, most of which consists of a dilated extramural ampulla, has a lumen with abundant folds. mucus is produced by the lining epithelium and by a plethor ... | 1992 | 1554107 |
| estradiol and progesterone profiles indicate a lack of endocrine recognition of pregnancy in the opossum. | concentrations of estradiol and progesterone in blood collected during the 12.5-day gestation period of the virginia opossum were not significantly different from those during equivalent days of the estrous cycle. progesterone was correlated with an index of corpora luteral mass. ratio of estradiol to progesterone were highest 3 to 4 days before estrus and on the day of parturition. | 1981 | 7233228 |
| the laminar distribution and ultrastructure of fibers projecting from three thalamic nuclei to the somatic sensory-motor cortex of the opossum. | the projections of the ventrobasal complex (vb), the ventrolateral complex (vl), and the central intralaminar nucleus (cin) to the somatic sensory-motor (ssm) cortex of the virginia opossum were studied with light and electron microscopic autoradiographic methods. vb, vl, and cin have overlapping projections to ssm cortex and each one also projects to an additional cortical area. unit responses to somatic sensory stimulation and the areal and laminar distribution of axons in cortex is different ... | 1981 | 7240451 |
| the ontogenesis of sleep states, thermogenesis, and thermoregulation in the virginia opossum. | polygraphic recordings of sleep and wakefulness were obtained over 4-hr periods from infant opossums, aged 48-79 days, while they were in the mothers' pouches. concurrent body temperature measurements were obtained from littermates held at ambient temperatures of 25 and 30 degrees c. the ontogenesis of sleep was similar to that of placental mammals: quiet sleep increased from 13% sleep time at 48 days to 55% at 79 days; conversely, active sleep decreased from 87% to 45%, respectively. the amplit ... | 1980 | 7409325 |
| age ratios, weights, and reproduction of the virginia opossum in north louisiana. | | 1978 | 750645 |
| the second somatic sensory area (smii) of opossum neocortex. | organization of the neocortical second somatic sensory area (smii) of anesthetized virginia opossums has been examined utilizing micro-electrode recording techniques. smii is situated between the first somatic sensory area (smi) medially, and the rhinal fissure laterally. the head representation is located anteromedially within smii, and the hindlimb representation posterolaterally, with the forelimb representation in between. approximately 49% of smii is devoted to representation of the head, 3 ... | 1977 | 864034 |
| thalmocortical projections from the mediodorsal nucleus in the virginia opossum. | | 1973 | 4121726 |
| distribution of cerebellar and somatic lemniscal projections in the ventral nuclear complex of the virginia opossum. | | 1973 | 4709264 |
| convergent projection of three separate thalamic nuclei on to a single cortical area. | three distinct sensory-motor nuclei in the thalamus project to parietal cortex in the virginia opossum; the ventral posterior nucleus receives inputs from somatic sensory structures and projects to layers iv and iii, the ventral anterolateral nucleus receives inputs from motor structures and projects to layers iv and iii and inner i, and the central intralaminar nucleus receives inputs from sensory, motor, and other structures and projects to layers vi through outer i. the physiologically define ... | 1973 | 4683125 |
| development of pulmonary reflexes and pattern of breathing in virginia opossum. | | 1972 | 5063396 |
| development of the chemical control of breathing in the virginia opossum. | | 1972 | 5024173 |
| experimental talipes in the virginia opossum. | | 2005 | 5133035 |
| the contribution of the dorsal lateral geniculate nucleus to the total pattern of thalamic terminations in striate cortex of the virginia opossum. | | 1971 | 5148973 |
| the areas and layers of corticocortical terminations in the visual cortex of the virginia opossum. | | 1971 | 5541350 |
| retrograde degeneration study of somatic sensory thalamocortical connections in brain of virginia opossum. | | 1968 | 5638868 |
| colour vision in the virginia opossum. | | 1967 | 6031824 |
| the virginia opossum in psychological research. | | 1966 | 5981079 |
| spontaneous alternation in the virginia opossum. | | 1966 | 5912827 |
| somatic sensory representation in the thalamic ventrobasal complex of the virginia opossum. | | 1966 | 5961965 |
| position reversal training in the virginia opossum: evidence for the acquisition of a learning set. | | 1965 | 5825697 |