Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| coevolution between crossbills and black pine: the importance of competitors, forest area and resource stability. | studies of predator-prey interactions have found that geographically structured coevolution has played an important role in the adaptive diversification of crossbills (loxia spp.). we extend those studies by considering common crossbills (l. curvirostra) in the mediterranean where they rely on seeds in the cones of black pine (pinus nigra). on the continent, where tree squirrels (sciurus vulgaris) are present, enhanced defenses against crossbills were most evident in larger areas of pine forest. ... | 2009 | 19228273 |
| poxviral disease in red squirrels sciurus vulgaris in the uk: spatial and temporal trends of an emerging threat. | the squirrel poxvirus (sqpv) is the probable mediator of apparent competition between the introduced invading gray squirrel (sciurus carolinensis) and the red squirrel (sciurus vulgaris) in the uk, and modeling studies have shown that this viral disease has had a significant impact on the decline of the red squirrel in the uk. however, given our limited understanding of the epidemiology of the disease, and more generally the effects of invasive species on parasite ecology, there is a need to inv ... | 2008 | 18923872 |
| natural infection with two genotypes of cryptosporidium in red squirrels (sciurus vulgaris) in italy. | we investigated the genotypes of cryptosporidium infecting red squirrels (sciurus vulgaris l.) in two areas of the western alps in italy. examination of 141 faecal samples from 70 red squirrels revealed oocysts of cryptosporidium in 17 animals (24.3%). based on 18s rrna gene sequencing, two genotypes of cryptosporidium species were found: 15 squirrels were positive for the cryptosporidium ferret genotype and 2 for the cryptosporidium chipmunk genotype i. the occurrence and intensity of cryptospo ... | 2008 | 18666411 |
| [effects of different forest management alternatives on sciurus vulgaris habitat]. | a spatially explicit landscape model landis was applied to simulate the forest landscape changes under four management alternatives (no cutting, clear cutting, selective cutting i and ii) in youhao forestry bureau located in small xing' an mountain from 2000 to 2200. the outcomes from landis were combined with a landscape-level habitat suitability index (hsi) model in a gis environment to assess sciurus vulgaris habitat quality. the results showed that the increase of suitable habitat area and t ... | 2008 | 18655576 |
| epidemics of squirrelpox virus disease in red squirrels ( sciurus vulgaris): temporal and serological findings. | squirrelpox virus (sqpv) causes a fatal disease in free-living red squirrels (sciurus vulgaris) which has contributed to their decline in the united kingdom. given the difficulty of carrying out and funding experimental investigations on free-living wild mammals, data collected from closely monitored natural outbreaks of disease is crucial to our understanding of disease epidemiology. a conservation programme was initiated in the 1990s to bolster the population of red squirrels in the coniferous ... | 2009 | 18606024 |
| [fleas community in introduced siberian chipmunks (tamias sibiricus laxmann) in forest of sénart, france]. | we examined the fleas community in an introduced population of siberian chipmunks, tamias sibiricus, between 2005 and 2007, in the forest of sénart (essonne, france). we collected and identified 383 fleas on 463 chipmunks (total: 1,891 captures on 471 chipmunks). in 2005, 120 fleas were also collected on 65 bank voles, clethrionomys glareolus, and on 25 wood mice, apodemus sylvaticus, trapped within the same area. ceratophyllus sciurorum sciurorum formed 73.6% of the chipmunks' flea community, w ... | 2008 | 18416245 |
| detection of new babesia microti-like parasites in a rhesus monkey (macaca mulatta) with a suppressed plasmodium cynomolgi infection. | a new type of piroplasm, phylogenetically closest to babesia microti-like parasites previously detected in eurasian red squirrels (sciurus vulgaris orientis), was identified in a rhesus monkey (macaca mulatta) imported from china. after challenge with plasmodium cynomolgi m strain blood-stage parasites, the rhesus monkey repeatedly showed markedly reduced levels of plasmodium parasitemia when compared with animals not infected with this organism. | 2008 | 18385363 |
| campylobacter jejuni in the red squirrel (sciurus vulgaris) population of southern italy. | rectal swab samples were collected from 60 red squirrels (sciurus vulgaris) from july 2006 to april 2007 in southern italy. samples were tested for campylobacter jejuni and c. coli by culture methods and suspected colonies were then confirmed by polymerase chain reaction. c. jejuni was detected in 5/60 (8.3%) samples examined but infection status was not related to age or sex and c. coli was not isolated. this is believed to be the first report of c. jejuni infection in the red squirrel. | 2009 | 17980635 |
| enteric adenovirus infection in a red squirrel (sciurus vulgaris). | 2007 | 17369486 | |
| hepatozoon species infection in wild red squirrels (sciurus vulgaris) on the isle of wight. | postmortem examinations of 49 red squirrels (sciurus vulgaris) found dead on the isle of wight revealed the presence of a hepatozoon species in 18 of them (37 per cent). the prevalence of infection was highest in subadult animals and no juveniles were infected. the prevalence was higher in the squirrels dying from natural causes (nine of 12) than in squirrels killed in road accidents (seven of 27). the weight of infection varied, and there were heavy infections in squirrels dying from toxoplasmo ... | 2006 | 16905733 |
| babesia microti-like parasites detected in eurasian red squirrels (sciurus vulgaris orientis) in hokkaido, japan. | six eurasian red squirrels (sciurus vulgaris orientis), victims of road traffic found during 2002 and 2004 near the noppro forest park in ebetsu, hokkaido, japan, were examined for the presence of babesia parasites. three of the six squirrels exhibited positive signals by nested pcrs targeting both the 18s rrna and beta-tubulin genes. three squirrels proved to be infected with a b. microti-like parasite as evidenced by sequencing the amplified dnas and by the morphology of the intraerythrocytic ... | 2006 | 16891774 |
| genomic characterization of a novel poxvirus contributing to the decline of the red squirrel (sciurus vulgaris) in the uk. | the genome of a virulent squirrelpox virus (sqpv) isolate was characterized in order to determine its relationship with other poxviruses. restriction enzyme analysis suggested a genome length of approximately 158 kb, whilst sequence analysis of the two ends of the genome indicated a g + c composition of approximately 66 %. two contiguous stretches of 23 and 37 kb at the left-hand and right-hand ends of the genome, respectively, were sequenced allowing the identification of at least 59 genes cont ... | 2006 | 16847106 |
| morphocytochemical analysis of neuron populations in the ganglion layer of the cerebellar cortex of birds and mammals living in similar habitats. | the neuron populations in the ganglion layer of the cerebellar cortex of birds and mammals living in similar habitats, i.e., the common squirrel and the house sparrow (sciurus vulgaris and passer domesticus), living in an air/land habitat, and the swamp beaver (nutria) and domestic goose (myocastor coypus and anser domesticus), living in an earth-water habitat, were studied. morphocytochemical measures were assessed, i.e., the density of purkinje cells per unit gyrus length and their sizes, stai ... | 2005 | 16270169 |
| [morphological and cytochemical analysis of neuronal populations in the ganglion cell layer of the cerebellar cortex in birds and mammals living in similar habitats]. | neuron populations of ganglion cell layer of cerebellar cortex were studied in birds and mammals, which were living in similar habitats: air-land habitat (squirrel--sciurus vulgaris and sparrow--passer domesticus) and land-water habitat (nutria--myocastor coypus and goose--anser domesticus). the following morpho-cytochemical indices were analyzed: density of purkinje cell distribution per unit gyms length, area parameters, tinctorial properties, protein content of neuron populations of ganglion ... | 2004 | 15839246 |
| the geographic selection mosaic for squirrels, crossbills and aleppo pine. | the interactions between many species are structured in a geographic mosaic of populations among which selection is divergent. here we tested the hypothesis that such a geographic selection mosaic arises for common crossbills (loxia curvirostra) feeding on seeds in the cones of aleppo pine (pinus halepensis) because of geographic variation in the occurrence of european red squirrels (sciurus vulgaris). on the iberian peninsula, sciurus exerted directional selection favouring larger cones with la ... | 2005 | 15715841 |
| geographical distance and physical barriers shape the genetic structure of eurasian red squirrels (sciurus vulgaris) in the italian alps. | red squirrels (sciurus vulgaris) are widely distributed throughout eurasia, occurring in many types of coniferous and mixed-deciduous forests. in fragmented landscapes, small and partly isolated populations with low immigration rates show reduced genetic diversity, but reforestation can increase gene flow and restore levels of genetic variation in a few decades. no studies have so far investigated the genetic structure of red squirrel in large, continuous forests. the italian alps are presently ... | 2005 | 15660938 |
| epidemiology of leishmaniasis in ecuador: current status of knowledge -- a review. | although leishmaniasis is regarded as a significant health problem in ecuador by the ministry of health, and the incidence has increased over the last years, an official map on the geographic distribution of disease and sand fly vectors or a control strategy do not exist yet. this article reviews the current situation based on published information to improve our knowledge and understand the epidemiological situation of leishmaniasis in ecuador in order to help future research and to develop a n ... | 2004 | 15654419 |
| bone assessment of free-living red squirrels (sciurus vulgaris) from the united kingdom. | metabolic bone disease has been reported in free-living red squirrels (sciurus vulgaris) in the united kingdom but the prevalence of this disease is unknown. in this study the bone quality of free-living red squirrels in the uk was assessed by radiology and bone densitometry. the study comprised 20 red squirrels found dead and submitted to the zoological society of london (uk) between 1997 and 1998, 10 were from the isle of wight (iow), where gray squirrels (sciurus carolinensis) are absent, and ... | 2004 | 15465719 |
| oral disease in free-living red squirrels (sciurus vulgaris) in the united kingdom. | ninety-one red squirrels (sciurus vulgaris) found dead in the uk between january 1994 and august 1998 were necropsied at the institute of zoology (london, uk); their oral cavities were examined visually, and in eight cases, radiographically. four red squirrels, which had evidence of oral disease when necropsied as part of a mortality survey, also were examined. a low prevalence (prevalence = 0.033, se = 0.02, n = 91) of oral disease was found in free-living red squirrels. in only two cases was o ... | 2004 | 15362817 |
| a novel poxvirus lethal to red squirrels (sciurus vulgaris). | a parapoxvirus has been implicated in the decline of the red squirrel in the united kingdom. virus was isolated from an outbreak of lethal disease in red squirrels in the north-east of england. experimental infection of captive-bred red squirrels confirmed that this virus was the cause of the severe skin lesions observed. electron microscopic examination of the virus showed that it had a morphology typical of parapoxviruses whilst preliminary sequence data suggested a genomic g+c composition of ... | 2003 | 14645914 |
| [morphologic aspects of the diencephalo-hypophysial neurosecretory apparatus of the mole (talpa europea) and squirrel (sciurus vulgaris)]. | 1954 | 14351559 | |
| zumptiella coreaensis, a new species of nasal mite from the korean squirrel, sciurus vulgaris coreae sowerby, 1921. | 1964 | 14204116 | |
| [comparative studies on the adaptive behavior of the pure cone retina. citellus citellus, sciurus vulgaris]. | 1962 | 14028319 | |
| [seasonal weight variations of the adrenal glands of the squirrel (sciurus vulgaris) in the department du tarn]. | 1962 | 14026806 | |
| [topographic and volumetric study of the pituitary of the squirrel (sciurus vulgaris)]. | 1962 | 14026805 | |
| [sensitivity of sciurus vulgaris to visceral leishmaniasis]. | 2013 | 13329771 | |
| prevalence of coccidia parasites (protozoa) in red squirrels (sciurus vulgaris): effects of host phenotype and environmental factors. | we investigated the relative importance of environmental factors versus host phenotype in determining parasite prevalence in eurasian red squirrels (sciurus vulgaris). one hundred and forty-three fecal samples of 116 different squirrels collected in 2000 and 2001 from five study areas in the italian alps, were examined for intestinal protozoans. two species of eimeria were present with a medium to high prevalence in both years and in all areas, while two other species were rare, occurring only i ... | 2003 | 12898385 |
| new world origins for haemoparasites infecting united kingdom grey squirrels (sciurus carolinensis), as revealed by phylogenetic analysis of bartonella infecting squirrel populations in england and the united states. | phylogenetic analyses of bartonella have suggested divergence between bartonellae that infect mammals native to the old and new worlds. we characterized bartonella isolated from eastern grey squirrels (sciurius carolinensis) in the united states and from grey and red squirrels (sciurus vulgaris) in the united kingdom by nucleotide sequence comparison (glta and groel). isolates from grey squirrels in the united states and the united kingdom were identical, and most similar to bartonella vinsonii, ... | 2002 | 12558350 |
| helminth fauna of the red squirrel (sciurus vulgaris linnaeus, 1758) in belorussian polesie. | 2002 | 12375168 | |
| malignant melanoma of the eyelid in a red squirrel (sciurus vulgaris orientis). | a 6-year-old male red squirrel (sciurus vulgaris orientis) developed bilateral tumors of upper and lower eyelids. the tumors in the left lid recurred despite surgical removal. necropsy revealed metastasis to the lung. the neoplastic cells were epithelioid and highly pleomorphic, and only a few cells contained melanin granules. occasionally melanoma cells were immunoreactive for s100, neuron-specific enolase and vimentin, and a small number of cells for cytokeratin. ultrastructurally, the presenc ... | 2002 | 11999447 |
| trace metal concentrations in squirrel (sciurus vulgaris) and black rat (rattus muridae) inhabiting roadside ecosystem. | 2001 | 11353372 | |
| microsatellite loci in the eurasian red squirrel, sciurus vulgaris l. | 2000 | 11123634 | |
| where do rodents fit? evidence from the complete mitochondrial genome of sciurus vulgaris. | 2000 | 10833205 | |
| genetic structure of fragmented populations of red squirrel (sciurus vulgaris) in the uk. | the relationships among 207 squirrels from 12 locations in the uk and three in mainland europe were examined using mitochondrial dna (mtdna) control region sequence. twenty-six haplotypes were detected, many of which were population specific. eighty per cent of the populations analysed contained two or more haplotypes. hierarchical analysis of molecular variance showed the majority of genetic variation to be partitioned among populations. genetic diversity varied considerably within the uk, and ... | 1999 | 10703551 |
| [functional characteristics of the binocular sector neurones of the squirrel sciurus vulgaris striate cortex]. | 2006 | 10198997 | |
| [paranoplocephala longivaginata sp. n. (cyclophyllidea: anoplocephalidae)--a new cestode from rodents of the western siberia]. | a new species of anoplocephalidean cestode paranoplocephala longivaginata sp. n. from some rodents (clethrionomys rutilus, sciurus vulgaris) of the western siberia is described. the new species differs from formerly known species of the genus paranoplocephala by a structure of copulatory organs: the length of cirrus and the length of vagina exceed the length of genital bursa more than 1.5 times; the internal surface of the vagina is covered with hair-like bristles along all its length. | 1998 | 9813885 |
| relationship between borrelia burgdorferi sensu lato species, red squirrels (sciurus vulgaris) and ixodes ricinus in enzootic areas in switzerland. | the infection and reservoir status of red squirrels (sciurus vulgaris) for borrelia burgdorferi sensu lato were studied in switzerland. b. burgdorferi sensu lato was isolated from 15 skin samples from 4/6 dead red squirrels, victims of road traffic. isolates were identified using restriction fragment length polymorphism (rflp): b. burgdorferi sensu stricto was present in 14 culture tubes containing skin samples and b. afzelii in two other tubes. a mixed infection was revealed in one case. a tota ... | 1998 | 9638274 |
| effects of temporal and spatial variation in habitat quality on red squirrel dispersal behaviour | immigration patterns and the frequency of breeding dispersal in tree squirrels are predicted to be related to the amount of temporal and spatial variation in tree seed crops, their primary food supply. we studied eurasian red squirrel, sciurus vulgarisdispersal patterns in a stable habitat with predictable food supply and a variable habitat with large temporal and spatial variations in food availability. in both habitats, we observed a male-biased immigration in spring and a female-biased immigr ... | 1997 | 9268475 |
| phylogenetic relationships among japanese species of the family sciuridae (mammalia, rodentia), inferred from nucleotide sequences of mitochondrial 12s ribosomal rna genes. | in order to investigate phylogenetic relationships of the family sciuridae living in japan, we sequenced partial regions (379 bases) of mitochondrial 12s rrna genes in six species of japanese and other asian squirrels. phylogenetic trees constructed by sequence data indicated that two genera of flying squirrels (petaurista and pteromys) were clustered in a group distinct from non-flying squirrels, suggesting a possible monophyletic relationships of these flying squirrels. the evolutionary distan ... | 1996 | 8940915 |
| fitness consequences of hoarding behaviour in the eurasian red squirrel. | hoarding increases food availability during periods of scarcity, and therefore should enhance fitness. although short-term advantages of hoarding have been described for birds, effects over an animal's lifetime have not yet been documented. here, we report that in the red squirrel, sciurus vulgaris, individuals which recovered many cached tree seeds increased their body mass and were more likely to survive the spring breeding season than those that recovered fewer seeds. there was no significant ... | 1995 | 8587886 |
| an investigation into the health and welfare of red squirrels, sciurus vulgaris, involved in reintroduction studies. | the threats posed by parapoxvirus infection, metabolic bone disease and coccidiosis to the reintroduction of red squirrels into thetford chase were investigated by making blood biochemical, radiological and parasitological examinations on the squirrels before they were released and on resident squirrels. red squirrels found dead in thetford chase were examined post mortem by parasitological, electron microscopical and radiological techniques. parapoxvirus infection was the probable cause of deat ... | 1995 | 8578648 |
| [great degree of homology between the ancestral karyotype of squirrels (rodents) and that of primates and carnivores]. | the karyotype of 7 species of sciurinae representative of 6 tribes were compared: atlantoxerus getulus, menetes berdmorei, callosciurus flavimanus, heliosciurus gambianus, sciurus vulgaris, eutamias sibiricus, and marmota monax. homoeologies between almost all chromosome segments were found. numerous similarities with the karyotypes of certain primates and carnivora were observed. a presumed ancestral karyotype of the sciurinae is proposed. | 1984 | 6335365 |
| isolation in cell culture of a poxvirus from the red squirrel (sciurus vulgaris). | 1984 | 6322409 | |
| parapoxvirus infection of the red squirrel (sciurus vulgaris). | 1981 | 6275598 | |
| tahyna virus in squirrels/sciurus vulgaris l. | 1966 | 6006819 | |
| [reproduction and endocrine cycles in squirrels (sciurus vulgaris)]. | 1966 | 6006496 | |
| [hyperinfestation of squirrels (sciurus vulgaris) by an anoplure, neohematopinus sciuri jancke, 1931]. | 2003 | 5950217 | |
| [demonstration of enamel structure and of v. korff's dentin on a total preparation on rodent incisors (sciurus vulgaris)]. | 1968 | 5718923 | |
| the role of small rodents and hedgehogs in a natural focus of tick-borne encephalitis. | the role of small rodents and hedgehogs in the circulation of tick-borne encephalitis in natural foci in the tribec region of czechoslovakia has been studied. isolation of virus from the blood of apodemus flavicollis, clethrionomys glareolus and erinaceus roumanicus, as well as the demonstration of antibodies in the sera of these mammals and of a. sylvaticus, microtus arvalis and sciurus vulgaris, showed that these mammals had been in contact with the virus in recent years. the proportion of pos ... | 1967 | 5298543 |
| the autecology of small rodents and insectivores of the tribec mountain range. | small rodents and insectivores have become the main reservoirs of tick-borne encephalitis virus. in order, therefore, to demonstrate the dynamic and structural changes occurring in a natural focus of tick-borne encephalitis, information has been collected on the distribution, habitat, life-cycle, population density and extent of tick infestation of the rodents and insectivores that inhabit the tribec region and adjacent parts of the hronský inovec mountains. the following mammals are discussed: ... | 1967 | 5298539 |
| [study of the n-terminal amino acid sequence of the myoglobin of the squirrel (sciurus vulgaris) and of the otter (lutra lutra)]. | 2006 | 4790765 | |
| [properties of visual elements of the cortex and superior colliculus of the squirrel sciurus vulgaris]. | 2007 | 4756722 | |
| [comparative study of the physico-chemical properties and chemical structure of the hemoglobin and myoglobin of sciurus vulgaris protein]. | 1973 | 4709881 | |
| [study of the n-terminal amino acid sequence of the polypeptide chains of the hemoglobin of sciurus vulgaris protein]. | 1972 | 4662621 | |
| investigations on spontaneous arterial pathology and serum cholesterol in the squirrel (sciurus vulgaris). | 1974 | 4460223 | |
| [chromosomal phylogeny of 7 species of sciurinae]. | the sequence of chromosomal rearrangements that leads to the karyotypes of living species of sciurinae is hardly compatible with a dichotomic evolution. the most probable hypothesis is that of a populational chromosomal evolution: the different lineages would have been isolated successively from an ancestral population in which several chromosomal rearrangements would have spread to more or less important fractions of the population. the proposed order in the succession of these isolations (marm ... | 1985 | 3874584 |
| experimental infection of the squirrel (sciurus vulgaris) and the muskrat (ondatra zibethica) with tahyna virus (california group, bunyaviridae). | two squirrels aged 16 weeks and three muskrats aged 24 weeks were subcutaneously infected with a dose of 400 smicld50 of the extraneurally passaged "236" strain of tahyna virus. viremia was detected in one squirrel (48 and 96 hours post infection) and in two muskrats (24 and 48 hours p.i.). seroconversion was demonstrated by plaque-reduction neutralization test (prnt) 21 days p.i. in all animals. | 1987 | 3297950 |
| identification, using isoenzyme electrophoresis and monoclonal antibodies, of leishmania isolated from humans and wild animals of ecuador. | six strains of leishmania isolated from wild mammals and humans on the pacific coast of ecuador were identified by isoenzyme electrophoresis and by their reactivity patterns to a cross-panel of specific monoclonal antibodies using a radioimmune binding assay. single isolates from sciurus vulgaris, potos flavus, and tamandua tetradactyla were identified as leishmania amazonensis. three other strains, isolated from cutaneous lesions of humans, were identified as leishmania panamensis. | 1989 | 2919726 |
| experimental infection of squirrels sciurus vulgaris by monkey pox virus. | 1989 | 2574948 | |
| an immunohistochemical study of the gastro-entero-pancreatic endocrine cells in the alimentary tract of the korean tree squirrel, sciurus vulgaris corea. | the regional distribution and relative frequencies of gastrointestinal endocrine cells were studied immunohistochemically in the gastrointestinal mucosa of korean tree squirrels. seven kinds of endocrine cells were identified in this study. although a large number of 5-hydroxytryptamine-immunoreactive cells were seen throughout the gastrointestinal tract, they were most predominant in the duodenum. a moderate number of glucagon-immunoreactive cells which were restricted to the cardia and fundus ... | 1991 | 1821436 |
| the nasal apparatus of the red squirrel (sciurus vulgaris l.) embryo at the stage of the fully formed chondrocranium. | the nasal apparatus of the squirrel embryo at the optimum stage of the chondrocranium displays simple (though not always primitive) features and individual structures developed largely as in other rodents and even in insectivores. primitive features include the presence of a cartilago paraseptalis communis and probably the simplicity of the olfactory labyrinth, whose main support in the region as a whole is ethmoturbinale i, whose dorsal and ventral lamella divide off the basic recesses; anterio ... | 1991 | 1790345 |
| [responses of squirrel visual cortex neurons to patterned visual stimuli]. | the responses of visual cortical neurons to patterned visual stimuli were studied in squirrel sciurus vulgaris. the direction selective, orientation-selective and non-selective neurons were observed. most direction-selective and non-selective neurons were sensitive to high speeds of stimulus movement--hundreds deg/s. the direction-selective neurons exhibited their selectivity at such high speeds in spite of the short time of the stimulus movement through the receptive field. orientation-selectiv ... | 1975 | 1207803 |
| [emmonsia crescencse emmons et jellison, 1960- a common cause of adiaspiromycosis in squirrels (sciurus vulgaris l.) in czechoslovakia]. | 1976 | 1035789 | |
| [new faunal and biological observations on ticks in abruzzo]. | ticks collected during the years 1975-76 in abruzzo (prov. l'aquila and chieti) italy are reported. the following species have been identified: ixodes canisuga, ixodes frontalis, ixodes hexagonus, ixodes ricinus, dermacentor marginatus, haemaphysalis sulcata, rhipicephalus bursa, rhipicephalus sanguineus, hyalomma marginatum. new hosts are: felis catus for ixodes canisuga; scolopax rusticola, motacilla flava, corvus cornix for ixodes frontalis; sciurus vulgaris for haemaphysalis punctata; garrul ... | 1976 | 1032325 |
| [organization of the receptive fields of the superior colliculus neurons of the squirrel sciurus vulgaris]. | studies have been made on the reaction of single neurons of the superior colliculus to stationary and moving visual stimuli in immobilized squirrels. the main bulk of collicular units (59%) is not directionally selective, 11%--exhibit high directional selectivity and 30%--were found to be relatively selective. most of the cells (85%) "prefer" high speed of stimulus motion. optimal speed for these neurons is equal to 30--100 degree/sec. testing by a stationary light spot (0.5degree in diameter), ... | 1976 | 941588 |
| nutritional osteodystrophy in a free-living red squirrel (sciurus vulgaris). | 1977 | 836605 |