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ursodeoxycholic acid in the ursidae: biliary bile acids of bears, pandas, and related carnivores.the biliary bile acid composition of gallbladder bile obtained from six species of bears (ursidae), the giant panda, the red panda, and 11 related carnivores were determined by reversed phase liquid chromatography and gas chromatography-mass spectrometry. bile acids were conjugated solely with taurine (in n-acyl linkage) in all species. ursodeoxycholic acid (3 alpha, 7 beta-dihydroxy-5 beta-cholan-24-oic acid) was present in all ursidae, averaging 1-39% of biliary bile acids depending on the spe ...19938263415
suppression and repression in discrepant self-other ratings: relations with thought control and cardiovascular reactivity.individual differences in self-other disagreement may tap phenomena that have been notoriously difficult to assess. for example, subjects who believe they possess a trait while their acquaintances disagree may be exhibiting suppression. further, subjects who deny a trait while acquaintances believe it is present may be displaying repression. in the first study, both subjects and their closest friends rated the subject's hostility level. suppressors and repressors were expected to exhibit enhance ...19938151503
individual differences in the wegner rebound effect: evidence for a moderator variable in thought rebound following thought suppression.wegner, schneider, carter, and white in 1987 found that attempts to suppress thoughts of a white bear produced even greater preoccupation with that stimulus--a rebound effect. this effect was investigated in exp. 1 using both wegner's white bear stimulus and a more personally meaningful stimulus (an upcoming test). the rebound effect was not observed with either stimulus. exp. 2 was conducted to examine the hypothesis that this failure to replicate wegner, et al.'s rebound effect reflected indiv ...19938332689
levels and congener pattern of pcbs in arctic fox, alopex lagopus, in svalbard.levels and congener pattern of polychlorinated biphenyls (pcbs) were determined in samples of subcutaneous fat and liver from 27 polar foxes, alopex lagopus, caught in svalbard during the winter 1983-1984. in all the samples analysed the composition of individual pcb congeners was studied by comparison with 12 individual pcb congeners (iupac nos. 28, 52, 101, 118, 138, 153, 170, 180, 183, 194, 206 and 209). in addition, the pcb congeners nos. 99, 105, 114, 156 and 157 were determined in the fat ...199315091776
chronic thought suppression.we conducted several tests of the idea that an inclination toward thought suppression is associated with obsessive thinking and emotional reactivity. initially, we developed a self-report measure of thought suppression through successive factor-analytic procedures and found that it exhibited acceptable internal consistency and temporal stability. this measure, the white bear suppression inventory (wbsi), was found to correlate with measures of obsessional thinking and depressive and anxious affe ...19947861307
phylogenetic relationships of bears (the ursidae) inferred from mitochondrial dna sequences.the phylogenetic relationships among some bear species are still open questions. we present here mitochondrial dna sequences of d-loop region, cytochrome b, 12s rrna, trna(pro), and trna(thr) genes from all bear species and the giant panda. a series of evolutionary trees with concordant topology has been derived based on the combined data set of all of the mitochondrial dna sequences, which may have resolved the evolutionary relationships of all bear species: the ancestor of the spectacled bear ...19947697192
chlorinated hydrocarbon contaminants in arctic marine mammals.by 1976, the presence of chlorinated hydrocarbon contaminants (chcs) had been demonstrated in fur seal (callorhinus ursinus), ringed seal (phoca hispida), hooded seal (cystophora cristata), bearded seal (erignathus barbatus), walrus (obdobenus rosmarus divergens), beluga (delphinapterus leucas), porpoise (phocoena phocoena) and polar bear (ursus maritimus) in various parts of the arctic. in spite of this early interest, very little subsequent research on contaminants in arctic marine mammals was ...19947973601
an integrated analytical method for determination of polychlorinated aryl methyl sulfone metabolites and polychlorinated hydrocarbon contaminants in biological matrices.a simple column chromatography method was developed for separation and cleanup in the determination of chlorinated hydrocarbon contaminants and their methyl sulfone (meso2-) metabolites in biological tissues. the method was validated for determination of 11 polychlorinated biphenyls (pcbs), 15 tetra- to heptachloro 3- and 4-meso2-pcbs, 3-meso2-dde, and tris(4-chlorophenyl)-methanol spiked to herring gull egg, smelt, and polar bear liver and adipose tissue using gas chromatography with electron-c ...19958633767
persistent chlorinated cyclodiene compounds in ringed seal, polar bear, and human plasma from northern quebec, canada: identification and concentrations of photoheptachlor. 199522200230
catalytic and immunologic characterization of hepatic and lung cytochromes p450 in the polar bear.the arctic ocean is subject to considerable influx of anthropogenic pollutants including halogenated organic compounds. the polar bear (ursus maritimus) is at the top of the arctic marine food web and is an ideal species for monitoring the level and distribution of contaminants in the arctic ecosystem. as the first step in the development of a biological method for assessing the functional exposure of polar bears to xenobiotics, biochemical studies were undertaken to characterize polar bear cyto ...19957748195
concentrations of polychlorinated dibenzo-p-dioxins, dibenzofurans and non-ortho substituted biphenyls in polar bear milk from svalbard (norway).polychlorinated dibenzo-p-dioxins (pcdd), dibenzofurans (pcdf) and non-ortho substituted biphenyls (pcb, cb) were determined in 6 polar bear milk samples from svalbard (norway). for these compounds, no data for polar bears have been reported before from this region. most of the pcdd/pcdf congeners were found at detectable levels. concentrations expressed as 2,3,7,8-tcdd equivalents (nordic model) were in the order of 1-3 pg/g(-1) fat (0.2-1.6 pg ml(-1) milk) which is comparable with ringed and h ...199515091475
comparative anatomy of the cardiac foramen ovale in cats (felidae), dogs (canidae), bears (ursidae) and hyaenas (hyaenidae).the structure of the foramen ovale from 16 species representing 4 carnivore families, the felidae, canidae, ursidae and hyaenidae, was studied using the scanning electron microscope. the felidae were represented by 9 domestic cat fetuses (felis catus), 2 snow leopard neonates (uncia uncia), an ocelot neonate (leopardus pardalis), 2 lion neonates (panthera leo), a panther neonate (panthera pardus) and 3 tigers (neofelis tigris), comprising 2 fetuses and a neonate. the canidae were represented by ...19957649822
microsatellite analysis of population structure in canadian polar bears.attempts to study the genetic population structure of large mammals are often hampered by the low levels of genetic variation observed in these species. polar bears have particularly low levels of genetic variation with the result that their genetic population structure has been intractable. we describe the use of eight hypervariable microsatellite loci to study the genetic relationships between four canadian polar bear populations: the northern beaufort sea, southern beaufort sea, western hudso ...19957663752
preliminary results of fasting on the kinetics of organochlorines in polar bears (ursus maritimus).we determined concentrations of polychlorinated biphenyls (pcbs), chlordanes (chlors), chlorobenzenes (cbzs), hexachlorocyclohexanes (hchs), and dichlorodiphenyltrichloroethane (ddt) and its metabolites (ddd and dde) in the tissues of individual polar bears (ursus maritimus) before and after a lengthy period of fasting. polar bears are an ideal model for such studies. they undergo one of the most extreme fasts known for any mammal and are located at the top of a long food chain, thus biomagnific ...19957892579
geographical distribution and identification of methyl sulphone pcb and dde metabolites in pooled polar bear (ursus maritimus) adipose tissue from western hemisphere arctic and subarctic regions.the geographical distribution of methyl sulphone (meso2-) pcb and dde metabolites is unknown for any species in any region. in this study, pooled male polar bear (ursus maritimus) adipose samples from 12 arctic and subarctic regions from the bering sea to the greenland sea were analyzed for pcbs, dde, and their meso2-metabolites. each adipose pool contained from three to 27 lipid extracts prepared on an equal fat basis. the total (s-) meso2-pcb and meso2-dde levels were generally higher in the e ...19957892578
the comforting substrate and the right brain.the author tested the hypothesis that the comforting substrate is located in the right parietal area of the brain. sixty subjects (39 women, 21 men) were given two forced-choice tasks treated as comparison experiments. given the choice between two identical bright red balls (one on the left and one on the right), only 20% of the right-handed subjects chose the left ball (p < .01). given the choice between identical stuffed, white bears, which were described as grieving and urgently in need of co ...19958535387
jaws catheter exchange: an alternative method of exchanging coronary interventional devices.this study describes an alternative method of exchanging over-the-wire (otw) angioplasty catheters over standard length coronary guide wires. exchange was facilitated with a specially designed catheter stripper, jaws (microvena, white bear lake, mn). jaws is a disposable instrument similar to an electrician's wire stripper whose cutting blades automatically center the wire before cutting the catheter shaft. one hundred seventy catheter exchanges were performed in 93 patients. catheter extraction ...19968958439
use of fluoxetine for the treatment of stereotypical pacing behavior in a captive polar bear.stereotypical behaviors are common in captive animals, particularly captive polar bears. effects of oral administration of fluoxetine on chronic stereotypical and typical behaviors in a captive polar bear were monitored. fluoxetine treatment terminated stereotypic pacing behavior, facial tic, and huffing/coughing activity. the expression of typical polar bear behaviors was not affected by fluoxetine treatment, although the proportion of time spent engaged in typical behaviors changed during the ...19968870749
versatility of the microvena snare in pediatric interventional cardiac catheterization.improved catheter and device technology has allowed the practice of pediatric interventional catheterization to expand in recent years. one such example of technologic advancement has been the development of an intravascular snare by microvena (white bear lake, mn). we present three patients in which the snare was effectively used to perform definitive transcatheter therapy and avoid the need of more invasive surgical treatment. we believe that the snare device significantly decreased our fluoro ...19968721706
immunoquantitation and microsomal monooxygenase activities of hepatic cytochromes p4501a and p4502b and chlorinated hydrocarbon contaminant levels in polar bear (ursus maritimus).contamination of the arctic ecosystem by anthropogenic compounds has resulted in exposure of polar bear (ursus maritimus) to lipophilic chlorinated hydrocarbon contaminants (chcs) accumulated through the marine food web. liver samples were collected from 16 adult male polar bears in the canadian arctic and subjected to chemical analysis for chcs and metabolites, determination of alkoxyresorufin o-dealkylase activities, and immunoquantitation of cytochrome p450 (cyp) protein levels. we report on ...19968661337
a beta-associated cerebral angiopathy and senile plaques with neurofibrillary tangles and cerebral hemorrhage in an aged wolverine (gulo gulo).in this study of an aged wolverine (gulo gulo), we document neuropathologic lesions (cerebral amyloid angiopathy (caa), neuritic plaques (nps), neurofibrillary tangles (nfts), and granulovacuolar degeneration strikingly similar to those present in aging and alzheimer's disease (ad), with the additional finding of concurrent cerebral hemorrhage. a beta immunoreactive cerebral amyloid angiopathy and senile plaques (neuritic and diffuse) were present throughout the cerebral cortex and hippocampus. ...19968744405
carboxy terminal of beta-amyloid deposits in aged human, canine, and polar bear brains.immunocytochemistry, using antibodies specific for different carboxy termini of beta-amyloid. a beta 40 and a beta 42(43), was used to compare beta-amyloid deposits in aged animal models to nondemented and demented alzheimer's disease human cases. aged beagle dogs exhibit diffuse plaques in the absence of neurofibrillary pathology and the aged polar bear brains contain diffuse plaques and phf-1-positive neurofibrillary tangles. the brains of nondemented human subjects displayed abundant diffuse ...19968744406
phylogeography of brown bears (ursus arctos) of alaska and paraphyly within the ursidae.complete nucleotide sequences of the mitochondrial cytochrome b, trna(prolime), and trna(threonine) genes were described for 166 brown bears (ursus arctos) from 10 geographic regions of alaska to describe natural genetic variation, construct a molecular phylogeny, and evaluate classical taxonomies. dna sequences of brown bears were compared to homologous sequences of the polar bear (maritimus) and of the sun bear (helarctos malayanus), which was used as an outgroup. parsimony and neighbor-joinin ...19968744762
a phylogeny of the bears (ursidae) inferred from complete sequences of three mitochondrial genes.complete sequences of dna are described for the cytochrome b trna(thr) and trna(pro) genes of mitochondria of four extant species of ursids and compared to sequences of four other species of ursids previously studied by us. phylogenetic analyses indicate that the giant panda and the spectacled bear are the basal taxa of the ursid radiation. the ursines, a group which includes the sun bear, sloth bear, american black bear, asiatic black bear, brown bear, and polar bear, experienced a rapid radiat ...19968744769
serological evidence of morbillivirus infection in polar bears (ursus maritimus) from alaska and russia.one-hundred-and-ninety-one samples of blood serum collected from 186 polar bears (ursus maritimus) between 1987 and 1992 were analysed for morbillivirus antibodies. the samples were collected in the bering, chukchi and east siberian seas. sixty-eight samples (35.6 per cent) had morbillivirus antibody titres > 5; the percentage of positive samples ranged from 26.2 to 46.2 per cent from year to year. the proportions of adults, sub-adults and cubs which were seropositive were 43.9, 35.7 and 37.9 pe ...19968807784
estimation of accumulated dose of radiation by the method of esr-spectrometry of dental enamel of mammals.esr-spectrometry was used to investigate radiation-induced paramagnetic centers in enamel of mammals: carnivores (polar bear and fox), ungulates (reindeer, european bison, moose), and man. values at half the microwave power saturation of the radiation signal, p1/2, evaluated at room temperature, was found to range from 16 to 26 mw for animals and man. a new approach to discrimination of the radiation induced signal from the total esr spectrum of reindeer enamel is proposed. 'dose-response' depen ...19969022192
serologic survey of trichinellosis in wild mammals kept in a mexico city zoo.a serologic survey of trichinella infection was carried out to determine the prevalence of this parasitosis among wild mammals kept in captivity at the chapultepec zoo. this was prompted by the necropsy finding of a heavy trichinella infection in a canadian polar bear (ursus maritimus) that had been kept at the zoo for more than 11 years. the parasites recovered were identified as t. nativa (t2). a serologic study based on elisa and western blot analysis was performed in serum samples from two p ...19969017871
immunoquantitation of cytochromes p450 1a and p450 2b and comparison with chlorinated hydrocarbon levels in archived polar bear liver samples.the present study examined the utility of an immunoblot method for quantitation of cytochrome p450 isozymes in archived liver samples as a bioassay of exposure to halogenated hydrocarbons. hepatic microsomes were prepared from 44 archived polar bear (ursus maritimus) liver homogenates that had been stored at approximately -40 degrees c for 9-10 years and analyzed on blots probed with antibodies to rat cytochromes p450 1a1 and p450 2b1. the results revealed a positive correlation between cytochro ...19979134680
fatal hepatic sarcocystosis in two polar bears (ursus maritimus).fatal hepatic sarcocystosis was diagnosed in 2 polar bears from a zoo in anchorage, alaska. gross lesions were icterus and systemic petechiae. marked microscopic lesions were detected only in the liver and included severe random necrotizing hepatitis with hemorrhage. only asexual stages of an apicomplexan parasite were detected within hepatocytes, and rare extracellular zoites were seen in foci of necrosis. the parasite divided by endopolygeny, and occasionally merozoites formed rosettes around ...19979194839
acute chagas' cardiopathy in a polar bear (ursus maritimus) in guadalajara, mexico.we report a 24-year-old female polar bear (ursus maritimus) who contracted chagas' infection at the guadalajara zoo, in jalisco, méxico, and died of acute chagas' carditis 15 days later. the histopathological findings are described, as well as the presence of triatomids (triatoma longipennis usinger) infected with trypanosoma cruzi collected within 5 meters from the place where the animal lived in the city of guadalajara.19979219444
identification and differentiation of bear bile used in medicinal products in taiwan.one hundred eighty-three suspect bear bile used in medicinal products, collected in taiwan as gall bladders or dried powder forms, were analyzed using ftir, hptlc, and hplc techniques to identify whether they are indeed bear bile. those confirmed were further examined to determine whether the observed analytical parameters can be reliably used for source inference, i.e., differentiating products among north american black bear, farmed asiatic black bear, polar bear, etc. our data suggested that ...19979304828
trichinella in arctic, subarctic and temperate regions: greenland, the scandinavian countries and the baltic states.the transmission and occurrence of trichinella spp according to the zoogeography of different climatic conditions, socioeconomy and human activity are discussed. comparing arctic, subarctic and temperate regions, it appears that the species of trichinella present, the composition of the fauna and the human activity are all very important interacting factors affecting epidemiology. in greenland, where only sylvatic trichinellosis is present, the high prevalence in wildlife appears closely connect ...19979656341
an empirical evaluation of genetic distance statistics using microsatellite data from bear (ursidae) populations.a large microsatellite data set from three species of bear (ursidae) was used to empirically test the performance of six genetic distance measures in resolving relationships at a variety of scales ranging from adjacent areas in a continuous distribution to species that diverged several million years ago. at the finest scale, while some distance measures performed extremely well, statistics developed specifically to accommodate the mutational processes of microsatellites performed relatively poor ...19979409849
reversible immobilization of free-ranging polar bears with medetomidine-zolazepam-tiletamine and atipamezole.the objective of this study was to determine if the potent alpha 2 agonist, medetomidine, and its specific antagonist, atipamezole, could be effectively used to immobilize polar bears (ursus maritimus). specifically, our goal was to develop a drug combination containing medetomidine that addressed some of the problems such as prolonged recovery time, non-reversibility, and poor analgesia that have been identified with the currently preferred drug combination, zolazepamtiletamine (telazol or zole ...19979249708
organochlorines in polar bears (ursus maritimus) at svalbard.a comprehensive survey on organochlorine (oc) contaminants in polar bears at svalbard has been undertaken. subcutaneous tissue, blood and milk have been sampled from anesthetized free-ranging bears of both sexes and different ages in the period from 1990 to 1994. a number of sexually mature females have been fitted with satellite transmitters which make it possible to follow their reproductive behaviour pattern. we report on contamination levels and pattern of pcb congeners, chlordanes, ddt-comp ...199715093456
catheter closure of secundum atrial septal defects.catheter occlusion of atrial septal defects has its roots in the 1950s, with early devices being implanted during closed-heart surgery without cardiopulmonary bypass. for the past 20 years, various catheter-delivered devices have undergone testing and refinement. designs have included single- and double-disk prostheses, with a variety of materials, delivery systems, and techniques. in this monograph, the history of atrial septal defect occluders and their evaluation, results, and prognoses will ...19979456481
chlorinated hydrocarbon contaminants in polar bears from eastern russia, north america, greenland, and svalbard: biomonitoring of arctic pollution.adipose tissue samples from polar bears (ursus maritimus) were obtained by necropsy or biopsy between the spring of 1989 to the spring of 1993 from wrangel island in russia, most of the range of the bear in north america, eastern greenland, and svalbard. samples were divided into 16 regions corresponding as much as possible to known stocks or management zones. concentrations of dieldrin (diel), 4,4'-dde (dde), sum of 16 polychlorinated biphenyl congeners (sigma pcb), and sum of 11 chlordane-rela ...19989680529
thought suppression produces a rebound effect with analogue post-traumatic intrusions.attempts to suppress traumatic material may be involved in the development and maintenance of post-traumatic stress disorder (ptsd). in order to investigate this possibility, analogue post-traumatic intrusions were induced in normal participants by means of a distressing film. for comparison, a second film was used to induce intrusions about polar bears. it was hypothesized that the suppression of these intrusions would produce an immediate decrease but a delayed increase ("rebound effect") in t ...19989648331
agenesis of a radius in a polar bear cub (ursus maritimus).a polar bear (ursus maritimus) cub, delivered by a cesarean section, was diagnosed with congenital agenesis of the radius on the basis of clinical presentation and radiology. a specific etiology could not be ascertained. agenesis of the radius has not been previously reported in any nondomestic species.19989638629
enantioselective gas chromatography/mass spectrometry of methylsulfonyl pcbs with application to arctic marine mammals.four different commercially available cyclodextrin (cd) capillary gas chromatography (gc) columns were tested for the enantioselective separation of nine environmentally persistent atropisomeric 3- and 4-methylsulfonyl pcbs (meso2-cbs). the selected columns contained cyclodextrins with various cavity diameters (beta- or gamma-cd), which were methylated and/or tert-butyldimethylsilylated (tbdms) in the 2,3,6-o-positions. the beta-cd column with tbdms substituents in all of the 2,3,6-o-positions w ...19989751025
is polar bear hair fiber optic?new direct measurement of high optical attenuation rates in polar bear hairs--2-8 db/mm in the visible--and reanalysis of the data of tributsch et al. [sol. energy mater. 21, 219 (1990)] seem to rule out the uv waveguiding proposed by grojean et al. [appl. opt. 19, 339 (1980)]. the case against fiber-optic polar bear hairs is summarized, and four conditions are given that any variation of the model of grojean et al. would have to satisfy.199818273269
female pseudohermaphrodite polar bears at svalbard.during research on polar bears (ursus maritimus) at svalbard in april 1996, we captured two yearlings with a normal vaginal opening and a 20 mm penis containing a baculum. the penis was located caudal to the location in a normal male and was concealed within the vaginal opening by a single pair of labia. the urethral opening was situated laterally about 5 mm from the distal end of the penis. neither of the yearlings showed signs of a y chromosome, so both bears were regarded as female pseudoherm ...19989813850
man and polar bear in svalbard: a solvable ecological conflict?the objective of this study is twofold. first, it is to assess the nature and magnitude of the polar bear-human conflict with respect to injuries to man and bear. second, a major concern has been to minimize injurious interactions in order to safeguard the people who live and work in the arctic, and, at the same time, secure the future of the polar bear in one of the last relatively unspoiled habitats on earth for big carnivores. from 1971 to 1995, approximately 80 bears were involved in serious ...199810093337
n-terminal heterogeneity of parenchymal and cerebrovascular abeta deposits.the goals of this study were twofold: to determine whether species differences in abeta n-terminal heterogeneity explain the absence of neuritic plaques in the aged dog and aged bear in contrast to the human; and to compare abeta n-terminal isoforms in parenchymal vs cerebrovascular abeta (cva) deposits in each of the species, and in individuals with alzheimer disease (ad) vs nondemented individuals. n-terminal heterogeneity can affect the aggregation, toxicity, and stability of abeta. the human ...19989600199
localization and comparative toxicity of methylsulfonyl-2,5- and 2,6-dichlorobenzene in the olfactory mucosa of mice.several methylsulfonyl (meso2) metabolites formed from chlorinated aromatic hydrocarbons have been identified in human milk, lung, and body fat, as well as in the tissues of baltic grey seals and arctic polar bears. the tissue localization and nasal toxicity of two methylsulfonyl-substituted dichlorobenzenes (dicl-meso2-b), with the chlorine atoms in the 2,5-, and 2,6- positions, were investigated in female nmri and c57b1 mice. using tape-section autoradiography, animals dosed i.v. with 14c-labe ...199910367349
bear-inflicted human injury and fatality.this review attempts to summarize credible scientific information, and to dispel myths, regarding bear attacks. publications in the scientific literature were sought through a medline search and by reviewing the bibliographies of related books and scientific articles. personal experience and interviews with authorities were also used in preparation of this review, although only published articles or books are cited. this is a summary of case series reported or observed elsewhere. bear-inflicted ...199910442155
comparative anatomy of the radial sesamoid bone in the polar bear (ursus maritimus), the brown bear (ursus arctos) and the giant panda (ailuropoda melanoleuca).since we have clarified the manipulation mechanism using the radial sesamoid (rs) in the giant panda (ailuropoda melanoleuca), our aim in this study is to examine the position, shape and function of the rs morphologically, and to observe the attachment to the rs of the m. abductor pollicis longus and the m. opponens pollicis in the other ursidae species. so, we focused on the carpus and manus of the polar bear (ursus maritimus) and the brown bear (ursus arctos) in this study. the rs was tightly ...199910487229
aujeszky's disease in captive bears.five of eight bears died during an outbreak of aujeszky's disease in a travelling circus in the north of spain. the bears had been fed on a diet which included raw pigs' heads. one of three himalayan bears and a kodiak bear died acutely with signs of the disease. one of four polar bears died acutely without signs, another died with signs of aujeszky's disease while it was being treated, and a third died with enteritis and disseminated intestinal coagulation some time later without showing signs ...199910573192
absence of trypanosomes in polar bears (ursus maritimus) from svalbard. 199910576628
genetic structure of the world's polar bear populations.we studied genetic structure in polar bear (ursus maritimus) populations by typing a sample of 473 individuals spanning the species distribution at 16 highly variable microsatellite loci. no genetic discontinuities were found that would be consistent with evolutionarily significant periods of isolation between groups. direct comparison of movement data and genetic data from the canadian arctic revealed a highly significant correlation. genetic data generally supported existing population (manage ...199910583821
acute fish liver intoxication: report of three cases.the livers of some larger fish such as shark, tuna and seabass have been reported to be responsible for a peculiar poisoning causing headaches and desquamation. this type of poisoning can also be induced by ingestion of the livers of the sea whale, the polar bear and the seal. since these animals contain an extremely large quantity of vitamin a in their livers and the symptoms of poisoning in the patients resembled those of patients with acute hypervitaminosis a, the poisoning was believed to ha ...199910584420
rapid radiation events in the family ursidae indicated by likelihood phylogenetic estimation from multiple fragments of mtdna.the bear family (ursidae) presents a number of phylogenetic ambiguities as the evolutionary relationships of the six youngest members (ursine bears) are largely unresolved. recent mitochondrial dna analyses have produced conflicting results with respect to the phylogeny of ursine bears. in an attempt to resolve these issues, we obtained 1916 nucleotides of mitochondrial dna sequence data from six gene segments for all eight bear species and conducted maximum likelihood and maximum parsimony anal ...199910508542
spatial and temporal trends and effects of contaminants in the canadian arctic marine ecosystem: a review.recent studies have added substantially to our knowledge of spatial and temporal trends of persistent organic pollutants and heavy metals in the canadian arctic marine ecosystem. this paper reviews the current state of knowledge of contaminants in marine biota in the canadian arctic and where possible, discusses biological effects. the geographic coverage of information on contaminants such as persistent organochlorines (ocs) (pcbs, ddt- and chlordane-related compounds, hexachlorocyclohexanes, t ...199910466228
effects of inedible, manipulable objects on captive bears.bears in captivity often show abnormal behaviors such as stereotypies and periods of excessive inactivity. most of the research aimed at reducing abnormal behaviors in bears has focused on feeding enrichment. however, the effects of feeding enrichment only seem to last as long as it takes a bear to consume the food. this study investigated the effects of inedible, manipulable objects on bears. two polar bears (ursus maritimus) received plastic floats. a sloth bear (melursus ursinus) and a specta ...199916363951
roald amundsen: a study in rivalry, masochism and paranoia.the author suggests that freud was intrigued by those who explored the still unknown regions of the globe; in 1928 he received a letter from a colleague who knew he was interested in the psychology of polar explorers, asking him to comment on some strange visualizations that had haunted roald amundsen, the great polar explorer, when during one of his arctic expeditions he was attacked and nearly mauled to death by a polar bear. freud emphasised the quality of resignation and surrender inherent i ...199910643576
anesthesia of polar bears (ursus maritimus) with zolazepam-tiletamine, medetomidine-ketamine, and medetomidine-zolazepam-tiletamine.a 1:1 combination (by weight) of zolazepam and tiletamine is the drug of choice for anesthetizing polar bears (ursus maritimus), but recovery time is prolonged when additional doses are administered. recoveries may last 24 hr and may threaten the health of the bears. we compared the anesthetic effects of zolazepam-tiletamine (zt) with those of medetomidine-ketamine (mk) and medetomidine-zolazepam-tiletamine (mzt) in 93 free-ranging polar bears. the mzt combination was administered in smaller dos ...199910572857
parachutes, polar bears, and patients. 199910510610
cardiopulmonary response of anesthetized polar bears to suspension by net and sling.since 1995, at least three polar bears (ursus maritimus) have died in the area of churchill (manitoba, canada) as a direct result of being suspended in a net during helicopter-assisted translocations. to assess and improve methods of suspending anesthetized polar bears, we conducted a study during november 1997 to determine the cardiopulmonary responses of eight captive polar bears to suspension by net and by sling. each bear was anesthetized on two occasions in which the sequence of activities ...199910479090
transcatheter closure of a patent foramen ovale following mitral valve replacement.we report the successful closure of a postoperative patent foramen ovale in a patient who underwent coronary artery bypass grafting and mitral valve replacement for severe mitral insufficiency. the postoperative course was complicated by severe hypoxemia due to a large patent foramen ovale. the patient underwent transcatheter closure with the das angel wings transcatheter occluder (microvena corporation, white bear lake, mn) with immediate improvement.199910475443
suppression and ritualistic behaviour in normal participants.previous research has shown that normal and abnormal ritualistic behaviours do not differ in content. rather, the differences between both categories of rituals pertain to characteristics such as frequency, intensity, discomfort and resistance. this study sought to investigate whether thought suppression is linked to these characteristics.199910389600
hypospadias in a polar bear (ursus maritimus).corrective surgery on a 1.5-yr-old male polar bear (ursus maritimus) with hypospadias included amputation of the vestigial penis, bilateral orchiectomy with scrotal ablation, and distal perineal urethrostomy. hypospadias in other species is a congenital deformity that may be caused by extra- and intrauterine factors resulting in a disruption of the testosterone balance during urethral development, but the causative mechanism in this bear is unknown. the urethrostomy site was functional without c ...199910367656
rickets in two hand-reared polar bear (ursus maritimus) cubs.two polar bear (ursus maritimus) cubs born at the denver zoological gardens were abandoned by a primiparous mother. lethargic and extremely chilled, the cubs were transported to the zoo hospital for intensive care and hand rearing. both cubs developed rickets. dietary changes were instituted, and both cubs completely recovered with the exception of a bowed right femur (genu varum) in the female cub.199910367655
feature centrality: naming versus imagining.being white is central to whether we call an animal a "polar bear," but it is fairly peripheral to our concept of what a polar bear is. we propose that a feature is central to category naming in proportion to the feature's category validity--the probability of the feature, given the category. in contrast, a feature is conceptually central in a representation of the object to the extent that the feature is depended on by other features. further, we propose that naming and conceptual centrality ar ...199910355241
subcutaneous implantation of satellite transmitters with percutaneous antennae into male polar bears (ursus maritimus).male polar bears (ursus maritimus) have not been successfully instrumented with satellite transmitters because they readily shed collar-mounted transmitters. seven male polar bears were captured on the pack ice off the northern coast of alaska and surgically implanted with satellite transmitters with percutaneous antennae into the subcutaneous space of the dorsal cervical region. transmitters failed prematurely with lifetimes of 30-161 days (mean = 97 days). efforts to relocate implanted bears a ...199910749436
comparative physiologic effects of telazol, medetomidine-ketamine, and medetomidine-telazol in captive polar bears (ursus maritimus).the cardiopulmonary effects of three drug combinations in polar bears (ursus maritimus) were studied. in 1995, five adult polar bears received i.m. injections of either 8.2 +/- 1.3 mg/kg of telazol or a combination of 159 +/- 34 microg/kg of medetomidine with 4 +/- 0.8 mg/kg of ketamine in a crossover design. significantly higher mean arterial pressure, lower heart rate, and lower partial pressure of arterial oxygen (pao2) occurred with medetomidine-ketamine. in 1996, six adult polar bears were ...199910749435
removal of a ruptured, detached, and entrapped angioplasty balloon after coronary stenting.entrapment of balloon catheters after coronary angioplasty or stent implantation is a complication during these procedures. we describe the removal of a ruptured angioplasty balloon which had become disconnected from the proximal shaft of the balloon catheter and entrapped after coronary stenting by using a 4 mm amplatz "goose neck" microsnare retrieval system (microvena, white bear lake, minnesota). the retrieval was accomplished without any complications. retrieval systems should be on hand in ...200010731273
the angel wings das devices for atrial septal defect closure.the angel wings das device (microvena corporation, white bear lake, mn) is a self-centering, nitinol-polyester prosthesis with two square-shaped disks and a customized delivery catheter. the implantation success rate for atrial septal defects (asds) was 92% and 94% in the phase i and ii trials in the united states, and 97% and 100% for patients with patent foramen ovale (pfo). residual shunts in the phase ii united states trials at 24 hours by transthoracic echocardiography are as follows: for p ...200011096653
white bears and other elusive intrusions. assessing the relevance of thought suppression for obsessional phenomena.according to recent research, deliberate suppression of unwanted thoughts may result in a paradoxical increase in their frequency. recent cognitive-behavioral theories of obsessive-compulsive disorder now consider active thought suppression to be a crucial factor in the pathogenesis of obsessions. however, there are considerable inconsistencies in the results of studies investigating the thought suppression paradox that make it difficult to apply findings to obsessional problems. furthermore, ma ...200010881386
the handling of polar bears in the western hudson bay. 200010813629
biological transport and mammal to mammal transfer of organochlorines in arctic fauna.ringed seal (phoca hispida) is assumed to be the most important and common prey of polar bears (ursus maritimus). however, during a scientific survey in the ice area of the northern barents sea east of svalbard in june 1995, an unexpectedly high number of polar bears were observed feeding on harp seal (phoca groenlandica) carcasses. samples of both harp and ringed seals were obtained and organochlorine (oc) occurrence and pattern in these two potential polar bear prey species were determined. si ...200011285735
determination of toxaphenes in fish and marine mammals.an analytical method for the determination of toxaphene in biological materials using gas chromatography with an electron capture detector (gc-ecd) has been established and validated for three single congeners (chlorinated bornanes (chb) 26, 50 and 62). the analytical method was based on a method for determination of pcb, ddt and other chlorinated pesticides. to include toxaphene congeners an extra step, adsorption chromatography on silica columns, was introduced to separate the pesticides from ...200010819223
geographical differences and time trends of persistent organic pollutants in the arctic.geographical and temporal trends of total pcbs (sigmapcbs) and hexachlorocyclohexanes (sigmahchs) have been examined in polar bear (ursus maritimus) adipose tissue and ringed seal (phoca hispida) blubber along a transect from alaska to svalbard and northern norway/western russia. pcb concentrations in polar bear show a strong west to east trend with higher levels in east greenland, svalbard. in ringed seal, highest pcb levels were found at two sites near the russian coast. sigmahchs levels in ri ...200010720717
an assessment of selenium to mercury in greenland marine animals.information on mercury and selenium molar relation in muscle, liver and kidney tissue of greenland marine animals is presented. in the majority of the samples selenium was present in a molar surplus to mercury. this was most clear in molluscs, crustaceans, fish and seabirds. a 1:1 molar ratio was found in tissues of marine mammals with high mercury concentrations (above approx. 10 nmol/g). this was most clearly demonstrated for liver and kidney tissue of polar bear and for ringed seal with high ...200010682353
ecotoxicological risk assessment of environmental pollutants in the arctic.concentrations of such persistent organic pollutants (pops) as polychlorinated biphenyls (pcbs) are high in certain arctic animal species. the polar bear, arctic fox, and glaucous gull may be exposed to pcb levels above lowest-observed-adverse-effect-level (loael) values for adverse effects on reproduction in mammals and birds. however, the dioxin-like congeners seem to be major contributors to the reproductive effects of pcbs and the relative concentrations of these congeners are low in polar b ...200010720719
cloning and sequence analysis of the extracellular region of the polar bear (ursus maritimus) luteinizing hormone receptor (lhr), follicle stimulating hormone receptor (fshr), and prolactin receptor (prlr) genes and their expression in the testis of the black bear (ursus americanus).male black bears undergo seasonal changes in testicular activity. the testes are fully functional from may through july, regress from july through december, and recrudesce from january until may. the mechanisms responsible for the initiation of testicular recrudescence in the bear are unknown. the objectives of this study were to: (1) clone and sequence a substantial fragment of the extracellular portion of the luteinizing hormone receptor (lhr: 646 bp) and follicle stimulating hormone receptor ...200010618652
autochthonous and imported trichinella isolates in germany.the study of trichinella isolates from wildlife in germany revealed the presence of trichinella spiralis and trichinella britovi in wild boars and foxes. t spiralis was detected in meat products imported from spain, which is one of the two endemic areas of domestic trichinellosis in the european union: it was also detected in meat from a grizzly bear marketed in alaska, and trichinella nativa was detected in a polar bear from the berlin zoo. these results stress the importance of examining for t ...200010622607
adaptation of the muscles of mastication to the flat skull feature in the polar bear (ursus maritimus).the muscles of mastication of the polar bear (ursus maritimus) and those of the brown bear (u. arctos) were examined by anatomical approach. in addition, the examination of the skull was carried out in the polar bear, brown bear and giant panda (ailuropoda melanoleuca). in the polar bear, the rostro-ventral part of the superficial layer of the m. masseter possessed the abundant fleshy portion folded in the rostral and lateral directions like an accordion. moreover, the rostro-medial area of the ...200010676883
geographical differences of zinc, cadmium, mercury and selenium in polar bears (ursus maritimus) from greenland.muscle, liver, and kidney tissues from 100 polar bears (ursus maritimus), caught in the avanersuaq area, north-west greenland, and ittoqqortoormiit area, central-east greenland, were analysed for zinc, cadmium, mercury and selenium. the zinc concentrations in muscle and liver were higher than in kidney. mean zinc concentrations ranged from 19.7 to 76.0 micrograms/g (all data are presented as geometric means on a wet wt. basis). the presented cadmium concentrations by area and age groups were all ...200010682354
temporal and spatial trends of persistent organochlorines in greenland walrus (odobenus rosmarus rosmarus).persistent organochlorines [pcbs, ddt and chlordane related compounds, dieldrin, toxaphene, hexachlorocyclohexane (hch), chlorobenzenes] were determined in blubber of atlantic walrus (odobenus rosmarus rosmarus) in 1978 and 1988 from the avanersuaq (thule) region of north-west greenland and in 1989 from ittoqqortoormiit (scoresbysund) in east greenland. lowest concentrations of organochlorines (ocs) were found in the samples from the avanersuaq region while much higher levels of all compounds, e ...200010682357
organochlorines in top predators at svalbard--occurrence, levels and effects.alarmingly high polychlorinated biphenyl (pcb) levels have been found in the top predators such as glaucous gull (larus hyperboreus) and polar bear (ursus maritimus) at svalbard [gabrielsen, g.w., skaare, j.u., polder, a., bakken, v., 1995. chlorinated hydrocarbons in glaucous gull (larus hyperboreus). sci. total environ. 160/161, 337-346; bernhoft, a., skaare, j.u., wiig, o., 1997. organochlorines in polar bears (ursus maritimus) at svalbard. environ. pollut. 95, 159-175; henriksen, e.o., gabri ...200010720718
possible immunotoxic effects of organochlorines in polar bears (ursus maritimus) at svalbard.associations between immunoglobulin g (igg) levels and the organochlorine contaminants (ocs) polychlorinated biphenyls (pcbs), chlordanes, 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (dde), hexachlorobenzene (hcb), and hexachlorocyclohexanes (hchs) in blood plasma from polar bears caught at svalbard were determined. the blood samples were collected from free-living polar bears of different age and sex between 1991 and 1994. the igc concentration increased with age and was significantly higher ...200010777247
phylogeography of mitochondrial dna variation in brown bears and polar bears.we analyzed 286 nucleotides of the middle portion of the mitochondrial cytochrome b gene of 61 brown bears from three locations in alaska and 55 polar bears from arctic canada and arctic siberia to test our earlier observations of paraphyly between polar bears and brown bears as well as to test the extreme uniqueness of mitochondrial dna types of brown bears on admiralty, baranof, and chichagof (abc) islands of southeastern alaska. we also investigated the phylogeography of brown bears of alaska ...200010837161
2,3-dpg-hb complex: a hypothesis for an asymmetric binding.this study was undertaken to test the symmetry of 2,3-diphosphoglycerate (2,3-dpg) binding site in hemoglobin (hb). from arnone's study [a. arnone, nature (london) 237 (1972) 146] the 2,3-dpg binding site is located at the top of the cavity, that runs through the center of the deoxy-hb molecule. however, it is possible that this symmetry reported by arnone, for crystals of 2,3-dpg-hb complex, might not be conserved in solution. in this paper, we report the 31p nuclear magnetic resonances of the ...200010852312
chemical characterization of milk oligosaccharides of the polar bear, ursus maritimus.two trisaccharides, three tetrasaccharides, two pentasaccharides, one hexasaccharide, one heptasaccharide, one octasaccharide and one decasaccharide were isolated from polar bear milk samples by chloroform/methanol extraction, gel filtration, ion exchange chromatography and preparative thin-layer chromatography. the oligosaccharides were characterized by 1h-nmr as follows: the saccharides from one animal: gal(alpha1-3)gal(beta1-4)glc (alpha3'-galactosyllactose), fuc(alpha1-2)gal(beta1-4)glc (2'- ...200010913842
pharmacokinetics and tissue residues of telazol in free-ranging polar bears.a pharmacokinetic and tissue residue study was conducted to assess the risks associated with human consumption of polar bears in arctic canada that have been exposed to the immobilizing drug telazol, a mixture of tiletamine hydrochloride and zolazepam hydrochloride. twenty-two bears were remotely injected with about 10 mg/kg of telazol. following immobilization, serum samples were collected serially at regular intervals until the bears awakened. sixteen of the bears were relocated and killed und ...200011085426
the occurrence and ecology of trichinella in marine mammals.trichinella in marine mammals has a circumpolar arctic distribution and a narrow range of host species. it is commonly found in polar bears (ursus maritimus), and increasingly in walruses (odobenus rosmarus) where it presents a significant zoonotic hazard. this has resulted in the implementation of food safety programs in some arctic communities to test harvested walrus meat for trichinella larvae prior to consumption. trichinella has been reported infrequently in bearded seals (erignathus barba ...200011099845
serum concentrations of vitamin d metabolites, vitamins a and e, and carotenoids in six canid and four ursid species at four zoos.nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. the species analyzed included: african wild dog (lycaon pictus), arctic fox (alopex lagopus), gray wolf (canis lupus), maned wolf (chrysocyon brachyurus), mexican wolf (canis lupus baleiyi), red wolf (canis rufus), brown bear (ursus arctos), polar bear (ursus maritimus), spectacled bear (tremarctos ornatus), and sun bear (ursus malayanus). diet information was collected for these animals ...200111137448
relationships between plasma levels of organochlorines, retinol and thyroid hormones from polar bears (ursus maritimus) at svalbard.associations were determined between retinol and the thyroid hormones thyroxine (t4) and triiodothyronine (t3), respectively, and the organochlorine contaminants (ocs) polychlorinated biphenyls (pcbs), 1, 1-dichloro-2,2-bis-(4-chlorophenyl)ethylene (dde), hexachlorobenzene (hcb), and hexachlorocyclohexanes (hchs) in blood plasma from polar bears (ursus maritimus) caught at svalbard. the blood samples were collected from free-ranging polar bears of different age and sex in 1991-1994. the retinol ...200111245393
nuclear deviation in hepatic parenchymal cells on sinusoidal surfaces in arctic animals.in normal rat and human, most of the nuclei of hepatic parenchymal cells are centrally located in the cytoplasm. however, it is reported that the nuclei of hepatic parenchymal cells are situated at a deviated position on sinusoidal surfaces under pathological situations such as chronic hepatitis, hepatocellular carcinoma, adenomatous hyperplasia, or regeneration. during a study on the mechanism of extreme vitamin a-accumulation in hepatic stellate cells of arctic animals including polar bears, a ...200111482455
ultrastructural characteristics of nurse cell-larva complex of four species of trichinella in several hosts.the nurse cell-larva complex of nematodes of the genus trichinella plays an important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. the ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with t. nativa (a walrus and a polar bear), t. spiralis (horses and humans), t. pseudospiralis (a laboratory mouse) and t. papuae (a laboratory mouse) were examined. analysis w ...200111484383
brucella sp. antibodies in polar bears from svalbard and the barents sea.a prevalence of 5.4% of anti-brucella sp. antibodies was found in plasma samples from 297 polar bears (ursus maritimus) from svalbard and the barents sea. plasma was tested by the classical brucellosis tests slow agglutination of wright (saw), edta modified saw and rose bengal test, as well as by an indirect protein a elisa. only samples classified as positive in all tests were regarded as containing anti-brucella sp. antibodies. a significant west to east increase in the proportion of bears wit ...200111504225
bear mauling: a descriptive review.provide a descriptive review of bear and human interactions in the united states.200111768451
commentary: abeta n- terminal isoforms: critical contributors in the course of ad pathophysiology.the assessment of protein or amino acid variations across evolution allows one to glean divergent features of disease-specific pathology. within the alzheimer's disease (ad) literature, extensive differences in abeta processing across cell lines and evolution have clearly been observed. in the recent past, increased levels of amyloid beta abeta1-42 have been heralded to be what distinguishes whether one is prone to the development of ad [59]. however, observations in naturally occurring, non-tra ...200112214065
global distribution of perfluorooctane sulfonate in wildlife.here we report, for the first time, on the global distribution of perfluorooctanesulfonate (pfos), a fluorinated organic contaminant. pfos was measured in the tissues of wildlife, including, fish, birds, and marine mammals. some of the species studied include bald eagles, polar bears, albatrosses, and various species of seals. samples were collected from urbanized areas in north america, especially the great lakes region and coastal marine areas and rivers, and europe. samples were also collecte ...200111348064
organochlorine burdens in blood of ringed and bearded seals from north-western svalbard.ringed seal (phoca hispida) and bearded seal (erignathus barbatus) are the main prey of polar bears (ursus maritimus), and information on organochlorines (ocs) in these pinniped species is important to understand the transport, fate and effects of persistent organic pollutants in the arctic ecosystem. thus, ocs were analysed in blood samples of bearded and ringed seals from the coastal ecosystem of the north-western svalbard archipelago (kongsfjorden, 78.55degrees n). the relative contribution o ...200111444300
concentrations and interactions of selected essential and non-essential elements in ringed seals and polar bears of arctic alaska.in this study, we evaluated concentrations of twelve essential and non-essential elements (as, cd, co, cu, pb, mg, mn, hg, mo, se, ag, and zn) in tissues of ringed seals (phoca hispida) and polar bears (ursus maritimus) of arctic alaska (usa). all samples were collected between 1995-97 in conjunction with subsistence harvests. the essential elements are reported to help develop reference ranges for health status determination and to help assess known or suspected interactions affecting toxicoses ...200111763734
musculoskeletal system of the neck of the polar bear (ursus maritimus) and the malayan bear (helarctos malayanus).the gross anatomical study was undertaken in the musculoskeletal system of the neck of the polar bear, and the findings were compared with those of the malayan bear. the musculus splenius and the m. trapezius were well-developed in the polar bear. the long neck of the polar bear consisted mainly of the m. splenius with the m. biventer cervicis and the m. complexus lying tightly underneath. the cervical vertebrae possessed huge ventral tubercle in the ventral part of the transverse process in the ...200111206987
extraversion and the rebound effect after thought suppression.83 participants thought about a white bear before or after trying to suppress the idea. there was no rebound effect (more expression of white-bear thoughts after than before suppression) for either introverts or extraverts.200111597062
endocrine disruption in sexual differentiation and puberty. what do pseudohermaphroditic polar bears have to do with the practice of pediatrics?what do pseudohermaphroditic polar bears and girls with premature breast development have in common? hormones. sexual differentiation and the initiation of secondary sexual characteristics, such as breast growth, are both under the control of the sex hormones estrogen and androgen. abnormal differentiation of the internal or external genitalia in bears and early onset of breast development in girls also may have a common element--exposure to environmental hormones.200111579671
innervation of the lower eyelid in relation to blepharoplasty and midface lift: clinical observation and cadaveric study.ectropion or scleral show resulting from weakness of the lower eyelids is not uncommon after lower blepharoplasty or midface lift via blepharoplasty incision. denervation of the pretarsal orbicularis oculi muscle (oom) attributes to such complications. the authors analyzed 102 patients who underwent midface lift via lower blepharoplasty incision for the past 3 years and investigated the motor nerve innervation of the lower oom in 20 cadavers. they encountered two cases of ectropion attributed to ...200111756795
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