Search Results - (Author, Cooperation:M. Ramsay)

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  1. 1
    Staff View
    Publication Date:
    2018-04-14
    Publisher:
    BMJ Publishing
    Electronic ISSN:
    2044-6055
    Topics:
    Medicine
    Keywords:
    Open access, Epidemiology
    Published by:
    http://group.bmj.com/

    Latest Papers from Table of Contents or Articles in Press
  2. 2
    Staff View
    Publication Date:
    2018-01-10
    Publisher:
    BMJ Publishing Group
    Print ISSN:
    0017-5749
    Electronic ISSN:
    1468-3288
    Topics:
    Medicine
    Published by:
    http://www.bmj.com/

    Latest Papers from Table of Contents or Articles in Press
  3. 3
    C. Rotimi ; A. Abayomi ; A. Abimiku ; V. M. Adabayeri ; C. Adebamowo ; E. Adebiyi ; A. D. Ademola ; A. Adeyemo ; D. Adu ; D. Affolabi ; G. Agongo ; S. Ajayi ; S. Akarolo-Anthony ; R. Akinyemi ; A. Akpalu ; M. Alberts ; O. Alonso Betancourt ; A. M. Alzohairy ; G. Ameni ; O. Amodu ; G. Anabwani ; K. Andersen ; F. Arogundade ; O. Arulogun ; D. Asogun ; R. Bakare ; N. Balde ; M. L. Baniecki ; C. Beiswanger ; A. Benkahla ; L. Bethke ; M. Boehnke ; V. Boima ; J. Brandful ; A. I. Brooks ; F. C. Brosius ; C. Brown ; B. Bucheton ; D. T. Burke ; B. G. Burnett ; S. Carrington-Lawrence ; N. Carstens ; J. Chisi ; A. Christoffels ; R. Cooper ; H. Cordell ; N. Crowther ; T. Croxton ; J. de Vries ; L. Derr ; P. Donkor ; S. Doumbia ; A. Duncanson ; I. Ekem ; A. El Sayed ; M. E. Engel ; J. C. Enyaru ; D. Everett ; F. M. Fadlelmola ; E. Fakunle ; K. H. Fischbeck ; A. Fischer ; O. Folarin ; J. Gamieldien ; R. F. Garry ; S. Gaseitsiwe ; R. Gbadegesin ; A. Ghansah ; M. Giovanni ; P. Goesbeck ; F. X. Gomez-Olive ; D. S. Grant ; R. Grewal ; M. Guyer ; N. A. Hanchard ; C. T. Happi ; S. Hazelhurst ; B. J. Hennig ; C. Hertz ; Fowler ; W. Hide ; F. Hilderbrandt ; C. Hugo-Hamman ; M. E. Ibrahim ; R. James ; Y. Jaufeerally-Fakim ; C. Jenkins ; U. Jentsch ; P. P. Jiang ; M. Joloba ; V. Jongeneel ; F. Joubert ; M. Kader ; K. Kahn ; P. Kaleebu ; S. H. Kapiga ; S. K. Kassim ; I. Kasvosve ; J. Kayondo ; B. Keavney ; A. Kekitiinwa ; S. H. Khan ; P. Kimmel ; M. C. King ; R. Kleta ; M. Koffi ; J. Kopp ; M. Kretzler ; J. Kumuthini ; S. Kyobe ; C. Kyobutungi ; D. T. Lackland ; K. A. Lacourciere ; G. Landoure ; R. Lawlor ; T. Lehner ; M. Lesosky ; N. Levitt ; K. Littler ; Z. Lombard ; J. F. Loring ; S. Lyantagaye ; A. Macleod ; E. B. Madden ; C. R. Mahomva ; J. Makani ; M. Mamven ; M. Marape ; G. Mardon ; P. Marshall ; D. P. Martin ; D. Masiga ; R. Mason ; M. Mate-Kole ; E. Matovu ; M. Mayige ; B. M. Mayosi ; J. C. Mbanya ; S. A. McCurdy ; M. I. McCarthy ; H. McIlleron ; S. O. Mc'Ligeyo ; C. Merle ; A. O. Mocumbi ; C. Mondo ; J. V. Moran ; A. Motala ; M. Moxey-Mims ; W. S. Mpoloka ; C. L. Msefula ; T. Mthiyane ; N. Mulder ; G. Mulugeta ; D. Mumba ; J. Musuku ; M. Nagdee ; O. Nash ; D. Ndiaye ; A. Q. Nguyen ; M. Nicol ; O. Nkomazana ; S. Norris ; B. Nsangi ; A. Nyarko ; M. Nyirenda ; E. Obe ; R. Obiakor ; A. Oduro ; S. F. Ofori-Acquah ; O. Ogah ; S. Ogendo ; K. Ohene-Frempong ; A. Ojo ; T. Olanrewaju ; J. Oli ; C. Osafo ; O. Ouwe Missi Oukem-Boyer ; B. Ovbiagele ; A. Owen ; M. O. Owolabi ; L. Owolabi ; E. Owusu-Dabo ; G. Pare ; R. Parekh ; H. G. Patterton ; M. B. Penno ; J. Peterson ; R. Pieper ; J. Plange-Rhule ; M. Pollak ; J. Puzak ; R. S. Ramesar ; M. Ramsay ; R. Rasooly ; S. Reddy ; P. C. Sabeti ; K. Sagoe ; T. Salako ; O. Samassekou ; M. S. Sandhu ; O. Sankoh ; F. S. Sarfo ; M. Sarr ; G. Shaboodien ; I. Sidibe ; G. Simo ; M. Simuunza ; L. Smeeth ; E. Sobngwi ; H. Soodyall ; H. Sorgho ; O. Sow Bah ; S. Srinivasan ; D. J. Stein ; E. S. Susser ; C. Swanepoel ; G. Tangwa ; A. Tareila ; O. Tastan Bishop ; B. Tayo ; N. Tiffin ; H. Tinto ; E. Tobin ; S. M. Tollman ; M. Traore ; M. J. Treadwell ; J. Troyer ; M. Tsimako-Johnstone ; V. Tukei ; I. Ulasi ; N. Ulenga ; B. van Rooyen ; A. P. Wachinou ; S. P. Waddy ; A. Wade ; M. Wayengera ; J. Whitworth ; L. Wideroff ; C. A. Winkler ; S. Winnicki ; A. Wonkam ; M. Yewondwos ; T. sen ; N. Yozwiak ; H. Zar
    American Association for the Advancement of Science (AAAS)
    Published 2014
    Staff View
    Publication Date:
    2014-06-21
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Africa ; Disease/*genetics ; England ; Genetics, Medical/trends ; Genome-Wide Association Study/*trends ; Genomics/*trends ; Health ; Humans ; National Institutes of Health (U.S.) ; United States
    Published by:
    http://www.aaas.org/

    Latest Papers from Table of Contents or Articles in Press
  4. 4
    Staff View
    Publication Date:
    2014-12-04
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Africa ; Africa South of the Sahara ; Asia/ethnology ; Europe/ethnology ; Genetic Variation/*genetics ; Genetics, Medical/*trends ; Genome, Human/*genetics ; Genomics/*trends ; Humans ; Risk Factors ; Selection, Genetic/genetics
    Published by:
    http://www.nature.com/

    Latest Papers from Table of Contents or Articles in Press
  5. 5
    Ramsay, M. M. ; Pipkin, F. Broughton ; Rubin, P. C.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1993
    Staff View
    ISSN:
    1471-0528
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Medicine
    Notes:
    Objective To study cardiovascular responses to noradrenaline during early pregnancy.Design Administration of incremental intravenous infusions of noradrenaline under basal conditions.Setting University Hospital, Nottingham.Subjects Nineteen women admitted for termination of pregnancy in first or second trimester and 18 nonpregnant women as control subjects.Interventions Recordings of blood pressure and heart rate responses during the infusion of noradrenaline. Blood samples taken before, during and after the infusion.Main outcome measures Evoked responses of systolic and diastolic blood pressure and heart rate at steady state during the noradrenaline infusion. Plasma catecholamine concentrations measured by high performance liquid chromatography.Results There were no significant differences between the evoked pressor responses to noradrenaline in pregnancy compared to the nonpregnant state, but there was a lesser bradycardia in response to a standardised change in blood pressure. Neither basal plasma catecholamine concentrations nor those achieved during infusion of noradrenaline differed between pregnant and nonpregnant women. Thirty minutes after discontinuance of the infusion there was a persistent elevation of heart rate in all women, although plasma catecholamine concentrations had returned to basal levels. In pregnant women, systolic and diastolic blood pressures were also elevated at this time, compared to preinfusion levels.Conclusion Cardiovascular regulatory mechanisms are altered in pregnancy with a diminution in the bradycardic response to a pressor challenge evoked by noradrenaline and a delayed recovery from that challenge.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1471-0528.1993.tb15216.x

    Articles: DFG German National Licenses
  6. 6
    Taylor, E. M. ; Parker, S. ; Ramsay, M. P.

    Oxford, UK and Boston, USA : Blackwell Publishers Ltd.
    Published 1998
    Staff View
    ISSN:
    1467-8519
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Medicine
    Philosophy
    Notes:
    Aims: To assess patient receipt of written information. To ensure patients understand the written information about a resuscitation policy and to determine whether they disapproved of or had concerns about the policy.Methods: All admissions to four wards of the hospital were approached for an interview. A set questionnaire was asked by one of 2 interviewers.Results: 72% of 572 admissions were interviewed. Refusal accounted for only 2 of the people not interviewed. 11% were unable to advocate for themselves by reason of mental incompetence, inability to communicate or impairment secondary to their illness.Of the 401 interviewed only 49% recalled receiving the patient information booklet. Few patients (17%) recalled reading the information in the patient information booklet. They were all then given the paragraph about the hospital’s resuscitation policy. 352 were asked their understanding and only 61% demonstrated that they understood the paragraph. 91% of all 401 patients approved of the hospital having the option of DNR orders. 31% of people however had concerns related to DNR orders. These are discussed.Conclusions: Many acutely unwell patients are unable to advocate for themselves. Written information is a poor method of communicating with patients. There was limited receipt of the information and many misunderstood the paragraph about the hospitals resuscitation policy. There was a wide range of patient thoughts and concerns expressed.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/1467-8519.00093

    Articles: DFG German National Licenses
  7. 7
    RAMSAY, M. A. E. ; COLVIN, M. P. ; TAYLOR, T. H. ; GIL-RODRIGUEZ, J. A. ; MORRIS, J. L. ; WYLIE, I. G.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1976
    Staff View
    ISSN:
    1365-2044
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1365-2044.1976.tb11969.x

    Articles: DFG German National Licenses
  8. 8
    SAVEGE, T. M. ; RAMSAY, M. A. E. ; CURRAN, J. P. J. ; COTTER, J. ; WALLING, P. T. ; SIMPSON, B. R.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1975
    Staff View
    ISSN:
    1365-2044
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1365-2044.1975.tb00951.x

    Articles: DFG German National Licenses
  9. 9
    Ramsay, M. A. E.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1972
    Staff View
    ISSN:
    1365-2044
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1365-2044.1972.tb08244.x

    Articles: DFG German National Licenses
  10. 10
    Van Hougenhouck-Tulleken, W. ; Chan, I. ; Hamada, T. ; Thornton, H. ; Jenkins, T. ; McLean, W.H.I. ; McGrath, J.A. ; Ramsay, M.

    Oxford, UK : Blackwell Science Ltd
    Published 2004
    Staff View
    ISSN:
    1365-2133
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Medicine
    Notes:
    Background  Lipoid proteinosis (LiP) is a rare autosomal recessive disorder characterized by a hoarse voice, warty skin infiltration and scarring. Mutations within the extracellular matrix protein 1 (ECM1) gene cause LiP. Since the early 1970s it has been recognized that South Africa has one of the largest groups of LiP patients worldwide, suggesting a probable founder effect. As LiP patients present with considerable clinical variability, this group of patients offers a unique opportunity for genotype–phenotype correlation.Objectives  To assess the clinical features and the molecular basis of LiP in patients from the Namaqualand area of the Northern Cape province of South Africa and to examine molecular evidence for a founder effect.Subjects and methods  The LiP patient cohort consisted of 29 Coloured patients from Namaqualand and a further seven Caucasoid patients from other areas of South Africa. The control group included 100 healthy geographically and ethnically matched individuals from Namaqualand. Samples were collected after informed consent and with ethics committee approval from the University of the Witwatersrand. LiP patients were examined clinically and a structured recording sheet was completed. A brief neurological evaluation was also performed. The LiP founder effect was investigated at the molecular level by ECM1 mutation detection and haplotype analysis.Results  The most consistent clinical signs for a diagnosis of LiP in this group were a hoarse voice and thickened sublingual frenulum leading to restricted tongue movement. Homozygosity for a nonsense mutation in exon 7 of the ECM1 gene, Q276X, was identified in all patients (Coloured and Caucasoid). Despite this genetic homogeneity, considerable clinical variability in skin presentation and psychiatric involvement was observed. Haplotype analysis using markers from a 9·98-Mb region around the ECM1 locus confirmed the founder effect with a founder core haplotype, 19-Q276X-12 (ND1-ECM1-D1S2343), in all but four LiP-associated alleles (n = 58). A LiP carrier rate of 1 in 9 was observed among the 100 Namaqualand controls, predicting a LiP incidence of 1 in 324 in this community.Conclusions  Although several consistent clinical features in LiP patients homozygous for the Q276X mutation in the ECM1 gene were observed, there remains considerable clinical variability. This suggests the action of genetic and environmental modifiers of disease severity. Strong molecular evidence supports a single founder effect for the high prevalence of LiP in South Africans, both Coloured and Caucasoid.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1111/j.1365-2133.2004.06076.x

    Articles: DFG German National Licenses
  11. 11
    Bannerman, D. M. ; Good, M. A. ; Butcher, S. P. ; Ramsay, M. ; Morris, R. G. M.

    [s.l.] : Nature Publishing Group
    Published 1995
    Staff View
    ISSN:
    1476-4687
    Source:
    Nature Archives 1869 - 2009
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Notes:
    [Auszug] After a brief habituation phase, male Lister rats were implanted with minipumps for chronic intracerebroventricular (i.c.v.) infusion of AP5 (30 mM, 0.5 ul h"1) or artificial cerebro-spinal fluid (aCSF) and trained in a watermaze to find a fixed, hidden escape platform (experiment 1). Rats treated ...
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1038/378182a0

    Articles: DFG German National Licenses
  12. 12
    LYTOLLIS, J. ; RAMSAY, M. M. ; TEESDALE, R. R.

    [s.l.] : Nature Publishing Group
    Published 1963
    Staff View
    ISSN:
    1476-4687
    Source:
    Nature Archives 1869 - 2009
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Notes:
    [Auszug] Fig. 1. Top left, no laser action: peak current, 11.5 amp; top right, laser threshold; peak current, 12.5 amp; bottom left, laser action in overdrive condition; peak current, 19 amp; bottom right, laser action in overdrive condition; peak current, 〉30 amp. In all photographs the upper trace ...
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1038/1991083a0

    Articles: DFG German National Licenses
  13. 13
    Staff View
    ISSN:
    0888-7543
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1006/geno.1993.1050

    Articles: DFG German National Licenses
  14. 14
    Staff View
    ISSN:
    0888-7543
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Medicine
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1016/0888-7543(90)90446-2

    Articles: DFG German National Licenses
  15. 15
    Staff View
    ISSN:
    0006-291X
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Biology
    Chemistry and Pharmacology
    Physics
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1016/0006-291X(91)91803-K

    Articles: DFG German National Licenses
  16. 16
    Ramsay, M. M.
    Springer
    Published 1973
    Staff View
    ISSN:
    1572-817X
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Electrical Engineering, Measurement and Control Technology
    Physics
    Notes:
    Abstract Interest in fibre-optic communication systems was aroused by Kao and Hockham in 1966. This survey endeavours to relate how the concept has grown within the United Kingdom from that inception. The work is reviewed from the standpoint of a systems engineer, but briefly covers the components vital to fibre-optic communication systems and mentions the more fundamental studies on which all other aspects have been based.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF02057125

    Articles: DFG German National Licenses
  17. 17
    Staff View
    ISSN:
    1432-0703
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Energy, Environment Protection, Nuclear Power Engineering
    Medicine
    Notes:
    Abstract. 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 (ΣPCB), and sum of 11 chlordane-related compounds and metabolites (ΣCHL) were determined. In order to minimize the effect of age, only data for adults (320 bears age 5 years and older) was used to compare concentrations among regions. Concentrations of ΣPCB were 46% higher in adult males than females, and there was no significant trend with age. Concentrations of ΣCHL were 30% lower in adult males than females. Concentrations of ΣPCB, ΣCHL, and DDE in individual adult female bears were standardized to adult males using factors derived from the least-square means of each sex category, and geometric means of the standardized concentrations on a lipid weight basis were compared among regions. Median geometric mean standardized concentrations (lipid weight basis) and ranges among regions were as follows: ΣPCB, 5,942 (2,763–24,316) μg/kg; ΣCHL, 1,952 (727–4,632) μg/kg; DDE, 219 (52–560) μg/kg; DIEL, 157 (31–335) μg/kg. Geometric mean ΣPCB concentrations in bears from Svalbard, East Greenland, and the Arctic Ocean near Prince Patrick Island in Canada were similar (20,256–24,316 μg/kg) and significantly higher than most other areas. Atmospheric, oceanic, and ice transport, as well as ecological factors may contribute to these high concentrations of ΣPCB. ΣCHL was more uniformly distributed among regions than the other CHCs. Highest ΣCHL concentrations were found in southeastern Hudson Bay, which also had the highest DDE and DIEL concentrations. In general, concentrations of ΣCHL, DDE, and DIEL were higher in eastern than western regions, suggesting an influence of North American sources. Average ΣPCB concentrations in bears from the Canadian Arctic were similar to those in 1982–84, while average ΣCHL and DDE concentrations were 35–44% lower and DIEL was 90% lower. However, the significance of these temporal trends during the 1980s is not conclusive because of the problems of comparability of data.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s002449900387

    Articles: DFG German National Licenses
  18. 18
    Gisel, E.G. ; Alphonce, E. ; Ramsay, M.
    Springer
    Published 2000
    Staff View
    ISSN:
    1432-0460
    Keywords:
    Key words: Functional feeding skills — Chewing efficiency — Chewing duration — Chewing strokes — Motor planning — Interobserver reliability — Concurrent validity — Deglutition — Deglutition disorders
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Notes:
    Abstract. Eating impairments (dysphagia) in children with cerebral palsy (CP) have been well documented. However, individual components of ingestion, such as the feeding skills of eating and drinking and their relationship to oral-motor planning skills (praxis), remain largely undetermined. The purpose of the present study was to examine functional feeding and oral praxis skills in a group of children with CP and mild eating impairment and to compare their skills with a group of age-matched controls. As well, interobserver reliabilities and concurrent validity of these tests were examined to determine their reliability and to what extent they may be measuring similar constructs. Twenty-seven children with CP and 21 age-matched controls, aged 4.0–16 years, participated in this study. Two oral praxis tests (OFMF and OPT) and two standard ingestive skills tests (GVA and FFAm) were administered to each child. Children with CP scored consistently and significantly lower on the OFMF than controls (p 〈 0.001); similar results were achieved on the OPT (p 〈 0.001). Children with CP had difficulty with items where there was a high demand for repetition and smooth sequencing. On the ingestive skills tests children with CP took significantly longer for chewing a hard solid food texture than controls (p 〈 0.001), and functional feeding skills were also significantly poorer than in controls. Interrater reliability coefficients for the OPT and OFMF were excellent (all ICCs 〉 0.90). There was high concurrent validity between the OPT and OFMF (r= 0.90, p 〈 0.0001). The correlations for the FFAm and GVA tests were somewhat weaker (r=−0.54, p 〈 0.0001). Correlations were negative; as functional feeding scores increased (improved), chewing time decreased (improved). Excellent reliable and valid assessment instruments are available to the practicing clinician. They cover a wide range of oral-motor performance and, so, must be used judiciously and for the purpose that they have been developed.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s004550000033

    Articles: DFG German National Licenses
  19. 19
    Staff View
    ISSN:
    1432-1203
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Medicine
    Notes:
    Summary The allele frequency of a Taq 1 γ-globin gene restriction fragment length polymorphism (RFLP) is reported in ten population groups. In four African populations the 3.0 kb RFLP is common (50/132 {ie90-1} chromosomes), whereas it is completely absent in six European/Asian populations (0/277 {ie90-2} chromosomes). This Taq 1 RFLP is thus a specific African population marker.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00278792

    Articles: DFG German National Licenses
  20. 20
    Ramsay, M. A. ; Hobson, K. A.
    Springer
    Published 1991
    Staff View
    ISSN:
    1432-1939
    Keywords:
    Polar bears ; δ13C ; Fasting ; Arctic food web ; Ursus maritimus
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Biology
    Notes:
    Summary The mean stable-carbon isotope ratios (δ13C) for polar bear (Ursus maritimus) tissues (bone collagen −15.7‰, muscle −17.7‰, fat −24.7‰) were close to those of the same tissues from ringed seals (Phoca hispida) (−16.2‰, −18.1‰, and −26.1‰, respectively), which feed exclusively from the marine food chain. The δ13C values for 4 species of fruits to which polar bears have access when on land in summer ranged from −27.8 to −26.2‰, typical of terrestrial plants in the Arctic. An animal's δ13C signature reflects closely the δ13C signature of it's food. Accordingly, the amount of food that polar bears consume from terrestrial food webs appears negligible, even though some bears spend 1/3 or more of each year on land during the seasons of greatest primary productivity.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00318328

    Articles: DFG German National Licenses