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881.
882.
Emma L. B. Barrett Winifred Boner Ellis Mulder Pat Monaghan Simon Verhulst David S. Richardson 《Journal of avian biology》2012,43(6):571-576
Bird populations provide excellent systems to investigate variation in longevity in the wild since individuals can often be monitored over their lifetime. A number of recent studies suggest that the dynamics of protective telomere chromosome caps (telomere length and rate of loss) are indicative of biological state and potentially useful as indicators of future longevity. Currently, Terminal Restriction Fragment (TRF) analysis and relative quantitative PCR (qPCR) are used to measure telomeres in birds, but with limitations. TRF analysis is time consuming, while relative qPCR gives a within‐study relative value making it difficult to compare across experiments. Utilising an approach first developed in humans of using synthetic oligomer telomeric (TTAGGG)n and normaliser gene standards of known length to calibrate qPCR values, we describe a methodological adaptation to the avian qPCR telomere assay to make results comparable within, and potentially between, bird species. We evaluate this absolute qPCR method in the Seychelles warbler Acrocephalus sechellensis against relative qPCR measurements on the same samples. Telomere estimates from both methods showed an age‐related decline in telomere length, and were highly correlated (r = 0.99). Absolute qPCR avian telomere analysis may prove a useful means of estimating telomere lengths in a calibrated, sensitive, and efficient way using small amounts of archived bird sample. 相似文献
883.
884.
Determination of volatile products of human colon cell line metabolism by GC/MS analysis 总被引:2,自引:0,他引:2
Dunja Zimmermann Michelle Hartmann Mary Pat Moyer Jürgen Nolte Jörg Ingo Baumbach 《Metabolomics : Official journal of the Metabolomic Society》2007,3(1):13-17
Colon cancer is one of the most reasons for cancer death worldwide. Thus, it is important to find new prognostic and diagnostic
marker, as well as to throw light on the special metabolic pathways of colon cancer cells. This paper highlights for the first
time some qualitative differences in the profiles of the volatile metabolites of colon cancer cell lines SW 480 (grade IV,
Duke B) and SW 1116 (grade II, Duke A) among themselves and in comparison to the normal colon cell line NCM460, which are
mostly represented by ketones and alcohols. These results, which were obtained by applying solid phase micro extraction (SPME)
and combined gas chromatography/mass spectrometry (GC/MS), are consistent with Warburg’s hypothesis because the found reaction
products may indicate that the cancer cells show the Crabtree’s effect. Furthermore, compounds like undecan-2-ol and pentadecan-2-one
were associated for the first time with the human metabolism. In summary, these findings indicate that the metabolism of colon
cancer cells differs extremely from the metabolism of healthy cells and it changes during the progress of the disease. Compounds
that are present in the breath, the blood and the tissue of patients represent the differences and they can serve as new biomarker
for colon cancer in future. 相似文献
885.
886.
M J Concannon 《Plastic and reconstructive surgery》1992,90(6):1124-1125
887.
Sam P. D. Lalljie Johan Vindevogel Gopal Murugan Henri J. Dumont Pat Sandra 《Hydrobiologia》1996,319(2):103-109
We identified and quantified the major inorganic ions present in a haemolymph of four species of fairy shrimp, to determine its ionic strength, using capillary electrophoresis, non-destructive micro-technique for the analysis of small amounts of body fluids. This is the first speciation and quantitative analysis of inorganic ions in the haemolymph of fairy shrimps. 相似文献