ライフサイエンスコーパス: carbon-14

1 ted for assessing absorption and kinetics of carbon-14 ((14)C)-labeled substances after oral ingestio

2 continuous label offered by the radiocarbon (carbon-14, (14) C) bomb spike to estimate the mean age o

3 The carbon-14 (14C) content of methane (14CH4) should distin

4 ble fraction of the increase of the ratio of carbon-14 (14C) to carbon in the atmosphere and surface

5 me P450 3A4 activity was estimated using the carbon-14 [14C]erythromycin breath test (ERMBT) before s

6 was determined from the specific activity of carbon-14 [14C]lactate in aortic blood during a constant

7 situ in a stream with high dissolved organic carbon (14.6 mg/L).

8 Using natural-abundance carbon-14 analysis of membrane lipids, we show that 74 t

9 production rates of the cosmogenic nuclides carbon-14 and beryllium-10 and centennial to millennial

10 in records of cosmogenic nuclide production (carbon-14 and beryllium-10) that is thought to reflect v

11 Carbon-14 and published beryllium-10 data together sugge

12 Reconstructed changes in atmospheric carbon-14 are larger than previously thought, with the l

13 d calibrated carbon-14 years before present (carbon-14 assays).

14 e were up to 50% higher than is suggested by carbon-14 calibration data.

15 epancy could be explained by addition of low-carbon-14 carbon dioxide to the atmosphere during that p

16 onclusions based on the distributions of the carbon-14/carbon ratio and a quasi-conservative property

17 together suggest that concurrent climate and carbon-14 changes were predominantly the result of abrup

18 linear response up to 387 times contemporary carbon-14 concentrations.

19 Analyses of their carbon-14 content by accelerator mass spectrometry (AMS)

20 n delta13C between -22 and -33 per mil and a carbon-14 content that is 40 to 60 percent of that of mo

21 ve delta13C of +32 to +40 per mil with a low carbon-14 content, consistent with an extraterrestrial o

22 Radiocarbon (carbon-14) data from the Aegean Bronze Age 1700-1400 B.C

23 summit of Sajama mountain in Bolivia provide carbon-14-dated tropical records and extend to the Late

24 By using carbon-14 dates from the surrounding region, cultural ph

25 We show, using histological and carbon-14 dating approaches, that in adult humans new ne

26 By carbon-14 dating of dissolved organic carbon (which make

27 e, we exposed mycorrhizal plants to fossil ("carbon-14-dead") carbon dioxide and collected samples of

28 onstrated by comparing pharmacokinetics from carbon-14 dosed guinea pigs analyzed by both CRDS and ac

29 The system was characterized using carbon-14 elevated glucose samples and returned a linear

30 Carbon-14 free and contemporary carbon-14 samples with v

31 these cultures derives from assimilation of carbon-14-free organic carbon from the shale.

32 and discussed, and the capability to measure carbon-14 in biological samples is demonstrated by compa

33 ture, robust hardware for the measurement of carbon-14 in biological studies.

34 by retrospective cell birth dating measuring carbon-14 in genomic DNA.

35 Carbon-14 is an important tool in understanding patterns

36 viable, as determined by the respiration of carbon-14-labeled acetate and glucose substrates during

37 ion (13) or extension of the linker to three carbons (14) led to enhanced thiol stability and the pre

38 imit of approximately one-third contemporary carbon-14 levels.

39 Carbon-14 measurements on 231 elephant ivory specimens f

40 loped a convergent synthetic route to an all-carbon, 14-membered Z,E-macrocyclic bis-enone during our

41 Carbon-14 free and contemporary carbon-14 samples with varying carbon-13 concentrations

42 r heparin-induced thrombocytopenia using the carbon-14 serotonin-release assay as the reference metho

43 se-granule secretion (assessed by release of carbon 14-serotonin) was almost completely inhibited by

44 the Cariaco Basin provide calibration of the carbon-14 time scale across the period of deglaciation (

45 ch presented affords easy access to powerful carbon-14 tracer techniques that can characterize comple

46 phaera profunda centered on a period of 7600 carbon-14 years (8400 calendar years) are present in hig

47 he present ( approximately 12,310 and 12,290 carbon-14 years ago).

48 between 8.20 and 12.67 thousand calibrated carbon-14 years before present (carbon-14 assays).

49 cultural lifeway at 3.6 thousand calibrated carbon-14 years before present.

50 contexts dated to approximately 3120 to 3020 carbon-14 years before the present ( approximately 1410

51 Holocene and then rose abruptly around 6300 carbon-14 years before the present (14C yr B.P.).

52 The burial dates to 3776 to 3690 carbon-14 years before the present (2155 to 1936 calenda

53 Terminal Pleistocene (about 11,100 to 10,000 carbon-14 years before the present or about 13,000 to 11

54 d years before the present (10,770 to 10,530 carbon-14 years before the present).

55 y during the Late Pleistocene, before 12,400 carbon-14 years before the present.

56 o deep ocean sites, and it is 2400 to 13,900 carbon-14 years older than non-BC SOC deposited concurre