Abstract:
:We have measured the oxygen concentration in the body water of murine FSa and NFSa fibrosarcomas using a new method for quantitative oxygen concentration determination deep in the tissues of a living animal. The measurement uses unusually low-frequency electron paramagnetic spectroscopy sensitive to substrate 7 cm deep in tissue, partially deuterated spin probes (spin labels of molecular mass 195, approximating that of glucose) whose distribution compartment can be targeted with facile adduct substitution, and novel analytic techniques. We show that the water-compartment oxygen concentration of the tumors decreases as the tumor size increases and also shows a trend to decrease as radiobiologic hypoxia increases. An oxymetric spectral image of the tumor is presented. The technique will improve with larger human tissue samples. It provides the potential to quantitatively assess tissue hypoxia in ischemic or preischemic states in stroke and myocardial infarction. It will allow direct assessment of tumor hypoxia to determine the usefulness of radiation and chemotherapy adjuvants directed to hypoxic cell compartments.
journal_name
Proc Natl Acad Sci U S Aauthors
Halpern HJ,Yu C,Peric M,Barth E,Grdina DJ,Teicher BAdoi
10.1073/pnas.91.26.13047subject
Has Abstractpub_date
1994-12-20 00:00:00pages
13047-51issue
26eissn
0027-8424issn
1091-6490journal_volume
91pub_type
杂志文章abstract::We demonstrate remote detection of nuclear magnetic resonance (NMR) with a microchip sensor consisting of a microfluidic channel and a microfabricated vapor cell (the heart of an atomic magnetometer). Detection occurs at zero magnetic field, which allows operation of the magnetometer in the spin-exchange relaxation-fr...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0711505105
更新日期:2008-02-19 00:00:00
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更新日期:2018-08-21 00:00:00
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更新日期:2006-02-07 00:00:00
abstract::Mutant alleles at the dilute unconventional myosin heavy chain locus cause diluted coat color, opisthotonic seizures, and death. The dilute coat color phenotype is caused by irregular clumping of pigment in the hair, but amounts of melanin are unchanged from wild-type controls. The melanocyte phenotype has been descri...
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更新日期:1997-09-16 00:00:00
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更新日期:1986-10-01 00:00:00
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更新日期:1980-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1993-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1998-11-24 00:00:00
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更新日期:2012-08-07 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.84.21.7624
更新日期:1987-11-01 00:00:00
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更新日期:2020-10-20 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1998-06-23 00:00:00
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更新日期:2021-01-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
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更新日期:2010-11-16 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1999-09-14 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2001-09-25 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2011-07-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2004-04-27 00:00:00