Abstract:
:Electron spectroscopic imaging, a new technique that permits the quantitative detection of the spatial distributions of atomic elements at high resolution, has been applied to the epiphyseal zone of hypertrophy in the mouse for the visualization of calcium, phosphorus, and sulfur. Longitudinally sectioned epiphyseal growth plates reveal a developmental sequence in the longitudinal septum leading from a noncalcified matrix to a calcified matrix. During the early stages of this transition, matrix granules containing highly localized concentrations of P (200-400 atoms/nm2) are found spatially separate from Ca-containing sites. These Ca localizations displayed a concentration range of 20-350 atoms/nm2 and a complete spatial overlap with sulfur. At these sites, S levels range from 10 to 200 atoms/nm2. At a later stage, and therefore more proximal to the zone of provisional calcification, the usual scattered, irregularly shaped mineral deposits are found. These sites contain a virtual superposition of Ca with both P and S. The Ca/P and Ca/S ratios of these mineral deposits are predominantly 1.0 with only minor, locally varying ratios present.
journal_name
Proc Natl Acad Sci U S Aauthors
Arsenault AL,Ottensmeyer FPdoi
10.1073/pnas.80.5.1322subject
Has Abstractpub_date
1983-03-01 00:00:00pages
1322-6issue
5eissn
0027-8424issn
1091-6490journal_volume
80pub_type
杂志文章abstract::The influential role of Wnt5a in tumor progression underscores the requirement for developing molecules that can target Wnt5a-mediated cellular responses. In the aggressive skin cancer, melanoma, elevated Wnt5a expression promotes cell motility and drives metastasis. Two approaches can be used to counteract these effe...
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.0909409106
更新日期:2009-11-17 00:00:00
abstract::Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors are an established treatment in estrogen receptor-positive breast cancer and are currently in clinical development in melanoma, a tumor that exhibits high rates of CDK4 activation. We analyzed melanoma cells with acquired resistance to the CDK4/6 inhibitor palbociclib an...
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.1901323116
更新日期:2019-09-03 00:00:00
abstract::Myelodysplastic syndromes (MDS) are among the most frequent hematologic malignancies. Patients have a short survival and often progress to acute myeloid leukemia. The diagnosis of MDS can be difficult; there is a paucity of molecular markers, and the pathophysiology is largely unknown. Therefore, we conducted a multic...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,多中心研究
doi:10.1073/pnas.0610330104
更新日期:2007-01-23 00:00:00
abstract::Direct conversion of carbon dioxide to multicarbon products remains as a grand challenge in electrochemical CO2 reduction. Various forms of oxidized copper have been demonstrated as electrocatalysts that still require large overpotentials. Here, we show that an ensemble of Cu nanoparticles (NPs) enables selective form...
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.1711493114
更新日期:2017-10-03 00:00:00
abstract::beta1,4-Galactosyltransferase (beta4GalT-I) participates in both glycoconjugate biosynthesis (ubiquitous activity) and lactose biosynthesis (mammary gland-specific activity). In somatic tissues, transcription of the mammalian beta4GalT-I gene results in a 4.1-kb mRNA and a 3.9-kb mRNA as a consequence of initiation at...
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.95.25.14805
更新日期:1998-12-08 00:00:00
abstract::Evidence is presented for two natural transcription initiators positioned internally in the histidine operon of Salmonella typhimurium. They were detected using highly polar S. typhimurium his mutants as recipients for F' Escherichia coli his episomes. These intergeneric complementation tests provide a sensitive metho...
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.65.4.925
更新日期:1970-04-01 00:00:00
abstract::To study the structure and function of the gene for parathyroid hormone, we obtained recombinant plasmids containing bovine parathyroid hormone cDNA. The nucleotide sequence at the 5' terminus (relative to the sense strand) of the cDNA insert in a recombinant plasmid, pPTHi4, was different from that previously reporte...
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.78.7.4073
更新日期:1981-07-01 00:00:00
abstract::Single-nucleotide polymorphisms (SNPs) in the human ether-a-go-go-related gene 1, hERG1, are associated with cardiac arrhythmias. The Kv11.1 channels encoded by hERG1 are also essential for rhythmic excitability of the pituitary, where they are regulated by thyroid hormone through a signal transduction cascade involvi...
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.0802250105
更新日期:2008-09-23 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.1019490108
更新日期:2011-07-05 00:00:00
abstract::Protective immunity against human schistosome infection develops slowly, for reasons that are not yet fully understood. For many decades, researchers have attempted to infer properties of the immune response from epidemiological studies, with mathematical models frequently being used to bridge the gap between immunolo...
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.1121051109
更新日期:2012-08-14 00:00:00
abstract::The callipyge mutation (CLPG) is an A to G transition that affects a muscle-specific long-range control element located in the middle of the 90-kb DLK1-GTL2 intergenic (IG) region. It causes ectopic expression of a 327-kb cluster of imprinted genes in skeletal muscle, resulting in the callipyge muscular hypertrophy an...
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.0602844103
更新日期:2006-05-23 00:00:00
abstract::Sublethal insults can induce tolerance to subsequent stressors in neurons. As cell death activators such as ROS generation and decreased ATP can initiate tolerance, we tested whether other cellular elements normally associated with neuronal injury could add to this process. In an in vivo model of ischemic tolerance, w...
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.0232966100
更新日期:2003-01-21 00:00:00
abstract::Hyperpolarization of substrates for magnetic resonance spectroscopy (MRS) and imaging (MRI) by dissolution dynamic nuclear polarization (D-DNP) usually involves saturating the ESR transitions of polarizing agents (PAs; e.g., persistent radicals embedded in frozen glassy matrices). This approach has shown enormous pote...
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.1407730111
更新日期:2014-10-14 00:00:00
abstract::During mammalian aging, cellular proteins become increasingly damaged: for example, by carbonylation and formation of advanced glycation end products (AGEs). The means to ensure that offspring are born without such damage are unknown. Unexpectedly, we found that undifferentiated mouse ES cells contain high levels of b...
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.0510944103
更新日期:2006-05-16 00:00:00
abstract::The cytosolic concentration of free Ca2+ in bovine neutrophils was monitored by using the intracellular Ca2+ indicator quin2, 2-[[2-bis(acetylamino)-5-methylphenoxy]methyl-6-methoxy-8- bis(acetylamino)]quinoline. Neutrophils at rest have a cytosolic Ca2+ concentration of 85 +/- 5 nM, which in 2-4 min increases to 300-...
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.81.5.1416
更新日期:1984-03-01 00:00:00
abstract::Blood cells transplantation is largely replacing bone marrow transplantation because engraftment is more rapid. This accelerated engraftment is thought to be mediated by relatively mature committed hematopoietic progenitor cells. Herein, we have used a modified rhodamine (Rho) staining procedure to identify and purify...
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.95.2.725
更新日期:1998-01-20 00:00:00
abstract::Incubation of physiological concentrations of 125I-labeled insulin with liver membranes in the presence of anti-insulin IgG results in a 7- to 15-fold increase in the specific binding of the hormone. The low-affinity/high-capacity binding sites are replaced by an apparently homogeneous class of high-affinity sites, an...
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.76.6.2720
更新日期:1979-06-01 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:2013-04-16 00:00:00
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更新日期:2019-07-30 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.2019265118
更新日期:2021-01-05 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:2020-11-10 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:2011-09-27 00:00:00
abstract::We have analyzed the spectra of UV-induced mutations in the lacI gene of a wild-type and an mfd strain of Escherichia coli. mfd strains have been recently proposed to be deficient in a factor coupling DNA repair and transcription. Analysis of UV-induced mutations occurring at adjacent pyrimidines showed that mutations...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1992-11-15 00:00:00
abstract::The release of urine, or micturition, serves a fundamental physiological function and, in many species, is critical for social communication. In mice, the pattern of urine release is modulated by external and internal factors and transmitted to the spinal cord via the pontine micturition center (PMC). Here, we exploit...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2021-01-05 00:00:00
abstract::Native cytochrome c (cyt c) has a compact tertiary structure with a hexacoordinated heme iron and functions in electron transport in mitochondria and apoptosis in the cytoplasm. However, the possibility that protein modifications confer additional functions to cyt c has not been explored. Disruption of methionine 80 (...
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:2009-02-24 00:00:00
abstract::Stress-induced structural remodeling in the adult hippocampus, involving debranching and shortening of dendrites and suppression of neurogenesis, provides a cellular basis for understanding the impairment of neural plasticity in the human hippocampus in depressive illness. Accordingly, reversal of structural remodelin...
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.211427898
更新日期:2001-10-23 00:00:00
abstract::Noonan syndrome (NS) is a relatively common genetic disorder, characterized by typical facies, short stature, developmental delay, and cardiac abnormalities. Known causative genes account for 70-80% of clinically diagnosed NS patients, but the genetic basis for the remaining 20-30% of cases is unknown. We performed ne...
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:2014-08-05 00:00:00
abstract::To elucidate the molecular mechanism of frameshift suppression by the SUF2 gene of yeast, the sequences of DNA fragments carrying the SUF2-1 and suf2+ alleles of the gene and surrounding regions have been determined. Comparison of the suppressor and wild-type sequences indicates that the SUF2 gene product is a proline...
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.79.11.3565
更新日期:1982-06-01 00:00:00