76
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Barrett JA, Evans L, Chappell J, Fraser C, Clayton L. Bobath or Motor Relearning Programme: a continuing debate. Clin Rehabil 2001; 15:445-6. [PMID: 11518446 DOI: 10.1191/026921501678310252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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77
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Abstract
Sea level change during the Quaternary is primarily a consequence of the cyclic growth and decay of ice sheets, resulting in a complex spatial and temporal pattern. Observations of this variability provide constraints on the timing, rates, and magnitudes of the changes in ice mass during a glacial cycle, as well as more limited information on the distribution of ice between the major ice sheets at any time. Observations of glacially induced sea level changes also provide information on the response of the mantle to surface loading on time scales of 10(3) to 10(5) years. Regional analyses indicate that the earth-response function is depth dependent as well as spatially variable. Comprehensive models of sea level change enable the migration of coastlines to be predicted during glacial cycles, including the anthropologically important period from about 60,000 to 20,000 years ago.
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78
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Tudhope AW, Chilcott CP, McCulloch MT, Cook ER, Chappell J, Ellam RM, Lea DW, Lough JM, Shimmield GB. Variability in the El Niño-Southern Oscillation through a glacial-interglacial cycle. Science 2001; 291:1511-7. [PMID: 11222850 DOI: 10.1126/science.1057969] [Citation(s) in RCA: 730] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The El Niño-Southern Oscillation (ENSO) is the most potent source of interannual climate variability. Uncertainty surrounding the impact of greenhouse warming on ENSO strength and frequency has stimulated efforts to develop a better understanding of the sensitivity of ENSO to climate change. Here we use annually banded corals from Papua New Guinea to show that ENSO has existed for the past 130,000 years, operating even during "glacial" times of substantially reduced regional and global temperature and changed solar forcing. However, we also find that during the 20th century ENSO has been strong compared with ENSO of previous cool (glacial) and warm (interglacial) times. The observed pattern of change in amplitude may be due to the combined effects of ENSO dampening during cool glacial conditions and ENSO forcing by precessional orbital variations.
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79
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Chappell J, Golovchenko I, Wall K, Stjernholm R, Leitner JW, Goalstone M, Draznin B. Potentiation of Rho-A-mediated lysophosphatidic acid activity by hyperinsulinemia. J Biol Chem 2000; 275:31792-7. [PMID: 10930411 DOI: 10.1074/jbc.m004798200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have shown previously that insulin promotes phosphorylation and activation of farnesyltransferase and geranylgeranyltransferase (GGTase) II. We have now examined the effect of insulin on geranylgeranyltransferase I in MCF-7 breast cancer cells. Insulin increased GGTase I activity 3-fold and augmented the amounts of geranylgeranylated Rho-A by 18%. Both effects of the insulin were blocked by an inhibitor of GGTase I, GGTI-286. The insulin-induced increases in the amounts of geranylgeranylated Rho-A resulted in potentiation of the Rho-A-mediated effects of lysophosphatidic acid (LPA) on a serum response element-luciferase construct. Preincubation of cells with insulin augmented the LPA-stimulated serum response element-luciferase activation to 12-fold, compared with just 6-fold for LPA alone (p < 0.05). The potentiating effect of insulin was dose-dependent, inhibited by GGTI-286 and not mimicked by insulin-like growth factor-1. We conclude that insulin activates GGTase I, increases the amounts of geranylgeranylated Rho-A protein, and potentiates the Rho-A-dependent nuclear effects of LPA in MCF-7 breast cancer cells.
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80
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Mandujano-Chávez A, Schoenbeck MA, Ralston LF, Lozoya-Gloria E, Chappell J. Differential induction of sesquiterpene metabolism in tobacco cell suspension cultures by methyl jasmonate and fungal elicitor. Arch Biochem Biophys 2000; 381:285-94. [PMID: 11032417 DOI: 10.1006/abbi.2000.1961] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Jasmonates are well documented for their ability to modulate the expression of plant genes and to influence specific aspects of disease/pest resistance traits. We and others have been studying the synthesis of sesquiterpene phytoalexins in elicitor/pathogen-challenged plants and have sought to determine if methyl jasmonate (MeJA) could substitute for fungal elicitors in the induction of capsidiol accumulation by tobacco cell cultures. The current results demonstrate that MeJA does in fact induce phytoalexin accumulation, but with a much more delayed induction time course than elicitor. While elicitor treatment induced strong but transient changes in key enzymes of sesquiterpene biosynthesis, sesquiterpene cyclase, and aristolochene/deoxy-capsidiol hydroxylase, MeJA did not. Instead, MeJA caused a protracted induction of cyclase activity and only a low level of hydroxylase activity. MeJA induced the expression of at least two sesquiterpene cyclase genes, including one that had not been observed previously in elicitor-induced mRNA populations. Only a small portion of the total sesquiterpene cyclase mRNA induced by MeJA was associated with polysomal RNA, suggesting that the MeJA treatment imposed both transcriptional and posttranscriptional regulation in tobacco cells. These results are not consistent with MeJA playing a role in orchestrating defense responses in elicitor-treated tobacco cells, but do provide evidence that MeJA induces a subset of genes coding for the biosynthesis of sesquiterpene phytoalexins.
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MESH Headings
- Acetates/pharmacology
- Amino Acid Sequence
- Base Sequence
- Carbon-Carbon Lyases/genetics
- Cells, Cultured
- Cellulase/pharmacology
- Cyclopentanes/pharmacology
- DNA Primers/genetics
- DNA, Plant/genetics
- Fungal Proteins/pharmacology
- Gene Expression Regulation, Enzymologic/drug effects
- Gene Expression Regulation, Plant/drug effects
- Genes, Plant
- Molecular Sequence Data
- Oxylipins
- Plant Growth Regulators/pharmacology
- Plants, Toxic
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Homology, Amino Acid
- Sequence Homology, Nucleic Acid
- Sesquiterpenes/metabolism
- Nicotiana/drug effects
- Nicotiana/genetics
- Nicotiana/metabolism
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81
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Abstract
Wandering spleen is an uncommon entity in childhood and has been described only rarely in association with gastric volvulus. Wandering spleen and gastric volvulus were diagnosed in a 5-year-old boy who presented with acute abdominal pain and distension. Intraoperatively, normal ligamentous connections between the stomach, spleen, and posterior abdominal wall were absent. Developmental anomalies that result in wandering spleen may lead to hypermobility of the stomach and a predisposition to gastric volvulus. In such patients, prophylactic gastropexy should be considered.
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82
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Okada S, Devarenne TP, Chappell J. Molecular characterization of squalene synthase from the green microalga Botryococcus braunii, race B. Arch Biochem Biophys 2000; 373:307-17. [PMID: 10620354 DOI: 10.1006/abbi.1999.1568] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The green microalga Botryococcus braunii produces large amounts of liquid hydrocarbons and is classified into three races, depending on the type of the hydrocarbon produced. The B race produces two types of triterpenoid hydrocarbons, squalene and botryococcene, both of which are putative condensation products of farnesyl diphosphate. In an attempt to better understand the regulation involved in the production of squalene and botryococcene, we have isolated and characterized a squalene synthase (SS) gene from the B race of B. braunii. A 366-bp cDNA fragment was initially obtained from the B race utilizing a reverse transcription/polymerase chain reaction and degenerate primers based on conserved amino acid sequences found in all SS enzymes. Using this putative SS fragment as a probe, a 2632-bp cDNA clone was isolated from a cDNA library. This cDNA contained an open reading frame coding for a protein with 461 amino acids and a predicted molecular mass of 52.5 kDa. Comparison of the Botryococcus SS (BSS) with SS from different organisms showed 52% identity with Nicotiana tabacum, 51% with Arabidopsis thaliana, 48% with Zea mays, 40% with rat, 39% with yeast, and 26% with Zymomonas mobilis. Expression of full-length and carboxy-terminus truncated BSS cDNA in Escherichia coli resulted in significant levels of bacterial SS enzyme activity but no botryococcene synthase activity. RNA blot hybridization analysis of algal cultures during a culture cycle indicated that BSS gene expression is preferential during rapid growth. Given that the DNA blot analysis indicated only a single copy of the SS gene in the algal genome, these results suggest either that there exists coordinate expression of separate synthase genes for squalene and botryococcene biosynthesis or that there might be unique physiological conditions controlling the SS vs botryococcene synthase activity of a single peptide species.
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83
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Sarnthein M, Kennett JP, Chappell J, Crowley T, Curry W, Dupessy JC, Grootes P, Hendy I, Laj C, Negendank J, Schulz M, Shackleton NJ, Voelker A, Zolitschka B. Exploring Late Pleistocene climate variations. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/eo081i051p00625-01] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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84
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list: performing large numbers of prostate surgeries is associated with better outcomes and can lead to shorter hospital stays. J Natl Cancer Inst 1999; 91:1905A. [PMID: 10564665 DOI: 10.1093/jnci/91.22.1905a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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85
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list: african-americans with colon cancer fare better in clinical trials than in the general population. J Natl Cancer Inst 1999; 91:1905B. [PMID: 10564666 DOI: 10.1093/jnci/91.22.1905b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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86
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Thai L, Rush JS, Maul JE, Devarenne T, Rodgers DL, Chappell J, Waechter CJ. Farnesol is utilized for isoprenoid biosynthesis in plant cells via farnesyl pyrophosphate formed by successive monophosphorylation reactions. Proc Natl Acad Sci U S A 1999; 96:13080-5. [PMID: 10557276 PMCID: PMC23903 DOI: 10.1073/pnas.96.23.13080] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/1999] [Indexed: 11/18/2022] Open
Abstract
The ability of Nicotiana tabacum cell cultures to utilize farnesol (F-OH) for sterol and sesquiterpene biosynthesis was investigated. [(3)H]F-OH was readily incorporated into sterols by rapidly growing cell cultures. However, the incorporation rate into sterols was reduced by greater than 70% in elicitor-treated cell cultures whereas a substantial proportion of the radioactivity was redirected into capsidiol, an extracellular sesquiterpene phytoalexin. The incorporation of [(3)H]F-OH into sterols was inhibited by squalestatin 1, suggesting that [(3)H]F-OH was incorporated via farnesyl pyrophosphate (F-P-P). Consistent with this possibility, N. tabacum proteins were metabolically labeled with [(3)H]F-OH or [(3)H]geranylgeraniol ([(3)H]GG-OH). Kinase activities converting F-OH to farnesyl monophosphate (F-P) and, subsequently, F-P-P were demonstrated directly by in vitro enzymatic studies. [(3)H]F-P and [(3)H]F-P-P were synthesized when exogenous [(3)H]F-OH was incubated with microsomal fractions and CTP. The kinetics of formation suggested a precursor-product relationship between [(3)H]F-P and [(3)H]F-P-P. In agreement with this kinetic pattern of labeling, [(32)P]F-P and [(32)P]F-P-P were synthesized when microsomal fractions were incubated with F-OH and F-P, respectively, with [gamma-(32)P]CTP serving as the phosphoryl donor. Under similar conditions, the microsomal fractions catalyzed the enzymatic conversion of [(3)H]GG-OH to [(3)H]geranylgeranyl monophosphate and [(3)H]geranylgeranyl pyrophosphate ([(3)H]GG-P-P) in CTP-dependent reactions. A novel biosynthetic mechanism involving two successive monophosphorylation reactions was supported by the observation that [(3)H]CTP was formed when microsomes were incubated with [(3)H]CDP and either F-P-P or GG-P-P, but not F-P. These results document the presence of at least two CTP-mediated kinases that provide a mechanism for the utilization of F-OH and GG-OH for the biosynthesis of isoprenoid lipids and protein isoprenylation.
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87
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list: few physicians counsel adolescents about smoking. J Natl Cancer Inst 1999; 91:1789B. [PMID: 10547377 DOI: 10.1093/jnci/91.21.1789b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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88
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list: new information helps women decide about taking tamoxifen to prevent breast cancer. J Natl Cancer Inst 1999; 91:1789A. [PMID: 10547376 DOI: 10.1093/jnci/91.21.1789a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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89
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list : A viral gene may Be involved in the rapid growth of Kaposi's sarcoma lesions. J Natl Cancer Inst 1999; 91:1703A. [PMID: 10528010 DOI: 10.1093/jnci/91.20.1703a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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90
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list : high blood levels of vitamin E associated with lower incidence of lung cancer. J Natl Cancer Inst 1999; 91:1703B. [PMID: 10528011 DOI: 10.1093/jnci/91.20.1703b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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91
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list. J Natl Cancer Inst 1999; 91:1599A. [PMID: 10511579 DOI: 10.1093/jnci/91.19.1599a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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92
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list. J Natl Cancer Inst 1999; 91:1525A. [PMID: 10491419 DOI: 10.1093/jnci/91.18.1525a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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93
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Chappell J, Eckstein D. MEMORANDUM FOR: Science Writers and Editors on the Journal Press List. J Natl Cancer Inst 1999; 91:1437A. [PMID: 10469736 DOI: 10.1093/jnci/91.17.1437a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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94
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list. J Natl Cancer Inst 1999; 91:1347A. [PMID: 10451430 DOI: 10.1093/jnci/91.16.1347a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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95
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Abstract
It seems reasonable to assume that pigeons use visual features in the landscape for orientation when they are homing over familiar terrain. Experimental evidence to prove or disprove this possibility is, however, difficult to obtain. Here, we link the problem with the observation that deflections of initial orientation caused by clock-shift are often smaller than predicted on a pure sun compass basis. We substantiate the hypothesis that consistently reduced deflections and increased angular scatter occur only when pigeons are released in familiar areas where a remembered pattern of landscape features can conflict with the position of the sun. Repeated releases of the same individuals under clock-shift, or elimination of non-visual navigational clues (odours), appear to strengthen the conflicting influence of familiar visual landmarks. Accelerated returns of birds allowed to preview the surrounding familiar scenery before release also support the conclusion that the visual environment is included in the homing system of pigeons. The landscape, however, not only helps home-finding, if it is familiar, but may also have a distracting influence that contributes to the great variability of initial orientation patterns.
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96
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list. J Natl Cancer Inst 1999; 91:1263A. [PMID: 10433606 DOI: 10.1093/jnci/91.15.1263a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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97
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list. J Natl Cancer Inst 1999; 91:1177A-177. [PMID: 10413406 DOI: 10.1093/jnci/91.14.1177a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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98
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Chappell J, Eckstein D. MEMORANDUM FOR: science writers and editors on the journal press list. J Natl Cancer Inst 1999; 91:1093AA-1093A. [PMID: 10393707 DOI: 10.1093/jnci/91.13.1093aa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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99
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Chappell J, Eckstein D. MEMORANDUM FOR: Science Writers and Editors on the Journal Press List. J Natl Cancer Inst 1999. [DOI: 10.1093/jnci/91.12.987aa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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100
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Chappell J, Eckstein D. MEMORANDUM FOR: Science Writers and Editors on the Journal Press List. J Natl Cancer Inst 1999. [DOI: 10.1093/jnci/91.11.899a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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