Abstract:
:The basic assumptions of van der Waals theory are contained in two well-known concepts: excluded volume (repulsive forces) and a homogeneous, isotropic field potential (attractive forces). We have superimposed on these, one more well-known concept: the existence of dimers, trimers, etc., at chemical equilibrium. With reasonable simplifying assumptions, we obtain a closed-form equation of state, applicable to all fluid densities, and potentially useful for fluids containing strongly polar or hydrogen-bonded molecules. At all temperatures and at high densities, the equation of state suggests a phase transition where, because of extensive association, a new (solid-like) phase is in equilibrium with a "normal" fluid phase. The boundary between these phases has no critical point.
journal_name
Proc Natl Acad Sci U S Aauthors
Heidemann RA,Prausnitz JMdoi
10.1073/pnas.73.6.1773subject
Has Abstractpub_date
1976-06-01 00:00:00pages
1773-6issue
6eissn
0027-8424issn
1091-6490journal_volume
73pub_type
杂志文章abstract::The human Thy-1 gene has been isolated and sequenced and compared to the rat and mouse Thy-1 genes. All three genes are organized in the same way: one exon encoding the majority of the signal peptide, another encoding the transmembrane segment, and a third encoding the remainder of the protein. One major structural di...
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.82.19.6657
更新日期:1985-10-01 00:00:00
abstract::Humans routinely formulate plans in domains so complex that even the most powerful computers are taxed. To do so, they seem to avail themselves of many strategies and heuristics that efficiently simplify, approximate, and hierarchically decompose hard tasks into simpler subtasks. Theoretical and cognitive research has...
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.1414219112
更新日期:2015-03-10 00:00:00
abstract::Solar emission produces copious nitrosonium ions (NO(+)) in the D layer of the ionosphere, 60 to 90 km above the Earth's surface. NO(+) is believed to transfer its charge to water clusters in that region, leading to the formation of gaseous nitrous acid (HONO) and protonated water cluster. The dynamics of this reactio...
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.1601651113
更新日期:2016-04-26 00:00:00
abstract::Recent research on rainforest speciation has highlighted the importance of habitat variation in generating population diversification but lacks evidence of an associated reduction in gene flow. This paper describes a study in which molecular markers were used to examine the effects of allopatric divergence and habitat...
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.212248499
更新日期:2002-10-15 00:00:00
abstract::The translocation from chromosome 8 to chromosome 21, t(8;21), associated with acute myeloid leukemia results in production of an AML1/MTG8(ETO) fusion transcript. The product of the AML1 gene contains an evolutionarily conserved 128-amino acid region referred to as the "Runt domain," which is necessary for binding to...
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.91.24.11723
更新日期:1994-11-22 00:00:00
abstract::Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common blood disorder, presenting multiple symptoms, including hemolytic anemia. It affects 400 million people worldwide, with more than 160 single mutations reported in G6PD. The most severe mutations (about 70) are classified as class I, leading to more...
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.2022790118
更新日期:2021-01-26 00:00:00
abstract::Hitherto it has not been possible to obtain spore and stalk cell differentiation of the cellular slime molds in submerged cultures. It is shown here that cells, when placed in roller tubes under an atmosphere of oxygen, will form clumps and differentiate in 48-72 hr into mature spores and stalk cells. Although differe...
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.74.1.268
更新日期:1977-01-01 00:00:00
abstract::The Pleistocene global dispersal of modern humans required the transit of arid and semiarid regions where the distribution of potable water provided a primary constraint on dispersal pathways. Here, we provide a spatially explicit continental-scale assessment of the opportunities for Pleistocene human occupation of Au...
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.1608470113
更新日期:2016-10-11 00:00:00
abstract::Recombinational repair of double-stranded DNA gaps was investigated in Ustilago maydis. The experimental system was designed for analysis of repair of an autonomously replicating plasmid containing a cloned gene disabled by an internal deletion. It was discovered that crossing over rarely accompanied gap repair. The s...
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.93.11.5419
更新日期:1996-05-28 00:00:00
abstract::To optimize the use of modified adenoviruses as vectors for gene delivery to the myocardium, we have characterized infection of cultured fetal and adult rat cardiac myocytes in vitro and of adult cardiac myocytes in vivo by using a replication-defective adenovirus carrying the chloramphenicol acetyltransferase (CAT) r...
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.90.24.11498
更新日期:1993-12-15 00:00:00
abstract::We describe a 98-base-pair region (-38 to +60) in the long terminal repeat of the Drosophila gypsy retrotransposon that is sufficient for accurate normal-level transcription. We find that, unlike most RNA polymerase II (pol II) promoters, the gypsy promoter includes downstream sequences that are required for full acti...
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.88.1.102
更新日期:1991-01-01 00:00:00
abstract::Purine nucleoside analogs modified by replacement of the nitrogen atom at the 3 position by a CH group give a characteristic circular dichroism curve that is not substantially modified by chemical substitution at the 8 position. Since it is rather well established that 8-substituted purine nucleosides are predominantl...
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.73.7.2384
更新日期:1976-07-01 00:00:00
abstract::Allostery, the coupling between ligand binding and protein conformational change, is the heart of biological network and it has often been explained by two representative models, the induced-fit and the population-shift models. Here, we clarified for what systems one model fits better than the other by performing mole...
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.0802524105
更新日期:2008-08-12 00:00:00
abstract::A retrovirus containing the entire human platelet-derived growth factor B-chain (PDGF-B) gene was constructed in order to investigate the in vivo biological activity of its encoded growth factor. When this virus was introduced into newborn mice, it reproducibly generated fibrosarcomas at the site of inoculation. Provi...
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.86.8.2693
更新日期:1989-04-01 00:00:00
abstract::Chromosome translocations between Ig (Ig) and non-Ig genes are frequently associated with B-cell lymphomas in humans and mice. The best characterized of these is c-myc/IgH translocation, which is associated with Burkitt's lymphoma. These translocations are caused by activation-induced cytidine deaminase (AID), which p...
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.0908946107
更新日期:2010-01-05 00:00:00
abstract::Twice each year, millions of night-migratory songbirds migrate thousands of kilometers. To find their way, they must process and integrate spatiotemporal information from a variety of cues including the Earth's magnetic field and the night-time starry sky. By using sensory-driven gene expression, we discovered that ni...
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.0409575102
更新日期:2005-06-07 00:00:00
abstract::Fungal cell walls and fragments thereof (elicitors) induce the formation of low and high molecular weight defense compounds in plant cell suspension cultures. This induced synthesis requires a signal molecule transmitting the message between the elicitor plant cell wall receptor and gene activation. We demonstrate in ...
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.90.16.7490
更新日期:1993-08-15 00:00:00
abstract::Over the last decade a variety of MS measurements, such as HD exchange, collision cross sections, and electron capture dissociation (ECD), have been used to characterize protein folding in the gas phase, in the absence of solvent. To the extensive data already available on ubiquitin, here photofragmentation of its ECD...
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.212643599
更新日期:2002-12-10 00:00:00
abstract::Loss of miR-15/16 is the most common genetic lesion in chronic lymphocytic leukemia (CLL), promoting overexpression of BCL2, which factors in leukemia pathogenesis. Indeed, an inhibitor of Bcl2, venetoclcax, is highly active in the treatment of patients with CLL. However, single-agent venetoclcax fails to eradicate mi...
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.1708264114
更新日期:2017-10-03 00:00:00
abstract::Virus-specific or group-specific antibody probes to potyviruses can be produced by targeting the immune response to the virus-specific, N-terminal region of the capsid protein (29-95 amino acids depending on the virus) or to the conserved core region (216 amino acids) of the capsid protein, respectively. Immunochemica...
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.86.21.8192
更新日期:1989-11-01 00:00:00
abstract::Gene delivery to skeletal muscle is a promising strategy for the treatment of muscle disorders and for the systemic secretion of therapeutic proteins. However, present DNA delivery technologies have to be improved with regard to both the level of expression and interindividual variability. We report very efficient pla...
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.96.8.4262
更新日期:1999-04-13 00:00:00
abstract::HsPKS1 from Huperzia serrata is a type III polyketide synthase (PKS) with remarkable substrate tolerance and catalytic potential. Here we present the synthesis of unnatural unique polyketide-alkaloid hybrid molecules by exploiting the enzyme reaction using precursor-directed and structure-based approaches. HsPKS1 prod...
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.1107782108
更新日期:2011-08-16 00:00:00
abstract::Antigen receptors on the T-cell surface are noncovalently associated with at least four invariant polypeptide chains, CD3-gamma, -delta, -epsilon, and -zeta. The mouse CD3-gamma gene, consisting of seven exons, was found to be highly homologous to the CD3-delta gene described earlier. Both the high level of sequence h...
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.84.24.9131
更新日期:1987-12-01 00:00:00
abstract::An in vitro system for replication of lambda dv plasmid DNA has been constructed. This system consists of an ammonium sulfate fraction from Escherichia coli extract, exogenously added purified lambda O and P proteins, and lambda dv DNA in closed circular form. More than 85% of the added template DNA replicated semicon...
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.79.24.7639
更新日期:1982-12-01 00:00:00
abstract::Hox genes encode transcription factors widely used for diversifying animal body plans in development and evolution. To achieve functional specificity, Hox proteins associate with PBC class proteins, Pre-B cell leukemia homeobox (Pbx) in vertebrates, and Extradenticle (Exd) in Drosophila, and were thought to use a uniq...
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.1006964108
更新日期:2011-02-08 00:00:00
abstract::Incorporation of 2-acyl spin-labeled lecithin into the phosphatidylcholine protein from bovine liver results in an immobilization of the spin-label at the methyl and the carboxyl terminal end of the acyl chain. The nitroxide group on the protein-bound lecithin molecule is not accessible to ascorbate. This suggests tha...
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.74.5.1807
更新日期:1977-05-01 00:00:00
abstract::The growth of a small number of cells from each of two chemically induced BALB/c sarcomas was enhanced when x-irradiated (15,000 rads) cells of the same sarcoma were mixed with the tumor inoculum. This enhancement did not occur if the recipients had been given a total body x-irradiation of 450 rads. Tumor neutralizati...
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.75.1.436
更新日期:1978-01-01 00:00:00
abstract::A renin promoter-large tumor antigen (T antigen) fusion gene was constructed to provide a reporter function for renin expression in transgenic mice. These transgenic mice gave rise to tumors in subcutaneous soft tissue, which was attributed to transgene expression at this site. An immunohistochemical analysis of trans...
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.87.20.7993
更新日期:1990-10-01 00:00:00
abstract::The preservation of our cultural heritage is of great importance to future generations. Despite this, significant problems have arisen with the conservation of waterlogged wooden artifacts. Three major issues facing conservators are structural instability on drying, biological degradation, and chemical degradation on ...
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.1406037111
更新日期:2014-12-16 00:00:00
abstract::The current study identifies CCR8+ regulatory T cells (Treg cells) as drivers of immunosuppression. We show that in human peripheral blood cells, more than 30% of Treg up-regulate CCR8 following activation in the presence of CCL1. This interaction induces STAT3-dependent up-regulation of FOXp3, CD39, IL-10, and granzy...
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.1621280114
更新日期:2017-06-06 00:00:00