Abstract:
:Examples from various plant and animal groups indicate that there has been a general increase in potential versatility of form, determined by the number and range of independently varying morphogenetic parameters, among taxa appearing at successively younger stages in the fossil record. Taxa or body plans with higher potential versatility have tended to replace less potentially versatile groups in the same or similar adaptive zone through time. Greater potential diversity allows for greater homeostasis, efficiency, and integration of structures and functions, and for an increase in size of the potential adaptive zone. In contrast, chemical versatility has generally decreased within groups from the pre-Cambrian to the Phanerozoic, partly as the result of apparent changes in the chemical environment and partly as the consequence of selection for efficiency and greater metabolic ease of handling of certain materials.
journal_name
Proc Natl Acad Sci U S Aauthors
Vermeij GJdoi
10.1073/pnas.70.7.1936subject
Has Abstractpub_date
1973-07-01 00:00:00pages
1936-8issue
7eissn
0027-8424issn
1091-6490journal_volume
70pub_type
杂志文章abstract::Replication of HIV-1 and N-tropic murine leukemia virus (N-MLV) is restricted in a number of different primate cells. In some cell lines, cross-saturation experiments suggest that the two viruses are interacting with the same restriction factor. Recently, Trim5alpha protein from rhesus monkey was found to restrict HIV...
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.0402876101
更新日期:2004-07-20 00:00:00
abstract::Ciliary neurotrophic factor (CNTF) receptor controls a pathway supporting the differentiation and survival of a wide range of neural cell types during development and in adulthood. Cardiotrophin-like cytokine (CLC)-cytokine-like factor 1 (CLF) composite cytokine is a second ligand for the CNTF alpha-component receptor...
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.0509598103
更新日期:2006-06-27 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.1612017113
更新日期:2016-11-08 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.92.23.10713
更新日期:1995-11-07 00:00:00
abstract::Rod-like colloids distort fluid interfaces and interact by capillarity. We explore this interaction at the free surface of aligned nematic liquid crystal films. Naive comparison of capillary and elastic energies suggests that particle assembly would be determined solely by surface tension. Here, we demonstrate that, u...
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.1504817112
更新日期:2015-05-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.12.7487
更新日期:1981-12-01 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
doi:10.1073/pnas.1211761110
更新日期:2013-01-02 00:00:00
abstract::A direct method for the determination of N-linked glycosylation sites in highly glycosylated proteins is described. Carcinoembryonic antigen (CEA) and a nonspecific crossreacting antigen (NCA) were chemically deglycosylated, and peptide maps were prepared by reverse-phase HPLC. The peptides were sequenced on a gas-pha...
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.84.4.920
更新日期:1987-02-01 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
doi:10.1073/pnas.1013054108
更新日期:2011-03-29 00:00:00
abstract::The tissue-specific transcriptional coactivator OCA-B is required for antigen-dependent B cell differentiation events, including germinal center formation. However, the identity of OCA-B target genes involved in this process is unknown. This study has used large-scale cDNA arrays to monitor changes in gene expression ...
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.1033108100
更新日期:2003-07-22 00:00:00
abstract::We report on the location of the chain part of the retinylidene chromophore in the projected density of bacteriorhodopsin as determined by neutron diffraction from the two-dimensional purple membrane lattice. For this purpose, partially deuterated retinal was synthesized containing 10 deuterons at positions C-8, C-10,...
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.82.10.3227
更新日期:1985-05-01 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
doi:10.1073/pnas.0611222104
更新日期:2007-04-10 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
doi:10.1073/pnas.1612362113
更新日期:2016-10-18 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.86.13.5118
更新日期:1989-07-01 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
doi:10.1073/pnas.75.4.2044
更新日期:1978-04-01 00:00:00
abstract::Aberrant transcription of the pericentromeric human satellite II (HSATII) repeat is present in a wide variety of epithelial cancers. In deriving experimental systems to study its deregulation, we observed that HSATII expression is induced in colon cancer cells cultured as xenografts or under nonadherent conditions 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.1518008112
更新日期:2015-12-08 00:00:00
abstract::A particularly promising approach to deconstructing and fractionating lignocellulosic biomass to produce green renewable fuels and high-value chemicals pretreats the biomass with organic solvents in aqueous solution. Here, neutron scattering and molecular-dynamics simulations reveal the temperature-dependent morpholog...
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.1922883117
更新日期:2020-07-21 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.0600161103
更新日期:2006-05-16 00:00:00
abstract::Purified preparations of rabbit skeletal white, red, and cardiac muscle myosin (WM, RM, and CM) were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Significant differences in both the molecular weights and number of light chains in these myosins were found. WM has three distinct light-chain co...
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:1971-05-01 00:00:00
abstract::Hepatitis B virus (HBV) is a major human pathogen. In addition to its importance in human health, there is growing interest in adapting HBV and other viruses for drug delivery and other nanotechnological applications. In both contexts, precise biophysical characterization of these large macromolecular particles is fun...
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.0800406105
更新日期:2008-07-08 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.0910280107
更新日期:2010-01-05 00:00:00
abstract::Ecological "surprises" are defined as unexpected findings about the natural environment. They are critically important in ecology because they are catalysts for questioning and reformulating views of the natural world, help shape assessments of the veracity of a priori predictions about ecological trends and phenomena...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.1015696107
更新日期:2010-12-21 00:00:00
abstract::Spin-polarized charge currents induce magnetic tunnel junction (MTJ) switching by virtue of spin-transfer torque (STT). Recently, by taking advantage of the spin-dependent thermoelectric properties of magnetic materials, novel means of generating spin currents from temperature gradients, and their associated thermal-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.1507084112
更新日期:2015-05-26 00:00:00
abstract::Adenosine-to-inosine (A-to-I) RNA editing, catalyzed by ADAR enzymes, is a ubiquitous mechanism that generates transcriptomic diversity. This process is particularly important for proper neuronal function; however, little is known about how RNA editing is dynamically regulated between the many functionally distinct ne...
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.1811768116
更新日期:2019-02-05 00:00:00
abstract::An evolutionary framework for viewing the formation, the stability, the organizational structure, and the social dynamics of biological families is developed. This framework is based upon three conceptual pillars: ecological constraints theory, inclusive fitness theory, and reproductive skew theory. I offer a set of 1...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.92.18.8092
更新日期:1995-08-29 00:00:00
abstract::A photoreactive derivative of epidermal growth factor (EGF) has been used to identify and specifically label a membrane receptor for EGF on mouse 3T3 cells. Photoactivable EGF, labeled with 125I, was incubated with 3T3 cells and then photolyzed in situ to generate a nitrene capable of reacting with a wide variety of c...
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.74.7.2790
更新日期:1977-07-01 00:00:00
abstract::Metabolic crossfeeding is an important process that can broadly shape microbial communities. However, little is known about specific crossfeeding principles that drive the formation and maintenance of individuals within a mixed population. Here, we devised a series of synthetic syntrophic communities to probe the comp...
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.1405641111
更新日期:2014-05-20 00:00:00
abstract::Strong, short-ranged positional correlations involving counterions can induce a net attractive force between negatively charged strands of DNA and lead to the formation of ion pairs in dilute ionic solutions. However, the long range of the Coulomb interactions impedes the development of a simple local picture. We addr...
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.0600282103
更新日期:2006-05-16 00:00:00
abstract::CR1 is a short interspersed repetitive DNA element originally identified in the domestic chicken (Gallus gallus). However, unlike virtually all other such sequences described to date, CR1 is not confined to one or a few closely related species. It is probably a ubiquitous component of the avian genome, having been det...
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.88.13.5814
更新日期:1991-07-01 00:00:00
abstract::Arabidopsis has been popular as a model plant system for decades. Completion of the Arabidopsis genome and the availability of large expressed sequence-tag collections from other dicot species provides an opportunity to assess gene content in Arabidopsis, specifically by identifying genes from dicot test species that ...
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.142126599
更新日期:2002-07-09 00:00:00