Abstract:
:It is suggested that differentiated embryonic cells have a high specificity of molecular constitution as regards the surface layers surrounding their cellular membranes. Correspondingly, specific interface energies may characterize the early contacts between different cell types. The question is raised whether the morphology of the developing embryo may be understood in terms of cellular arrangements which minimize the total interface energy. Bilateral symmetry prevalent in early embryonic development of higher animals might be understood on the basis of the adoption of such a minimum energy principle if, in addition, one assumes that embryonic development is uniquely determined for a particular species.
journal_name
Proc Natl Acad Sci U S Aauthors
Jehle Hdoi
10.1073/pnas.67.1.156subject
Has Abstractpub_date
1970-09-01 00:00:00pages
156-63issue
1eissn
0027-8424issn
1091-6490journal_volume
67pub_type
杂志文章abstract::A stable complex between pentaammineruthenium(III) and histidine-33 in horse heart ferricytochrome c is formed in the reaction between aquopentaammineruthenium(II) and the protein at pH 7. HPLC of the tryptic hydrolysate of the modified protein was employed to identify the pentaammineruthenium binding site. Spectrosco...
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.79.22.7052
更新日期:1982-11-01 00:00:00
abstract::The oscillator of the circadian clock of cyanobacteria is composed of three proteins, KaiA, KaiB, and KaiC, which together generate a self-sustained ∼24-h rhythm of phosphorylation of KaiC. The mechanism propelling this oscillator has remained elusive, however. We show that stacking interactions between the CI and CII...
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.1211508109
更新日期:2012-10-16 00:00:00
abstract::Neutrophils are immune cells that bind to, engulf, and destroy bacterial and fungal pathogens in infected tissue, and their clearance by apoptosis is essential for the resolution of inflammation. Killing involves both oxidative and nonoxidative processes, the oxidative pathway requiring electrogenic production of supe...
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.0607914103
更新日期:2006-11-14 00:00:00
abstract::The S-M checkpoint delays mitosis until DNA replication is complete; cells defective in this checkpoint lose viability when DNA replication is inhibited. This inviability can be suppressed in fission yeast by overexpression of Cid1 or the related protein Cid13. Fission yeast contain six cid1/cid13-like genes, whereas ...
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.192467799
更新日期:2002-09-17 00:00:00
abstract::Muscle contraction and relaxation is regulated by transient elevations of myoplasmic Ca(2+). Ca(2+) is released from stores in the lumen of the sarco(endo)plasmic reticulum (SER) to initiate formation of the Ca(2+) transient by activation of a class of Ca(2+) release channels referred to as ryanodine receptors (RyRs) ...
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.0905186106
更新日期:2009-07-07 00:00:00
abstract::In the prostate gland of adult mammals, most epithelial cells are in a state of proliferative quiescence. Androgens regulate this effect by inducing cell cycle arrest in the G(0)/G(1) phase. Potential mediators of this androgen-induced proliferative shutoff were identified by means of subtracted cDNA libraries. The ex...
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.97.18.10185
更新日期:2000-08-29 00:00:00
abstract::Studies on the structure-function relationship of diphtheria toxin are reported. New methods are described for the preparation of pure intact ("unnicked") toxin and for the preparation of the individual A and B chains. A biological assay method for the B chain is also presented, as well as a method for the labelling o...
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.74.2.472
更新日期:1977-02-01 00:00:00
abstract::Unlike other predators that use vision as their primary sensory system, bats compute the three-dimensional (3D) position of flying insects from discrete echo snapshots, which raises questions about the strategies they employ to track and intercept erratically moving prey from interrupted sensory information. Here, we ...
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.2011719117
更新日期:2020-11-17 00:00:00
abstract::Ancient societies are often used to illustrate the potential problems stemming from unsustainable land-use practices because the past seems rife with examples of sociopolitical "collapse" associated with the exhaustion of finite resources. Just as frequently, and typically in response to such presentations, archaeolog...
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
doi:10.1073/pnas.1409646111
更新日期:2014-08-12 00:00:00
abstract::Amphibians are a bellwether for environmental degradation, even in natural ecosystems such as Yellowstone National Park in the western United States, where species have been actively protected longer than anywhere else on Earth. We document that recent climatic warming and resultant wetland desiccation are causing sev...
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.0809090105
更新日期:2008-11-04 00:00:00
abstract::Communication about prescription drugs ought to be a paragon of public science communication. Unfortunately, it is not. Consumers see $4 billion of direct-to-consumer advertising annually, which typically fails to present data about how well drugs work. The professional label--the Food and Drug Administration's (FDA) ...
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.1214646110
更新日期:2013-08-20 00:00:00
abstract::Even in the absence of sensory stimulation, the neocortex shows complex spontaneous activity patterns, often consisting of alternating "DOWN" states of generalized neural silence and "UP" states of massive, persistent network activity. To investigate how this spontaneous activity propagates through neuronal assemblies...
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.0605643104
更新日期:2007-01-02 00:00:00
abstract::Axonal degeneration is an initial key step in traumatic and neurodegenerative CNS disorders. We established a unique in vivo epifluorescence imaging paradigm to characterize very early events in axonal degeneration in the rat optic nerve. Single retinal ganglion cell axons were visualized by AAV-mediated expression of...
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.0909794107
更新日期:2010-03-30 00:00:00
abstract::Germ-line mutations of tumor suppressor genes confer strong predisposition to tumor formation. In the rat, a form of dominantly inherited renal carcinoma (RC) results in multiple chromophobe cell tumors that resemble the human disease, and heterozygous carriers (RC/+) are highly susceptible to environmental agents (ra...
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.90.17.8038
更新日期:1993-09-01 00:00:00
abstract::Autism spectrum disorder (ASD) is characterized by impaired social interactions and communication. The pathogenesis of ASD is not known, but it involves activation of microglia. We had shown that the peptide neurotensin (NT) is increased in the serum of children with ASD and stimulates cultured adult human microglia t...
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.2004666117
更新日期:2020-07-14 00:00:00
abstract::Humans are consciously aware of some memories and can make verbal reports about these memories. Other memories cannot be brought to consciousness, even though they influence behavior. This conspicuous difference in access to memories is central in taxonomies of human memory systems but has been difficult to document i...
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.071600998
更新日期:2001-04-24 00:00:00
abstract::Leptin is a pivotal regulator of energy and glucose homeostasis, and defects in leptin signaling result in obesity and diabetes. The ATP-sensitive potassium (K(ATP)) channels couple glucose metabolism to insulin secretion in pancreatic β-cells. In this study, we provide evidence that leptin modulates pancreatic β-cell...
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.1216351110
更新日期:2013-07-30 00:00:00
abstract::The transcription factor interferon regulatory factor 5 (IRF5) is essential for the induction of inflammatory cytokines, but the mechanism by which IRF5 is activated is not well understood. Here we present evidence that the kinase IKKβ phosphorylates and activates IRF5 in response to stimulation in several inflammator...
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.1418516111
更新日期:2014-12-09 00:00:00
abstract::A 3- to 5-year cycle of vole abundances is a characteristic phenomenon in the ecology of northern regions, and their explanation stands as a central theoretical challenge in population ecology. Although many species of voles usually coexist and are in severe competition for food and breeding space, the role of intersp...
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.96.3.986
更新日期:1999-02-02 00:00:00
abstract::alpha-Amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-type glutamate receptors undergo constitutive and ligand-induced internalization that requires dynamin and the clathrin adaptor complex AP-2. We report here that an atypical basic motif within the cytoplasmic tails of AMPA-type glutamate receptors directl...
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.0611170104
更新日期:2007-02-20 00:00:00
abstract::Infection of BALB/3T3 cells by polyoma virus causes an alteration in the cell surface, characterized by enhanced agglutination of the cells by wheat germ agglutinin or concanavalin A. Infection by the thermosensitive mutant of polyoma, ts-3, causes the cell surface alteration at the permissive temperature, but not 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.68.2.283
更新日期:1971-02-01 00:00:00
abstract::Dense granules of platelets contain a high content of diadenosine 5',5'''-P1,P4-tetraphosphate (Ap4A). We have previously demonstrated an antithrombotic effect of this compound in a live rabbit model. In the present study we find that certain synthetic Ap4A analogues are superior to Ap4A in inhibiting ADP-induced aggr...
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.89.6.2370
更新日期:1992-03-15 00:00:00
abstract::By optically probing with a focused, low-power laser beam, we measured the spontaneous deflection fluctuations of the sensory hair bundles on frog saccular hair cells with a sensitivity of about 1 pm/square root of Hz. The preparation was illuminated by two orthogonally polarized laser beams separated by only about 0....
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.86.14.5371
更新日期:1989-07-01 00:00:00
abstract::We applied the directional tag PCR subtractive hybridization method to construct a rat hypothalamic cDNA library from which cerebellar and hippocampal sequences had been depleted, enriching 20-30-fold for sequences expressed selectively in the hypothalamus. We studied a sample of 94 clones selected for enrichment in t...
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.93.16.8733
更新日期:1996-08-06 00:00:00
abstract::All cell functions that involve membrane deformation or a change in cell shape (e.g., endocytosis, exocytosis, cell motility, and cytokinesis) are regulated by membrane tension. While molecular contacts between the plasma membrane and the underlying actin cytoskeleton are known to make significant contributions to mem...
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.0901641106
更新日期:2009-07-21 00:00:00
abstract::A gene's expression pattern provides clues to its role in normal physiology and disease. To provide quantitative expression levels on a genome-wide scale, the Cancer Genome Anatomy Project (CGAP) uses serial analysis of gene expression (SAGE). Over 5 million transcript tags from more than 100 human cell types have bee...
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.152324199
更新日期:2002-08-20 00:00:00
abstract::Recently it has become apparent that N = 2 supersymmetric quantum field theory has something to do with cluster algebras. I review one aspect of the connection: supersymmetric quantum field theories have associated hyperkähler moduli spaces, and these moduli spaces carry a structure that looks like an extension of the...
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.1313073111
更新日期:2014-07-08 00:00:00
abstract::Regulation of adult stem cells (SCs) is fundamental for organ maintenance and tissue regeneration. On the body surface, different ectodermal organs exhibit distinctive modes of regeneration and the dynamics of their SC homeostasis remain to be unraveled. A slow cycling characteristic has been used to identify SCs in 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.1318848111
更新日期:2014-10-21 00:00:00
abstract::γ-Secretase is an intramembrane-cleaving protease responsible for the generation of amyloid-β (Aβ) peptides. Recently, a series of compounds called γ-secretase modulators (GSMs) has been shown to decrease the levels of long toxic Aβ species (i.e., Aβ42), with a concomitant elevation of the production of shorter Aβ spe...
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.1402171111
更新日期:2014-07-22 00:00:00
abstract::Understanding biological and physical processes involving nucleic acids, such as the binding of proteins to DNA and RNA, DNA condensation, and RNA folding, requires an understanding of the ion atmosphere that surrounds nucleic acids. We have used a simple model DNA system to determine how the ion atmosphere modulates ...
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.0404448102
更新日期:2005-01-25 00:00:00