Abstract:
:The growth or decay of population of a single species interacting with a large number of other species (or environment) according to the Volterra-Lotka model is investigated. When the environment is initially very close to its equilibrium level, the growth of a single species follows a generalized Verhulst law, containing hereditary effects. The derivation, modeled on statistical mechanical theories of Brownian motion, leads also to a "noise" source and to its relation to the heredity kernel. A special case, where the hereditary kernel is a damped exponential function of time, is solved numerically. When growth starts at a level much below equilibrium, the population first overshoots equilibrium and then approaches it. When decay starts at a level much higher than equilibrium, the population first decays precipitously to a very low level and then slowly grows toward equilibrium.
journal_name
Proc Natl Acad Sci U S Aauthors
Zwanzig Rdoi
10.1073/pnas.70.11.3048subject
Has Abstractpub_date
1973-11-01 00:00:00pages
3048-51issue
11eissn
0027-8424issn
1091-6490journal_volume
70pub_type
杂志文章abstract::Ler, a homolog of H-NS in enteropathogenic Escherichia coli (EPEC), plays a critical role in the expression of virulence genes encoded by the pathogenic island, locus of enterocyte effacement (LEE). Although Ler acts as an antisilencer of multiple LEE operons by alleviating H-NS-mediated silencing, it represses its ow...
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.1322033111
更新日期:2014-06-24 00:00:00
abstract::Alzheimer's disease (AD), characterized by cognitive decline, has emerged as a disease of synaptic failure. The present study reveals an unanticipated role of erythropoietin-producing hepatocellular A4 (EphA4) in mediating hippocampal synaptic dysfunctions in AD and demonstrates that blockade of the ligand-binding dom...
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.1405803111
更新日期:2014-07-08 00:00:00
abstract::Fibrodysplasia ossificans progressiva (FOP) patients carry a missense mutation in ACVR1 [617G > A (R206H)] that leads to hyperactivation of BMP-SMAD signaling. Contrary to a previous study, here we show that FOP fibroblasts showed an increased efficiency of induced pluripotent stem cell (iPSC) generation. This positiv...
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.1603668113
更新日期:2016-11-15 00:00:00
abstract::Clear-cut inherited Mendelian traits, such as familial adenomatous polyposis or hereditary nonpolyposis colorectal cancer, account for <4% of colorectal cancers. Another 20% of all colorectal cancers are thought to occur in individuals with a significant inherited multifactorial susceptibility to colorectal cancer 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.0407187101
更新日期:2004-11-09 00:00:00
abstract::Although major research efforts have focused on how specific components of foodstuffs affect health, relatively little is known about a more fundamental aspect of diet, the frequency and circadian timing of meals, and potential benefits of intermittent periods with no or very low energy intakes. The most common eating...
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.1413965111
更新日期:2014-11-25 00:00:00
abstract::In this report we identify the specific isozymes of protein kinase C (PKC) that are involved in c-fos and c-jun mRNA accumulation in the rat basophilic leukemia cell line RBL-2H3. These cells could be largely depleted of the endogenous PKC isozymes by chronic treatment with phorbol 12-myristate 13-acetate followed by ...
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.91.16.7722
更新日期:1994-08-02 00:00:00
abstract::The class of neurons within the visual cortex of normal adult cats that has the smallest receptive fields (less than or equal to 2.25 degrees2) and that responds only to low rates of stimulus motion (less than or equal to 50 degrees / sec) responds preferentially to lines oriented about either the horizontal axis (+/-...
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.74.3.1272
更新日期:1977-03-01 00:00:00
abstract::The defining feature of the mycobacterial outer membrane (OM) is the presence of mycolic acids (MAs), which, in part, render the bilayer extremely hydrophobic and impermeable to external insults, including many antibiotics. Although the biosynthetic pathway of MAs is well studied, the mechanism(s) by which these lipid...
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.1700062114
更新日期:2017-07-25 00:00:00
abstract::Homologous recombination is an important biological process that occurs in all organisms and facilitates genome rearrangements and repair of DNA double-strand breaks. Eukaryotic Rad51 proteins (Rad51sp or Rhp51 in fission yeast) are functional and structural homologs of bacterial RecA protein, an evolutionarily conser...
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.2632890100
更新日期:2003-12-23 00:00:00
abstract::Copper is an essential micronutrient that plays a central role for a broad range of biological processes. Although there is compelling evidence that the intracellular milieu does not contain any free copper ions, the rapid kinetics of copper uptake and release suggests the presence of a labile intracellular copper poo...
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.0406547102
更新日期:2005-08-09 00:00:00
abstract::Although antibodies to HLA play a role in the pathogenesis of diseases processes such as rejection of transplanted organs, the precise mechanisms by which antibodies cause tissue injury are not completely understood. We hypothesized that antibodies to host tissues cause inflammation in part by activating endothelial e...
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.0602035104
更新日期:2007-01-23 00:00:00
abstract::Insertion of the transposon Tn5 into the T-region of the octopine Ti plasmid of Agrobacterium tumefaciens gives rise to crown gall tumors having altered morphology. Three loci within the T-DNA that control tumor morphology have been detected [Garfinkel, D. J., Simpson, R. B., Ream, L. W., White, F. F., Gordon, M. 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.80.2.407
更新日期:1983-01-01 00:00:00
abstract::Natural-abundance (13)C nuclear magnetic resonance spectra of ten common nucleotides in neutral, aqueous solutions have been determined and interpreted. The spectra of two of these substances were also determined in acidic solutions, and several of the carbon chemical shifts were found to depend markedly on pH. Within...
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.65.1.19
更新日期:1970-01-01 00:00:00
abstract::Nogo isoforms (Nogo-A and -B) have been implicated in regulating neural and cardiovascular functions, such as cell spreading and chemotaxis. Unlike the loop domain (Nogo-66) found in all Nogo isoforms that can interact with a neural-specific Nogo-66 receptor, the receptor for the amino terminus of Nogo-B that mediates...
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.0602427103
更新日期:2006-07-18 00:00:00
abstract::The regulation of glycogen metabolism is critical for the maintenance of glucose and energy homeostasis in mammals. Glycogen synthase, the enzyme responsible for glycogen production, is regulated by multisite phosphorylation in yeast and mammals. We have previously identified PAS kinase as a physiological regulator 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.0508481102
更新日期:2005-11-15 00:00:00
abstract::Sustained activity of mammalian methionine synthase (MS) requires MS reductase (MSR), but there have been few studies of the interactions between these two proteins. In this study, recombinant human MS (hMS) and MSR (hMSR) were expressed in baculovirus-infected insect cells and purified to homogeneity. hMSR maintained...
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.0603694103
更新日期:2006-06-20 00:00:00
abstract::Primary HIV-1 isolates were evaluated for their sensitivity to inhibition by beta-chemokines RANTES (regulated upon activation, normal T-cell expressed and secreted), macrophage inflammatory protein 1 alpha (MIP-1 alpha), and MIP-1 beta. Virus isolates of both nonsyncytium-inducing (NSI) and syncytium-inducing (SI) bi...
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.93.26.15382
更新日期:1996-12-24 00:00:00
abstract::The calcium, calmodulin-dependent phosphatase calcineurin, regulates growth and gene expression of striated muscles. The activity of calcineurin is modulated by a family of cofactors, referred to as modulatory calcineurin-interacting proteins (MCIPs). In the heart, the MCIP1 gene is activated by calcineurin and has be...
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.0308723101
更新日期:2004-03-02 00:00:00
abstract::We have previously shown that chronic activation of mitogenic signaling induced by over-expression of c-myc and transforming growth factor-alpha (TGFalpha) transgenes in mouse liver induces a state of oxidative stress. We therefore proposed that increased reactive oxygen species (ROS) generation might be responsible f...
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.040428797
更新日期:2000-02-29 00:00:00
abstract::The Mars Organic Analyzer (MOA), a microfabricated capillary electrophoresis (CE) instrument for sensitive amino acid biomarker analysis, has been developed and evaluated. The microdevice consists of a four-wafer sandwich combining glass CE separation channels, microfabricated pneumatic membrane valves and pumps, and ...
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.0406798102
更新日期:2005-01-25 00:00:00
abstract::The self-adjoint algebra of operators generated by the semigroup of translation operators acting on the Hilbert space of functions supported on the half-line is studied. A real-valued index is introduced and is used to determine the spectrum of the Wiener-Hopf integral operators with distribution kernel having an almo...
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.62.4.1010
更新日期:1969-04-01 00:00:00
abstract::The polypeptide composition of the phycobilisome, the major light-harvesting complex of prokaryotic cyanobacteria and certain eukaryotic algae, can be modulated by different light qualities in cyanobacteria exhibiting chromatic adaptation. We have identified genomic fragments encoding a cluster of phycobilisome polype...
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.83.11.3924
更新日期:1986-06-01 00:00:00
abstract::In confluent fibroblast monolayers, an increase in the selective uptake of free cholesterol (FC) from plasma low density lipoprotein (LDL) was accompanied by an increase in FC efflux. The rate of FC efflux was proportional to the FC content of the cell surface caveolae and to mRNA levels of caveolin, an FC-binding pro...
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.94.8.3753
更新日期:1997-04-15 00:00:00
abstract::Calcific aortic valve disease is a chronic inflammatory process, and aortic valve interstitial cells (AVICs) from diseased aortic valves express greater levels of osteogenic factors in response to proinflammatory stimulation. Here, we report that lower cellular levels of IL-37 in AVICs of diseased human aortic valves ...
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.1619667114
更新日期:2017-02-14 00:00:00
abstract::Theoretical and experimental optical, redox, and paramagnetic results are presented for models of siroheme, the iron isobacteriochlorin prosthetic group of nitrite and sulfite reductases, and of sirohydrochlorin, the metal-free siroheme that is an intermediate in the biosynthetic pathway to vitamin B(12). The facile 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.78.5.2652
更新日期:1981-05-01 00:00:00
abstract::The p53 tumor-suppressor protein is a critical mediator of cellular growth arrest and the induction of apoptosis. To identify proteins involved in the modulation of p53 transcriptional activity, a gain-of-function cellular screen was carried out with an arrayed matrix of approximately 20,000 cDNAs. Nine genes previous...
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.0308562100
更新日期:2004-03-09 00:00:00
abstract::The interleukin 2 (IL-2) receptor (IL-2R) is a multisubunit receptor that includes three major IL-2 binding subunits, the IL-2R alpha, beta, and gamma chains. We have detected and analyzed cooperative interactions between the IL-2R alpha and beta chains (IL-2R alpha and IL-2R beta, respectively) in COS cells transfect...
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.91.8.3344
更新日期:1994-04-12 00:00:00
abstract::Na(+)-channel inactivation is proposed to occur by binding of an intracellular inactivation gate to a hydrophobic inactivation gate receptor in the intracellular mouth of the pore. Amino acid residues in transmembrane segment S6 of domain IV (IVS6) that are critical for fast inactivation were identified by alanine-sca...
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.91.25.12346
更新日期:1994-12-06 00:00:00
abstract::The three-dimensional structure of a human monoclonal antibody (Fab), which binds specifically to a major epitope of the transmembrane protein gp41 of the human immunodeficiency virus type 1, has been determined by crystallographic methods to a resolution of 2.7 A. It has been previously determined that this antibody ...
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.89.15.7154
更新日期:1992-08-01 00:00:00
abstract::Measles still remains a major cause of childhood morbidity and mortality worldwide. Measles virus (MV) vaccines are highly successful, but the mechanism underlying their efficacy has been unclear. Here we report the crystal structure of the MV attachment protein, hemagglutinin, responsible for MV entry. The receptor-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.0707830104
更新日期:2007-12-04 00:00:00