The rise of COVID-19 cases is associated with support for world leaders.

abstract：:Von Willebrand factor-binding protein (VWbp), secreted by Staphylococcus aureus, displays secondary structural homology to the 3-helix bundle, D1 and D2 domains of staphylocoagulase (SC), a potent conformational activator of the blood coagulation zymogen, prothrombin (ProT). In contrast to the classical proteolytic ac...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kroh HK,Panizzi P,Bock PE

更新日期：2009-05-12 00:00:00

abstract：:A climate/vegetation model simulates episodic wetter and drier periods at the 21,000-y precession period in eastern North Africa, the Arabian Peninsula, and the Levant over the past 140,000 y. Large orbitally forced wet/dry extremes occur during interglacial time, ∼130 to 80 ka, and conditions between these two extrem...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kutzbach JE,Guan J,He F,Cohen AS,Orland IJ,Chen G

更新日期：2020-02-04 00:00:00

abstract：:By harnessing the oxidative power of microorganisms, energy can be recovered from reservoirs of less-concentrated organic matter, such as marine sediment, wastewater, and waste biomass. Left unmanaged, these reservoirs can become eutrophic dead zones and sites of greenhouse gas generation. Here, we introduce a unique ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Xie X,Ye M,Hsu PC,Liu N,Criddle CS,Cui Y

更新日期：2013-10-01 00:00:00

abstract：:New neurons are generated in adult mammalians and may contribute to repairing the brain after injury. Here, we show that the number of new neurons in the dentate gyrus of adult rats increased in cerebral ischemic stroke and correlated with activation of the cAMP-response-element-binding protein (CREB). Inhibition of e...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zhu DY,Lau L,Liu SH,Wei JS,Lu YM

更新日期：2004-06-22 00:00:00

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 ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Vermeij GJ

更新日期：1973-07-01 00:00:00

abstract：:Activity-dependent means of altering calcium (Ca(2)(+)) influx are assumed to be of great physiological consequence, although definitive tests of this assumption have only begun to emerge. Facilitation and inactivation offer two opposing, activity-dependent means of altering Ca(2+) influx via cardiac Ca(v)1.2 calcium ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Blaich A,Welling A,Fischer S,Wegener JW,Köstner K,Hofmann F,Moosmang S

更新日期：2010-06-01 00:00:00

abstract：:Two photochromic activators of the electrogenic membrane of the electroplax of Electrophorus electricus are described. Trans-3,3'-bis[alpha-(trimethylammonium)methyl]azobenzene dibromide (Bis-Q), one of the most potent ever reported, is active at concentrations of less than 10(-7) M. Its cis isomer, which is obtained ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bartels E,Wassermann NH,Erlanger BF

更新日期：1971-08-01 00:00:00

abstract：:A series of hairpin pyrrole-imidazole polyamide-fluorescein conjugates were synthesized and assayed for cellular localization. Thirteen cell lines, representing 11 human cancers, one human transformed kidney cell line, and one murine leukemia cell line, were treated with 5 microM polyamide-fluorescein conjugates for 1...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Best TP,Edelson BS,Nickols NG,Dervan PB

更新日期：2003-10-14 00:00:00

abstract：:Illumination of a system consisting of a vertical tube containing an unstirred homogeneous suspension of thylakoids in an imposed linear concentration gradient of an electron acceptor, 2,6-dichloroindophenol, gave rise to a one-dimensional banded pattern of the acceptor that evolved in a time-dependent manner. The spa...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Aon M,Thomas D,Hervagault JF

更新日期：1989-01-01 00:00:00

abstract：:Plant germ cells develop in specialized haploid structures, termed gametophytes. The female gametophyte patterns of flowering plants are diverse, with often unknown adaptive value. Here we present the Arabidopsis fiona mutant, which forms a female gametophyte that is structurally and functionally reminiscent of a phyl...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kägi C,Baumann N,Nielsen N,Stierhof YD,Gross-Hardt R

更新日期：2010-12-21 00:00:00

abstract：:Incorporation and conversion of icosapentaenoic acid (20:5, n - 3) by human polymorphonuclear leukocytes were studied in volunteers (n = 6) ingesting a normal Western diet supplemented with icosapentaenoic acid (approximately equal to 4 g daily). Ingestion of icosapentaenoic acid leads to formation of biologically les...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Strasser T,Fischer S,Weber PC

更新日期：1985-03-01 00:00:00

abstract：:The planarity of peptide bonds is an assumption that underlies decades of theoretical modeling of proteins. Peptide bonds strongly deviating from planarity are considered very rare features of protein structure that occur for functional reasons. Here, empirical analyses of atomic-resolution protein structures reveal t...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Berkholz DS,Driggers CM,Shapovalov MV,Dunbrack RL Jr,Karplus PA

更新日期：2012-01-10 00:00:00

abstract：:Malignant spreading of cancer cells requires cell surface proteases that cleave the crosslinked collagenous matrix of connective tissues. From correlating the morphologically defined invasiveness of tumor cells with the presence of specific membrane-associated proteases, we have identified a malignant human melanoma c...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Aoyama A,Chen WT

更新日期：1990-11-01 00:00:00

abstract：:Phonoangiography, the quantitative analysis of sounds produced by blood flow, has been used to investigate local fluid motion in arteries narrowed by atherosclerosis. The sound spectra measured in vivo were found to be identical to those obtained in laboratory investigations of turbulent pipe flow. A theoretical model...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Lees RS,Dewey CF Jr

更新日期：1970-10-01 00:00:00

abstract：:In this paper is presented the theory of a class of locally convex lattices (L-lattices) of real functions which generalize the classical Lebesgue spaces. The monotone and dominated convergence theorems for convergence almost everywhere and sequential and order completeness of such lattices are established. These resu...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bogdanowicz WM

更新日期：1970-06-01 00:00:00

abstract：:Nearly 500 alkaloids have been detected in skin extracts from frogs of the family Dendrobatidae. All seem to have been sequestered unchanged into skin glands from alkaloid-containing arthropods. Ants, beetles, and millipedes seem to be the source of decahydroquinolines, certain izidines, coccinellines, and spiropyrrol...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Daly JW,Kaneko T,Wilham J,Garraffo HM,Spande TF,Espinosa A,Donnelly MA

更新日期：2002-10-29 00:00:00

abstract：:Netrin-1 is critical for axonal pathfinding which shares similarities with formation of vascular network. Here we report that netrin-1 induction of angiogenesis is mediated by an increase in endothelial nitric oxide (NO*) production, which occurs via a DCC-dependent, ERK1/2-eNOS feed-forward mechanism. Exposure of mat...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Nguyen A,Cai H

更新日期：2006-04-25 00:00:00

abstract：:The biosynthesis of rebeccamycin, an antitumor compound, involves the remarkable eight-electron oxidation of chlorinated chromopyrrolic acid. Although one rebeccamycin biosynthetic enzyme is capable of generating low levels of the eight-electron oxidation product on its own, a second protein, RebC, is required to acce...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ryan KS,Howard-Jones AR,Hamill MJ,Elliott SJ,Walsh CT,Drennan CL

更新日期：2007-09-25 00:00:00

abstract：:The mammalian hair follicle unit consists of a central follicle and a series of associated structures: sebaceous glands, arrector pili muscles, Merkel cells, and sensory nerve endings. The architecture of this multicellular structure is highly polarized with respect to the body axes. Previous work has implicated Frizz...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chang H,Nathans J

更新日期：2013-03-05 00:00:00

abstract：:We constructed a comprehensive cDNA library from HeLa cell mRNA in a vector that directs expression of the cDNA in Saccharomyces cerevisiae. We used this library to clone the human counterpart of the Sa. cerevisiae CCAAT-binding transcription factor, Hap2, by functional complementation of a hap2 mutation. The cDNA enc...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Becker DM,Fikes JD,Guarente L

更新日期：1991-03-01 00:00:00

abstract：:The impact of ligand binding on nuclear receptor (NR) structure and the ability of target cells to distinguish between different receptor-ligand complexes are key determinants of the pharmacological activity of NR ligands. However, until relatively recently, these mechanistic insights have not been used in a prospecti...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Joseph JD,Wittmann BM,Dwyer MA,Cui H,Dye DA,McDonnell DP,Norris JD

更新日期：2009-07-21 00:00:00

abstract：:The regulatory mechanisms that use signals of low levels of reactive oxygen species (ROS) could be obscured by ROS produced under stress and thus are better investigated under homeostatic conditions. Previous studies showed that the chloroplastic atypical thioredoxin ACHT1 is oxidized by 2-Cys peroxiredoxin (2-Cys Prx...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Eliyahu E,Rog I,Inbal D,Danon A

更新日期：2015-10-13 00:00:00

abstract：:Pyrroline-carboxy-lysine (Pcl) is a demethylated form of pyrrolysine that is generated by the pyrrolysine biosynthetic enzymes when the growth media is supplemented with D-ornithine. Pcl is readily incorporated by the unmodified pyrrolysyl-tRNA/tRNA synthetase pair into proteins expressed in Escherichia coli and in ma...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ou W,Uno T,Chiu HP,Grünewald J,Cellitti SE,Crossgrove T,Hao X,Fan Q,Quinn LL,Patterson P,Okach L,Jones DH,Lesley SA,Brock A,Geierstanger BH

更新日期：2011-06-28 00:00:00

abstract：:Lysinuric protein intolerance (LPI) is an autosomal recessive phenotype consistent with impaired transport of cationic amino acids at the basolateral membrane of intestinal and renal epithelia. On the assumption that the basolateral membrane of epithelial cells and plasma membrane of parenchymal cells are functional a...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Smith DW,Scriver CR,Tenenhouse HS,Simell O

更新日期：1987-11-01 00:00:00

abstract：:Plasmodium vivax uses a single member of the Duffy binding-like (DBL) receptor family to invade erythrocytes and is not found in West Africa where its erythrocyte ligand, the Duffy blood group antigen, is missing. In contrast, Plasmodium falciparum expresses four members of the DBL family, and remarkably, single-point...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Mayer DC,Jiang L,Achur RN,Kakizaki I,Gowda DC,Miller LH

更新日期：2006-02-14 00:00:00

abstract：:Galectin-3 is a glycan-binding protein (GBP) that binds β-galactoside glycan structures to orchestrate a variety of important biological events, including the activation of hepatic stellate cells and regulation of immune responses. While the requisite glycan epitopes needed to bind galectin-3 have long been elucidated...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Joeh E,O'Leary T,Li W,Hawkins R,Hung JR,Parker CG,Huang ML

更新日期：2020-11-03 00:00:00

abstract：:Hypnotic analgesia in some respects resembles opiate analgesia. We tested the hypothesis that some features of hypnotic analgesia are mediated through neuronal pathways activating specific opiate receptors in brain. The opiate antagonist naloxone had no effect on hypnotic analgesia in three subjects. Thus, the hypothe...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Goldstein A,Hilgard ER

更新日期：1975-06-01 00:00:00

abstract：:Double immunofluorescent labeling experiments for lysosomes and either microtubules or vimentin intermediate filaments in cultured well-spread fibroblasts show a remarkable degree of superposition of the lysosomes and the microtubules. Under two different sets of conditions where the microtubules and intermediate fila...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Collot M,Louvard D,Singer SJ

更新日期：1984-02-01 00:00:00

abstract：:The origin-binding protein (OBP) from herpes simplex virus 1 is a member of the SF2 helicase superfamily and is required for the initiation of DNA synthesis from a viral origin of DNA replication (oriS). The high-affinity binding sites for OBP in oriS, boxes I and II, are separated by an A+T-rich spacer. We used the g...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gustafsson CM,Hammarsten O,Falkenberg M,Elias P

更新日期：1994-05-24 00:00:00

abstract：:The Sleeping Beauty (SB) transposon system can integrate foreign sequences of DNA in the genome of mouse somatic cells eliciting long-term expression in vivo. This technology holds great promise for human gene therapy as a nonviral technology to deliver therapeutic genes. SB also provides a means to study the effects ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Carlson CM,Frandsen JL,Kirchhof N,McIvor RS,Largaespada DA

更新日期：2005-11-22 00:00:00