Homogeneous catalogs of earthquakes.

abstract：:Commensal and pathogenic bacteria must deal with many different stress conditions to survive in and colonize the human gastrointestinal tract. One major challenge that bacteria encounter in the gut is the high concentration of bile salts, which not only aid in food absorption but also act as effective physiological an...

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

authors： Cremers CM,Knoefler D,Vitvitsky V,Banerjee R,Jakob U

更新日期：2014-04-22 00:00:00

abstract：:Protein-tyrosine kinases (PTKs) are critical enzymes for receptor-mediated signaling in lymphocytes. Because natural killer (NK) cells are large granular lymphocytes with specialized effector function, we set out to identify PTKs preferentially expressed in these cells. One such PTK was identified and molecularly clon...

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

authors： Kawamura M,McVicar DW,Johnston JA,Blake TB,Chen YQ,Lal BK,Lloyd AR,Kelvin DJ,Staples JE,Ortaldo JR

更新日期：1994-07-05 00:00:00

abstract：:The biological function of Glu-181 in the photoactivation process of rhodopsin is explored through spectroscopic studies of site-specific mutants. Preresonance Raman vibrational spectra of the unphotolyzed E181Q mutant are nearly identical to spectra of the native pigment, supporting the view that Glu-181 is uncharged...

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

authors： Yan EC,Kazmi MA,Ganim Z,Hou JM,Pan D,Chang BS,Sakmar TP,Mathies RA

更新日期：2003-08-05 00:00:00

abstract：:We have determined the nucleotide sequence of the dihydrofolate reductase-thymidylate synthetase (DHFR-TS) gene of the protozoan parasite Leishmania major (dihydrofolate reductase, EC 1.5.1.3 and thymidylate synthase, EC 2.1.1.45). The DHFR-TS protein is encoded by a single 1560-base-pair open reading frame within gen...

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

authors： Beverley SM,Ellenberger TE,Cordingley JS

更新日期：1986-04-01 00:00:00

abstract：:Optical waveguides simultaneously transport light at different colors, forming the basis of fiber-optic telecommunication networks that shuttle data in dozens of spectrally separated channels. Here, we reimagine this wavelength division multiplexing (WDM) paradigm in a novel context--the differentiated detection and i...

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

authors： Ozcelik D,Parks JW,Wall TA,Stott MA,Cai H,Parks JW,Hawkins AR,Schmidt H

更新日期：2015-10-20 00:00:00

abstract：:Cyclonic atmospheric vortices of varying intensity, collectively known as low-pressure systems (LPS), travel northwest across central India and produce more than half of the precipitation received by that fertile region and its ∼600 million inhabitants. Yet, future changes in LPS activity are poorly understood, due in...

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

authors： Sandeep S,Ajayamohan RS,Boos WR,Sabin TP,Praveen V

更新日期：2018-03-13 00:00:00

abstract：:Membranes were purified from rat muscle by a differential centrifugation method that avoids the use of salt extraction or incubations at elevated temperature. Three populations of membrane-limited vesicles were defined having average densities of 1.112 (fraction I), 1.141 (fraction II), and 1.158 (fraction III) g/ml i...

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

authors： Barchi RL,Bonilla E,Wong M

更新日期：1977-01-01 00:00:00

abstract：:Poly(ADP ribose) polymerase inhibitors (PARPi) have efficacy in triple negative breast (TNBC) and ovarian cancers (OCs) harboring BRCA mutations, generating homologous recombination deficiencies (HRDs). DNA methyltransferase inhibitors (DNMTi) increase PARP trapping and reprogram the DNA damage response to generate HR...

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

authors： McLaughlin LJ,Stojanovic L,Kogan AA,Rutherford JL,Choi EY,Yen RC,Xia L,Zou Y,Lapidus RG,Baylin SB,Topper MJ,Rassool FV

更新日期：2020-07-28 00:00:00

abstract：:Positive-strand RNA viruses are the largest virus class and include many pathogens such as hepatitis C virus and the severe acute respiratory syndrome coronavirus (SARS). Brome mosaic virus (BMV) is a representative positive-strand RNA virus whose RNA replication, gene expression, and encapsidation have been reproduce...

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

authors： Kushner DB,Lindenbach BD,Grdzelishvili VZ,Noueiry AO,Paul SM,Ahlquist P

更新日期：2003-12-23 00:00:00

abstract：:Terminal oligopyrimidine (TOP) motifs are sequences at the 5' ends of mRNAs that link their translation to the mTOR Complex 1 (mTORC1) nutrient-sensing signaling pathway. They are commonly regarded as discrete elements that reside on ∼100 mRNAs that mostly encode translation factors. However, the full spectrum of TOP ...

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

authors： Philippe L,van den Elzen AMG,Watson MJ,Thoreen CC

更新日期：2020-03-10 00:00:00

abstract：:Argonaute and Piwi proteins are key players in the RNA silencing pathway, with the former interacting with micro-RNAs (miRNAs) and siRNAs, whereas the latter targets piwi-interacting RNAs (piRNAs) that are 2'-O-methylated (2(')-OCH(3)) at their 3' ends. Germline-specific piRNAs and Piwi proteins play a critical role i...

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

authors： Tian Y,Simanshu DK,Ma JB,Patel DJ

更新日期：2011-01-18 00:00:00

abstract：:Mutant Escherichia coli strains in which export of the LamB protein (coded for by the lamB gene) to the outer membrane of the cell is prevented have been described previously. One of these mutant strains contains a small (12-base pair) deletion mutation within the region of the lamB gene that codes for the NH2-termina...

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

authors： Emr SD,Silhavy TJ

更新日期：1983-08-01 00:00:00

abstract：:The saturation values for ribosomal RNA hybridization have been determined for DNA from diploid and polytene tissues of Drosophila melanogaster. These values have been measured in XO and XX larvae which have, respectively, one and two nucleolus organizers in the diploid chromosome set. The results show that (1) in dip...

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

authors： Spear BB,Gall JG

更新日期：1973-05-01 00:00:00

abstract：:The functional capacities of CD8(+) T cells important for virus clearance are influenced by interactions with antigen presenting cells (APCs) and CD4(+) T cells during initial selection, subsequent expansion, and development of memory. Recently, investigators have shown that polyfunctional T cells correlate best with ...

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

authors： Ndhlovu ZM,Oelke M,Schneck JP,Griffin DE

更新日期：2010-02-23 00:00:00

abstract：:Microtubule formation from lamb brain tubulin isolated by affinity chromatography and freed of exchangeable nucleotide requires GTP for maximal rate and extent of polymerization. The nucleotide analogs guanylylmethylenediphosphate and guanylylimidodiphosphate fail to replace GTP; in addition, neither the presence of m...

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

authors： Maccioni R,Seeds NW

更新日期：1977-02-01 00:00:00

abstract：:Cell couples have been formed by mixing an antigen- and Ia-specific cloned helper T-cell line with a B-cell hybridoma presenting the antigen. By immunofluorescence observations, we have shown that the microtubule-organizing center (MTOC) inside the helper T cell, but not in the bound antigen-presenting cell, becomes o...

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

authors： Kupfer A,Swain SL,Janeway CA Jr,Singer SJ

更新日期：1986-08-01 00:00:00

abstract：:Excitatory amino acid transporters (EAATs) buffer and remove synaptically released L-glutamate and maintain its concentrations below neurotoxic levels. EAATs also mediate a thermodynamically uncoupled substrate-gated anion conductance that may modulate cell excitability. Here, we demonstrate that modification of a cys...

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

authors： Seal RP,Shigeri Y,Eliasof S,Leighton BH,Amara SG

更新日期：2001-12-18 00:00:00

abstract：:Amputation of the zebrafish caudal fin stimulates regeneration of the dermal skeleton and reexpression of sonic hedgehog (shh)-signaling pathway genes. Expression patterns suggest a role for shh signaling in the secretion and patterning of the regenerating dermal bone, but a direct role has not been demonstrated. We e...

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

authors： Quint E,Smith A,Avaron F,Laforest L,Miles J,Gaffield W,Akimenko MA

更新日期：2002-06-25 00:00:00

abstract：:Harvey and Kirsten murine sarcoma viruses each encode a structurally and functionally related 21-kilodalton protein (p21), which is the transforming protein of each virus. Using probes from the 0.9-kilobase (kb) p21-coding region of each virus (called v-Ha-ras and v-Ki-ras, respectively), we have molecularly cloned fr...

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

authors： Chang EH,Gonda MA,Ellis RW,Scolnick EM,Lowy DR

更新日期：1982-08-01 00:00:00

abstract：:The surface layer of the oceans and other aquatic environments contains many bacteria that range in activity, from dormant cells to those with high rates of metabolism. However, little experimental evidence exists about the activity of specific bacterial taxa, especially rare ones. Here we explore the relationship bet...

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

authors： Campbell BJ,Yu L,Heidelberg JF,Kirchman DL

更新日期：2011-08-02 00:00:00

abstract：:Tramadol, previously only known as a synthetic analgesic, has now been found in the bark and wood of roots of the African medicinal tree Nauclea latifolia. At present, no direct evidence is available as to the biosynthetic pathway of its unusual skeleton. To provide guidance as to possible biosynthetic precursors, we ...

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

authors： Romek KM,Nun P,Remaud GS,Silvestre V,Taïwe GS,Lecerf-Schmidt F,Boumendjel A,De Waard M,Robins RJ

更新日期：2015-07-07 00:00:00

abstract：:The cancer stem cell hypothesis posits that tumors are derived from a single cancer-initiating cell with stem cell properties. The task of identifying and characterizing a single cancer-initiating cell with stem cell properties has proven technically difficult because of the scarcity of the cancer stem cells in the ti...

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

authors： Zucchi I,Sanzone S,Astigiano S,Pelucchi P,Scotti M,Valsecchi V,Barbieri O,Bertoli G,Albertini A,Reinbold RA,Dulbecco R

更新日期：2007-06-19 00:00:00

abstract：:Organic substances can adopt an amorphous solid or semisolid state, influencing the rate of heterogeneous reactions and multiphase processes in atmospheric aerosols. Here we demonstrate how molecular diffusion in the condensed phase affects the gas uptake and chemical transformation of semisolid organic particles. Flo...

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

authors： Shiraiwa M,Ammann M,Koop T,Pöschl U

更新日期：2011-07-05 00:00:00

abstract：:Elevated expression of the marORAB multiple antibiotic-resistance operon enhances the resistance of Escherichia coli to various medically significant antibiotics. Transcription of the operon is repressed in vivo by the marR-encoded protein, MarR, and derepressed by salicylate and certain antibiotics. The possibility t...

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

authors： Martin RG,Rosner JL

更新日期：1995-06-06 00:00:00

abstract：:The suprachiasmatic nucleus (SCN), the master circadian clock in mammals, sends major output signals to the subparaventricular zone (SPZ) and further to the paraventricular nucleus (PVN), the neural mechanism of which is largely unknown. In this study, the intracellular calcium levels were measured continuously in cul...

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

authors： Wu YE,Enoki R,Oda Y,Huang ZL,Honma KI,Honma S

更新日期：2018-10-02 00:00:00

abstract：:After treatment with nitrite, Japanese soy sauce was strongly mutagenic to Salmonella typhimurium TA100 without S9 mixture. Two precursors of the mutagen were isolated from Japanese soy sauce, and these were identified as (-)-(1S,3S)-1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid [(-)-(1S,3S)-MTCA] and i...

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

authors： Wakabayashi K,Ochiai M,Saitô H,Tsuda M,Suwa Y,Nagao M,Sugimura T

更新日期：1983-05-01 00:00:00

abstract：:Nanometer-scale pores have demonstrated potential for the electrical detection, quantification, and characterization of molecules for biomedical applications and the chemical analysis of polymers. Despite extensive research in the nanopore sensing field, there is a paucity of theoretical models that incorporate the in...

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

authors： Reiner JE,Kasianowicz JJ,Nablo BJ,Robertson JW

更新日期：2010-07-06 00:00:00

abstract：:Hierarchical cellular structures are ubiquitous in nature because of their low-density, high-specific properties, and multifunctionality. Inspired by these systems, we created lightweight ceramic architectures composed of closed-cell porous struts patterned in the form of hexagonal and triangular honeycombs by direct ...

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

authors： Muth JT,Dixon PG,Woish L,Gibson LJ,Lewis JA

更新日期：2017-02-21 00:00:00

abstract：:Stem cell therapy has emerged as a promising tool for the treatment of a variety of diseases. Previously, we have shown that Akt-modified mesenchymal stem cells mediate tissue repair through paracrine mechanisms. Using a comprehensive functional genomic strategy, we show that secreted frizzled related protein 2 (Sfrp2...

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

authors： Mirotsou M,Zhang Z,Deb A,Zhang L,Gnecchi M,Noiseux N,Mu H,Pachori A,Dzau V

更新日期：2007-01-30 00:00:00

abstract：:Positional cloning has already produced the sequences of more than 70 human genes associated with specific diseases. In addition to their medical importance, these genes are of interest as a set of human genes isolated solely on the basis of the phenotypic effect of the respective mutations. We analyzed the protein se...

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

authors： Mushegian AR,Bassett DE Jr,Boguski MS,Bork P,Koonin EV

更新日期：1997-05-27 00:00:00