Picosecond photodissociation and subsequent recombination processes in carbon monoxide hemoglobin.

abstract：:Gram-negative bacteria possess a characteristic outer membrane, of which the lipid A constituent elicits a strong host immune response through the Toll-like receptor 4 complex, and acts as a component of the permeability barrier to prevent uptake of bactericidal compounds. Lipid A species comprise the bulk of the oute...

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

authors： Dovala D,Rath CM,Hu Q,Sawyer WS,Shia S,Elling RA,Knapp MS,Metzger LE 4th

更新日期：2016-10-11 00:00:00

abstract：:The human pathogen Mycobacterium tuberculosis encodes a proteasome that carries out regulated degradation of bacterial proteins. It has been proposed that the proteasome contributes to nitrogen metabolism in M. tuberculosis, although this hypothesis had not been tested. Upon assessing M. tuberculosis growth in several...

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

authors： Becker SH,Jastrab JB,Dhabaria A,Chaton CT,Rush JS,Korotkov KV,Ueberheide B,Darwin KH

更新日期：2019-02-19 00:00:00

abstract：:Proper segregation of chromosomes in meiosis is essential to prevent miscarriages and birth defects. This requires that sister chromatids maintain cohesion at the centromere as cohesion is released on the chromatid arms when the homologs segregate at anaphase I. The Shugoshin proteins preserve centromere cohesion by p...

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

authors： Pinto BS,Orr-Weaver TL

更新日期：2017-12-05 00:00:00

abstract：:The mammalian anx7 gene codes for a Ca(2+)-activated GTPase, which supports Ca(2+)/GTP-dependent secretion events and Ca(2+) channel activities in vitro and in vivo. To test whether anx7 might be involved in Ca(2+) signaling in secreting pancreatic beta cells, we knocked out the anx7 gene in the mouse and tested the i...

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

authors： Srivastava M,Atwater I,Glasman M,Leighton X,Goping G,Caohuy H,Miller G,Pichel J,Westphal H,Mears D,Rojas E,Pollard HB

更新日期：1999-11-23 00:00:00

abstract：:Norepinephrine, epinephrine, and histamine cause a rapid increase in the concentration of adenosine 3':5'-cyclic monophosphate (cAMP) in a tumor astrocyte cell line derived from a primary culture of a human glioblastoma multiforme. The catecholamine-induced increase in cAMP is dependent on the cell density, being far ...

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

authors： Clark RB,Perkins JP

更新日期：1971-11-01 00:00:00

abstract：:We used a modified subtractive suppression hybridization to identify cellular genes that show altered expression in Burkitt lymphomas (BLs) in the presence of Epstein-Barr virus (EBV). Comparison of the gene expression patterns of an EBV-negative clone of the originally EBV-positive BL line Akata, with its Neo(R)-EBV ...

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

authors： Kiss C,Nishikawa J,Takada K,Trivedi P,Klein G,Szekely L

更新日期：2003-04-15 00:00:00

abstract：:It is widely accepted that modern humans originated in sub-Saharan Africa approximately 150-200 thousand years ago (ka), but their route of dispersal across the currently hyperarid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant approximately 120-90 ka, nort...

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

authors： Osborne AH,Vance D,Rohling EJ,Barton N,Rogerson M,Fello N

更新日期：2008-10-28 00:00:00

abstract：:The x-ray structure of rubredoxin has been refined by energy minimization. The computed structure is constrained to have standard bond lengths, bond angles, and planar trans peptide groups. Also, since most of the steric overlaps have been relieved, it has a very low energy. As judged by the root mean square (RMS) dev...

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

authors： Rasse D,Warme PK,Scheraga HA

更新日期：1974-09-01 00:00:00

abstract：:Social interactions are fundamental for human behavior, but the quantification of their neural underpinnings remains challenging. Here, we used hyperscanning functional MRI (fMRI) to study information flow between brains of human dyads during real-time social interaction in a joint attention paradigm. In a hardware se...

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

authors： Bilek E,Ruf M,Schäfer A,Akdeniz C,Calhoun VD,Schmahl C,Demanuele C,Tost H,Kirsch P,Meyer-Lindenberg A

更新日期：2015-04-21 00:00:00

abstract：:A codon-optimized mouse LINE-1 element, ORFeus, exhibits dramatically higher retrotransposition frequencies compared with its native long interspersed element 1 counterpart. To establish a retrotransposon-mediated mouse model with regulatable and potent mutagenic capabilities, we generated a tetracycline (tet)-regulat...

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

authors： O'Donnell KA,An W,Schrum CT,Wheelan SJ,Boeke JD

更新日期：2013-07-16 00:00:00

abstract：:Gamma-band synchronization adjusts the timing of excitatory and inhibitory inputs to a neuron. Neurons in the visual cortex are selective for stimulus orientation because of dynamic interactions between excitatory and inhibitory inputs. We hypothesized that these interactions and hence also orientation selectivity var...

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

authors： Womelsdorf T,Lima B,Vinck M,Oostenveld R,Singer W,Neuenschwander S,Fries P

更新日期：2012-03-13 00:00:00

abstract：:We report the optical conductivity in high-quality crystals of the chiral topological semimetal CoSi, which hosts exotic quasiparticles known as multifold fermions. We find that the optical response is separated into several distinct regions as a function of frequency, each dominated by different types of quasiparticl...

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

authors： Xu B,Fang Z,Sánchez-Martínez MÁ,Venderbos JWF,Ni Z,Qiu T,Manna K,Wang K,Paglione J,Bernhard C,Felser C,Mele EJ,Grushin AG,Rappe AM,Wu L

更新日期：2020-11-03 00:00:00

abstract：:Site-directed mutagenesis of selected residues of mammalian protein phosphatase 1 (PP-1) has been carried out to further define the mechanism of catalysis, activation by divalent cations, and inhibition by toxins and inhibitory proteins. Mutation of active site residues predicted to bind metals (N124D and H248N) resul...

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

authors： Huang HB,Horiuchi A,Goldberg J,Greengard P,Nairn AC

更新日期：1997-04-15 00:00:00

abstract：:The onset of autoimmunity in experimental rodent models and patients frequently correlates with a lymphopenic state. In this condition, the immune system has evolved compensatory homeostatic mechanisms that induce quiescent naive T cells to proliferate and differentiate into memory-like lymphocytes even in the apparen...

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

authors： Le Saout C,Mennechet S,Taylor N,Hernandez J

更新日期：2008-12-09 00:00:00

abstract：:The 24 human chromosome types of normal diploid fibroblast cell strain were classified into 15 groups by high-resolution flow cytometry on the basis of 33258 Hoechst fluorescence. Chromosomes associated with each group were flow sorted onto microscope slides and identified by quinacrine banding analysis. DNA cytophoto...

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

authors： Carrano AV,Gray JW,Langlois RG,Burkhart-Schultz KJ,Van Dilla MA

更新日期：1979-03-01 00:00:00

abstract：:Rhesus monkeys were immunized by multiple inoculations with purified, disrupted, noninfectious simian immunodeficiency virus (SIV) in adjuvant. Immunized monkeys developed anti-SIV antibodies detectable by whole-virus ELISA and by immunoblot reactivity; these antibodies had weak neutralizing activity. One week after t...

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

authors： Desrosiers RC,Wyand MS,Kodama T,Ringler DJ,Arthur LO,Sehgal PK,Letvin NL,King NW,Daniel MD

更新日期：1989-08-01 00:00:00

abstract：:Tubular membrane structures are widespread in eukaryotic cells, but the mechanisms underlying their formation and stability are not well understood. Previous work has focused on tube extrusion from cells and model membranes under the application of external forces. Here, we present novel membrane/polymer systems, wher...

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

authors： Li Y,Lipowsky R,Dimova R

更新日期：2011-03-22 00:00:00

abstract：:DNA was extracted from the remains of 35 ground sloths from various parts of North and South America. Two specimens of Mylodon darwinii, a species that went extinct at the end of the last glaciation, yielded amplifiable DNA. However, of the total DNA extracted, only approximately 1/1000 originated from the sloth, wher...

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

authors： Höss M,Dilling A,Currant A,Pääbo S

更新日期：1996-01-09 00:00:00

abstract：:The three-dimensional structure of alpha-cobra-toxin, the "long" neurotoxin from the venom of Naja naja siamensis, has been determined at 2.8-A resolution. Crystals grown as hexagonal needles have space group P6522 with unit cell parameters a = b = 74.59 A, c = 42.89 A; one molecule per asymmetric unit. Phases were de...

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

authors： Walkinshaw MD,Saenger W,Maelicke A

更新日期：1980-05-01 00:00:00

abstract：:The MYC family of cellular oncogenes includes c-Myc, N-myc, and L-myc, which encode transcriptional regulators involved in the control of cell proliferation and death. Accordingly, these genes become aberrantly activated and expressed in specific types of cancers. For example, c-Myc translocations occur frequently in ...

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

authors： Gostissa M,Ranganath S,Bianco JM,Alt FW

更新日期：2009-02-17 00:00:00

abstract：:By using single-molecule multiparameter fluorescence detection, fluorescence resonance energy transfer experiments, and newly developed data analysis methods, this study demonstrates directly the existence of three structurally distinct forms of reverse transcriptase (RT):nucleic acid complexes in solution. Single-mol...

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

authors： Rothwell PJ,Berger S,Kensch O,Felekyan S,Antonik M,Wöhrl BM,Restle T,Goody RS,Seidel CA

更新日期：2003-02-18 00:00:00

abstract：:Superhard metals are of interest as possible replacements with enhanced properties over the metal carbides commonly used in cutting, drilling, and wear-resistant tooling. Of the superhard metals, the highest boride of tungsten--often referred to as WB4 and sometimes as W(1-x)B3--is one of the most promising candidates...

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

authors： Lech AT,Turner CL,Mohammadi R,Tolbert SH,Kaner RB

更新日期：2015-03-17 00:00:00

abstract：:Chromosomes condense during mitotic entry to facilitate their segregation. Condensation is typically assayed in fixed preparations, limiting analysis of contributing factors. Here, we describe a quantitative method to monitor condensation kinetics in living cells expressing GFP fused to a core histone. We demonstrate ...

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

authors： Maddox PS,Portier N,Desai A,Oegema K

更新日期：2006-10-10 00:00:00

abstract：:A mathematical analysis of the formation of hemolytic plaques in agar is presented. The results can be used to calculate the rate constant for antigen-antibody association and the distribution of antibody secretion rates. The limitations of the treatment and estimates of the expected errors involved are briefly discus...

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

authors： De Lisi CP,Bell GI

更新日期：1974-01-01 00:00:00

abstract：:Operating rooms (ORs) are inhabited by hierarchical, mixed-gender clinical teams that are often prone to conflict. In evolutionary terms, one expects more within- than between-gender rivalries, especially since the OR is a place where all sorts of social interactions occur, not merely technical communications. To docu...

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

authors： Jones LK,Jennings BM,Higgins MK,de Waal FBM

更新日期：2018-07-17 00:00:00

abstract：:RNA was synthesized in vitro from a T3 DNA template by T3 RNA polymerase and subsequently separated into seven discrete size classes (molecular weights ranging between 0.21 x 10(6) and 6.2 x 10(6)) by electrophoresis in polyacrylamide slab gels. RNase T1-generated 3'-terminal oligonucleotide fragments were then select...

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

authors： Majumder HK,Maitra U,Rosenberg M

更新日期：1979-10-01 00:00:00

abstract：:Soluble extracts of adenovirus-infected HeLa cell nuclei support DNA replication on exogenous adenovirus DNA templates. Conditions of synthesis using both wild-type and temperature-sensitive extracts have been defined. Nuclear extracts prepared from cells permissively infected with the adenovirus mutant H5ts125 expres...

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

authors： Kaplan LM,Ariga H,Hurwitz J,Horwitz MS

更新日期：1979-11-01 00:00:00

abstract：:The enzymic activity of crystalline mitochondrial aspartate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) was determined in suspensions of noncrosslinked microcrystals in 30% (wt/vol) polyethylene glycol. The crystals (average dimensions, 22 x 5 x 0.8 micron) were small enough to preclude ...

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

authors： Kirsten H,Gehring H,Christen P

更新日期：1983-04-01 00:00:00

abstract：:Nodules harboring nitrogen-fixing rhizobia are a well-known trait of legumes, but nodules also occur in other plant lineages, with rhizobia or the actinomycete Frankia as microsymbiont. It is generally assumed that nodulation evolved independently multiple times. However, molecular-genetic support for this hypothesis ...

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

authors： van Velzen R,Holmer R,Bu F,Rutten L,van Zeijl A,Liu W,Santuari L,Cao Q,Sharma T,Shen D,Roswanjaya Y,Wardhani TAK,Kalhor MS,Jansen J,van den Hoogen J,Güngör B,Hartog M,Hontelez J,Verver J,Yang WC,Schijlen E,Repin

更新日期：2018-05-15 00:00:00

abstract：:Insulin activates sterol regulatory element-binding protein-1c (SREBP-1c) in liver, thereby increasing fatty acid and triglyceride synthesis. We created a line of transgenic rats that produce epitope-tagged human SREBP-1c in liver under control of the constitutive apolipoprotein E promoter/enhancer. This system allows...

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

authors： Owen JL,Zhang Y,Bae SH,Farooqi MS,Liang G,Hammer RE,Goldstein JL,Brown MS

更新日期：2012-10-02 00:00:00