Detection of synchronous brain activity in white matter tracts at rest and under functional loading.

abstract：:Tetrodotoxin was infused into the suprachiasmatic nuclei of unanesthetized and unrestrained rats continuously for 14 days. The internal timekeeping mechanism of the circadian pacemaker in the nuclei continued to oscillate unaffected by this treatment, although the toxin reversibly blocked function of both the input pa...

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

authors： Schwartz WJ,Gross RA,Morton MT

更新日期：1987-03-01 00:00:00

abstract：:GTP hydrolysis by elongation factor Tu (EF-Tu), a translational GTPase that delivers aminoacyl-tRNAs to the ribosome, plays a crucial role in decoding and translational fidelity. The basic reaction mechanism and the way the ribosome contributes to catalysis are a matter of debate. Here we use mutational analysis in co...

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

authors： Maracci C,Peske F,Dannies E,Pohl C,Rodnina MV

更新日期：2014-10-07 00:00:00

abstract：:Catalysis at organophilic silica-rich surfaces of zeolites and feldspars might generate replicating biopolymers from simple chemicals supplied by meteorites, volcanic gases, and other geological sources. Crystal-chemical modeling yielded packings for amino acids neatly encapsulated in 10-ring channels of the molecular...

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

authors： Smith JV,Arnold FP Jr,Parsons I,Lee MR

更新日期：1999-03-30 00:00:00

abstract：:Horizontal drilling and hydraulic fracturing have enhanced energy production but raised concerns about drinking-water contamination and other environmental impacts. Identifying the sources and mechanisms of contamination can help improve the environmental and economic sustainability of shale-gas extraction. We analyze...

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

authors： Darrah TH,Vengosh A,Jackson RB,Warner NR,Poreda RJ

更新日期：2014-09-30 00:00:00

abstract：:Dictyostelium actin was shown to become phosphorylated on Tyr-53 late in the developmental cycle and when cells in the amoeboid stage are subjected to stress but the phosphorylated actin had not been purified and characterized. We have separated phosphorylated and unphosphorylated actin and shown that Tyr-53 phosphory...

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

authors： Liu X,Shu S,Hong MS,Levine RL,Korn ED

更新日期：2006-09-12 00:00:00

abstract：:Partial, unilateral nigrostriatal lesions of varying severity were produced in rats by injecting graded doses of 6-hydroxydopamine into the substantia nigra. Formation of the dopamine metabolites dihydroxyphenylacetic acid and homovanillic acid in each surviving nigrostriatal neuron (estimated by the ratios of dihydro...

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

authors： Melamed E,Hefti F,Wurtman RJ

更新日期：1980-07-01 00:00:00

abstract：:Rising sea levels and increased storminess are expected to accelerate the erosion of soft-cliff coastlines, threatening coastal infrastructure and livelihoods. To develop predictive models of future coastal change we need fundamentally to know how rapidly coasts have been eroding in the past, and to understand the dri...

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

authors： Hurst MD,Rood DH,Ellis MA,Anderson RS,Dornbusch U

更新日期：2016-11-22 00:00:00

abstract：:Analysis of commercial catches reveals a serial depletion of some oceanic fish stocks over time, resulting in fisheries focusing on increasingly smaller species closer to the base of the food chain. This effect, described as fishing down the marine food web, is observed when the trophic level of the catch declines ove...

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

authors： Dunlop ES,Goto D,Jackson DA

更新日期：2019-10-01 00:00:00

abstract：:Single strands of DNA serve, in rare instances, as promoters for transcription; duplex DNA promoters with individual strands that also have a promoter capacityfunction have not been described. We show that the nontranscribed strand of the Saccharomyces cerevisiae U6 snRNA gene directs transcription initiation factor I...

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

authors： Schroder O,Geiduschek EP,Kassavetis GA

更新日期：2003-02-04 00:00:00

abstract：:Transgenic mice have been used to address the issue of the oncogenic potential of mutant guanine nucleotide stimulatory factor (Gs) alpha subunit in the thyroid gland. The expression of the mutant Arg-201-->His Gs alpha subunit transgene has been directed to murine thyroid epithelial cells by bovine thyroglobulin prom...

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

authors： Michiels FM,Caillou B,Talbot M,Dessarps-Freichey F,Maunoury MT,Schlumberger M,Mercken L,Monier R,Feunteun J

更新日期：1994-10-25 00:00:00

abstract：:The perceptual quality of odors usually is robust to variability in concentration. However, maps of neural activation across the olfactory bulb glomerular layer are not stable in this respect; rather, glomerular odor representations both broaden and intensify as odorant concentrations are increased. The relative level...

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

authors： Cleland TA,Johnson BA,Leon M,Linster C

更新日期：2007-02-06 00:00:00

abstract：:Analyses of amino-acid sequences of the total cell-free products programmed by the mRNA of MOPC-104E gamma light (L)-chain show that over 95% of the products have sequences of a distinct protein that correspond to the L-chain precursor. In this precursor an extra piece is coupled to the NH2-terminus of the mature L-ch...

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

authors： Burstein Y,Kantour F,Schechter I

更新日期：1976-08-01 00:00:00

abstract：:We used 5,6-dichloro-beta D-ribofuranosyl-benzimidazole (DRB), a selective and reversible inhibitor of mRNA production, to investigate the regulation of the pathway leading to resistance to viruses in cells treated with interferon (IF). DRB allows initiation of transcription but promotes premature termination of the n...

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

authors： Gordon I,Stevenson D

更新日期：1980-01-01 00:00:00

abstract：:An acetone extract of chloroplast particles, when layered on an aqueous surface, exhibited light-dependent phosphorylation. Studies with the firefly-tail enzyme assay, as well as with (32)P-labeled inorganic phosphate, show an initial release of adenosine triphosphate (a step that is apparently only light-triggered), ...

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

authors： McPhee J,Brody SS

更新日期：1973-01-01 00:00:00

abstract：:A paradox in bone tissue is that tissue-level strains due to animal and human locomotion are too small to initiate intracellular chemical responses directly. A model recently was proposed to resolve this paradox, which predicts that the fluid flow through the pericellular matrix in the lacunar-canalicular porosity due...

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

authors： Han Y,Cowin SC,Schaffler MB,Weinbaum S

更新日期：2004-11-23 00:00:00

abstract：:Many infectious viruses coevolved with the vertebrate immune system. During the assembly of enveloped viruses, lipid ordered domains of the host cell plasma membrane, called lipid rafts, frequently function as a natural meeting point for viral proteins. The role of lipid rafts in the organization of complex combinatio...

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

authors： Derdak SV,Kueng HJ,Leb VM,Neunkirchner A,Schmetterer KG,Bielek E,Majdic O,Knapp W,Seed B,Pickl WF

更新日期：2006-08-29 00:00:00

abstract：:Mitochondrial membrane potentials and resistances have been determined under various metabolic conditions by the use of piezoelectric-driven microelectrodes. The mean state 3 potentials (about +19 mv) are higher than the potentials in state 4 (about +9 mv). DNP in uncoupling concentrations or KCN have no significant e...

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

authors： Tupper JT,Tedeschi H

更新日期：1969-07-01 00:00:00

abstract：:Ezrin plays a key role in coupling signal transduction to cortical cell organization. This actin-membrane linker undergoes a series of conformational changes that modulate its interactions with various partners and its localization in membrane or cytosolic pools. Its mobility and exchange rates within and between thes...

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

authors： Coscoy S,Waharte F,Gautreau A,Martin M,Louvard D,Mangeat P,Arpin M,Amblard F

更新日期：2002-10-01 00:00:00

abstract：:Many of the world's around 6,000 languages are in danger of disappearing as people give up use of a minority language in favor of the majority language in a process called language shift. Language shift can be monitored on a large scale through the use of mathematical models by way of differential equations, for examp...

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

authors： Prochazka K,Vogl G

更新日期：2017-04-25 00:00:00

abstract：:Establishment, specification, and validation of synaptic connections are thought to be mediated by interactions between pre- and postsynaptic cell-adhesion molecules. Arguably, the best-characterized transsynaptic interactions are formed by presynaptic neurexins, which bind to diverse postsynaptic ligands. In a proteo...

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

authors： Sterky FH,Trotter JH,Lee SJ,Recktenwald CV,Du X,Zhou B,Zhou P,Schwenk J,Fakler B,Südhof TC

更新日期：2017-02-14 00:00:00

abstract：:The activity of leukotriene A4 (LTA4) synthase in crude human leukocyte homogenates was found to have a similar requirement for Ca2+ and ATP as had been noted previously for 5-lipoxygenase activity. Purification of the 5-lipoxygenase using ammonium sulfate fractionation, AcA 44 gel-filtration chromatography, and HPLC ...

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

authors： Rouzer CA,Matsumoto T,Samuelsson B

更新日期：1986-02-01 00:00:00

abstract：:Paracoccidioidomycosis, a disease caused by Paracoccidioides brasiliensis, which is endemic to Latin America, is much more common in men than women, suggesting a role for hormonal factors. We recently showed that two other yeasts possess steroid binding proteins and postulated that these receptor-like molecules repres...

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

authors： Loose DS,Stover EP,Restrepo A,Stevens DA,Feldman D

更新日期：1983-12-01 00:00:00

abstract：:The adenoviral E1A oncogene sensitizes mammalian cells to tumor necrosis factor-alpha (TNF-alpha), in part by repressing the nuclear factor-kappa B (NF-kappa B)-dependent defense against this cytokine. Other E1A activities involve binding to either p300/cyclic AMP response element-binding protein (CBP) or retinoblasto...

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

authors： Cook JL,Walker TA,Worthen GS,Radke JR

更新日期：2002-07-23 00:00:00

abstract：:Time courses of 13C labeling from alanine and ethanol in perfused mouse livers have been followed by NMR. The enrichment at specific carbons of glucose, glutamate, glutamine, aspartate, acetate, acetoacetate, beta-hydroxybutyrate, and lactate has been measured. The specific labeling of glutamate in the presence of lab...

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

authors： Cohen SM,Shulman RG,McLaughlin AC

更新日期：1979-10-01 00:00:00

abstract：:In vivo expression technology (IVET) has been used to identify > 100 Salmonella typhimurium genes that are specifically expressed during infection of BALB/c mice and/or murine cultured macrophages. Induction of these genes is shown to be required for survival in the animal under conditions of the IVET selection. One c...

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

authors： Heithoff DM,Conner CP,Hanna PC,Julio SM,Hentschel U,Mahan MJ

更新日期：1997-02-04 00:00:00

abstract：:Saccharomyces cerevisiae translation initiation factor eIF-4A, an RNA helicase of the Asp-Glu-Ala-Asp (DEAD) box protein family, was mutated in the putative ATP binding site and expressed in Escherichia coli. Mutant proteins with alanine at position 66 replaced by glycine [eIF-4A(A66G)] or valine [eIF-4A(A66V)] were p...

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

authors： Blum S,Schmid SR,Pause A,Buser P,Linder P,Sonenberg N,Trachsel H

更新日期：1992-08-15 00:00:00

abstract：:Priming of cytotoxic T lymphocytes (CTLs) by dendritic cells (DCs) is crucial for elimination of pathogens and malignant cells. To activate CTLs, DCs present antigenic peptide-complexed MHC class I molecules (MHC-I) that will be recognized by the CTLs with T cell receptors and CD8 molecules. Here we show that paired I...

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

authors： Endo S,Sakamoto Y,Kobayashi E,Nakamura A,Takai T

更新日期：2008-09-23 00:00:00

abstract：:Female mosquitoes feed sequentially on carbohydrates (nectar) and proteins (blood) during each gonadotrophic cycle to become reproductively competent and effective disease vectors. Accordingly, metabolism is synchronized to support this reproductive cyclicity. However, regulatory pathways linking metabolism to reprodu...

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

authors： Ling L,Raikhel AS

更新日期：2021-02-09 00:00:00

abstract：:Fermions need to satisfy the Pauli exclusion principle: no two can be in the same state. This restriction is most compactly expressed in a second quantization formalism by the requirement that the creation and annihilation operators of the electrons satisfy anticommutation relations. The usual classical limit of quant...

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

authors： Levine RD

更新日期：2000-02-29 00:00:00

abstract：:A numerical algorithm is applied to the Greenland Ice Sheet Project 2 (GISP2) dust record from Greenland to remove the abrupt changes in dust flux associated with the Dansgaard-Oeschger (D-O) oscillations of the last glacial period. The procedure is based on the assumption that the rapid changes in dust are associated...

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

authors： Barker S,Knorr G

更新日期：2007-10-30 00:00:00