Sum rules and determination of exciton coupling using absorption and circular dichroism spectra of biological polymers.

abstract：:Chinese hamster-human somatic cell hybrids were analyzed for the expression of human galactose-1-phosphate uridyltransferase (GALT; UDPglucose:alpha-D-galactose-1-phosphate uridyltransferase, EC 2.7.7.12) by electrophoresis and for the presence of human chromosomes cytogenetically with the aid of Q-banding. Three of t...

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

authors： Mohandas T,Sparkes RS,Sparkes MC,Shulkin JD

更新日期：1977-12-01 00:00:00

abstract：:The stress inoculation hypothesis presupposes that brief intermittent stress exposure early in life induces the development of subsequent stress resistance in human and nonhuman primates. Rodent studies, however, suggest a role for maternal care rather than stress exposure per se (i.e., the maternal mediation hypothes...

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

authors： Parker KJ,Buckmaster CL,Sundlass K,Schatzberg AF,Lyons DM

更新日期：2006-02-21 00:00:00

abstract：:The hydroxyl radical (OH) is the primary oxidant in the troposphere, and the impact of its fluctuations on the methane budget has been disputed in recent years, however measurements of OH are insufficient to characterize global interannual fluctuations relevant for methane. Here, we use a 6,000-y control simulation of...

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

authors： Turner AJ,Fung I,Naik V,Horowitz LW,Cohen RC

更新日期：2018-09-04 00:00:00

abstract：:Glutamate transport by the excitatory amino acid carrier EAAC1 is known to be reversible. Thus, glutamate can either be taken up into cells, or it can be released from cells through reverse transport, depending on the electrochemical gradient of the co- and countertransported ions. However, it is unknown how fast and ...

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

authors： Zhang Z,Tao Z,Gameiro A,Barcelona S,Braams S,Rauen T,Grewer C

更新日期：2007-11-13 00:00:00

abstract：:Unfolded RNase A is known to contain an equilibrium mixture of two forms, a slow-folding form (U(1)) and a fast-folding form (U(2)). If U(1) is produced after unfolding by the slow cis-trans isomerization of proline residues about X-Pro imide bonds, then the formation of U(1) should be catalyzed by strong acids. There...

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

authors： Schmid FX,Baldwin RL

更新日期：1978-10-01 00:00:00

abstract：:Obesity is associated with increased risk for developing pancreatic cancer, and it is suggested that insulin resistance provides the missing link. Here we demonstrate that under the context of genetic susceptibility, a high fat diet (HFD) predisposes mice with oncogenic K-ras activation to accelerated pancreatic intra...

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

authors： Khasawneh J,Schulz MD,Walch A,Rozman J,Hrabe de Angelis M,Klingenspor M,Buck A,Schwaiger M,Saur D,Schmid RM,Klöppel G,Sipos B,Greten FR,Arkan MC

更新日期：2009-03-03 00:00:00

abstract：:Both plants and animals require the activity of proteins containing nucleotide binding (NB) domain and leucine-rich repeat (LRR) domains for proper immune system function. NB-LRR proteins in plants (NLR proteins in animals) also require conserved regulation via the proteins SGT1 and cytosolic HSP90. RAR1, a protein sp...

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

authors： Hubert DA,He Y,McNulty BC,Tornero P,Dangl JL

更新日期：2009-06-16 00:00:00

abstract：:The exopolysaccharide alginate is a major virulence factor in the pathogenicity of Pseudomonas aeruginosa infecting the lungs of cystic fibrosis (CF) patients. Alginate synthesis by P. aeruginosa is believed to occur in response to environmental signals present in the CF lung. Transcription of a critical alginate bios...

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

authors： Roychoudhury S,Sakai K,Chakrabarty AM

更新日期：1992-04-01 00:00:00

abstract：:Unit-resolution mass spectra have been obtained for peptides as large as 17 kDa, providing information on impurities and adduct ions, as well as accurate molecular weight values. Electrospray ionization produces many multiply-charged species of the same mass; isotopic peak resolution provides direct charge state assig...

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

authors： Loo JA,Quinn JP,Ryu SI,Henry KD,Senko MW,McLafferty FW

更新日期：1992-01-01 00:00:00

abstract：:The action of cyclin-dependent kinases (CDKs) is regulated by phosphorylation, cyclin levels, the abundance of CDK inhibitors, and, as recently has been shown for cyclin B/cdc2, their localization. It is unclear how localization regulates the action of cyclin E/Cdk2 and its inhibitors. Here, we show that the closest k...

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

authors： Swanson C,Ross J,Jackson PK

更新日期：2000-07-05 00:00:00

abstract：:We have determined the nucleotide sequences of the Klebsiella pneumoniae nifL (regulation of N2 fixation genes) and the Escherichia coli glnA (glutamine synthetase) promoters. We compared these sequences with the published sequences of three other promoters that, like the nifL and glnA promoters, are activated by the ...

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

authors： Ow DW,Sundaresan V,Rothstein DM,Brown SE,Ausubel FM

更新日期：1983-05-01 00:00:00

abstract：:G protein-coupled receptors mediate biological signals by stimulating nucleotide exchange in heterotrimeric G proteins (Galphabetagamma). Receptor dimers have been proposed as the functional unit responsible for catalytic interaction with Galphabetagamma. To investigate whether a G protein-coupled receptor monomer can...

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

authors： Ernst OP,Gramse V,Kolbe M,Hofmann KP,Heck M

更新日期：2007-06-26 00:00:00

abstract：:A careful review of the literature in political science and neighboring social science disciplines shows that prevailing assumptions in the international development policy community about improved governance as a principal mechanism to reduce poverty in Africa rests more on faith than science. Conventional policy mod...

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

authors： Hyden G

更新日期：2007-10-23 00:00:00

abstract：:During reverse transcription of retroviral RNA, synthesis of (-) strand DNA is primed by a cellular tRNA that anneals to an 18-nt primer binding site within the 5' long terminal repeat. For (+) strand synthesis using a (-) strand DNA template linked to the tRNA primer, only the first 18 nt of tRNA are replicated to re...

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

authors： Burnett BP,McHenry CS

更新日期：1997-07-08 00:00:00

abstract：:The difficulty of achieving robust functional expression of insect nicotinic acetylcholine receptors (nAChRs) has hampered our understanding of these important molecular targets of globally deployed neonicotinoid insecticides at a time when concerns have grown regarding the toxicity of this chemotype to insect pollina...

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

authors： Ihara M,Furutani S,Shigetou S,Shimada S,Niki K,Komori Y,Kamiya M,Koizumi W,Magara L,Hikida M,Noguchi A,Okuhara D,Yoshinari Y,Kondo S,Tanimoto H,Niwa R,Sattelle DB,Matsuda K

更新日期：2020-07-14 00:00:00

abstract：:Heat-shock protein of 90 kDa (Hsp90) is an essential molecular chaperone that adopts different 3D structures associated with distinct nucleotide states: a wide-open, V-shaped dimer in the apo state and a twisted, N-terminally closed dimer with ATP. Although the N domain is known to mediate ATP binding, how Hsp90 sense...

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

authors： Sung N,Lee J,Kim JH,Chang C,Joachimiak A,Lee S,Tsai FT

更新日期：2016-03-15 00:00:00

abstract：:The subventricular zone remains mitotically active throughout life in rodents. Studies with tritiated thymidine, which is incorporated into the DNA of mitotic cells, have revealed that the rodent subventricular zone produces neuroblasts that migrate toward the olfactory bulb along the rostral migratory stream. A simil...

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

authors： Bernier PJ,Bedard A,Vinet J,Levesque M,Parent A

更新日期：2002-08-20 00:00:00

abstract：:Variation is the raw material for natural selection, but the factors shaping variation are still poorly understood. Genetic and developmental interactions can direct variation, but there has been little synthesis of these effects with the extrinsic factors that can shape biodiversity over large scales. The study of ph...

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

authors： Goswami A,Binder WJ,Meachen J,O'Keefe FR

更新日期：2015-04-21 00:00:00

abstract：:Assessing temporal variability in extreme rainfall events before the historical era is complicated by the sparsity of long-term "direct" storm proxies. Here we present a 2,200-y-long, accurate, and precisely dated record of cave flooding events from the northwest Australian tropics that we interpret, based on an integ...

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

authors： Denniston RF,Villarini G,Gonzales AN,Wyrwoll KH,Polyak VJ,Ummenhofer CC,Lachniet MS,Wanamaker AD Jr,Humphreys WF,Woods D,Cugley J

更新日期：2015-04-14 00:00:00

abstract：:The pore-forming peptide amoebapore is considered part of the cytolytic armament of pathogenic Entamoeba histolytica. Amoebapore is composed of 77 amino acid residues arranged in four alpha-helical domains. For structure-function analysis, synthetic peptides were constructed corresponding to these four domains: H1 (re...

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

authors： Leippe M,Andrä J,Müller-Eberhard HJ

更新日期：1994-03-29 00:00:00

abstract：:We modeled the behavior of recessive mutations with deleterious effects to either the sporophyte or the gametophyte, or both, in polysomic tetraploid populations by allowing for varying levels of double reduction, mutation, and self-fertilization. Double reduction causes a decrease of the equilibrium frequencies of de...

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

authors： Butruille DV,Boiteux LS

更新日期：2000-06-06 00:00:00

abstract：:Autoantibodies directed against the cell surface receptors for insulin are found in some patients with extreme insulin resistance. These antibodies specifically inhibit the binding of insulin to its receptor. A purified IgG fraction from one patient's plasma was labeled with 125I. The 125I-labeled antireceptor antibod...

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

authors： Jarrett DB,Roth J,Kahn CR,Flier JS

更新日期：1976-11-01 00:00:00

abstract：:A mol of creatine kinase (EC 2.7.3.2), an enzyme with two identical subunits can be titrated very rapidly and stoichiometrically with 2 mol of 2-chloromercuri-4-nitrophenol, an environmentally sensitive chromophoric probe specific for thiols. Chemical modification does not inactivate the enzyme nor can the reaction be...

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

authors： Quiocho FE,Thomson JW

更新日期：1973-10-01 00:00:00

abstract：:Sponges (Porifera), the simplest and earliest multicellular organisms, are thought to have evolved from their unicellular ancestors about 1 billion years ago by developing cell-recognition and adhesion mechanisms to discriminate against "non-self." Consequently, they are used as models for investigating recognition ph...

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

authors： Haseley SR,Vermeer HJ,Kamerling JP,Vliegenthart JF

更新日期：2001-07-31 00:00:00

abstract：:The three most common methods of sterilization in use today are ethylene oxide exposure, gamma-irradiation, and steam sterilization. Each of these methods has serious limitations for the sterilization of some materials used in medicine, especially thermally and hydrolytically sensitive polymers by themselves and in co...

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

authors： Dillow AK,Dehghani F,Hrkach JS,Foster NR,Langer R

更新日期：1999-08-31 00:00:00

abstract：:Primary transcripts made in vitro on bacteriophage T4 DNA by RNA polymerase isolated from normal or T4-infected Escherichia coli were compared by gel electrophoresis. Bacteriophage-modified RNA polymerase fails to initiate transcription at certain promoters recognized by unmodified enzyme. In the T4tRNA gene region, o...

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

authors： Goldfarb A

更新日期：1981-06-01 00:00:00

abstract：:In an investigation to determine how proteins are localized within the nucleus of a cell, we demonstrate that the restriction endonuclease EcoRI is able to enter and function within the nucleus of Saccharomyces cerevisiae when this prokaryotic protein is synthesized in vivo. The EcoRI endonuclease was produced in yeas...

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

authors： Barnes G,Rine J

更新日期：1985-03-01 00:00:00

abstract：:The exquisite NMR spectral sensitivity and negligible reactivity of hyperpolarized xenon-129 (HP(129)Xe) make it attractive for a number of magnetic resonance applications; moreover, HP(129)Xe embodies an alternative to rare and nonrenewable (3)He. However, the ability to reliably and inexpensively produce large quant...

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

authors： Nikolaou P,Coffey AM,Walkup LL,Gust BM,Whiting N,Newton H,Barcus S,Muradyan I,Dabaghyan M,Moroz GD,Rosen MS,Patz S,Barlow MJ,Chekmenev EY,Goodson BM

更新日期：2013-08-27 00:00:00

abstract：:In human financial and social systems, exchanges of information among individuals cause speculative bubbles, behavioral cascades, and other correlated actions that profoundly influence system-level function. Exchanges of information are also widespread in ecological systems, but their effects on ecosystem-level proces...

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

authors： Gil MA,Hein AM

更新日期：2017-05-02 00:00:00

abstract：:Developmentally regulated genes in Drosophila, which are conserved through evolution, are potential candidates for key functions in biological processes such as cell cycle, programmed cell death, and cancer. We report cloning and characterization of the human homologue of the Drosophila seven in absentia gene (HUMSIAH...

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

authors： Nemani M,Linares-Cruz G,Bruzzoni-Giovanelli H,Roperch JP,Tuynder M,Bougueleret L,Cherif D,Medhioub M,Pasturaud P,Alvaro V,der Sarkissan H,Cazes L,Le Paslier D,Le Gall I,Israeli D,Dausset J,Sigaux F,Chumakov I,Oren M,

更新日期：1996-08-20 00:00:00