Atmospheric carbon dioxide levels for the last 500 million years.

abstract：:Life history events, such as traumatic stress, illness, or starvation, can influence us through molecular changes that are recorded in a pattern of characteristic chromatin modifications. These modifications are often associated with adaptive adjustments in gene expression that can persist throughout the lifetime of t...

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

authors： Demoinet E,Li S,Roy R

更新日期：2017-03-28 00:00:00

abstract：:We show that the diverse ecoregions of Madagascar share one distinctive climatic feature: unpredictable intra- or interannual precipitation compared with other regions with comparable rainfall. Climatic unpredictability is associated with unpredictable patterns of fruiting and flowering. It is argued that these featur...

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

authors： Dewar RE,Richard AF

更新日期：2007-08-21 00:00:00

abstract：:The generation of toxic oligomers during the aggregation of the amyloid-β (Aβ) peptide Aβ42 into amyloid fibrils and plaques has emerged as a central feature of the onset and progression of Alzheimer's disease, but the molecular pathways that control pathological aggregation have proved challenging to identify. Here, ...

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

authors： Cohen SI,Linse S,Luheshi LM,Hellstrand E,White DA,Rajah L,Otzen DE,Vendruscolo M,Dobson CM,Knowles TP

更新日期：2013-06-11 00:00:00

abstract：:The Abeta peptide of Alzheimer disease is derived from the proteolytic processing of the amyloid precursor proteins (APP), which are considered type I transmembrane glycoproteins. Recently, however, soluble forms of full-length APP were also detected in several systems including chromaffin granules. In this report we ...

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

authors： Efthimiopoulos S,Vassilacopoulou D,Ripellino JA,Tezapsidis N,Robakis NK

更新日期：1996-07-23 00:00:00

abstract：:A biologically active vitamin D(3) metabolite ("peak V metabolite") more polar than 25-hydroxycholecalciferol has been isolated from chicken intestines in pure form as a mono(trimethylsilyl)ether derivative. The molecule has been identified as 1,25-dihydroxycholecalciferol by means of mass spectrometry, ultraviolet ab...

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

authors： Holick MF,Schnoes HK,DeLuca HF

更新日期：1971-04-01 00:00:00

abstract：:Many changes have been described in the brains of Alzheimer's disease (AD) patients, including loss of neurons and formation of senile plaques and neurofibrillary tangles. The molecular mechanisms underlying these pathologies are unclear. Northern blot, dot-blot, and reverse transcription-coupled PCR analyses have dem...

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

authors： Chow N,Cox C,Callahan LM,Weimer JM,Guo L,Coleman PD

更新日期：1998-08-04 00:00:00

abstract：:HLA-I molecules play a central role in antigen presentation. They typically bind 9- to 12-mer peptides, and their canonical binding mode involves anchor residues at the second and last positions of their ligands. To investigate potential noncanonical binding modes, we collected in-depth and accurate HLA peptidomics da...

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

authors： Guillaume P,Picaud S,Baumgaertner P,Montandon N,Schmidt J,Speiser DE,Coukos G,Bassani-Sternberg M,Filippakopoulos P,Gfeller D

更新日期：2018-05-15 00:00:00

abstract：:We analyzed the distribution of the cauliflower mosaic virus (CaMV) aphid transmission factor (ATF), produced via a baculovirus recombinant, within Sf9 insect cells. Immunogold labeling revealed that the ATF colocalizes with an atypical cytoskeletal network. Detailed observation by electron microscopy demonstrated tha...

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

authors： Blanc S,Schmidt I,Vantard M,Scholthof HB,Kuhl G,Esperandieu P,Cerutti M,Louis C

更新日期：1996-12-24 00:00:00

abstract：:Many bacterial pathogens produce diffusible signal factor (DSF)-type quorum sensing (QS) signals in modulation of virulence and biofilm formation. Previous work on Xanthomonas campestris showed that the RpfC/RpfG two-component system is involved in sensing and responding to DSF signals, but little is known in other mi...

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

authors： Deng Y,Schmid N,Wang C,Wang J,Pessi G,Wu D,Lee J,Aguilar C,Ahrens CH,Chang C,Song H,Eberl L,Zhang LH

更新日期：2012-09-18 00:00:00

abstract：:Trypanosomosis, or sleeping sickness, is a major disease constraint on livestock productivity in sub-Saharan Africa. To identify quantitative trait loci (QTL) controlling resistance to trypanosomosis in cattle, an experimental cross was made between trypanotolerant African N'Dama (Bos taurus) and trypanosusceptible im...

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

authors： Hanotte O,Ronin Y,Agaba M,Nilsson P,Gelhaus A,Horstmann R,Sugimoto Y,Kemp S,Gibson J,Korol A,Soller M,Teale A

更新日期：2003-06-24 00:00:00

abstract：:The mapping of eye-specific, geniculocortical inputs to primary visual cortex (V1) is highly sensitive to the balance of correlated activity between the two eyes during a restricted postnatal critical period for ocular dominance plasticity. This critical period is likely to have amplified expression of genes and prote...

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

authors： Lyckman AW,Horng S,Leamey CA,Tropea D,Watakabe A,Van Wart A,McCurry C,Yamamori T,Sur M

更新日期：2008-07-08 00:00:00

abstract：:In Escherichia coli, AK I- HDH I and AK II- HDH II are two bifunctional proteins, derived from a common ancestor, that catalyze the first and third reactions of the common pathway leading to threonine and methionine. An extensive amino acid sequence comparison of both molecules reveals two main features on each of the...

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

authors： Ferrara P,Duchange N,Zakin MM,Cohen GN

更新日期：1984-05-01 00:00:00

abstract：:A loss-of-function mutation in the APC gene initiates colorectal carcinogenesis. Although the molecular mechanism of tumor initiation is complex, several modifier genes have been identified using mouse models, including the ApcMin mouse. Among the familial adenomatous polyposis mouse lines carrying a truncation mutati...

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

authors： Shibata H,Takano H,Ito M,Shioya H,Hirota M,Matsumoto H,Kakudo Y,Ishioka C,Akiyama T,Kanegae Y,Saito I,Noda T

更新日期：2007-11-13 00:00:00

abstract：:Expression of the two X-linked loci glucose-6-phosphate dehydrogenase (G6PD; EC 1.1.1.49) and hypoxanthine:guanine phosphoribosyltransferase (HGPRT; EC 2.4.2.8) was studied in single hair follicles of two females who were heterozygous for both of these genes (double heterozygotes). The coupling phase for these two loc...

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

authors： Goldstein JL,Marks JF,Gartler SM

更新日期：1971-07-01 00:00:00

abstract：:Two-dimensional gel electrophoresis of immunoprecipitated human HLA-DR antigens from cells expressing the HLA-DR4 haplotype shows distinct clustering of beta-chain patterns. Six unique electrophoretic variants were observed among 17 HLA-DR4 homozygous cell lines (HCL) analyzed. These patterns correlate precisely with ...

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

authors： Nepom BS,Nepom GT,Mickelson E,Antonelli P,Hansen JA

更新日期：1983-11-01 00:00:00

abstract：:A method is presented for starting from a very-low-energy high-dimensional conformation and obtaining a low-energy three-dimensional structure by gradual contraction of the dimensionality. The contraction in dimensionality is achieved by use of Cayley-Menger determinants, of which a simplified form is derived here. Pr...

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

authors： Purisima EO,Scheraga HA

更新日期：1986-05-01 00:00:00

abstract：:Olfactory receptor (OR) genes are of vital importance for animals to find food, identify mates, and avoid dangers. In mammals, the number of OR genes is large and varies extensively among different orders, whereas, in insects, the extent of interspecific variation appears to be small, although only a few species have ...

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

authors： Nozawa M,Nei M

更新日期：2007-04-24 00:00:00

abstract：:In contrast to observations in bacteria and fungi, frameshift mutations in bacteriophage T4 do not arise during genetic recombination. Nascent mutants, captured in the heterozygous condition, exhibit properties which indicate that the new lesions are located at the extreme tips of the chromosomes, and are segregated b...

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

authors： Lindstrom DM,Drake JW

更新日期：1970-03-01 00:00:00

abstract：:Although some important advances in the modeling of sorption and hygrothermal deformations of nanoporous materials such as hydrated cement paste, shale, coal, and some other rocks and soils have already been made, a comprehensive nanoporomechanics theory remains elusive. Here we strive to formulate it based on Gibb's ...

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

authors： Nguyen H,Rahimi-Aghdam S,Bažant ZP

更新日期：2020-02-18 00:00:00

abstract：:Forests and their soils contain the majority of the earth's terrestrial carbon stocks. Changes in patterns of tree growth can have a huge impact on atmospheric cycles, biogeochemical cycles, climate change, and biodiversity. Recent studies have shown increases in biomass across many forest types. This increase has bee...

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

authors： McMahon SM,Parker GG,Miller DR

更新日期：2010-02-23 00:00:00

abstract：:By combining the pairwise interactions between proteins, as predicted by the conserved co-occurrence of their genes in operons, we obtain protein interaction networks. Here we study the properties of such networks to identify functional modules: sets of proteins that together are involved in a biological process. The ...

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

authors： Snel B,Bork P,Huynen MA

更新日期：2002-04-30 00:00:00

abstract：:Very little is known about how animals discriminate pathogens from innocuous microbes. To address this question, we examined infection-response gene induction in the nematode Caenorhabditis elegans. We focused on genes that are induced in C. elegans by infection with the bacterial pathogen Pseudomonas aeruginosa, but ...

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

authors： Estes KA,Dunbar TL,Powell JR,Ausubel FM,Troemel ER

更新日期：2010-02-02 00:00:00

abstract：:We have carried out partial amino acid sequence analysis of a putative nuclear pore complex protein (nucleoporin) of rat that reacts with wheat germ agglutinin and with the polyspecific monoclonal antibody 414. Surprisingly, these partial amino acid sequence data revealed a high degree of similarity with the human CAN...

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

authors： Kraemer D,Wozniak RW,Blobel G,Radu A

更新日期：1994-02-15 00:00:00

abstract：:Phenylglyoxal is an arginine-specific reagent that inactivates creatine kinase (CK). Previous results suggest that modification of the dimeric enzyme at a single arginine residue per subunit causes complete inactivation accompanied by the loss of nucleotide binding; the actual site of modification was not identified. ...

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

authors： Wood TD,Guan Z,Borders CL Jr,Chen LH,Kenyon GL,McLafferty FW

更新日期：1998-03-31 00:00:00

abstract：:The DNA adducts formed during incubation of the hepatocarcinogen N-hydroxy-2-acetylaminofluorene with Salmonella typhimurium tester strain TA1538 were investigated to determine if the covalently bound products were identical to those adducts found in rat liver DNA and to establish the biological significance of the ad...

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

authors： Beranek DT,White GL,Heflich RH,Beland FA

更新日期：1982-09-01 00:00:00

abstract：:The mechanisms that regulate hematopoietic stem cell (HSC) fate decisions between proliferation and multilineage differentiation are unclear. Members of the Wnt family of ligands that activate the canonical Wnt signaling pathway, which utilizes beta-catenin to relay the signal, have been demonstrated to regulate HSC f...

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

authors： Nemeth MJ,Topol L,Anderson SM,Yang Y,Bodine DM

更新日期：2007-09-25 00:00:00

abstract：:Expressions are developed for weak single pair emission probability and strong emission average number of pairs. The water transparency cutoff is closely realized, showing that the fundamental time scale is even shorter. ...

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

authors： Schwinger J

更新日期：1993-05-15 00:00:00

abstract：:A cloned Bacillus subtilis gene (sprE) expressed only during the stationary growth phase is shown to encode the subtilisin E protease, an enzyme associated with sporulation. We have determined the DNA sequence of the sprE promoter region and the promoter-proximal half of the structural gene. The sprE gene codes for a ...

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

authors： Wong SL,Price CW,Goldfarb DS,Doi RH

更新日期：1984-02-01 00:00:00

abstract：:Denaturing gradient gel electrophoresis (DGGE) can be used to distinguish two DNA molecules that differ by as little as a single-base substitution. This method detects approximately 50% of all possible single-base changes in DNA fragments ranging from 50 to approximately 1000 base pairs. To increase the number of sing...

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

authors： Sheffield VC,Cox DR,Lerman LS,Myers RM

更新日期：1989-01-01 00:00:00

abstract：:Nucleosomes are the fundamental structural unit of chromatin. In addition to stabilizing the DNA polymer, nucleosomes are modified in ways that reflect and affect gene expression in their vicinity. It has long been assumed that nucleosomes can transmit memory of gene expression through their covalent posttranslational...

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

authors： Schlissel G,Rine J

更新日期：2019-10-08 00:00:00