Pronounced climatic variations in Alaska during the last two millennia.

abstract：:The 16S rRNA genes of Pyrobaculum aerophilum and Pyrobaculum islandicum were amplified by the polymerase chain reaction, and the resulting products were sequenced directly. The two organisms are closely related by this measure (over 98% similar). However, they differ in that the (lone) 16S rRNA gene of Pyrobaculum aer...

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

authors： Burggraf S,Larsen N,Woese CR,Stetter KO

更新日期：1993-03-15 00:00:00

abstract：:The crystal structure of a recombinant alphaEC domain from human fibrinogen-420 has been determined at a resolution of 2.1 A. The protein, which corresponds to the carboxyl domain of the alphaE chain, was expressed in and purified from Pichia pastoris cells. Felicitously, during crystallization an amino-terminal segme...

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

authors： Spraggon G,Applegate D,Everse SJ,Zhang JZ,Veerapandian L,Redman C,Doolittle RF,Grieninger G

更新日期：1998-08-04 00:00:00

abstract：:Experimental and computational simulations revealed that boron clusters, which favor planar (2D) structures up to 18 atoms, prefer 3D structures beginning at 20 atoms. Using global optimization methods, we found that the B20 neutral cluster has a double-ring tubular structure with a diameter of 5.2 A. For the B(-)20 a...

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

authors： Kiran B,Bulusu S,Zhai HJ,Yoo S,Zeng XC,Wang LS

更新日期：2005-01-25 00:00:00

abstract：:Concentrations and isotopic compositions of ethane and propane in cold, deeply buried sediments from the southeastern Pacific are best explained by microbial production of these gases in situ. Reduction of acetate to ethane provides one feasible mechanism. Propane is enriched in (13)C relative to ethane. The amount is...

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

authors： Hinrichs KU,Hayes JM,Bach W,Spivack AJ,Hmelo LR,Holm NG,Johnson CG,Sylva SP

更新日期：2006-10-03 00:00:00

abstract：:A high molecular weight protein (HMWP) with properties similar to those of both actin-binding protein (ABP) and filamin has been isolated from cultured baby hamster kidney (BHK-21) cells. The protein was present in an actomyosin-depleted sucrose extract of the cells and was eluted, upon gel chromatography on Sepharose...

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

authors： Schloss JA,Goldman RD

更新日期：1979-09-01 00:00:00

abstract：:Soret-excited resonance Raman spectroscopy yields direct information regarding the iron-carbon bonding interactions in the cyanomet and carbonmonoxy complexes of hemoglobin III from Chironomus thummi thummi (CTT III) in solution. By isotope exchange in cyanide (13CN-, C15N-, and 13C15N-) and carbon monoxide (13CO, C18...

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

authors： Yu NT,Benko B,Kerr EA,Gersonde K

更新日期：1984-08-01 00:00:00

abstract：:Nonsteroidal antiinflammatory drugs reduce the risk of colon cancer, possibly via cyclooxygenase (COX) inhibition. The growth factor-inducible COX-2, which is overexpressed in neoplastic colonic tissue, is an attractive target to mediate this effect. Herein we have exploited the ability of a human colon cancer cell li...

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

authors： Coffey RJ,Hawkey CJ,Damstrup L,Graves-Deal R,Daniel VC,Dempsey PJ,Chinery R,Kirkland SC,DuBois RN,Jetton TL,Morrow JD

更新日期：1997-01-21 00:00:00

abstract：:The cis-acting regulatory sequence of transcription from long terminal repeats (LTRs) of human T-cell leukemia virus type I and type II (HTLV-I and HTLV-II), which is essential for action of the virally encoded trans-acting transcriptional factor(s) designated pX(s), in HTLV-I and -II was identified. Deletion of most ...

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

authors： Shimotohno K,Takano M,Teruuchi T,Miwa M

更新日期：1986-11-01 00:00:00

abstract：:Glucocorticoids (GCs) are potent anti-inflammatory agents that block cytokine production. We investigated whether GCs also block cytokine signaling via the Janus kinase (Jak)-signal transducer and activator of transcription (STAT) pathway. Dexamethasone inhibited IL-2-induced DNA binding, tyrosine phosphorylation, and...

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

authors： Bianchi M,Meng C,Ivashkiv LB

更新日期：2000-08-15 00:00:00

abstract：:It has long been recognized that the renal proximal tubular epithelium of the hamster is a bona fide estrogen target tissue. The effect of estrogens on the growth of proximal tubule cell explants and dissociated single cells derived from these explant outgrowths has been studied in culture. Renal tubular cells were gr...

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

authors： Oberley TD,Lauchner LJ,Pugh TD,Gonzalez A,Goldfarb S,Li SA,Li JJ

更新日期：1989-03-01 00:00:00

abstract：:Neurofibrillary tangles are one of two lesions found in the brain of Alzheimer disease victims. With synthetic peptide fragments of human neurofilament NF-M17 (Glu-Glu-Lys-Gly-Lys-Ser-Pro- Val-Pro-Lys-Ser-Pro-Val-Glu-Glu-Lys-Gly, phosphorylated and unphosphorylated), CD studies were done to examine the effect of sodiu...

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

authors： Fasman GD,Moore CD

更新日期：1994-11-08 00:00:00

abstract：:The mosquito midgut plays a central role in the sporogonic development of malaria parasites. We have found that polyclonal sera, produced against mosquito midguts, blocked the passage of Plasmodium falciparum ookinetes across the midgut, leading to a significant reduction of infections in mosquitoes. Anti-midgut mAbs ...

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

authors： Lal AA,Patterson PS,Sacci JB,Vaughan JA,Paul C,Collins WE,Wirtz RA,Azad AF

更新日期：2001-04-24 00:00:00

abstract：:The DnaE intein in Synechocystis sp. strain PCC6803 is the first and only naturally split intein that has been identified so far. It is capable of catalyzing a protein trans-splicing mechanism to assemble a mature protein from two separate precursors. Therefore, it is a powerful tool for protein modification and engin...

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

authors： Yang J,Fox GC Jr,Henry-Smith TV

更新日期：2003-03-18 00:00:00

abstract：:Myosin V, a double-headed molecular motor, transports organelles within cells by walking processively along actin, a process that requires coordination between the heads. To understand the mechanism underlying this coordination, processive runs of single myosin V molecules were perturbed by varying nucleotide content....

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

authors： Baker JE,Krementsova EB,Kennedy GG,Armstrong A,Trybus KM,Warshaw DM

更新日期：2004-04-13 00:00:00

abstract：:Immunoglobulin heavy-chain variable region (TH) gene segments located closest to the joining (JH) gene segments are preferentially rearranged during ontogeny, indicating that chromosomal position influences the frequency of rearrangement. In addition, certain VH gene segments are repeatedly rearranged, suggesting that...

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

authors： Lawler AM,Kearney JF,Kuehl M,Gearhart PJ

更新日期：1989-09-01 00:00:00

abstract：:We present the use of our recently described multiple-loci polymorphic DNA markers ("alumorphs") for linkage mapping of the human genome. By using the polymerase chain reaction (PCR) with an Alu-specific primer we could reveal, in a single experiment, up to 20 genomic polymorphisms seen as the presence or absence of a...

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

authors： Zietkiewicz E,Labuda M,Sinnett D,Glorieux FH,Labuda D

更新日期：1992-09-15 00:00:00

abstract：:High-throughput screening (HTS) of chemical compounds to identify modulators of molecular targets is a mainstay of pharmaceutical development. Increasingly, HTS is being used to identify chemical probes of gene, pathway, and cell functions, with the ultimate goal of comprehensively delineating relationships between ch...

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

authors： Inglese J,Auld DS,Jadhav A,Johnson RL,Simeonov A,Yasgar A,Zheng W,Austin CP

更新日期：2006-08-01 00:00:00

abstract：:The interleukin 2 (IL-2) receptor (IL-2R) is a multisubunit receptor that includes three major IL-2 binding subunits, the IL-2R alpha, beta, and gamma chains. We have detected and analyzed cooperative interactions between the IL-2R alpha and beta chains (IL-2R alpha and IL-2R beta, respectively) in COS cells transfect...

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

authors： Roessler E,Grant A,Ju G,Tsudo M,Sugamura K,Waldmann TA

更新日期：1994-04-12 00:00:00

abstract：:The marine cyanobacterium Trichodesmium is ubiquitous in tropical and subtropical seas and is an important contributor to global N and C cycling. We sought to characterize metabolic uptake patterns in individual Trichodesmium IMS-101 cells by quantitatively imaging (13)C and (15)N uptake with high-resolution secondary...

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

authors： Finzi-Hart JA,Pett-Ridge J,Weber PK,Popa R,Fallon SJ,Gunderson T,Hutcheon ID,Nealson KH,Capone DG

更新日期：2009-04-14 00:00:00

abstract：:Glucocorticoid and cyclic AMP increase tyrosine hydroxylase (TH) activity and mRNA levels in pheochromocytoma cultures. The transcriptional activity of the TH gene, as measured by nuclear run-on assay, is also increased when cultures are treated with the synthetic glucocorticoid dexamethasone or agents that increase i...

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

authors： Lewis EJ,Harrington CA,Chikaraishi DM

更新日期：1987-06-01 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：:Reducible compounds that participate in crosslinking were analyzed in hydroxylysine-deficient collagens of patients with a heritable disorder of connective tissue. After treatment with [(3)H]sodium borohydride, new compounds, as well as a totally different pattern of tritiated compounds, were found in hydroxylysine-de...

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

authors： Eyre DR,Glimcher MJ

更新日期：1972-09-01 00:00:00

abstract：:The regulation of glycogen metabolism is critical for the maintenance of glucose and energy homeostasis in mammals. Glycogen synthase, the enzyme responsible for glycogen production, is regulated by multisite phosphorylation in yeast and mammals. We have previously identified PAS kinase as a physiological regulator of...

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

authors： Wilson WA,Skurat AV,Probst B,de Paoli-Roach A,Roach PJ,Rutter J

更新日期：2005-11-15 00:00:00

abstract：:mRNA for the large subunit (LS) of ribulose-1,5-bisphosphate carboxylase [3-phospho-D-glycerate carboxylase (dimerizing), EC 4.1.1.39] of Zea mays is complementary to an uninterrupted 1600-base-pair-long chloroplast DNA sequence that has been mapped precisely within the 4350-base-pair-long chloroplast DNA fragment Bam...

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

authors： Link G,Bogorad L

更新日期：1980-04-01 00:00:00

abstract：:Adult stem cells represent unique populations of undifferentiated cells with self-renewal capacity. In many tissues, stem cells divide less often than their progeny. It has been widely speculated, but largely untested, that their undifferentiated and quiescent state may make stem cells more efficient as donors for clo...

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

authors： Li J,Greco V,Guasch G,Fuchs E,Mombaerts P

更新日期：2007-02-20 00:00:00

abstract：:The N,N'-diacetyllactosediamine (lacdiNAc) pathway of complex-type oligosaccharide synthesis is controlled by a UDP-GalNAc:GlcNAc beta-R beta 1-->4-N-acetylgalac-tesaminyltransferase (beta 4-GalNAcT) that acts analogously to the common UDP-Gal:GlcNAc beta-R beta 1-->4-galactosyltransferase (beta 4-GalT). LacdiNAc-base...

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

authors： Neeleman AP,van de Eijnden DH

更新日期：1996-09-17 00:00:00

abstract：:Discrete state models are a common tool of modeling in many areas. E.g., Markov state models as a particular representative of this model family became one of the major instruments for analysis and understanding of processes in molecular dynamics (MD). Here we extend the scope of discrete state models to the case of s...

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

authors： Gerber S,Horenko I

更新日期：2014-10-14 00:00:00

abstract：:Prions are thought to consist mainly or entirely of misfolded PrP, a constitutively expressed host protein. Prions associated with the same PrP sequence may occur in the form of different strains; the strain phenotype is believed to be encoded by the conformation of the PrP. Some cell lines can be persistently infecte...

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

authors： Mahal SP,Baker CA,Demczyk CA,Smith EW,Julius C,Weissmann C

更新日期：2007-12-26 00:00:00

abstract：:In this study we compared the cellular concentrations and stability of the mRNA transcribed from the aprE (subtilisin) gene (a gene preferentially expressed in stationary growth phase) with those of a vegetative mRNA, succinate dehydrogenase (SDH) mRNA. The subtilisin transcript was shown to be at least 3 times more s...

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

authors： Resnekov O,Rutberg L,von Gabain A

更新日期：1990-11-01 00:00:00

abstract：:Highly expanded Cretaceous-Paleogene (K-Pg) boundary section from the Chicxulub peak ring, recovered by International Ocean Discovery Program (IODP)-International Continental Scientific Drilling Program (ICDP) Expedition 364, provides an unprecedented window into the immediate aftermath of the impact. Site M0077 inclu...

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

authors： Gulick SPS,Bralower TJ,Ormö J,Hall B,Grice K,Schaefer B,Lyons S,Freeman KH,Morgan JV,Artemieva N,Kaskes P,de Graaff SJ,Whalen MT,Collins GS,Tikoo SM,Verhagen C,Christeson GL,Claeys P,Coolen MJL,Goderis S,Goto K,

更新日期：2019-09-24 00:00:00