Climatic change and wetland desiccation cause amphibian decline in Yellowstone National Park.

abstract：:With decreasing temperature, liquids generally freeze into a solid state, losing entropy in the process. However, exceptions to this trend exist, such as quantum liquids, which may remain unfrozen down to absolute zero owing to strong quantum entanglement effects that stabilize a disordered state with zero entropy. Ex...

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

authors： Katayama N,Kimura K,Han Y,Nasu J,Drichko N,Nakanishi Y,Halim M,Ishiguro Y,Satake R,Nishibori E,Yoshizawa M,Nakano T,Nozue Y,Wakabayashi Y,Ishihara S,Hagiwara M,Sawa H,Nakatsuji S

更新日期：2015-07-28 00:00:00

abstract：:Polycomb-group (Pc-G) proteins ensure late maintenance of transcriptional repression outside the expression domain of target genes in flies and vertebrates. They act in complexes, presumably by modulating chromatin structure. In Drosophila, they have been found to be associated with transcriptionally inactive loci but...

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

authors： d Graaff W,Tomotsune D,Oosterveen T,Takihara Y,Koseki H,Deschamps J

更新日期：2003-11-11 00:00:00

abstract：:The molecular weight of the major glycoprotein from the human erythrocyte membrane is 29,000, of which 55% is carbohydrate and 45% is protein. The binding of sodium dodecyl sulfate to this glycoprotein is anomalous when compared to water soluble proteins and leads to migration rates in sodium dodecyl sulfate-polyacryl...

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

authors： Grefrath SP,Reynolds JA

更新日期：1974-10-01 00:00:00

abstract：:The substrate specificity of the catalytic subunit of rabbit skeletal muscle 3': 5'-cyclic AMP-dependent protein kinase (EC 2.7.1.37; ATP: protein phosphotransferase) has been studied using the synthetic peptide Arg-Gly-Tyr-Ser-Leu-Gly corresponding to the sequence around serine 24, a phosphorylation site in reduced, ...

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

authors： Kemp BE,Benjamini E,Krebs EG

更新日期：1976-04-01 00:00:00

abstract：:Expression of glucokinase in hepatocytes and pancreatic 6-cells is of major physiologic importance to mammalian glucose homeostasis. Liver glucokinase catalyzes the first committed step in the disposal of glucose, and beta-cell glucokinase catalyzes a rate-limiting step required for glucose-regulated insulin release. ...

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

authors： Heimberg H,De Vos A,Moens K,Quartier E,Bouwens L,Pipeleers D,Van Schaftingen E,Madsen O,Schuit F

更新日期：1996-07-09 00:00:00

abstract：:We developed a method for rapidly generating thermostable enzyme variants. Our strategy is to introduce the gene coding for a given enzyme from a mesophilic organism into a thermophile, Bacillus stearothermophilus. Variants that retain the enzymatic activity at the higher growth temperatures of the thermophile are the...

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

authors： Liao H,McKenzie T,Hageman R

更新日期：1986-02-01 00:00:00

abstract：:We have synthesized pulmonary surfactant apoprotein SP-B peptides by solid-phase chemistry and demonstrated their ability to enhance the surface-active properties of synthetic lipid mixtures. The synthetic peptides were reactive with antiserum generated against the native bovine surfactant peptide. Both peptides confe...

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

authors： Sarin VK,Gupta S,Leung TK,Taylor VE,Ohning BL,Whitsett JA,Fox JL

更新日期：1990-04-01 00:00:00

abstract：:The effects of calcium ion on the Na+ activation gate were studied in squid giant axons. Saxitoxin (STX) was used to block ion entry into Na+ channels without hindering access to the membrane surface, making it possible to distinguish surface effects of calcium from pore-occupancy effects. In the presence of STX, gati...

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

authors： Armstrong CM

更新日期：1999-03-30 00:00:00

abstract：:To enable discovery of serum antibodies indicative of disease and simultaneously develop reagents suitable for diagnosis, in vitro directed evolution was applied to identify consensus peptides recognized by patients' serum antibodies. Bacterial cell-displayed peptide libraries were quantitatively screened for binders ...

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

authors： Ballew JT,Murray JA,Collin P,Mäki M,Kagnoff MF,Kaukinen K,Daugherty PS

更新日期：2013-11-26 00:00:00

abstract：:In sexual populations, selection operates neither on the whole genome, which is repeatedly taken apart and reassembled by recombination, nor on individual alleles that are tightly linked to the chromosomal neighborhood. The resulting interference between linked alleles reduces the efficiency of selection and distorts ...

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

authors： Neher RA,Kessinger TA,Shraiman BI

更新日期：2013-09-24 00:00:00

abstract：:Selenophosphate, an activated form of selenium that can serve as a selenium donor, is generated by the selD gene product, selenophosphate synthetase (SPS). Selenophosphate is required by several bacteria and by mammals for the specific synthesis of Secys-tRNA, the precursor of selenocysteine in selenoenzymes. Although...

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

authors： Ogasawara Y,Lacourciere GM,Ishii K,Stadtman TC

更新日期：2005-01-25 00:00:00

abstract：:Mutations in fibroblast growth factor receptor 2 (FGFR2) and its ligand, FGF10, are known to cause lacrimo-auriculo-dento-digital (LADD) syndrome. Multiple gain-of-function mutations in FGF receptors have been implicated in a variety of severe skeletal disorders and in many cancers. We aimed to elucidate the mechanism...

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

authors： Lew ED,Bae JH,Rohmann E,Wollnik B,Schlessinger J

更新日期：2007-12-11 00:00:00

abstract：:The spleen is the lymphoid organ that induces immune responses toward blood-borne pathogens. Specialized macrophages in the splenic marginal zone are strategically positioned to phagocytose pathogens and cell debris, but are not known to play a role in the activation of T-cell responses. Here we demonstrate that splen...

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

authors： Backer R,Schwandt T,Greuter M,Oosting M,Jüngerkes F,Tüting T,Boon L,O'Toole T,Kraal G,Limmer A,den Haan JM

更新日期：2010-01-05 00:00:00

abstract：:Legionella pneumophila is an intracellular parasite of freshwater protozoa and human macrophages. Recent studies determined that the macrophage infectivity potentiator (Mip) surface protein, a prokaryotic homolog of the FK506-binding proteins, is required for optimal infection of macrophages. To determine whether Mip ...

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

authors： Cianciotto NP,Fields BS

更新日期：1992-06-01 00:00:00

abstract：:A rapid, simple, and quantitative filter-binding assay using glass fiber filters has been developed to detect the convalent adenovirus DNA-terminal protein complex. The assay is unusually sensitive because binding of protein-free DNA generally is less than 0.1%. Binding of the adenovirus complex to filters is mediated...

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

authors： Coombs DH,Pearson GD

更新日期：1978-11-01 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：:Vascular endothelial growth factor C (VEGF-C) recently has been described to be a relatively specific growth factor for the lymphatic vascular system. Here we report that ectopic application of recombinant VEGF-C also has potent angiogenic effects in vivo. VEGF-C is sufficiently potent to stimulate neovascularization ...

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

authors： Cao Y,Linden P,Farnebo J,Cao R,Eriksson A,Kumar V,Qi JH,Claesson-Welsh L,Alitalo K

更新日期：1998-11-24 00:00:00

abstract：:In the presence of phenylalanine, GTP cyclohydrolase I feedback regulatory protein (GFRP) forms a stimulatory 360-kDa complex with GTP cyclohydrolase I (GTPCHI), which is the rate-limiting enzyme in the biosynthesis of tetrahydrobiopterin. The crystal structure of the stimulatory complex reveals that the GTPCHI decame...

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

authors： Maita N,Okada K,Hatakeyama K,Hakoshima T

更新日期：2002-02-05 00:00:00

abstract：:Antibodies may bind to bacterial pathogens or their toxins to control infections, and their effector activity is mediated through the recruitment of complement component C1q or the engagement with Fcγ receptors (FcγRs). For bacterial pathogens that rely on a single toxin to cause disease, immunity correlates with toxi...

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

authors： Chen X,Shi M,Tong X,Kim HK,Wang LX,Schneewind O,Missiakas D

更新日期：2020-09-15 00:00:00

abstract：:T cells that have been immunized to express optimal levels of contact hypersensitivity upon adoptive transfer to normal animals can be inhibited from doing so by incubating them with an antigen-specific T suppressor factor. This factor is composed of at least two subunits which come from cells expressing different Ly ...

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

authors： Ptak W,Rosenstein RW,Gershon RK

更新日期：1982-04-01 00:00:00

abstract：:These studies sought to determine if neurons in the estrogen receptor-alpha knockout (ERalphaKO) mouse brain concentrated 16alpha-[125I]iodo-11beta-methoxy-17beta-estradiol (125I-estrogen), and if so, whether estrogen binding augmented the expression of progesterone receptor (PR) mRNA. Mice were injected with 125I-est...

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

authors： Shughrue PJ,Lubahn DB,Negro-Vilar A,Korach KS,Merchenthaler I

更新日期：1997-09-30 00:00:00

abstract：:The supernatant fluid (conditioned medium) of cultured human vascular endothelial cells inhibits activation of Hageman factor (factor XII), whether by ellagic acid, bovine brain sulfatides, or bismuth subgallate; inhibition appears to be a property of one or more proteins in the culture supernates. This phenomenon may...

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

authors： Ratnoff OD,Everson B,Embury P,Ziats NP,Anderson JM,Emanuelson MM,Malemud CJ

更新日期：1991-12-01 00:00:00

abstract：:We have studied hepatic uptake of chylomicron retinyl ester. Chylomicrons were obtained from intestinal lymph of rats that were given retinol in groundnut oil by intraduodenal injection. When lymph was injected intravenously into normal rats, the radioactivity was cleared from blood with t1/2 approximately equal to 10...

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

authors： Blomhoff R,Helgerud P,Rasmussen M,Berg T,Norum KR

更新日期：1982-12-01 00:00:00

abstract：:Bordetella pertussis secretes a calmodulin-activated adenylate cyclase toxin, CyaA, that is able to deliver its N-terminal catalytic domain (400-aa residues) into the cytosol of eukaryotic target cells, directly through the cytoplasmic membrane. We have previously shown that CyaA can be used as a vehicle to deliver T ...

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

authors： Karimova G,Fayolle C,Gmira S,Ullmann A,Leclerc C,Ladant D

更新日期：1998-10-13 00:00:00

abstract：:The tips of the digits of some mammals, including human infants and mice, are capable of complete regeneration after injury. This process is reliant on the presence of the overlaying nail organ and is mediated by a proliferative blastema. Epithelial Wnt/β-catenin signaling has been shown to be necessary for mouse digi...

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

authors： Lehoczky JA,Tabin CJ

更新日期：2015-10-27 00:00:00

abstract：:This paper provides transcendental and algebraic framework for the classification of identities expressing pi and other logarithms of algebraic numbers as rapidly convergent generalized hypergeometric series in rational parameters. Algebraic and arithmetic relations between values of p+1Fp hypergeometric functions and...

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

authors： Chudnovsky DV,Chudnovsky GV

更新日期：1998-03-17 00:00:00

abstract：:Oriented cell division is critical for cell fate specification, tissue organization, and tissue homeostasis, and relies on proper orientation of the mitotic spindle. The molecular mechanisms underlying the regulation of spindle orientation remain largely unknown. Herein, we identify a critical role for cylindromatosis...

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

authors： Yang Y,Liu M,Li D,Ran J,Gao J,Suo S,Sun SC,Zhou J

更新日期：2014-02-11 00:00:00

abstract：:There is currently no consensus on the importance of climate change in Mesoamerican prehistory. Some invoke drought as a causal factor in major cultural transitions, including the abandonment of many sites at 900 CE, while others conclude that cultural factors were more important. This lack of agreement reflects the f...

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

authors： Bhattacharya T,Byrne R,Böhnel H,Wogau K,Kienel U,Ingram BL,Zimmerman S

更新日期：2015-02-10 00:00:00

abstract：:Whole-cell DNA preparations isolated from SC-1 cells chronically infected with N- or B-tropic murine leukemia viruses (MuLV) were tested for infectious activity in an Fv-1n (NIH-3T3) and two Fv-Ib (C57BL/6 and SV-A31) cell cultures. Efficiency of transfection for all DNAs was better in the NIH-3T3 cells than in C57BL/...

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

authors： Hsu IC,Yang WK,Tennant RW,Brown A

更新日期：1978-03-01 00:00:00

abstract：:Gene delivery to the central nervous system is central to the development of gene therapy for neurological diseases. We developed a baculovirus-derived vector, the Bac-CMV-GFP vector, containing a reporter gene encoding for the green fluorescent protein (GFP) under the control of the cytomegalovirus (CMV) promoter. Tw...

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

authors： Sarkis C,Serguera C,Petres S,Buchet D,Ridet JL,Edelman L,Mallet J

更新日期：2000-12-19 00:00:00