Cell differentiation in Dictyostelium under submerged conditions.

abstract：:Oscillatory activity is widespread in dynamic neuronal networks. The main paradigm for the origin of periodicity consists of specialized pacemaking elements that synchronize and drive the rest of the network; however, other models exist. Here, we studied the spontaneous emergence of synchronized periodic bursting in a...

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

authors： Penn Y,Segal M,Moses E

更新日期：2016-03-22 00:00:00

abstract：:Noniridescent coloration by the spongy keratin in parrot feather barbs has fascinated scientists. Nonetheless, its ultimate origin remains as yet unanswered, and a quantitative structural and optical description is still lacking. Here we report on structural and optical characterizations and numerical simulations of t...

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

authors： Yin H,Dong B,Liu X,Zhan T,Shi L,Zi J,Yablonovitch E

更新日期：2012-07-03 00:00:00

abstract：:To explore the basis for the template specificities of the bacteriophage T3 and T7 RNA polymerases (EC 2.7.7.6), we determined the nucleotide sequences of six promoters recognized by the T3 RNA polymerase and compared them with the previously determined promoter sequences recognized by the bacteriophage T7 RNA polymer...

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

authors： Bailey JN,Klement JF,McAllister WT

更新日期：1983-05-01 00:00:00

abstract：:Susceptibility of activated T cells to apoptosis must be tightly regulated to ensure sufficient T cell progeny for an effective response, while allowing a rapid depletion of them at the end of the immune response. We show here that a previously isolated, NF-kappa B/rel target gene IEX-1 (Immediate Early response gene ...

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

authors： Zhang Y,Schlossman SF,Edwards RA,Ou CN,Gu J,Wu MX

更新日期：2002-01-22 00:00:00

abstract：:2-Acetylpyridine 5-[(dimethylamino)thiocarbonyl]thiocarbonohydrazone (A1110U) was found to be a potent inactivator of the ribonucleotide reductases (EC 1.17.4.1) encoded by herpes simplex virus types 1 and 2 and by varicella-zoster virus and to be a weaker inactivator of human ribonucleotide reductase. It also markedl...

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

authors： Spector T,Harrington JA,Morrison RW Jr,Lambe CU,Nelson DJ,Averett DR,Biron K,Furman PA

更新日期：1989-02-01 00:00:00

abstract：:The eIF2alpha kinases are a family of evolutionarily conserved serine/threonine kinases that regulate stress-induced translational arrest. Here, we demonstrate that the yeast eIF2alpha kinase, GCN2, the target phosphorylation site of Gcn2p, Ser-51 of eIF2alpha, and the eIF2alpha-regulated transcriptional transactivato...

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

authors： Tallóczy Z,Jiang W,Virgin HW 4th,Leib DA,Scheuner D,Kaufman RJ,Eskelinen EL,Levine B

更新日期：2002-01-08 00:00:00

abstract：:The transmission of complexity during DNA replication has been investigated to clarify the significance of this molecular property in a deterministic process. Complexity was equated with the amount of randomness within an ordered molecular structure and measured by the entropy of a posteriori probabilities for discret...

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

authors： Davis BK

更新日期：1979-05-01 00:00:00

abstract：:The mechanism of proton transfer from the bulk into the membrane protein interior was studied. The light-induced reduction of a bound ubiquinone molecule Q(B) by the photosynthetic reaction center is accompanied by proton trapping. We used kinetic spectroscopy to measure (i) the electron transfer to Q(B) (at 450 nm), ...

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

authors： Gopta OA,Cherepanov DA,Junge W,Mulkidjanian AY

更新日期：1999-11-09 00:00:00

abstract：:Although in decline after successful anti-HIV therapy, B-cell lymphomas are still elevated in HIV-1-seropositive (HIV+) persons, and the mechanisms are obscure. The HIV-1 matrix protein p17 persists in germinal centers long after HIV-1 drug suppression, and some p17 variants (vp17s) activate Akt signaling and promote ...

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

authors： Dolcetti R,Giagulli C,He W,Selleri M,Caccuri F,Eyzaguirre LM,Mazzuca P,Corbellini S,Campilongo F,Marsico S,Giombini E,Muraro E,Rozera G,De Paoli P,Carbone A,Capobianchi MR,Ippolito G,Fiorentini S,Blattner WA,Lu W,

更新日期：2015-11-17 00:00:00

abstract：:Transgenic pigs were generated that produced human protein C in their milk at up to 1 g/liter. The gene construct was a fusion gene consisting of the cDNA for human protein C inserted into the first exon of the mouse whey acidic protein gene. These results demonstrate that the mouse whey acidic protein gene contains r...

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

authors： Velander WH,Johnson JL,Page RL,Russell CG,Subramanian A,Wilkins TD,Gwazdauskas FC,Pittius C,Drohan WN

更新日期：1992-12-15 00:00:00

abstract：:A (Mg(2+) + Ca(2+))ATPase (ATP phosphohydrolase, EC 3.6.1.3) has been purified from sarcoplasmic reticulum using a single step centrifugation procedure. The preparation is >95% pure by weight and contains only 25-30% of the lipid associated with the enzyme in native sarcoplasmic reticulum. The purified enzyme is unabl...

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

authors： Warren GB,Toon PA,Birdsall NJ,Lee AG,Metcalfe JC

更新日期：1974-03-01 00:00:00

abstract：:To test directly whether fibrin(ogen) is a key binding site for apolipoprotein(a) [apo(a)] in vessel walls, apo(a) transgenic mice and fibrinogen knockout mice were crossed to generate fibrin(ogen)-deficient apo(a) transgenic mice and control mice. In the vessel wall of apo(a) transgenic mice, fibrin(ogen) deposition ...

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

authors： Lou XJ,Boonmark NW,Horrigan FT,Degen JL,Lawn RM

更新日期：1998-10-13 00:00:00

abstract：:Agricultural foods and technologies are thought to have eased the mechanical demands of diet-how often or how hard one had to chew-in human populations worldwide. Some evidence suggests correspondingly worldwide changes in skull shape and form across the agricultural transition, although these changes have proved diff...

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

authors： Katz DC,Grote MN,Weaver TD

更新日期：2017-08-22 00:00:00

abstract：:Recent technical advances allow detection of several hundred volatile organic compounds (VOCs) in human exhaled air, many of which reflect unidentified endogenous pathways. Our group has previously estimated plasma glucose levels in healthy adults during a standard oral glucose tolerance test via exhaled VOC analysis....

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

authors： Novak BJ,Blake DR,Meinardi S,Rowland FS,Pontello A,Cooper DM,Galassetti PR

更新日期：2007-10-02 00:00:00

abstract：:There exists a properly embedded minimal surface of genus one with a single end asymptotic to the end of the helicoid. This genus-one helicoid is constructed as the limit of a continuous one-parameter family of screw-motion invariant minimal surfaces, also asymptotic to the helicoid, that have genus equal to one in th...

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

authors： Weber M,Hoffman D,Wolf M

更新日期：2005-11-15 00:00:00

abstract：:Previous studies have shown that the effect of language on categorical perception of color is stronger when stimuli are presented in the right visual field than in the left. To examine whether this lateralized effect occurs preattentively at an early stage of processing, we monitored the visual mismatch negativity, wh...

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

authors： Mo L,Xu G,Kay P,Tan LH

更新日期：2011-08-23 00:00:00

abstract：:Improper function of voltage-gated sodium channels (NaVs), obligatory membrane proteins for bioelectrical signaling, has been linked to a number of human pathologies. Small-molecule agents that target NaVs hold considerable promise for treatment of chronic disease. Absent a comprehensive understanding of channel struc...

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

authors： Thomas-Tran R,Du Bois J

更新日期：2016-05-24 00:00:00

abstract：:Supernumerary B chromosomes are optional additions to the basic set of A chromosomes, and occur in all eukaryotic groups. They differ from the basic complement in morphology, pairing behavior, and inheritance and are not required for normal growth and development. The current view is that B chromosomes are parasitic e...

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

authors： Martis MM,Klemme S,Banaei-Moghaddam AM,Blattner FR,Macas J,Schmutzer T,Scholz U,Gundlach H,Wicker T,Šimková H,Novák P,Neumann P,Kubaláková M,Bauer E,Haseneyer G,Fuchs J,Doležel J,Stein N,Mayer KF,Houben A

更新日期：2012-08-14 00:00:00

abstract：:We have used electron microscopy to examine freshly isolated Salmonella typhimurium and Escherichia coli basal flagellar fragments, purified without resort to extremes of pH or ionic strength. Such fragments contain the large bell-like basal structures visualized recently in freeze-substituted or fixed preparations. W...

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

authors： Khan IH,Reese TS,Khan S

更新日期：1992-07-01 00:00:00

abstract：:Tyr-SV40E transgenic mice are susceptible to melanoma due to simian virus 40 oncogenic sequences specifically expressed in pigment cells. Skin melanomas form relatively late. Therefore, melanocyte cell lines have been established from very young transgenic animals, when they showed no skin lesions, so that the spontan...

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

authors： Larue L,Dougherty N,Mintz B

更新日期：1992-10-15 00:00:00

abstract：:The requirement for protein synthesis in the mechanism of a circadian pacemaker was investigated by using inhibitors of protein synthesis. Continuous treatment of the ocular circadian pacemaker of the mollusc Bulla gouldiana with anisomycin or cycloheximide substantially lengthened (up to 39 and 52 hr, respectively) t...

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

authors： Khalsa SB,Whitmore D,Block GD

更新日期：1992-11-15 00:00:00

abstract：:Regulated exocytosis requires tight coupling of the membrane fusion machinery to a triggering signal and a fast response time. Complexins are part of this regulation and, together with synaptotagmins, control calcium-dependent exocytosis. Stimulatory and inhibitory functions have been reported for complexins. To test ...

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

authors： Malsam J,Seiler F,Schollmeier Y,Rusu P,Krause JM,Söllner TH

更新日期：2009-02-10 00:00:00

abstract：:The Late Heavy Bombardment (LHB), a hypothesized impact spike at ∼3.9 Ga, is one of the major scientific concepts to emerge from Apollo-era lunar exploration. A significant portion of the evidence for the existence of the LHB comes from histograms of (40)Ar/(39)Ar "plateau" ages (i.e., regions selected on the basis of...

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

authors： Boehnke P,Harrison TM

更新日期：2016-09-27 00:00:00

abstract：:Most studies on the ability of insect populations to transmit pathogens consider only constant temperatures and do not account for realistic daily temperature fluctuations that can impact vector-pathogen interactions. Here, we show that diurnal temperature range (DTR) affects two important parameters underlying dengue...

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

authors： Lambrechts L,Paaijmans KP,Fansiri T,Carrington LB,Kramer LD,Thomas MB,Scott TW

更新日期：2011-05-03 00:00:00

abstract：:We explore the interactions of CYT-19, a DExD/H-box protein that functions in folding of group I RNAs, with a well characterized misfolded species of the Tetrahymena ribozyme. Consistent with its function, CYT-19 accelerates refolding of the misfolded RNA to its native state. Unexpectedly, CYT-19 performs another reac...

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

authors： Tijerina P,Bhaskaran H,Russell R

更新日期：2006-11-07 00:00:00

abstract：:Within the basal ganglia, acetylcholine and dopamine play a central role in the extrapyramidal control of motor function. The physiologic effects of these neurotransmitters are mediated by a diversity of receptor subtypes, several of which have now been cloned. Muscarinic acetylcholine receptors are encoded by five ge...

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

authors： Weiner DM,Levey AI,Brann MR

更新日期：1990-09-01 00:00:00

abstract：:Are judicial rulings based solely on laws and facts? Legal formalism holds that judges apply legal reasons to the facts of a case in a rational, mechanical, and deliberative manner. In contrast, legal realists argue that the rational application of legal reasons does not sufficiently explain the decisions of judges an...

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

authors： Danziger S,Levav J,Avnaim-Pesso L

更新日期：2011-04-26 00:00:00

abstract：:During the late summer to fall of 1987, Caribbean reef corals experienced an intense and widespread discoloration event described as bleaching. Contrary to initial predictions, most bleached corals did not die. However, energy input from zooxanthellae decreased, as estimated from: (i) delta(13)C values, a measure of t...

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

authors： Porter JW,Fitt WK,Spero HJ,Rogers CS,White MW

更新日期：1989-12-01 00:00:00

abstract：:Using an antiserum raised against a synthetic C-terminal peptide of porcine pancreastatin, we detected pancreastatin-like immunoreactivity (PLI) in human pancreatic islets, adrenal medulla, and endocrine tumors. From a carcinoid liver metastasis, human PLI was extracted and purified by HPLC. Two C-terminally amidated ...

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

authors： Schmidt WE,Siegel EG,Kratzin H,Creutzfeldt W

更新日期：1988-11-01 00:00:00

abstract：:Free gangliosides bind fibroblast growth factor 2 (FGF2), thus preventing cell interaction and biological activity of the growth factor in endothelial cells. Here we investigated the role of cell-associated gangliosides in mediating the biological activity of FGF2. Treatment of endothelial cells of different origin wi...

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

authors： Rusnati M,Urbinati C,Tanghetti E,Dell'Era P,Lortat-Jacob H,Presta M

更新日期：2002-04-02 00:00:00