Resources and energetics determined dinosaur maximal size.

abstract：:The biological basis underlying differentiation of naive (NAI) T cells into effector (EFFE) and memory (MEM) cells is incompletely understood. Furthermore, whether NAI T cells serially differentiate into EFFE and then MEM cells (linear differentiation) or whether they concurrently differentiate into either EFFE or MEM...

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

authors： Holmes S,He M,Xu T,Lee PP

更新日期：2005-04-12 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：:The activity of leukotriene A4 (LTA4) synthase in crude human leukocyte homogenates was found to have a similar requirement for Ca2+ and ATP as had been noted previously for 5-lipoxygenase activity. Purification of the 5-lipoxygenase using ammonium sulfate fractionation, AcA 44 gel-filtration chromatography, and HPLC ...

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

authors： Rouzer CA,Matsumoto T,Samuelsson B

更新日期：1986-02-01 00:00:00

abstract：:In myocardial ischemia, adrenergic nerves release excessive amounts of norepinephrine (NE), causing dysfunction and arrhythmias. With anoxia and the concomitant ATP depletion, vesicular storage of NE is impaired, resulting in accumulation of free NE in the axoplasm of sympathetic nerves. Intraneuronal acidosis activat...

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

authors： Silver RB,Mackins CJ,Smith NC,Koritchneva IL,Lefkowitz K,Lovenberg TW,Levi R

更新日期：2001-02-27 00:00:00

abstract：:With Manduca sexta as a model system, we analyzed how natural odor mixtures that are most effective in eliciting flight and foraging behaviors are encoded in the primary olfactory center in the brain, the antennal lobe. We used gas chromatography coupled with multiunit neural-ensemble recording to identify key odorant...

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

authors： Riffell JA,Lei H,Hildebrand JG

更新日期：2009-11-17 00:00:00

abstract：:Ehrlich and Raven formally introduced the concept of stepwise coevolution using butterfly and angiosperm interactions in an attempt to account for the impressive biological diversity of these groups. However, many biologists currently envision butterflies evolving 50 to 30 million years (Myr) after the major angiosper...

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

authors： Wheat CW,Vogel H,Wittstock U,Braby MF,Underwood D,Mitchell-Olds T

更新日期：2007-12-18 00:00:00

abstract：:Agrobacterium tumefaciens harboring the tumor-inducing Ti plasmid incites crown gall tumor on dicotyledonous species. Upon infection of these plants, Ti plasmid DNA sequence is stably transferred (T-DNA) by unknown mechanisms to plant cells to be integrated into nuclear DNA. The T-DNA processing and transfer require t...

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

authors： Usami S,Okamoto S,Takebe I,Machida Y

更新日期：1988-06-01 00:00:00

abstract：:We have synthesized 175-nucleotide-long probes for the DNA of human histocompatibility antigens HLA-DR alpha and beta by extending on poly(A)+ mRNA from B-cell lines with short synthetic deoxyribonucleotide primers complementary to the predicted nucleotide sequence of the NH2 terminus of both polypeptides. The synthes...

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

authors： Das HK,Biro PA,Cohen SN,Erlich HA,von Gabain A,Lawrance SK,Lemaux PG,McDevitt HO,Peterlin BM,Schulz MF,Sood AK,Weissman SM

更新日期：1983-03-01 00:00:00

abstract：:Habitat loss and disease are main drivers of global amphibian declines, yet the interaction between them remains largely unexplored. Here we show that paradoxically, habitat loss is negatively associated with occurrence, prevalence, and infection intensity of the chytrid fungus Batrachochytrium dendrobatidis (Bd) in a...

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

authors： Becker CG,Zamudio KR

更新日期：2011-06-14 00:00:00

abstract：:Cyclooxygenase (COX)-2, a rate-limiting enzyme of prostaglandin (PG) production, is overexpressed in colorectal adenomas and adenocarcinomas, and its inhibition by nonsteroidal antiinflammatory drugs protects against colorectal cancer. Mechanisms of cancer promotion by COX-2 are not fully understood, but signaling thr...

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

authors： Nishihara H,Kizaka-Kondoh S,Insel PA,Eckmann L

更新日期：2003-07-22 00:00:00

abstract：:The DNA strand exchange protein RAD51 facilitates the central step in homologous recombination, a process fundamentally important for accurate repair of damaged chromosomes, restart of collapsed replication forks, and telomere maintenance. The active form of RAD51 is a nucleoprotein filament that assembles on single-s...

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

authors： Subramanyam S,Ismail M,Bhattacharya I,Spies M

更新日期：2016-10-11 00:00:00

abstract：:The determination of macromolecular structures requires weighting of experimental evidence relative to prior physical information. Although it can critically affect the quality of the calculated structures, experimental data are routinely weighted on an empirical basis. At present, cross-validation is the most rigorou...

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

authors： Habeck M,Rieping W,Nilges M

更新日期：2006-02-07 00:00:00

abstract：:A MODEL OF THE LINEAR HYDROGEN BOND HAS BEEN DEVISED WHICH IS CHARACTERIZED BY THREE PHYSICAL PARAMETERS OF THE ISOLATED ELECTRON DONOR AND PROTON DONOR MOLECULES: mu(A-H), the bond dipole moment; DeltaI, the difference in ionization potential between that of the electron donor and the corresponding noble gas atom; an...

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

authors： Allen LC

更新日期：1975-12-01 00:00:00

abstract：:The aim of the present study was to assess possible adverse effects of transgene expression in leaves of field-grown barley relative to the influence of genetic background and the effect of plant interaction with arbuscular mycorrhizal fungi. We conducted transcript profiling, metabolome profiling, and metabolic finge...

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

authors： Kogel KH,Voll LM,Schäfer P,Jansen C,Wu Y,Langen G,Imani J,Hofmann J,Schmiedl A,Sonnewald S,von Wettstein D,Cook RJ,Sonnewald U

更新日期：2010-04-06 00:00:00

abstract：:A low molecular weight inhibitor of cell-free protein synthesis effective at subnanomolar concentrations is formed on incubation of cytoplasmic extracts from interferon-treated cells with double-stranded RNA and ATP. It can be conveniently synthesized by incubating a poly(I).poly(C)-Sepharose-bound enzyme fraction fro...

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

authors： Kerr IM,Brown RE

更新日期：1978-01-01 00:00:00

abstract：:The RNA world hypothesis presumes that RNA will be competent for varied essential cellular functions. One such indispensable cell function is regulation of membrane permeability. Though this was not a known RNA activity, selection-amplification yielded RNAs that bound phosphatidylcholine:cholesterol liposomes. At leas...

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

authors： Khvorova A,Kwak YG,Tamkun M,Majerfeld I,Yarus M

更新日期：1999-09-14 00:00:00

abstract：:Cell-based or pharmacological approaches for promoting tendon repair are currently not available because the molecular mechanisms of tendon development and healing are not well understood. Although analysis of knockout mice provides many critical insights, small animals such as mice have some limitations. In particula...

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

authors： Suzuki H,Ito Y,Shinohara M,Yamashita S,Ichinose S,Kishida A,Oyaizu T,Kayama T,Nakamichi R,Koda N,Yagishita K,Lotz MK,Okawa A,Asahara H

更新日期：2016-07-12 00:00:00

abstract：:Muscular dystrophy is a general term encompassing muscle disorders that cause weakness and wasting, typically leading to premature death. Membrane instability, as a result of a genetic disruption within the dystrophin-glycoprotein complex (DGC), is thought to induce myofiber degeneration, although the downstream mecha...

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

authors： Millay DP,Goonasekera SA,Sargent MA,Maillet M,Aronow BJ,Molkentin JD

更新日期：2009-11-10 00:00:00

abstract：:The complexity and specificity of metazoan transcription are determined by combinatorial control of the composition and activity of regulatory complexes. To investigate the basis of this specificity, we focused on the glucocorticoid receptor (GR), a single regulatory factor that integrates multiple signals to give ris...

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

authors： Chen SH,Masuno K,Cooper SB,Yamamoto KR

更新日期：2013-01-29 00:00:00

abstract：:Muscle wasting is a debilitating consequence of fasting, inactivity, cancer, and other systemic diseases that results primarily from accelerated protein degradation by the ubiquitin-proteasome pathway. To identify key factors in this process, we have used cDNA microarrays to compare normal and atrophying muscles and f...

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

authors： Gomes MD,Lecker SH,Jagoe RT,Navon A,Goldberg AL

更新日期：2001-12-04 00:00:00

abstract：:We studied the effects of carbon starvation and of varying the growth rate on the activity of each of the two tandem ribosomal RNA promoters from the rrnA operon of Escherichia coli. The cellular abundance of plasmid-encoded transcripts arising at promoters P1 and P2 and terminating at the ribosomal RNA terminator in ...

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

authors： Sarmientos P,Cashel M

更新日期：1983-11-01 00:00:00

abstract：:When the Mn(2+) and Ca(2+) ions normally present in concanavalin A are removed, the protein becomes incapable of binding saccharides. To explore the structural differences between the native and demetallized forms and their effects on the saccharide-binding properties of the protein, we have refined and compared the c...

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

authors： Reeke GN Jr,Becker JW,Edelman GM

更新日期：1978-05-01 00:00:00

abstract：:Control over structural transformations in supramolecular entities by external stimuli is critical for the development of adaptable and functional soft materials. Herein, we have designed and synthesized a dipyridyl donor containing a central Z-configured stiff-stilbene unit that self-assembles in the presence of two ...

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

authors： Yan X,Xu JF,Cook TR,Huang F,Yang QZ,Tung CH,Stang PJ

更新日期：2014-06-17 00:00:00

abstract：:Bacteriophage 434 encodes a repressor that, like bacteriophage lambda repressor, both activates and represses transcription. As in the lambda chromosome, a region of the 434 chromosome, called the right operator, contains three repressor binding sites (OR1, OR2, and OR3) that mediate these effects on two adjacent prom...

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

authors： Bushman FD,Ptashne M

更新日期：1986-12-01 00:00:00

abstract：:Cerebellar granule cells are the most abundant neurons in the brain, and granule cell precursors (GCPs) are a common target of transformation in the pediatric brain tumor medulloblastoma. Proliferation of GCPs is regulated by the secreted signaling molecule Sonic hedgehog (Shh), but the mechanisms by which Shh control...

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

authors： Oliver TG,Grasfeder LL,Carroll AL,Kaiser C,Gillingham CL,Lin SM,Wickramasinghe R,Scott MP,Wechsler-Reya RJ

更新日期：2003-06-10 00:00:00

abstract：:The dnaX gene (previously called dnaZX) of Escherichia coli has only one open reading frame for a 71-kDa polypeptide from which two distinct DNA polymerase III holoenzyme subunits, tau (71 kDa) and gamma (47 kDa), are produced. To determine how the gamma subunit is generated, we examined the influence of mutations in ...

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

authors： Tsuchihashi Z,Kornberg A

更新日期：1990-04-01 00:00:00

abstract：:Based on the cell surface expression of CD4 and CD8 molecules, murine thymocytes can be divided into four populations: these include CD4-, CD8- double-negative and CD4+, CD8+ double-positive subpopulations, both of which consist largely of immature cells, and the single positive, CD4+ or CD8+, subsets that contain fun...

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

authors： Nikolić-Zugić J,Bevan MJ

更新日期：1988-11-01 00:00:00

abstract：:The excision and reintegration of transposable elements (TEs) restructure their host genomes, generating cellular diversity involved in evolution, development, and the etiology of human diseases. Our current knowledge of TE behavior primarily results from bulk techniques that generate time and cell ensemble averages, ...

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

authors： Kim NH,Lee G,Sherer NA,Martini KM,Goldenfeld N,Kuhlman TE

更新日期：2016-06-28 00:00:00

abstract：:The Hawaiian Islands are renowned for some of the most spectacular species radiations in the world. Most of these radiations have been attributed to single colonization events, although the evidence supporting monophyletic origins is often poorly resolved and/or ambiguous. Without a concrete understanding of the origi...

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

authors： Gillespie RG,Croom HB,Palumbi SR

更新日期：1994-03-15 00:00:00

abstract：:We have reported previously that murine bone marrow-derived dendritic cells (DC) pulsed with whole tumor lysates can mediate potent antitumor immune responses both in vitro and in vivo. Because successful therapy was dependent on host immune T cells, we have now evaluated whether the systemic administration of the T c...

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

authors： Shimizu K,Fields RC,Giedlin M,Mulé JJ

更新日期：1999-03-02 00:00:00