Starch grain and phytolith evidence for early ninth millennium B.P. maize from the Central Balsas River Valley, Mexico.

abstract：:Resonance Raman and optical absorption spectra of ligand-free (deoxy) myoglobin and CO-bound myoglobin (MbCO) at pH 2.6 have been measured by using continuous-flow/rapid-mixing techniques. The spectra of deoxy myoglobin at low pH within 6 ms of the pH drop demonstrate that the iron-histidine bond has been ruptured but...

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

authors： Han S,Rousseau DL,Giacometti G,Brunori M

更新日期：1990-01-01 00:00:00

abstract：:Visual information is conveyed from the eye to the brain by distinct types of retinal ganglion cells (RGCs). It is largely unknown how RGCs acquire their defining morphological and physiological features and connect to upstream and downstream synaptic partners. The three Brn3/Pou4f transcription factors (TFs) particip...

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

authors： Sajgo S,Ghinia MG,Brooks M,Kretschmer F,Chuang K,Hiriyanna S,Wu Z,Popescu O,Badea TC

更新日期：2017-05-16 00:00:00

abstract：:We develop a theoretical description of sperm chemotaxis. Sperm cells of many species are guided to the egg by chemoattractants, a process called chemotaxis. Motor proteins in the flagellum of the sperm generate a regular beat of the flagellum, which propels the sperm in a fluid. In the absence of a chemoattractant, s...

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

authors： Friedrich BM,Jülicher F

更新日期：2007-08-14 00:00:00

abstract：:Identifying targets is critical for understanding the biological effects of microRNA (miRNA) expression. The challenge lies in characterizing the cohort of targets for a specific miRNA, especially when targets are being actively down-regulated in miRNA- RNA-induced silencing complex (RISC)-messengerRNA (mRNA) complexe...

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

authors： Cambronne XA,Shen R,Auer PL,Goodman RH

更新日期：2012-12-11 00:00:00

abstract：:Mitochondria isolated from maize plants with S-type male-sterile cytoplasms are capable of synthesizing four species of RNA at concentrations of actinomycin D that eliminate all DNA-directed RNA synthesis. No RNA synthesis occurs under the same conditions with mitochondria from plants possessing normal (N) cytoplasm o...

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

authors： Finnegan PM,Brown GG

更新日期：1986-07-01 00:00:00

abstract：:For almost a century the plant hormone auxin has been central to theories on apical dominance, whereby the growing shoot tip suppresses the growth of the axillary buds below. According to the classic model, the auxin indole-3-acetic acid is produced in the shoot tip and transported down the stem, where it inhibits bud...

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

authors： Mason MG,Ross JJ,Babst BA,Wienclaw BN,Beveridge CA

更新日期：2014-04-22 00:00:00

abstract：:The enzyme tryptophan 2,3-dioxygenase [EC 1.13.11.11; L-tryptophan:oxygen 2,3-oxidoreductase (decyclizing)] first appears in the livers of young rats around the 15th postnatal day, and increases to the adult level by the 22nd day. Studies have shown that the appearance and subsequent development of the enzyme activity...

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

authors： Killewich LA,Feigelson P

更新日期：1977-12-01 00:00:00

abstract：:All cells are unavoidably exposed to chemicals that can alkylate DNA to form genotoxic damage. Among the various DNA lesions formed, O(6)-alkylguanine lesions can be highly cytotoxic, and we recently demonstrated that O(6)-methylguanine (O(6)MeG) and O(6)-chloroethylguanine (O(6)CEG) specifically initiate apoptosis in...

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

authors： Hickman MJ,Samson LD

更新日期：1999-09-14 00:00:00

abstract：:For more than a century we have understood that our brain's left hemisphere is the primary site for processing language, yet why this is so has remained more elusive. Using positron emission tomography, we report cerebral blood flow activity in profoundly deaf signers processing specific aspects of sign language in ke...

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

authors： Petitto LA,Zatorre RJ,Gauna K,Nikelski EJ,Dostie D,Evans AC

更新日期：2000-12-05 00:00:00

abstract：:Among the pathogenic processes contributing to dopaminergic neuron (DN) death in Parkinson disease (PD), evidence points to non-cell-autonomous mechanisms, particularly chronic inflammation mounted by activated microglia. Yet little is known about endogenous regulatory processes that determine microglial actions in pa...

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

authors： Ros-Bernal F,Hunot S,Herrero MT,Parnadeau S,Corvol JC,Lu L,Alvarez-Fischer D,Carrillo-de Sauvage MA,Saurini F,Coussieu C,Kinugawa K,Prigent A,Höglinger G,Hamon M,Tronche F,Hirsch EC,Vyas S

更新日期：2011-04-19 00:00:00

abstract：:Eukaryotic transcriptional activators may function by stimulating formation of RNA polymerase II preinitiation complexes at the core promoter of genes. In this case, their mode of action will intrinsically depend on how these complexes assemble on promoters in living cells, an issue that remains largely unexplored. He...

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

authors： Gonzalez-Couto E,Klages N,Strubin M

更新日期：1997-07-22 00:00:00

abstract：:This paper examines the relationship between various treatment parameters within a latent variable model when the effects of treatment depend on the recipient's observed and unobserved characteristics. We show how this relationship can be used to identify the treatment parameters when they are identified and to bound ...

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

authors： Heckman JJ,Vytlacil EJ

更新日期：1999-04-13 00:00:00

abstract：:p19ARF has been implicated as a key regulator of p53 stability and activation. While numerous stresses activate the p53 growth arrest pathway, those requiring p19ARF remain to be elucidated. We used p19ARF knockout mouse embryo fibroblasts to show that DNA damage and microtubule disruption require p19ARF to induce p53...

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

authors： Khan SH,Moritsugu J,Wahl GM

更新日期：2000-03-28 00:00:00

abstract：:Methyl groups placed on varphiXsB1 replicative form DNA by the Escherichia coli B modification enzyme are located in the overlap between fragments Mbo II-3 and Alu I-2, a 61-base-pair DNA segment. Mutations that led to loss of susceptibility to restriction by E. coli B occurred within this segment at three positions s...

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

authors： Lautenberger JA,Kan NC,Lackey D,Linn S,Edgell MH,Hutchison CA 3rd

更新日期：1978-05-01 00:00:00

abstract：:The fah1 mutant of Arabidopsis is defective in the accumulation of sinapic acid-derived metabolites, including the guaiacyl-syringyl lignin typical of angiosperms. Earlier results indicated that the FAH1 locus encodes ferulate-5-hydroxylase (F5H), a cytochrome P450-dependent monooxygenase (P450) of the general phenylp...

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

authors： Meyer K,Cusumano JC,Somerville C,Chapple CC

更新日期：1996-07-09 00:00:00

abstract：:Efforts are underway to construct several recoded genomes anticipated to exhibit multivirus resistance, enhanced nonstandard amino acid (nsAA) incorporation, and capability for synthetic biocontainment. Although our laboratory pioneered the first genomically recoded organism (Escherichia coli strain C321.∆A), its fitn...

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

authors： Wannier TM,Kunjapur AM,Rice DP,McDonald MJ,Desai MM,Church GM

更新日期：2018-03-20 00:00:00

abstract：:Stearic acid is toxic for T lymphocytes in vitro but has little effect on B lymphocytes. To investigate the molecular basis for this difference, purified murine T and B lymphocytes were compared for their abilities to incorporate and metabolize stearic acid. Unstimulated T and B cells incorporated identical amounts of...

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

authors： Buttke TM,Van Cleave S,Steelman L,McCubrey JA

更新日期：1989-08-01 00:00:00

abstract：:We measured quantitatively the binding affinities of purified Cro repressor to the chemically synthesized wild-type and mutant OR1 operators, consisting of all three possible base-pair substitutions and of thymine to uracil substitutions at each base-pair position of the 17-base-pair operator sequence. The sequence-sp...

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

authors： Takeda Y,Sarai A,Rivera VM

更新日期：1989-01-01 00:00:00

abstract：:The use of profiling by ethnicity or nationality to trigger secondary security screening is a controversial social and political issue. Overlooked is the question of whether such actuarial methods are in fact mathematically justified, even under the most idealized assumptions of completely accurate prior probabilities...

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

authors： Press WH

更新日期：2009-02-10 00:00:00

abstract：:The structures of the rearranged c-myc gene products derived from a rcp T(12;15) have been investigated in the MPC-11 (IgG2b kappa) plasmacytoma. The rcp T(12;15) in MPC-11 is a reciprocal exchange between the c-myc gene on chromosome 15 and the immunoglobulin gamma 2a switch region (S gamma 2a) on chromosome 12. The ...

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

authors： Stanton LW,Yang JQ,Eckhardt LA,Harris LJ,Birshtein BK,Marcu KB

更新日期：1984-02-01 00:00:00

abstract：:The perinuclear localization of myosin-V was investigated in a variety of cultured mammalian cells and in primary cultures of rat hippocampus. In all cells investigated, myosin-V immunoreactivity was associated with the centrosome. In interphase cells, myosin-V was found in pericentriolar material, and in both mother ...

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

authors： Espreafico EM,Coling DE,Tsakraklides V,Krogh K,Wolenski JS,Kalinec G,Kachar B

更新日期：1998-07-21 00:00:00

abstract：:The Snf1 protein kinase family has been conserved in eukaryotes. In the yeast Saccharomyces cerevisiae, Snf1 is essential for transcription of glucose-repressed genes in response to glucose starvation. The direct interaction between Snf1 and its activating subunit, Snf4, within the kinase complex is regulated by the g...

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

authors： Ludin K,Jiang R,Carlson M

更新日期：1998-05-26 00:00:00

abstract：:A half-century's worth of research has established the existence of numerous event-related potential components measuring different cognitive operations in humans including the selection of stimuli by covert attention mechanisms. Surprisingly, it is unknown whether nonhuman primates exhibit homologous electrophysiolog...

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

authors： Woodman GF,Kang MS,Rossi AF,Schall JD

更新日期：2007-09-18 00:00:00

abstract：:Motilin, [Met]enkephalin, [Leu]enkephalin, somatostatin, taurine, gamma-aminobutyric acid (GABA), and glycine were tested for their effects on Deiters neurons of the lateral vestibular nucleus in rabbits. Iontophoresis was carried out with multibarrelled micropipettes. All four peptides and three amino acids produced ...

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

authors： Chan-Palay V,Ito M,Tongroach P,Sakurai M,Palay S

更新日期：1982-05-01 00:00:00

abstract：:Many methods have been developed to search for homologous members of a protein family in databases, and the reliability of results and conclusions may be compromised if only one method is used, neglecting the others. Here we introduce a general scheme for combining such methods. Based on this scheme, we implemented a ...

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

authors： Alam I,Dress A,Rehmsmeier M,Fuellen G

更新日期：2004-09-21 00:00:00

abstract：:Embryonic stem cell-based therapies exhibit great potential for the treatment of Parkinson's disease (PD) because they can significantly rescue PD-like behaviors. However, whether the transplanted cells themselves release dopamine in vivo remains elusive. We and others have recently induced human embryonic stem cells ...

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

authors： Kang X,Xu H,Teng S,Zhang X,Deng Z,Zhou L,Zuo P,Liu B,Liu B,Wu Q,Wang L,Hu M,Dou H,Liu W,Zhu F,Li Q,Guo S,Gu J,Lei Q,Lü J,Mu Y,Jin M,Wang S,Jiang W,Liu K,Wang C,Li W,Zhang K,Zhou Z

更新日期：2014-11-04 00:00:00

abstract：:Notwithstanding important advances in the context of single-variant pathogenicity identification, novel breakthroughs in discerning the origins of many rare diseases require methods able to identify more complex genetic models. We present here the Variant Combinations Pathogenicity Predictor (VarCoPP), a machine-learn...

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

authors： Papadimitriou S,Gazzo A,Versbraegen N,Nachtegael C,Aerts J,Moreau Y,Van Dooren S,Nowé A,Smits G,Lenaerts T

更新日期：2019-06-11 00:00:00

abstract：:The colony-stimulating factors (CSFs) greatly influence mature macrophage function in vitro: macrophage (M)-CSF induces maturation of monocytes and enhances differentiated cell function; granulocyte-macrophage (GM)-CSF stimulates a variety of antimicrobial functions. In vivo M-CSF is thought to promote differentiation...

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

authors： De Nichilo MO,Burns GF

更新日期：1993-03-15 00:00:00

abstract：:The chemosmotic model provides a framework for visualizing energy-coupled reactions (vectorial reaction sequences, membrane-dependent gradient formation, and charge separation of reacting species) and a mechanism for energy coupling (indirect coupling between the driving and driven reaction sequences mediated by a mem...

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

authors： Green DE

更新日期：1981-04-01 00:00:00

abstract：:BDF1 [(C57BL/6 X DBA/2)F1] mice were primed with alum-absorbed ovalbumin, and their spleen cells were cultured with ovalbumin to activate antigen-primed T cells. The activated T cells were then propagated in interleukin 2-containing medium in the presence or absence of affinity-purified glycosylation-inhibiting factor...

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

authors： Iwata M,Ishizaka K

更新日期：1987-04-01 00:00:00