Amorphous diamond-structured photonic crystal in the feather barbs of the scarlet macaw.

abstract：:In some countries across the globe, tropical forest cover is increasing. The national-scale reforestation of Vietnam since 1992 is assumed to contribute to this recovery. It is achieved, however, by the displacement of forest extraction to other countries on the order of 49 (34-70) M m(3), or approximately 39% of the ...

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

authors： Meyfroidt P,Lambin EF

更新日期：2009-09-22 00:00:00

abstract：:A fluorescence resonance energy transfer assay has been developed for monitoring Bacillus anthracis lethal factor (LF) protease activity. A fluorogenic 16-mer peptide based on the known LF protease substrate MEK1 was synthesized and found to be cleaved by the enzyme at the anticipated site. Extension of this work to a...

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

authors： Cummings RT,Salowe SP,Cunningham BR,Wiltsie J,Park YW,Sonatore LM,Wisniewski D,Douglas CM,Hermes JD,Scolnick EM

更新日期：2002-05-14 00:00:00

abstract：:The chloroplast stromal proteins from spinach condense the two heterocyclic moieties of vitamin B1--4-methyl-5-(beta-hydroxyethyl)thiazole and 2-methyl-4-amino-5-hydroxymethylpyrimidine--in the presence of MgATP. We have taken advantage of this observation to study thiazole synthesis. We present data indicating that p...

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

authors： Julliard JH,Douce R

更新日期：1991-03-15 00:00:00

abstract：:Despite an important role in vascular development and repair, the origin of endothelial progenitors remains unknown. Accumulating evidence indicates that cells derived from the hematopoietic system participate in angiogenesis. However, the identity and functional role of these cells remain controversial. Here we show ...

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

authors： Bailey AS,Willenbring H,Jiang S,Anderson DA,Schroeder DA,Wong MH,Grompe M,Fleming WH

更新日期：2006-08-29 00:00:00

abstract：:The photoaffinity herbicide azidoatrazine (2-azido-4-ethylamino-6-isopropylamino-s-triazine) selectively labels the L subunit of the reaction center of the photosynthetic bacterium Rhodopseudomonas sphaeroides. Herbicide-resistant mutants retain the L subunit and have altered binding properties for methylthio- and chl...

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

authors： Brown AE,Gilbert CW,Guy R,Arntzen CJ

更新日期：1984-10-01 00:00:00

abstract：:The wide diversity of dendritic trees is one of the most striking features of neural circuits. Here we develop a general quantitative theory relating the total length of dendritic wiring to the number of branch points and synapses. We show that optimal wiring predicts a 2/3 power law between these measures. We demonst...

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

authors： Cuntz H,Mathy A,Häusser M

更新日期：2012-07-03 00:00:00

abstract：:Cerebellar granule cells grown in the presence of a serum complex differentiate but are resistant to the lethal action of excitatory amino acids. When these cells are grown also in the presence of insulin-like growth factor I (IGF-I) they become fully susceptible to the toxic, lethal action of glutamate. The glutamate...

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

authors： Calissano P,Ciotti MT,Battistini L,Zona C,Angelini A,Merlo D,Mercanti D

更新日期：1993-09-15 00:00:00

abstract：:Herpes simplex virus type 1 (HSV-1) thymidine kinase is currently used as a suicide agent in the gene therapy of cancer. This therapy is based on the preferential phosphorylation of nucleoside analogs by tumor cells expressing HSV-1 thymidine kinase. However, the use of HSV-1 thymidine kinase is limited in part by the...

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

authors： Black ME,Newcomb TG,Wilson HM,Loeb LA

更新日期：1996-04-16 00:00:00

abstract：:Iron is an essential nutrient for the survival of most organisms and has played a central role in the virulence of many infectious disease pathogens. Mycobacterial IdeR is an iron-dependent repressor that shows 80% identity in the functional domains with its corynebacterial homologue, DtxR (diphtheria toxin repressor)...

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

authors： Manabe YC,Saviola BJ,Sun L,Murphy JR,Bishai WR

更新日期：1999-10-26 00:00:00

abstract：:Protein misfolding and aggregation cause serious degenerative conditions such as Alzheimer's, Parkinson, and prion diseases. Damage to membranes is thought to be one of the mechanisms underlying cellular toxicity of a range of amyloid assemblies. Previous studies have indicated that amyloid fibrils can cause membrane ...

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

authors： Milanesi L,Sheynis T,Xue WF,Orlova EV,Hellewell AL,Jelinek R,Hewitt EW,Radford SE,Saibil HR

更新日期：2012-12-11 00:00:00

abstract：:The plant kingdom contains vastly untapped natural product chemistry, which has been traditionally explored through the activity-guided approach. Here, we describe a gene-guided approach to discover and engineer a class of plant ribosomal peptides, the branched cyclic lyciumins. Initially isolated from the Chinese wol...

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

authors： Kersten RD,Weng JK

更新日期：2018-11-13 00:00:00

abstract：:A patient with type II diabetes associated with hyperproinsulinemia has been shown to have a point mutation in one insulin gene allele, resulting in replacement of histidine with aspartic acid at position 10 of the B-chain. To investigate the basis of the proinsulin processing defect, we introduced an identical mutati...

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

authors： Gross DJ,Halban PA,Kahn CR,Weir GC,Villa-Komaroff L

更新日期：1989-06-01 00:00:00

abstract：:A cDNA for parafusin, an evolutionarily conserved phosphoglycoprotein involved in exocytosis, has been cloned and sequenced from a unicellular eukaryote, Paramecium tetraurelia. A Paramecium cDNA library was screened with an oligonucleotide probe synthesized to an internal amino acid sequence of isolated parafusin. Th...

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

authors： Subramanian SV,Wyroba E,Andersen AP,Satir BH

更新日期：1994-10-11 00:00:00

abstract：:It was reported that the rate of elongation of partially reconstituted RNA, if prepared without centrifugation, showed dependency upon the state of protein aggregation like that found when free RNA was used as the nucleic acid source [Butler, P. J. G. (1974) J. Mol. Biol. 82, 333-341]. Butler concluded from this resul...

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

authors： Ohno T,Takahashi M,Okada Y

更新日期：1977-02-01 00:00:00

abstract：:Earlier we have shown that oscillations with a long period ("supercycles") may arise in two-locus systems experiencing cyclical selection with a short period. However, this mode of complex limiting behavior appeared to be possible for narrow ranges of parameters. Here we demonstrate that a multilocus system subjected ...

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

authors： Kirzhner VM,Korol AB,Nevo E

更新日期：1996-06-25 00:00:00

abstract：:We identified a viral IL-10 homolog encoded by an ORF (UL111a) within the human cytomegalovirus (CMV) genome, which we designated cmvIL-10. cmvIL-10 can bind to the human IL-10 receptor and can compete with human IL-10 for binding sites, despite the fact that these two proteins are only 27% identical. cmvIL-10 require...

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

authors： Kotenko SV,Saccani S,Izotova LS,Mirochnitchenko OV,Pestka S

更新日期：2000-02-15 00:00:00

abstract：:Bruton tyrosine kinase (EC 2.7.1.112) [Btk, encoded by Btk in mice and BTK in humans (formerly known as atk, BPK, or emb)], which is variously mutated in chromosome X-linked agammaglobulinemia patients and X-linked immunodeficient (xid) mice, has the pleckstrin homology (PH) domain at its amino terminus. The PH domain...

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

authors： Yao L,Kawakami Y,Kawakami T

更新日期：1994-09-13 00:00:00

abstract：:Plasma growth hormone (GH) profiles are sexually differentiated in many species and regulate the sex-dependence of peripubescent growth rates and liver function, including steroid hydroxylase cytochrome P450 expression, by mechanisms that are poorly understood. By use of an external pump to deliver to hypophysectomize...

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

authors： Waxman DJ,Pampori NA,Ram PA,Agrawal AK,Shapiro BH

更新日期：1991-08-01 00:00:00

abstract：:Secretion of extracellular polymeric substances (EPSs) by growing bacteria is an integral part of forming biofilm-like structures. In such dense systems, mechanical interactions among the structural components can be expected to significantly contribute to morphological properties. Here, we use a particle-based modeli...

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

authors： Ghosh P,Mondal J,Ben-Jacob E,Levine H

更新日期：2015-04-28 00:00:00

abstract：:The basic biochemical mechanisms underlying many heritable human polycystic diseases are unknown despite evidence that most cases are caused by mutations in members of several protein families, the most prominent being the polycystin gene family, whose products are found on the primary cilia, or due to mutations in po...

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

authors： Condac E,Silasi-Mansat R,Kosanke S,Schoeb T,Towner R,Lupu F,Cummings RD,Hinsdale ME

更新日期：2007-05-29 00:00:00

abstract：:Electron micrographs are shown of the first component of human complement (C1) which has been crosslinked with a water-soluble carbodiimide to prevent dissociation into its C1q and C1r2C1s2 subunits. Two projections of the crosslinked molecule are seen in the electron micrographs, which are called "top" and "profile."...

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

authors： Strang CJ,Siegel RC,Phillips ML,Poon PH,Schumaker VN

更新日期：1982-01-01 00:00:00

abstract：:Aged rats, displaying impairments in spatial learning and memory associated with marked cellular atrophy of forebrain cholinergic neurons, received intracerebroventricular infusions of one of the four neurotrophins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT-3), or neurotrop...

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

authors： Fischer W,Sirevaag A,Wiegand SJ,Lindsay RM,Björklund A

更新日期：1994-08-30 00:00:00

abstract：:In the vertebrate central nervous system, the retina has been a useful model for studies of cell fate determination. Recent results from studies conducted in vitro and in vivo suggest a model of retinal development in which both the progenitor cells and the environment change over time. The model is based upon the not...

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

authors： Cepko CL,Austin CP,Yang X,Alexiades M,Ezzeddine D

更新日期：1996-01-23 00:00:00

abstract：:The primary structure of proteins S1, the largest protein component of the Escherichia coli ribosome, has been elucidated by determining the amino acid sequence of the protein (from E. coli MRE600) and the nucleotide sequence of the S1 gene (rpsA, of a K-12 strain). The two methods gave results in perfect agreement ex...

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

authors： Schnier J,Kimura M,Foulaki K,Subramanian AR,Isono K,Wittmann-Liebold B

更新日期：1982-02-01 00:00:00

abstract：:Ca(2+) is essential for physiological depolarization-evoked synchronous neurotransmitter release. But, whether Ca(2+) influx or another factor controls release initiation is still under debate. The time course of ACh release is controlled by a presynaptic inhibitory G protein-coupled autoreceptor (GPCR), whose agonist...

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

authors： Kupchik YM,Rashkovan G,Ohana L,Keren-Raifman T,Dascal N,Parnas H,Parnas I

更新日期：2008-03-18 00:00:00

abstract：:Cells are dynamical systems of biomolecular interactions that process information from their environment to mount diverse yet specific responses. A key property of many self-organized systems is that of criticality: a state of a system in which, on average, perturbations are neither dampened nor amplified, but are pro...

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

authors： Nykter M,Price ND,Aldana M,Ramsey SA,Kauffman SA,Hood LE,Yli-Harja O,Shmulevich I

更新日期：2008-02-12 00:00:00

abstract：:This distance between a base next to the anticodon of tRNA and the 3' CpCpA terminus of the molecule has been estimated by singlet-singlet energy transfer experiments. The energy donor was the Y base of unknown structure found in yeast tRNA(phe). Three different energy acceptors were used: acriflavine, proflavinyl ace...

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

authors： Beardsley K,Cantor CR

更新日期：1970-01-01 00:00:00

abstract：:Cadherin/catenin-based adhesions coordinate cellular growth, survival, migration, and differentiation within a tissue by mechanically anchoring cells to their neighbors. They also intersect with diverse signaling pathways in development and cancer. Although the adhesive functions of adherens junction proteins are well...

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

authors： Livshits G,Kobielak A,Fuchs E

更新日期：2012-03-27 00:00:00

abstract：:Rett syndrome (RTT) is a severe neurodevelopmental disorder that affects about 1 in 10,000 female live births. The underlying cause of RTT is mutations in the X-linked gene, methyl-CpG-binding protein 2 (MECP2); however, the molecular mechanism by which these mutations mediate the RTT neuropathology remains enigmatic....

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

authors： Osenberg S,Karten A,Sun J,Li J,Charkowick S,Felice CA,Kritzer M,Nguyen MVC,Yu P,Ballas N

更新日期：2018-06-05 00:00:00

abstract：:Microstructural, δ(13)C isotope and C/N ratio investigations were conducted on excavated material from the black Younger Dryas boundary in Lommel, Belgium, aiming for a characterisation of the carbon content and structures. Cubic diamond nanoparticles are found in large numbers. The larger ones with diameters around o...

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

authors： Tian H,Schryvers D,Claeys P

更新日期：2011-01-04 00:00:00