Interisland and interarchipelago transfer of stone tools in prehistoric Polynesia.

abstract：:In spite of the diversity of possible biological forms observed in nature, a limited range of morphospace is frequently occupied for a given trait. Several mechanisms have been proposed to explain this bias in the distribution of phenotypes including selection, drift, and developmental constraints. Despite extensive w...

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

authors： Malagón JN,Ahuja A,Sivapatham G,Hung J,Lee J,Muñoz-Gómez SA,Atallah J,Singh RS,Larsen E

更新日期：2014-09-30 00:00:00

abstract：:Type IV pili (Tfp) are highly conserved macromolecular structures that fulfill diverse cellular functions, such as adhesion to host cells, the import of extracellular DNA, kin recognition, and cell motility (twitching). Outstandingly, twitching motility enables a poorly understood process by which highly coordinated g...

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

authors： Mercier R,Bautista S,Delannoy M,Gibert M,Guiseppi A,Herrou J,Mauriello EMF,Mignot T

更新日期：2020-11-10 00:00:00

abstract：:The computation of motion plays a central role in visual orientation. The fly has been successfully used as a model system for analyzing the mechanisms underlying motion detection. Thereby, much attention has been paid to a neuronal circuit of individually identifiable neurons in the third visual ganglion that extract...

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

authors： Borst A,Egelhaaf M

更新日期：1992-05-01 00:00:00

abstract：:Fast axoplasmic transport was studied in dorsal root ganglion cells of the cat. Proteins carried in the fast axoplasmic flow were labeled after an intraganglionic injection of (L)-[4,5-(3)H]leucine. The rate of transport was 380 +/- 26 mm/day in both the central and peripheral branches of the bifurcating axons that ar...

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

authors： Anderson LE,McClure WO

更新日期：1973-05-01 00:00:00

abstract：:Aconitase (Aco1p) is a multifunctional protein: It is an enzyme of the tricarboxylic acid cycle. In animal cells, Aco1p also is a cytosolic protein binding to mRNAs to regulate iron metabolism. In yeast, Aco1p was identified as a component of mtDNA nucleoids. Here we show that yeast Aco1p protects mtDNA from excessive...

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

authors： Chen XJ,Wang X,Butow RA

更新日期：2007-08-21 00:00:00

abstract：:Microtubules (MTs) are hollow cytoskeletal filaments assembled from αβ-tubulin heterodimers. Tau, an unstructured protein found in neuronal axons, binds to MTs and regulates their dynamics. Aberrant Tau behavior is associated with neurodegenerative dementias, including Alzheimer's. Here, we report on a direct force me...

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

authors： Chung PJ,Choi MC,Miller HP,Feinstein HE,Raviv U,Li Y,Wilson L,Feinstein SC,Safinya CR

更新日期：2015-11-24 00:00:00

abstract：:Understanding the different categories of facial expressions of emotion regularly used by us is essential to gain insights into human cognition and affect as well as for the design of computational models and perceptual interfaces. Past research on facial expressions of emotion has focused on the study of six basic ca...

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

authors： Du S,Tao Y,Martinez AM

更新日期：2014-04-15 00:00:00

abstract：:Establishing quantitative relationships between molecular structure and broad biological effects has been a longstanding challenge in science. Currently, no method exists for forecasting broad biological activity profiles of medicinal agents even within narrow boundaries of structurally similar molecules. Starting fro...

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

authors： Fliri AF,Loging WT,Thadeio PF,Volkmann RA

更新日期：2005-01-11 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：:Chromophore-assisted light inactivation is a promising technique to inactivate selected proteins with high spatial and temporal resolution in living cells, but its use has been limited because of the lack of a methodology to prevent nonspecific photodamage in the cell owing to reactive oxygen species generated by the ...

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

authors： Yogo T,Urano Y,Mizushima A,Sunahara H,Inoue T,Hirose K,Iino M,Kikuchi K,Nagano T

更新日期：2008-01-08 00:00:00

abstract：:The mechanism by which mammalian cells acquire resistance to chemotherapeutic agents has been investigated by using molecular genetic techniques. LZ and C5, two independently derived multidrug-resistant Chinese hamster cell lines, share specific amplified DNA sequences. We demonstrate that commonly amplified DNA seque...

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

authors： Gros P,Croop J,Roninson I,Varshavsky A,Housman DE

更新日期：1986-01-01 00:00:00

abstract：:It has been proposed that extensive wildfires occurred after the Cretaceous-Tertiary (K-T) impact event. An abundance of soot and pyrosynthetic polycyclic aromatic hydrocarbons (pPAHs) in marine K-T boundary impact rocks (BIRs) have been considered support for this hypothesis. However, nonmarine K-T BIRs, from across ...

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

authors： Belcher CM,Finch P,Collinson ME,Scott AC,Grassineau NV

更新日期：2009-03-17 00:00:00

abstract：:We investigate the hypothesis that two classes of Ca2+ currents, one quickly inactivated by Ca2+ and one slowly inactivated by voltage, contribute to bursting electrical activity in pancreatic islets. A mathematical model of these currents is fit to the experimental whole-cell current-voltage and inactivation profiles...

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

authors： Keizer J,Smolen P

更新日期：1991-05-01 00:00:00

abstract：:Recent studies have shown that the genes of the gibberellin (GA) biosynthesis pathway in the fungus Gibberella fujikuroi are organized in a cluster of at least seven genes. P450-1 is one of four cytochrome P450 monooxygenase genes in this cluster. Disruption of the P450-1 gene in the GA-producing wild-type strain IMI ...

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

authors： Rojas MC,Hedden P,Gaskin P,Tudzynski B

更新日期：2001-05-08 00:00:00

abstract：:Synapse formation at the neuromuscular junction (NMJ) requires an alternatively spliced variant of agrin (Z(+) agrin) that is produced only by neurons. Here, we show that Nova1 and Nova2, neuron-specific splicing factors identified as targets in autoimmune motor disease, are essential regulators of Z(+) agrin. Nova1/N...

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

authors： Ruggiu M,Herbst R,Kim N,Jevsek M,Fak JJ,Mann MA,Fischbach G,Burden SJ,Darnell RB

更新日期：2009-03-03 00:00:00

abstract：:2(S)-dihydroxypropanesulfonate (DHPS) is a microbial degradation product of 6-deoxy-6-sulfo-d-glucopyranose (sulfoquinovose), a component of plant sulfolipid with an estimated annual production of 1010 tons. DHPS is also at millimolar levels in highly abundant marine phytoplankton. Its degradation and sulfur recycling...

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

authors： Liu J,Wei Y,Lin L,Teng L,Yin J,Lu Q,Chen J,Zheng Y,Li Y,Xu R,Zhai W,Liu Y,Liu Y,Cao P,Ang EL,Zhao H,Yuchi Z,Zhang Y

更新日期：2020-07-07 00:00:00

abstract：:A polyclonal antiserum directed against the C-terminal domain of dystrophin was used to isolate a cDNA clone encoding an antigenically cross-reactive protein, microtubule-associated protein 1B (MAP-1B). Physical mapping of the human MAP-1B locus places its chromosomal location at 5q13, in proximity to the spinal muscu...

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

authors： Lien LL,Boyce FM,Kleyn P,Brzustowicz LM,Menninger J,Ward DC,Gilliam TC,Kunkel LM

更新日期：1991-09-01 00:00:00

abstract：:The nerve growth factor (NGF)-mediated increase in c-fos gene expression in the rat pheochromocytoma PC12 cell line has been investigated. NGF treatment of PC12 cells results in an increased level of c-fos mRNA within 15 min. An approximately 100-fold increase in the level of c-fos mRNA occurs 30-45 min after exposure...

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

authors： Milbrandt J

更新日期：1986-07-01 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：:d-alanine-d-lactate ligase from Enterococcus faecium BM4147 is directly responsible for the biosynthesis of alternate cell-wall precursors in bacteria, which are resistant to the glycopeptide antibiotic vancomycin. The crystal structure has been determined with data extending to 2.5-A resolution. This structure shows ...

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

authors： Roper DI,Huyton T,Vagin A,Dodson G

更新日期：2000-08-01 00:00:00

abstract：:Bordetella pertussis, the causative agent of whooping cough, secretes several toxins implicated in this disease. One of these putative virulence factors is the adenylate cyclase (AC) toxin that elevates intracellular cAMP in eukaryotic cells to cytotoxic levels. This toxin is a bifunctional protein comprising both AC ...

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

authors： Gross MK,Au DC,Smith AL,Storm DR

更新日期：1992-06-01 00:00:00

abstract：:The genes for platelet-derived growth factor (PDGF) A chain, B chain/c-sis, and the PDGF receptor are expressed in human malignant glioma cell lines. In the present investigation we have studied the expression of these genes in biopsy specimens from human glioblastomas. Hyperplasia of the vascular endothelium is a pro...

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

authors： Hermansson M,Nistér M,Betsholtz C,Heldin CH,Westermark B,Funa K

更新日期：1988-10-01 00:00:00

abstract：:A series of pyrimidine nucleoside analogues containing [2',5'-bis-O-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino- 1'',2''-oxathiole-2'',2''-dioxide)]-beta-D-ribofuranose as the pentose were found to inhibit human immunodeficiency virus type 1 [HIV-1(IIIB)] replication at a concentration of 0.06-0.8 microM but wer...

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

authors： Balzarini J,Pérez-Pérez MJ,San-Félix A,Schols D,Perno CF,Vandamme AM,Camarasa MJ,De Clercq E

更新日期：1992-05-15 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：:Like all aliphatic amines, the polyamines spermine and spermidine are physical quenchers of singlet molecular oxygen (1O2*). The rate constants of these processes were determined in vitro with photochemically generated 1O2* and the hydrocarbon rubrene as substrate, in pyridine. At millimolar concentration, spermine an...

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

authors： Khan AU,Mei YH,Wilson T

更新日期：1992-12-01 00:00:00

abstract：:We have constructed three different fusion genes containing the herpes simplex virus thymidine kinase (HSV tk) and the bacterial neomycin phosphotransferase (neo) genes. All three fusion genes utilize the HSV tk promoter but differ at the junction of their components. We have determined if the fusion genes are bifunct...

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

authors： Schwartz F,Maeda N,Smithies O,Hickey R,Edelmann W,Skoultchi A,Kucherlapati R

更新日期：1991-12-01 00:00:00

abstract：:Hybridization of human T cells with an azaguanine-resistant human T cell line gave rise to T hybrid cell lines secreting several immunoregulatory molecules. Analyses of karyotypes, HLA phenotypes, and other surface phenotypes, such as T-cell-specific antigens or receptors for sheep erythrocytes and the patterns of mit...

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

authors： Okada M,Yoshimura N,Kaieda T,Yamamura Y,Kishimoto T

更新日期：1981-12-01 00:00:00

abstract：:The proton markers located in the minor groove of the d(C-G-C-G-A-A-T-T-C-G-C-G) duplex and its netropsin complex have been assigned from measurements of intramolecular nuclear Overhauser effects (NOEs) between exchangeable imino protons and nonexchangeable base protons on the same and adjacent base pairs. Several poi...

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

authors： Patel DJ

更新日期：1982-11-01 00:00:00

abstract：:Myosin II is a molecular motor that converts chemical to mechanical energy and enables muscle operations. After a power stroke, a recovery transition completes the cycle and returns the molecular motor to its prestroke state. Atomically detailed simulations in the framework of the Milestoning theory are used to calcul...

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

authors： Elber R,West A

更新日期：2010-03-16 00:00:00

abstract：:Newborns are at increased risk of jaundice, a condition in which excess bilirubin accumulates in blood. Left untreated, jaundice can lead to neurological impairment and death. Jaundice resulting from unconjugated hyperbilirubinemia is easily treated with exposure to blue light, and phototherapy systems have been devel...

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

authors： Keahey PA,Simeral ML,Schroder KJ,Bond MM,Mtenthaonnga PJ,Miros RH,Dube Q,Richards-Kortum RR

更新日期：2017-12-19 00:00:00