Palette of fluorinated voltage-sensitive hemicyanine dyes.

abstract：:Although the first observations of the inhibitory effect of methylation on gene activity were made almost a decade ago, the mechanism by which methyl groups affect transcription is still obscure. Here we use engineered promoters methylated in vitro in transient transfections to study the mechanism by which methylation...

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

authors： Levine A,Cantoni GL,Razin A

更新日期：1992-11-01 00:00:00

abstract：:Engraftment and maintenance of hematopoietic stem and progenitor cells (HSPC) depend on their ability to respond to extracellular signals from the bone marrow microenvironment, but the critical intracellular pathways integrating these signals remain poorly understood. Furthermore, recent studies provide contradictory ...

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

authors： Sanchez-Aguilera A,Lee YJ,Lo Celso C,Ferraro F,Brumme K,Mondal S,Kim C,Dorrance A,Luo HR,Scadden DT,Williams DA

更新日期：2011-06-07 00:00:00

abstract：:Theoretical and experimental optical, redox, and paramagnetic results are presented for models of siroheme, the iron isobacteriochlorin prosthetic group of nitrite and sulfite reductases, and of sirohydrochlorin, the metal-free siroheme that is an intermediate in the biosynthetic pathway to vitamin B(12). The facile o...

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

authors： Chang CK,Hanson LK,Richardson PF,Young R,Fajer J

更新日期：1981-05-01 00:00:00

abstract：:Early members of the dinosaur-pterosaur clade Ornithodira are very rare in the fossil record, obscuring our understanding of the origins of this important group. Here, we describe an early ornithodiran (Kongonaphon kely gen. et sp. nov.) from the Mid-to-Upper Triassic of Madagascar that represents one of the smallest ...

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

authors： Kammerer CF,Nesbitt SJ,Flynn JJ,Ranivoharimanana L,Wyss AR

更新日期：2020-07-28 00:00:00

abstract：:Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth-ocean-atmosphere dynamic exchange of elements. The ratios' dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previ...

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

authors： Lebrato M,Garbe-Schönberg D,Müller MN,Blanco-Ameijeiras S,Feely RA,Lorenzoni L,Molinero JC,Bremer K,Jones DOB,Iglesias-Rodriguez D,Greeley D,Lamare MD,Paulmier A,Graco M,Cartes J,Barcelos E Ramos J,de Lara A,Sanchez-Lea

更新日期：2020-09-08 00:00:00

abstract：:Cryptochromes are blue-light receptors mediating various light responses in plants and animals. The photochemical mechanism of cryptochromes is not well understood. It has been proposed that photoactivation of cryptochromes involves the blue-light-dependent photoreduction of flavin adenine dinucleotide via the electro...

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

authors： Li X,Wang Q,Yu X,Liu H,Yang H,Zhao C,Liu X,Tan C,Klejnot J,Zhong D,Lin C

更新日期：2011-12-20 00:00:00

abstract：:Recombination junctions of several Neurospora mitochondrial DNA (mtDNA) mutants and their revertants were identified. Their nucleotide sequences and putative secondary structures were determined in order to understand the nature of the elements involved in intramolecular recombination. Multiple deletions, involving th...

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

authors： Almasan A,Mishra NC

更新日期：1991-09-01 00:00:00

abstract：:Major changes in global rainfall patterns accompanied a northward shift of Earth's thermal equator at the onset of an abrupt climate change 14.6 kya. This northward pull of Earth's wind and rain belts stemmed from disintegration of North Atlantic winter sea ice cover, which steepened the interhemispheric meridional te...

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

authors： Broecker WS,Putnam AE

更新日期：2013-10-15 00:00:00

abstract：:Identification of genomic regions that control tissue-specific gene expression is currently problematic. ChIP and high-throughput sequencing (ChIP-seq) of enhancer-associated proteins such as p300 identifies some but not all enhancers active in a tissue. Here we show that co-occupancy of a chromatin region by multiple...

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

authors： He A,Kong SW,Ma Q,Pu WT

更新日期：2011-04-05 00:00:00

abstract：:Germ cells are required for the successful propagation of sexually reproducing species. Understanding the mechanisms by which these cells are specified and how their totipotency is established and maintained has important biomedical and evolutionary implications. Freshwater planarians serve as fascinating models for s...

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

authors： Wang Y,Zayas RM,Guo T,Newmark PA

更新日期：2007-04-03 00:00:00

abstract：:Deciding whether a set of objects are the same or different is a cornerstone of perception and cognition. Surprisingly, no principled quantitative model of sameness judgment exists. We tested whether human sameness judgment under sensory noise can be modeled as a form of probabilistically optimal inference. An optimal...

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

authors： van den Berg R,Vogel M,Josic K,Ma WJ

更新日期：2012-02-21 00:00:00

abstract：:Changes in cyclic nucleotide metabolism similar to those characteristic of the chronic forms of hypertension were observed in an acute neurogenic form of hypertension in rats produced by electrolytic lesions of the nucleus tractus solitarii. These changes that were evident 2 hr after the lesions were made included dec...

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

authors： Amer MS,Doba N,Reis DJ

更新日期：1975-06-01 00:00:00

abstract：:Inorganic polyphosphate (polyP) is composed of linear chains of phosphate groups linked by high-energy phosphoanhydride bonds. However, this simple, ubiquitous molecule remains poorly understood. The use of nonstandardized analytical methods has contributed to this lack of clarity. By using improved polyacrylamide gel...

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

authors： Livermore TM,Chubb JR,Saiardi A

更新日期：2016-01-26 00:00:00

abstract：:5 alpha-Cholest-8(14)-en-3 beta-ol-15-one has been found to have significant hypocholesterolemic activity upon oral administration at a daily dosage of 75 mg/kg of body weight to Rhesus monkeys fed a diet of moderate cholesterol (Chol) content [0.19 mg/kcal (1 cal = 4.184 J) of diet]. The reductions in total serum Cho...

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

authors： Schroepfer GJ Jr,Sherrill BC,Wang KS,Wilson WK,Kisic A,Clarkson TB

更新日期：1984-11-01 00:00:00

abstract：:Two-dimensional Raman-terahertz (THz) spectroscopy is presented as a multidimensional spectroscopy directly in the far-IR regime. The method is used to explore the dynamics of the collective intermolecular modes of liquid water at ambient temperatures that emerge from the hydrogen-bond networks water forming. Two-dime...

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

authors： Savolainen J,Ahmed S,Hamm P

更新日期：2013-12-17 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

abstract：:Diabetes is now the most common cause of progressive kidney failure leading to dialysis or transplantation. The central pathological feature of diabetic nephropathy is accumulation of extracellular matrix within the glomeruli. The factors in the diabetic milieu responsible for extracellular matrix accumulation are not...

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

authors： Yamamoto T,Nakamura T,Noble NA,Ruoslahti E,Border WA

更新日期：1993-03-01 00:00:00

abstract：:During exercise, increased energy demands are met by increased glucose production that occurs simultaneously with the increased glucose uptake. We had previously observed that, during exercise, metabolic clearance rate of glucose (MCR) increases markedly in normal, but only marginally in poorly controlled diabetic dog...

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

authors： Miles PD,Yamatani K,Lickley HL,Vranic M

更新日期：1991-02-15 00:00:00

abstract：:Myosin-binding protein C (MyBP-C) is a thick filament protein playing an essential role in muscle contraction, and MyBP-C mutations cause heart and skeletal muscle disease in millions worldwide. Despite its discovery 40 y ago, the mechanism of MyBP-C function remains unknown. In vitro studies suggest that MyBP-C could...

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

authors： Luther PK,Winkler H,Taylor K,Zoghbi ME,Craig R,Padrón R,Squire JM,Liu J

更新日期：2011-07-12 00:00:00

abstract：:The accuracy of computer predictions of RNA secondary structure from sequence data and free energy parameters has been increased to roughly 70%. Performance is judged by comparison with structures known from phylogenetic analysis. The algorithm also generates suboptimal structures. On average, the best structure withi...

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

authors： Jaeger JA,Turner DH,Zuker M

更新日期：1989-10-01 00:00:00

abstract：:A type of heritable cellular change, known as habituation, occurs spontaneously in plant tissue and cell culture. This phenomenon is characterized by a newly acquired capacity of plant cells to produce growth regulatory substances. Using cloned lines of tobacco pith parenchyma cells, we demonstrated that a newly acqui...

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

authors： Binns A,Meins F

更新日期：1973-09-01 00:00:00

abstract：:The larger structures are, the lower their mechanical strength. Already discussed by Leonardo da Vinci and Edmé Mariotte several centuries ago, size effects on strength remain of crucial importance in modern engineering for the elaboration of safety regulations in structural design or the extrapolation of laboratory r...

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

authors： Weiss J,Girard L,Gimbert F,Amitrano D,Vandembroucq D

更新日期：2014-04-29 00:00:00

abstract：:Pollen tubes are highly polarized plant cells specialized in delivering sperm for fertilization. Pollen tube growth is rapid, occurs exclusively at the tip, and can reach distances thousands of times the diameter of the pollen grain without cell division, thus representing an excellent model system for studying asymme...

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

authors： Cheung AY,Niroomand S,Zou Y,Wu HM

更新日期：2010-09-14 00:00:00

abstract：:The autoimmune dermatologic disease pemphigus vulgaris (PV) is associated with the HLA serotypes DR4 and DRw6. Susceptibility to PV could be conferred either by sequences shared between the DR4 and DRw6 haplotypes or by different sequences in these haplotypes. We have examined the distribution of DR and DQ beta-chain ...

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

authors： Scharf SJ,Friedmann A,Brautbar C,Szafer F,Steinman L,Horn G,Gyllensten U,Erlich HA

更新日期：1988-05-01 00:00:00

abstract：:The use of proteasome inhibitors to target cancer's dependence on altered protein homeostasis has been greatly limited by intrinsic and acquired resistance. Analyzing data from thousands of cancer lines and tumors, we find that those with suppressed expression of one or more 19S proteasome subunits show intrinsic prot...

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

authors： Tsvetkov P,Sokol E,Jin D,Brune Z,Thiru P,Ghandi M,Garraway LA,Gupta PB,Santagata S,Whitesell L,Lindquist S

更新日期：2017-01-10 00:00:00

abstract：:Patients undergoing treatment at a community-based renal dialysis clinic were monitored monthly for hepatitis B surface antigen (HBsAg) and antibody to HBsAg (anti-HBs). Of 160 patients who began treatment HBsAg(-)/anti-HBs(-), 77 subsequently became HBsAg(+). Once HBsAg(+), males were more likely to remain HBsAg(+) i...

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

authors： London WT,Drew JS

更新日期：1977-06-01 00:00:00

abstract：:Recent genome-wide nucleosome mappings along with bioinformatics studies have confirmed that the DNA sequence plays a more important role in the collective organization of nucleosomes in vivo than previously thought. Yet in living cells, this organization also results from the action of various external factors like D...

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

authors： Milani P,Chevereau G,Vaillant C,Audit B,Haftek-Terreau Z,Marilley M,Bouvet P,Argoul F,Arneodo A

更新日期：2009-12-29 00:00:00

abstract：:We have isolated from vaccinia virus cores an enzyme, 5'-phosphate-polyribonucleotide kinase, that in the presence of ATP and Mg2+ catalyzes the conversion of 5'-phosphate and 5'-diphosphate termini of RNA to the 5'-triphosphate species. With the exception of dATP, other nucleoside triphosphates were inactive as phosp...

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

authors： Spencer E,Loring D,Hurwitz J,Monroy G

更新日期：1978-10-01 00:00:00

abstract：:Understanding the molecular determinants of specificity in protein-protein interaction is an outstanding challenge of postgenome biology. The availability of large protein databases generated from sequences of hundreds of bacterial genomes enables various statistical approaches to this problem. In this context covaria...

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

authors： Weigt M,White RA,Szurmant H,Hoch JA,Hwa T

更新日期：2009-01-06 00:00:00

abstract：:Recently, we established that satellite III (TGGAA)n tandem repeats, which occur at the centromeres of human chromosomes, pair with themselves to form an unusual "self-complementary" antiparallel duplex containing (GGA)2 motifs in which two unpaired guanines from opposite strands intercalate between sheared G.A base p...

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

authors： Zhu L,Chou SH,Reid BR

更新日期：1996-10-29 00:00:00