On spin-exchange and electron-transfer rates in bacterial photosynthesis.

abstract：:The effects of calcium ion on the Na+ activation gate were studied in squid giant axons. Saxitoxin (STX) was used to block ion entry into Na+ channels without hindering access to the membrane surface, making it possible to distinguish surface effects of calcium from pore-occupancy effects. In the presence of STX, gati...

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

authors： Armstrong CM

更新日期：1999-03-30 00:00:00

abstract：:A vitamin D(3) metabolite in intestine more polar than 25-hydroxy-vitamin D(3)(25-OH D(3)) has been detected by countercurrent distribution. The intestinal metabolite is found also after administration of labeled hydroxy D(3), indicating that it arises from vitamin D(3) via the intermediate 25-hydroxy derivative. The ...

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

authors： Haussler MR,Boyce DW,Littledike ET,Rasmussen H

更新日期：1971-01-01 00:00:00

abstract：:Complex social behavior in Microtus voles and other mammals has been postulated to be under the direct genetic control of a single locus: the arginine vasopressin 1a receptor (avpr1a) gene. Using a phylogenetic approach, we show that a repetitive element in the promoter region of avpr1a, which reportedly causes social...

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

authors： Fink S,Excoffier L,Heckel G

更新日期：2006-07-18 00:00:00

abstract：:Cognitive flexibility depends on a fast neural learning mechanism for enhancing momentary relevant over irrelevant information. A possible neural mechanism realizing this enhancement uses fast spiking interneurons (FSIs) in the striatum to train striatal projection neurons to gate relevant and suppress distracting cor...

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

authors： Banaie Boroujeni K,Oemisch M,Hassani SA,Womelsdorf T

更新日期：2020-07-28 00:00:00

abstract：:A model is presented for age-specific selection on the genotypes in a population. Each genotype is assigned a life table that specifies the viability and fecundity of its age classes. Breeding and reproduction occur at regular intervals, and generations overlap. Examples were generated on a digital computer. Gene freq...

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

authors： Anderson WW,King CE

更新日期：1970-07-01 00:00:00

abstract：:Metalloproteases from at least two Gram-negative organisms selectively hydrolyze the surface of human fixed washed platelets. The protease-treated platelets lose their ability to aggregate with bovine von Willebrand factor and human von Willebrand factor plus ristocetin. The present study reports the membrane glycopro...

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

authors： Cooper HA,Bennett WP,White GC 2nd,Wagner RH

更新日期：1982-03-01 00:00:00

abstract：:In skeletal muscle, dihydropyridine receptors and dihydropyridine-sensitive Ca2+ channels are preferentially localized in the transverse tubular membranes. Starting with an antigenic membrane fraction enriched in rabbit muscle transverse tubules (T-tubules), several monoclonal antibodies were produced by a fusion of s...

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

authors： Malouf NN,Coronado R,McMahon D,Meissner G,Gillespie GY

更新日期：1987-07-01 00:00:00

abstract：:Alkylation of DNA by 7r,8t-dihydroxy,9t,10t-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (anti-BPDE) forms mainly trans adducts (with respect to the C-9/10 positions). We recently described a halide-catalyzed pathway that preferentially generates cis adducts and now report that the trans chlorohydrin of anti-BPDE (trans-BP...

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

authors： Meehan T,Wolfe AR,Negrete GR,Song Q

更新日期：1997-03-04 00:00:00

abstract：:It has been nearly 40 y since it was suggested that genomic methylation patterns could be transmitted via maintenance methylation during S phase and might play a role in the dynamic regulation of gene expression during development [Holliday R, Pugh JE (1975) Science 187(4173):226-232; Riggs AD (1975) Cytogenet Cell Ge...

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

authors： Bestor TH,Edwards JR,Boulard M

更新日期：2015-06-02 00:00:00

abstract：:A wide range of research has promised new tools for forecasting infectious disease dynamics, but little of that research is currently being applied in practice, because tools do not address key public health needs, do not produce probabilistic forecasts, have not been evaluated on external data, or do not provide suff...

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

authors： Johansson MA,Apfeldorf KM,Dobson S,Devita J,Buczak AL,Baugher B,Moniz LJ,Bagley T,Babin SM,Guven E,Yamana TK,Shaman J,Moschou T,Lothian N,Lane A,Osborne G,Jiang G,Brooks LC,Farrow DC,Hyun S,Tibshirani RJ,Rosenfe

更新日期：2019-11-26 00:00:00

abstract：:Zachariae Isstrøm (ZI) and Nioghalvfjerdsfjorden (79N) are marine-terminating glaciers in northeast Greenland that hold an ice volume equivalent to a 1.1-m global sea level rise. ZI lost its floating ice shelf, sped up, retreated at 650 m/y, and experienced a 5-gigaton/y mass loss. Glacier 79N has been more stable des...

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

authors： An L,Rignot E,Wood M,Willis JK,Mouginot J,Khan SA

更新日期：2021-01-12 00:00:00

abstract：:We explore the interactions of CYT-19, a DExD/H-box protein that functions in folding of group I RNAs, with a well characterized misfolded species of the Tetrahymena ribozyme. Consistent with its function, CYT-19 accelerates refolding of the misfolded RNA to its native state. Unexpectedly, CYT-19 performs another reac...

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

authors： Tijerina P,Bhaskaran H,Russell R

更新日期：2006-11-07 00:00:00

abstract：:Previous work has demonstrated a role for the E2F1 gene product in signaling apoptosis, both as a result of the deregulation of the Rb/E2F pathway as well as in response to DNA damage. We now show that the ability of cells to suppress the apoptotic potential of E2F1, as might occur during the course of normal cellular...

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

authors： Hallstrom TC,Nevins JR

更新日期：2003-09-16 00:00:00

abstract：:Translational initiation factor 2 (IF2) is a guanine nucleotide-binding protein that can bind guanosine 3',5'-(bis) diphosphate (ppGpp), an alarmone involved in stringent response in bacteria. In cells growing under optimal conditions, the GTP concentration is very high, and that of ppGpp very low. However, under stre...

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

authors： Milon P,Tischenko E,Tomsic J,Caserta E,Folkers G,La Teana A,Rodnina MV,Pon CL,Boelens R,Gualerzi CO

更新日期：2006-09-19 00:00:00

abstract：:We determined the complete nucleotide sequence of an infectious proviral molecular clone (FIV-14) of the feline immunodeficiency virus (FIV). FIV-14 has a genome organization similar in complexity to other lentiviruses. In addition to three large open reading frames representing the gag, pol, and env genes, at least f...

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

authors： Olmsted RA,Hirsch VM,Purcell RH,Johnson PR

更新日期：1989-10-01 00:00:00

abstract：:Nine subjects were studied by high-speed magnetic resonance imaging while performing language-based tasks. Subjects were asked either to repeat or to generate verbs associated with nouns read by an experimenter while magnetic resonance images were obtained of the left inferior frontal lobe. The echo-planar imaging seq...

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

authors： McCarthy G,Blamire AM,Rothman DL,Gruetter R,Shulman RG

更新日期：1993-06-01 00:00:00

abstract：:Shiverer (shi) is an autosomal recessive mutation in the mouse characterized by an almost total lack of central nervous system myelin. While small amounts of other myelin components are present in the brain of the shi mouse, the four forms of myelin basic protein (MBP) are not detectable. Previous investigations by us...

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

authors： Molineaux SM,Engh H,de Ferra F,Hudson L,Lazzarini RA

更新日期：1986-10-01 00:00:00

abstract：:Xenogeneic monoclonal antibodies were prepared to the murine interleukin 2 (IL-2)-dependent HT2 cell line. One rat IgM monoclonal antibody (7D4) was identified that inhibited proliferation of the HT2 cells and of IL-2-dependent CTLL cells in the presence of crude rat IL-2 as well as of purified human IL-2. The level o...

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

authors： Malek TR,Robb RJ,Shevach EM

更新日期：1983-09-01 00:00:00

abstract：:Regulatory T (Treg) cells expressing the transcription factor Foxp3 play an important role in maintaining immune homeostasis. Chronic inflammation is associated with reduced Foxp3 expression, function, and loss of phenotypic stability. Previous studies have established the importance of TNF receptor 2 (TNFR2) in the g...

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

authors： Tseng WY,Huang YS,Clanchy F,McNamee K,Perocheau D,Ogbechi J,Luo SF,Feldmann M,McCann FE,Williams RO

更新日期：2019-10-22 00:00:00

abstract：:Dihydroisohistrionicotoxin inhibits acetylcholine receptor-dependent 22Na+ uptake of cultured chick muscle cells with a KI of 0.2 micrometer. The inhibition is noncompetitive with respect to agonists. The toxin enhances desensitization of the receptor by agonists which is accompanied by a 10-fold increase in receptor ...

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

authors： Burgermeister W,Catterall WA,Witkop B

更新日期：1977-12-01 00:00:00

abstract：:Using T- and B-cell deficient C.B-17 mice with the scid mutation, we have previously documented the existence of a T-cell-independent but interferon gamma-dependent pathway of macrophage activation that confers upon the host partial resistance to the facultative intracellular bacterium Listeria monocytogenes. This pat...

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

authors： Rogers HW,Sheehan KC,Brunt LM,Dower SK,Unanue ER,Schreiber RD

更新日期：1992-02-01 00:00:00

abstract：:Many and diverse modifications of the myosin subfragment 1 (S-1) increase (modulate) its ATPase activity, including interaction of this particle with actin; a recent addition to these modifications is the extensive lysine modification of S-1 that seems prerequisite to crystallizing it for structure analysis. In this s...

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

authors： Bivin DB,Ue K,Khoroshev M,Morales M

更新日期：1994-08-30 00:00:00

abstract：:Surfaces with patterned wettability contrast are important in industrial applications such as heat transfer, water collection, and particle separation. Traditional methods of fabricating such surfaces rely on microfabrication technologies, which are only applicable to certain substrates and are difficult to scale up a...

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

authors： Chen D,McKinley GH,Cohen RE

更新日期：2016-07-19 00:00:00

abstract：:Reactive oxygen species (ROS) mediate abscisic acid (ABA) signaling in guard cells. To dissect guard cell ABA-ROS signaling genetically, a cell type-specific functional genomics approach was used to identify 2 MAPK genes, MPK9 and MPK12, which are preferentially and highly expressed in guard cells. To provide genetic ...

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

authors： Jammes F,Song C,Shin D,Munemasa S,Takeda K,Gu D,Cho D,Lee S,Giordo R,Sritubtim S,Leonhardt N,Ellis BE,Murata Y,Kwak JM

更新日期：2009-12-01 00:00:00

abstract：:Reinstatement of neural activity is hypothesized to underlie our ability to mentally travel back in time to recover the context of a previous experience. We used intracranial recordings to directly examine the precise spatiotemporal extent of neural reinstatement as 32 participants with electrodes placed for seizure m...

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

authors： Yaffe RB,Kerr MS,Damera S,Sarma SV,Inati SK,Zaghloul KA

更新日期：2014-12-30 00:00:00

abstract：:Cytological preparations of interphase nuclei and chromosomes from mouse 3T6 cells prepared at various times after infection with the murine sarcomaleukemia virus complex were hybridized with the [(3)H]DNA product of the viral RNA-directed DNA polymerase. While uninfected nuclei had an average of 4 autoradiographic gr...

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

authors： Loni MC,Green M

更新日期：1974-09-01 00:00:00

abstract：:The localization of endothelin 1 mRNA and endothelin-like immunoreactivity was investigated in samples of neurologically normal nervous system tissue from 10 adults by using in situ hybridization and immunocytochemistry. Tissue sections of spinal cord and dorsal root ganglia were hybridized with an 35S-radiolabeled en...

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

authors： Giaid A,Gibson SJ,Ibrahim BN,Legon S,Bloom SR,Yanagisawa M,Masaki T,Varndell IM,Polak JM

更新日期：1989-10-01 00:00:00

abstract：:A modified differential screening procedure was applied to analyze cDNA libraries of cloned helper T lymphocytes (Th) and cytolytic T lymphocytes (CTL). Negative and positive differential screening and RNA blot analysis were used to identify cDNA clones that were expressed preferentially in Th or CTL. Seven clones cor...

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

authors： Kwon BS,Kim GS,Prystowsky MB,Lancki DW,Sabath DE,Pan JL,Weissman SM

更新日期：1987-05-01 00:00:00

abstract：:Numerous investigations have focused on DNA damage induced by ionizing radiation; however, photoionization threshold energies of nucleic acid components in aqueous solution are not known. Herein, data from gas-phase photoelectron experiments have been combined with results from self-consistent field and post-self-cons...

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

authors： Fernando H,Papadantonakis GA,Kim NS,LeBreton PR

更新日期：1998-05-12 00:00:00

abstract：:The sigma-N (sigmaN) subunit of the bacterial RNA polymerase is a sequence specific DNA-binding protein. The RNA polymerase holoenzyme formed with sigmaN binds to promoters in an inactive form and only initiates transcription when activated by enhancer-binding positive control proteins. We now provide evidence to show...

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

authors： Cannon WV,Chaney MK,Wang X,Buck M

更新日期：1997-05-13 00:00:00