A unique basaltic micrometeorite expands the inventory of solar system planetary crusts.

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：:A de novo mutation in the KCND2 gene, which encodes the Kv4.2 K+ channel, was identified in twin boys with intractable, infant-onset epilepsy and autism. Kv4.2 channels undergo closed-state inactivation (CSI), a mechanism by which channels inactivate without opening during subthreshold depolarizations. CSI dynamically...

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

authors： Lin MA,Cannon SC,Papazian DM

更新日期：2018-04-10 00:00:00

abstract：:Responses of tethered cells of Escherichia coli to impulse, step, exponential-ramp or exponentiated sine-wave stimuli are internally consistent, provided that allowance is made for the nonlinear effect of thresholds. This result confirms that wild-type cells exposed to stimuli in the physiological range make short-ter...

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

authors： Segall JE,Block SM,Berg HC

更新日期：1986-12-01 00:00:00

abstract：:Embryonic pluripotency in the mouse is established and maintained by a gene-regulatory network under the control of a core set of transcription factors that include octamer-binding protein 4 (Oct4; official name POU domain, class 5, transcription factor 1, Pou5f1), sex-determining region Y (SRY)-box containing gene 2 ...

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

authors： Fernandez-Tresguerres B,Cañon S,Rayon T,Pernaute B,Crespo M,Torroja C,Manzanares M

更新日期：2010-11-16 00:00:00

abstract：:T4 polynucleotide ligase efficiently catalyzes the head-to-tail joining of the ribo-oligoadenylates, r-(pA)(8) and r-(pA)(10), in the presence of high molecular weight deoxypolythymidylate. The enzyme also catalyzes the joining of deoxy-oligothymidylates, e.g., d-(pT)(10), in the presence of ribopolyadenylate. The enz...

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

authors： Kleppe K,Van de Sande JH,Khorana HG

更新日期：1970-09-01 00:00:00

abstract：:We prove theorems on the structure of the fundamental group of a compact riemannian manifold of non-positive curvature. In particular, a conjecture of J. Wolf [J. Differential Geometry, 2, 421-446 (1968)] is proved. ...

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

authors： Yau ST

更新日期：1970-10-01 00:00:00

abstract：:The role of the products of the K and D loci of the H-2 complex as target antigens for cytotoxic T cells generated to modified syngeneic cells has been investigated. Spleen cells, when cocultured with trinitrophenyl-derivatized syngeneic cells, generate cytolytic T cells that lyse most effectively tumor or spleen targ...

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

authors： Burakoff SJ,Germain RN,Dorf ME,Benacerrah B

更新日期：1976-02-01 00:00:00

abstract：:In order to assess whether DNA rearrangement occurs with equal frequency at each of the several J (joining region) elements in the mouse kappa light chain locus, we set out to determine the relative frequency of usage of J kappa segments in populations of B lymphocytes unperturbed by antigenic selection or cloning. To...

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

authors： Wood DL,Coleclough C

更新日期：1984-08-01 00:00:00

abstract：:Several models have been proposed for the infectious agents that cause human Creutzfeldt-Jakob disease (CJD) and sheep scrapie. Purified proteins and extracted nucleic acids are not infectious. To further identify the critical molecular components of the CJD agent, 120S infectious material with reduced prion protein (...

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

authors： Manuelidis L,Sklaviadis T,Akowitz A,Fritch W

更新日期：1995-05-23 00:00:00

abstract：:Delta 5-3-Ketosteroid isomerase (EC 5.3.3.1) promotes an allylic rearrangement involving intramolecular proton transfer via a dienolic intermediate. This enzyme enhances the catalytic rate by a factor of 10(10). Two residues, Tyr-14, the general acid that polarizes the steroid 3-carbonyl group and facilitates enolizat...

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

authors： Zhao Q,Abeygunawardana C,Talalay P,Mildvan AS

更新日期：1996-08-06 00:00:00

abstract：:We have previously shown that hepatitis B virus (HBV) replication is controlled by noncytolytic mechanisms that depend primarily on the effector functions of the CD8(+) T cell response, especially the production of IFN-gamma in the liver. The mechanisms that control the nuclear pool of viral covalently closed circular...

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

authors： Wieland SF,Spangenberg HC,Thimme R,Purcell RH,Chisari FV

更新日期：2004-02-17 00:00:00

abstract：:Production of reactive oxygen intermediates (ROI) and a form of programmed cell death called hypersensitive response (HR) are often associated with disease resistance of plants. We have previously shown that the Rac homolog of rice, OsRac1, is a regulator of ROI production and cell death in rice. Here we show that the...

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

authors： Ono E,Wong HL,Kawasaki T,Hasegawa M,Kodama O,Shimamoto K

更新日期：2001-01-16 00:00:00

abstract：:Fetal cells, potentially usable for prenatal diagnosis, were sorted from maternal blood samples taken as early as 15 weeks of gestation. Immunogenetic and cytogenic criteria established the fetal origin of the observed cells: Y-chromatin-containing (male) cells were detected in the sorted sample if and only if the new...

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

authors： Herzenberg LA,Bianchi DW,Schröder J,Cann HM,Iverson GM

更新日期：1979-03-01 00:00:00

abstract：:In t(15;17) acute promyelocytic leukemia, all-trans retinoic acid (RA) induces leukemic cell maturation in vitro and remission in acute promyelocytic leukemia patients, but in vivo treatments invariably lead to relapse with resistance to RA. NB4, a maturation-inducible cell line, and NB4-RAr sublines (R1 and R2) displ...

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

authors： Ruchaud S,Duprez E,Gendron MC,Houge G,Genieser HG,Jastorff B,Doskeland SO,Lanotte M

更新日期：1994-08-30 00:00:00

abstract：:Individual cell types are defined by architecturally and functionally specialized cortical domains. The Ezrin, Radixin, and Moesin (ERM) proteins play a major role in organizing cortical domains by assembling membrane protein complexes and linking them to the cortical actin cytoskeleton. Many studies have focused on t...

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

authors： Casaletto JB,Saotome I,Curto M,McClatchey AI

更新日期：2011-07-19 00:00:00

abstract：:Leukosialin (also known as Ly48, CD43, and sialophorin) is a major cell surface sialoglycoprotein found on a variety of hematopoietically derived cells. The precise function of this molecule is poorly understood but it has been implicated in cell proliferation and intercellular adhesion. We developed a transgenic mous...

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

authors： Dragone LL,Barth RK,Sitar KL,Disbrow GL,Frelinger JG

更新日期：1995-01-17 00:00:00

abstract：:Marked hypoalphalipoproteinemia was found together with relatively low serum cholesterol, triacylglycerol, and LDL levels in a triose-phosphate isomerase (TPI; D-glyceraldehyde-3-phosphate ketol-isomerase, EC 5.3.1.1)-deficient Hungarian family, especially in the two compound-heterozygote brothers. Apart from a slight...

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

authors： Hollán S,Dey I,Szollár L,Horányi M,Magócsi M,Harsányi V,Farkas T

更新日期：1995-01-03 00:00:00

abstract：:Ischemia and reperfusion both contribute to tissue damage after myocardial infarction. Although many drugs have been shown to reduce infarct size when administered before ischemia, few have been shown to be effective when administered at reperfusion. Moreover, although it is generally accepted that a burst of reactive...

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

authors： Granville DJ,Tashakkor B,Takeuchi C,Gustafsson AB,Huang C,Sayen MR,Wentworth P Jr,Yeager M,Gottlieb RA

更新日期：2004-02-03 00:00:00

abstract：:Pheromone biosynthesis-activating neuropeptide (PBAN) regulates sex pheromone biosynthesis in female Helicoverpa (Heliothis) zea. Two oligonucleotide probes representing two overlapping amino acid regions of PBAN were used to screen 2.5 x 10(5) recombinant plaques, and a positive recombinant clone was isolated. Sequen...

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

authors： Davis MT,Vakharia VN,Henry J,Kempe TG,Raina AK

更新日期：1992-01-01 00:00:00

abstract：:Somatic mutation and neoplastic transformation of diploid Syrian hamster embryo cells were examined concomitantly. Mutations induced by benzo[a]pyrene and N-methyl-N'-nitro-N-nitrosoguanidine were quantitated at the hypoxanthine phosphoribosyltransferase and Na(+)/K(+) ATPase loci and compared to phenotypic transforma...

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

authors： Barrett JC,Ts'o PO

更新日期：1978-07-01 00:00:00

abstract：:Biogeochemical reactions occur unevenly in space and time, but this heterogeneity is often simplified as a linear average due to sparse data, especially in subsurface environments where access is limited. For example, little is known about the spatial variability of groundwater denitrification, an important process in...

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

authors： Kolbe T,de Dreuzy JR,Abbott BW,Aquilina L,Babey T,Green CT,Fleckenstein JH,Labasque T,Laverman AM,Marçais J,Peiffer S,Thomas Z,Pinay G

更新日期：2019-02-12 00:00:00

abstract：:We have isolated lentivirus strains that are related to the human immunodeficiency virus (HIV) from African green monkeys (Cercopithecus aethiops; AGM). Although immunologically related, these SIVagm are clearly distinct from other simian immunodeficiency virus (SIV) isolates, including isolates from Macaca mulatta (S...

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

authors： Kraus G,Werner A,Baier M,Binniger D,Ferdinand FJ,Norley S,Kurth R

更新日期：1989-04-01 00:00:00

abstract：:Although much of the brain's functional organization is genetically predetermined, it appears that some noninnate functions can come to depend on dedicated and segregated neural tissue. In this paper, we describe a series of experiments that have investigated the neural development and organization of one such noninna...

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

authors： Polk TA,Farah MJ

更新日期：1998-02-03 00:00:00

abstract：:The 14-3-3 family of phosphoserine/threonine-recognition proteins engage multiple nodes in signaling networks that control diverse physiological and pathophysiological functions and have emerged as promising therapeutic targets for such diseases as cancer and neurodegenerative disorders. Thus, small molecule modulator...

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

authors： Zhao J,Du Y,Horton JR,Upadhyay AK,Lou B,Bai Y,Zhang X,Du L,Li M,Wang B,Zhang L,Barbieri JT,Khuri FR,Cheng X,Fu H

更新日期：2011-09-27 00:00:00

abstract：:Accounting for enzyme-mediated active sliding, disassembly, and sequence-dependent positioning of nucleosomes, we simulate nucleosome occupancy over cell-cycle-scale times using a stochastic kinetic model. We show that ATP-dependent active nucleosome sliding and nucleosome removal processes are essential to obtain in ...

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

authors： Padinhateeri R,Marko JF

更新日期：2011-05-10 00:00:00

abstract：:Insects have diversified through more than 450 million y of Earth's changeable climate, yet rapidly shifting patterns of temperature and precipitation now pose novel challenges as they combine with decades of other anthropogenic stressors including the conversion and degradation of land. Here, we consider how insects ...

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

authors： Halsch CA,Shapiro AM,Fordyce JA,Nice CC,Thorne JH,Waetjen DP,Forister ML

更新日期：2021-01-12 00:00:00

abstract：:Changes in climate during the 20th century differ from region to region across the United States. We provide strong evidence that spatial variations in US temperature trends are linked to the hydrologic cycle, and we also present unique information on the seasonal and latitudinal structure of the linkage. We show that...

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

authors： Portmann RW,Solomon S,Hegerl GC

更新日期：2009-05-05 00:00:00

abstract：:Recent studies of human disease and transgenic animal experiments have clearly demonstrated the importance of desmosomes in normal tissue architecture. Furthermore, desmosomal components are down-regulated in certain types of carcinomas, suggesting a possible role for desmosomes in suppression of invasion and metastas...

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

authors： Tselepis C,Chidgey M,North A,Garrod D

更新日期：1998-07-07 00:00:00

abstract：:Recent epidemiological studies indicate beneficial effects of moderate ethanol consumption in ischemic heart disease. Most studies, however, focus on the effect of long-term consumption of ethanol. In this study, we determined whether brief exposure to ethanol immediately before ischemia also produces cardioprotection...

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

authors： Chen CH,Gray MO,Mochly-Rosen D

更新日期：1999-10-26 00:00:00

abstract：:An electron microscopic study of somatic hybrids resulting from a cross between hamster melanoma cells harboring R-type particles and mouse fibroblasts harboring intracisternal A-type and (mostly) immature C-type particles was performed. The major findings are: (a) hybrid cells that retain a large fraction of both ham...

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

authors： Yotsuyanagi Y,Ephrussi B

更新日期：1974-11-01 00:00:00