Immunological significance of Mycobacterium leprae cell walls.

abstract：:Mahler proved the following quantitative result supplementing the Lindemann-Weierstrass theorem: Sigma(i=0) (n)C(i)e(ri) > H(-n-epsilon) for any distinct rational numbers r(0),r(1),..., r(n) and rational integers C(0),C(1),...,C(n) with H = max(0

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

authors： Chudnovsky GV

更新日期：1983-05-01 00:00:00

abstract：:Archaea of the phylum Thaumarchaeota are among the most abundant prokaryotes on Earth and are widely distributed in marine, terrestrial, and geothermal environments. All studied Thaumarchaeota couple the oxidation of ammonia at extremely low concentrations with carbon fixation. As the predominant nitrifiers in the oce...

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

authors： Könneke M,Schubert DM,Brown PC,Hügler M,Standfest S,Schwander T,Schada von Borzyskowski L,Erb TJ,Stahl DA,Berg IA

更新日期：2014-06-03 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：:We have investigated the regulation of the expression of two growth factors found in vascular smooth muscle, transforming growth factor alpha (TGF alpha) and basic fibroblast growth factor (bFGF). Cells cultured in medium containing 30 mM glucose exhibited a 2-fold increase in TGF alpha mRNA and a 3-fold increase in b...

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

authors： McClain DA,Paterson AJ,Roos MD,Wei X,Kudlow JE

更新日期：1992-09-01 00:00:00

abstract：:Integral feedback control is a basic engineering strategy for ensuring that the output of a system robustly tracks its desired value independent of noise or variations in system parameters. In biological systems, it is common for the response to an extracellular stimulus to return to its prestimulus value even in the ...

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

authors： Yi TM,Huang Y,Simon MI,Doyle J

更新日期：2000-04-25 00:00:00

abstract：:A discrepancy is explored regarding the spin exchange integral estimated from magnetic field effects on recombination of the bacteriochlorophyll dimer cation (Bchl)(2)+ and the bacteriopheophytin anion Bph(-) and the measured electron transfer rate between Bph and electronically excited (Bchl)(2). In one explanation c...

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

authors： Haberkorn R,Michel-Beyerle ME,Marcus RA

更新日期：1979-09-01 00:00:00

abstract：:Metazoan embryogenesis is controlled by a limited number of signaling modules that are used repetitively at successive developmental stages. The development of social amoebas shows similar reiterated use of cAMP-mediated signaling. In the model Dictyostelium discoideum, secreted cAMP acting on 4 cAMP receptors (cARs1-...

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

authors： Kawabe Y,Morio T,James JL,Prescott AR,Tanaka Y,Schaap P

更新日期：2009-04-28 00:00:00

abstract：:Many groups of insects are specialists in exploiting sensory cues to locate food resources or conspecifics. To achieve orientation, bees and ants analyze the polarization pattern of the sky, male moths orient along the females' odor plume, and cicadas, grasshoppers, and crickets use acoustic signals to locate singing ...

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

authors： Poulet JF,Hedwig B

更新日期：2005-10-25 00:00:00

abstract：:Nonhuman primates possess a highly developed capacity for face recognition, which resembles the human capacity both cognitively and neurologically. Face recognition is typically tested by having subjects compare facial images, whereas there has been virtually no attention to how they connect these images to reality. C...

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

authors： Pokorny JJ,de Waal FB

更新日期：2009-12-22 00:00:00

abstract：:Priming of cytotoxic T lymphocytes (CTLs) by dendritic cells (DCs) is crucial for elimination of pathogens and malignant cells. To activate CTLs, DCs present antigenic peptide-complexed MHC class I molecules (MHC-I) that will be recognized by the CTLs with T cell receptors and CD8 molecules. Here we show that paired I...

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

authors： Endo S,Sakamoto Y,Kobayashi E,Nakamura A,Takai T

更新日期：2008-09-23 00:00:00

abstract：:The human Thy-1 gene has been isolated and sequenced and compared to the rat and mouse Thy-1 genes. All three genes are organized in the same way: one exon encoding the majority of the signal peptide, another encoding the transmembrane segment, and a third encoding the remainder of the protein. One major structural di...

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

authors： Seki T,Spurr N,Obata F,Goyert S,Goodfellow P,Silver J

更新日期：1985-10-01 00:00:00

abstract：:The functional capacities of CD8(+) T cells important for virus clearance are influenced by interactions with antigen presenting cells (APCs) and CD4(+) T cells during initial selection, subsequent expansion, and development of memory. Recently, investigators have shown that polyfunctional T cells correlate best with ...

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

authors： Ndhlovu ZM,Oelke M,Schneck JP,Griffin DE

更新日期：2010-02-23 00:00:00

abstract：:Tropical diversity has generally exceeded temperate diversity in the present and at points in the past, but whether measured differences have remained relatively constant through time has been unknown. Here we examine tropical vs. temperate diversities from the Neogene to Recent using the within-habitat diversity meas...

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

authors： Buzas MA,Collins LS,Culver SJ

更新日期：2002-06-11 00:00:00

abstract：:Herpes simplex virus 1 (HSV-1) specifies in the infected cell a set of polypeptides (alpha) whose mRNAs are made in the absence of protein synthesis. The individual mRNAs specifying alpha polypeptides 0, 4, 22, and 27 were purified by hybridization to strand-separated or total HSV-1 DNA fragments cloned in pBR322 plas...

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

authors： Mackem S,Roizman B

更新日期：1980-12-01 00:00:00

abstract：:Saccharomyces cerevisiae strains expressing the activated RAS2Val19 gene or lacking both cAMP phosphodiesterase genes, PDE1 and PDE2, have impaired growth control and display an acute sensitivity to heat shock. We have isolated two classes of mammalian cDNAs from yeast expression libraries that suppress the heat shock...

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

authors： Colicelli J,Nicolette C,Birchmeier C,Rodgers L,Riggs M,Wigler M

更新日期：1991-04-01 00:00:00

abstract：:The elevation of Ca2+ levels in the cytoplasm inactivates inward-rectifying K+ channels that play a central role in regulating the apertures of stomatal pores in higher plants. However, the mechanism for the Ca(2+)-mediated inhibition of K(+)-channel function is unknown. Using patch-clamp techniques, we show that cycl...

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

authors： Luan S,Li W,Rusnak F,Assmann SM,Schreiber SL

更新日期：1993-03-15 00:00:00

abstract：:Posttranslational modification is an important element in circadian clock function from cyanobacteria through plants and mammals. For example, a number of key clock components are phosphorylated and thereby marked for subsequent ubiquitination and degradation. Through forward genetic analysis we demonstrate that prote...

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

authors： Hong S,Song HR,Lutz K,Kerstetter RA,Michael TP,McClung CR

更新日期：2010-12-07 00:00:00

abstract：:Existing moral psychology research commonly explains certain phenomena in terms of a motivation to blame. However, this motivation is not measured directly, but rather is inferred from other measures, such as participants' judgments of an agent's blameworthiness. The present paper introduces new methods for assessing ...

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

authors： Ames DL,Fiske ST

更新日期：2015-03-24 00:00:00

abstract：:The fractionation of cells of a parsley suspension culture [Petroselinum crispum (Mill.) A. Hill] by protoplasting and subsequent removal of the vacuoles led to physiologically intact evacuolated protoplasts retaining light inducibility of chalcone synthase expression. Lysis of the evacuolated protoplasts permitted th...

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

authors： Harter K,Frohnmeyer H,Kircher S,Kunkel T,Mühlbauer S,Schäfer E

更新日期：1994-05-24 00:00:00

abstract：:The heat-stable enterotoxin B (STB) of Escherichia coli is a 48-amino acid extracellular peptide that induces rapid fluid accumulation in animal intestinal models. Unlike other E. coli enterotoxins that elicit cAMP or cGMP responses in the gut [heat-labile toxin (LT) and heat-stable toxin A (STA), respectively], STB i...

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

authors： Dreyfus LA,Harville B,Howard DE,Shaban R,Beatty DM,Morris SJ

更新日期：1993-04-15 00:00:00

abstract：:Public responses where identical T cell receptors (TCRs) are clonally dominant and shared between different individuals are a common characteristic of CD8(+) T cell-mediated immunity. Focusing on TCR sharing, we analyzed approximately 3,400 TCR beta chains (TCRbetas) from mouse CD8(+) T cells responding to the influen...

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

authors： Venturi V,Kedzierska K,Price DA,Doherty PC,Douek DC,Turner SJ,Davenport MP

更新日期：2006-12-05 00:00:00

abstract：:Axiomatic foundations for a theory of perception have been given in a prior communication [Shiman, L. G. (1978) Proc. Natl. Acad. Sci. USA 75, 2049-2053]. The theory is based on mathematically characterized stable images. Stable images model subjective (psychological) states of observers. We showed there is a universa...

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

authors： Shiman LG

更新日期：1978-05-01 00:00:00

abstract：:The small heat-shock protein (sHSP) from Methanococcus jannaschii (Mj HSP16.5) forms a homomeric complex of 24 subunits and has an overall structure of a multiwindowed hollow sphere with an external diameter of approximately 120 A and an internal diameter of approximately 65 A with six square "windows" of approximatel...

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

authors： Kim R,Lai L,Lee HH,Cheong GW,Kim KK,Wu Z,Yokota H,Marqusee S,Kim SH

更新日期：2003-07-08 00:00:00

abstract：:We describe here the successful establishment of a reverse genetics system for rotavirus (RV), a member of the Reoviridae family whose genome consists of 10-12 segmented dsRNA. The system is based on the recombinant vaccinia virus T7 RNA polymerase-driven procedure for supplying artificial viral mRNA in the cytoplasm....

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

authors： Komoto S,Sasaki J,Taniguchi K

更新日期：2006-03-21 00:00:00

abstract：:Although Hedgehog (Hh) signaling regulates cell differentiation during pancreas organogenesis, the consequences of pathway up-regulation in adult β-cells in vivo have not been investigated. Here, we elevate Hh signaling in β-cells by expressing an active version of the GLI2 transcription factor, a mediator of the Hh p...

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

authors： Landsman L,Parent A,Hebrok M

更新日期：2011-10-11 00:00:00

abstract：:We have used a microfluidic mass sensor to measure the density of single living cells. By weighing each cell in two fluids of different densities, our technique measures the single-cell mass, volume, and density of approximately 500 cells per hour with a density precision of 0.001 g mL(-1). We observe that the intrins...

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

authors： Grover WH,Bryan AK,Diez-Silva M,Suresh S,Higgins JM,Manalis SR

更新日期：2011-07-05 00:00:00

abstract：:Thyrotoxicosis increases endogenous glucose production (EGP) and induces hepatic insulin resistance. We have recently shown that these alterations can be modulated by selective hepatic sympathetic and parasympathetic denervation, pointing to neurally mediated effects of thyroid hormone on glucose metabolism. Here, we ...

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

authors： Klieverik LP,Janssen SF,van Riel A,Foppen E,Bisschop PH,Serlie MJ,Boelen A,Ackermans MT,Sauerwein HP,Fliers E,Kalsbeek A

更新日期：2009-04-07 00:00:00

abstract：:The fossil record of land plants is an obvious source of information on the dynamics of mass extinctions in the geological past. In conjunction with the end-Permian ecological crisis, approximately 250 million years ago, palynological data from East Greenland reveal some unanticipated patterns. We document the signifi...

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

authors： Looy CV,Twitchett RJ,Dilcher DL,Van Konijnenburg-Van Cittert JH,Visscher H

更新日期：2001-07-03 00:00:00

abstract：:Previous work has shown that the kinetoplast minicircle DNA of Leishmania species exhibits species-specific sequence divergence and this observation has led to the development of a DNA probe-based diagnostic test for leishmaniasis. In the work reported here, we demonstrate that the minicircle is composed of three type...

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

authors： Rogers WO,Wirth DF

更新日期：1987-01-01 00:00:00

abstract：:Breast tumors lacking expression of human epidermal growth factor receptor 2 (HER2) and the estrogen and the progesterone receptors (triple negative; TNBC) are more aggressive than other disease subtypes, and no molecular targeted agents are currently available for their treatment. Because TNBC commonly displays EGF r...

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

authors： Ferraro DA,Gaborit N,Maron R,Cohen-Dvashi H,Porat Z,Pareja F,Lavi S,Lindzen M,Ben-Chetrit N,Sela M,Yarden Y

更新日期：2013-01-29 00:00:00