Phonoangiography: a new noninvasive diagnostic method for studying arterial disease.

abstract：:The G protein-coupled m1 and m3 muscarinic acetylcholine receptors increase tyrosine phosphorylation of several proteins, including the focal adhesion-associated proteins paxillin and focal adhesion kinase (FAK), but the mechanism is not understood. Activation of integrins during adhesion of cells to extracellular mat...

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

authors： Slack BE

更新日期：1998-06-23 00:00:00

abstract：:Transmission electron microscopy studies have been used to argue that magnetite crystals in carbonate from Martian meteorite ALH84001 have a composition and morphology indistinguishable from that of magnetotactic bacteria. It has even been claimed from scanning electron microscopy imaging that some ALH84001 magnetite ...

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

authors： Weiss BP,Kim SS,Kirschvink JL,Kopp RE,Sankaran M,Kobayashi A,Komeili A

更新日期：2004-06-01 00:00:00

abstract：:The Abeta peptide of Alzheimer disease is derived from the proteolytic processing of the amyloid precursor proteins (APP), which are considered type I transmembrane glycoproteins. Recently, however, soluble forms of full-length APP were also detected in several systems including chromaffin granules. In this report we ...

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

authors： Efthimiopoulos S,Vassilacopoulou D,Ripellino JA,Tezapsidis N,Robakis NK

更新日期：1996-07-23 00:00:00

abstract：:High-quality protein crystals meant for structural analysis by X-ray diffraction have been grown by various methods. The observation of dynamical diffraction in protein crystals is an interesting topic because dynamical diffraction generally occurs in perfect crystals such as Si crystals. However, to our knowledge, th...

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

authors： Suzuki R,Koizumi H,Hirano K,Kumasaka T,Kojima K,Tachibana M

更新日期：2018-04-03 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：:Proteases constitute the largest enzyme family, yet their biological roles are obscured by our rudimentary understanding of their cellular substrates. There are 12 human caspases that play crucial roles in inflammation and cell differentiation and drive the terminal stages of cell death. Recent N-terminomics technolog...

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

authors： Julien O,Zhuang M,Wiita AP,O'Donoghue AJ,Knudsen GM,Craik CS,Wells JA

更新日期：2016-04-05 00:00:00

abstract：:The potential benefits of autonomous systems are obvious. However, there are still major issues to be dealt with before developing such systems becomes a commonplace engineering practice, with accepted and trustworthy deliverables. We argue that a solid, evolving, publicly available, community-controlled foundation fo...

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

authors： Harel D,Marron A,Sifakis J

更新日期：2020-07-28 00:00:00

abstract：:The ability of bacteria to regulate gene expression in response to changes in cell density is termed quorum sensing. This behavior involves the synthesis and recognition of extracellular, hormone-like compounds known as autoinducers. Here we report the structure of an autoinducer synthase, LuxS from Bacillus subtilis,...

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

authors： Hilgers MT,Ludwig ML

更新日期：2001-09-25 00:00:00

abstract：:The principal methyl donor of the cell, S-adenosylmethionine (SAMe), is produced by the highly conserved family of methionine adenosyltranferases (MATs) via an ATP-driven process. These enzymes play an important role in the preservation of life, and their dysregulation has been tightly linked to liver and colon cancer...

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

authors： Murray B,Antonyuk SV,Marina A,Lu SC,Mato JM,Hasnain SS,Rojas AL

更新日期：2016-02-23 00:00:00

abstract：:Three distinct forms of human alkaline phosphatase, presumably isozymes, are known, each apparently associated with a specific tissue. These are placental, intestinal, and liver (kidney and bone). We have used a specific immunoassay and HPLC to show that placental alkaline phosphatase is also present in extracts of li...

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

authors： Garattini E,Margolis J,Heimer E,Felix A,Udenfriend S

更新日期：1985-09-01 00:00:00

abstract：:T cell-mediated autoimmune diseases such as type 1 diabetes (T1D) are believed to be the result in part of inefficient negative selection of self-specific thymocytes. However, the events regulating thymic negative selection are not fully understood. In the current study, we demonstrate that nonobese diabetic (NOD) mic...

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

authors： Wallet MA,Flores RR,Wang Y,Yi Z,Kroger CJ,Mathews CE,Earp HS,Matsushima G,Wang B,Tisch R

更新日期：2009-03-24 00:00:00

abstract：:Ultrastructural immunocytochemical studies of the expression of major histocompatibility complex class I antigens in the placentas of inbred rats were performed using placentas derived from natural matings and from embryo transfers into females made pseudopregnant by mechanical stimulation. The studies utilized the WF...

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

authors： Kanbour-Shakir A,Zhang X,Rouleau A,Armstrong DT,Kunz HW,Macpherson TA,Gill TJ 3rd

更新日期：1990-01-01 00:00:00

abstract：:Permanent transfer of genetic information from chromosomes isolated from human diploid cells to recipient cells has been demonstrated. Human metaphase chromosomes were incubated with mouse A9 fibroblasts deficient in hypoxanthine phosphoribosyltransferase (IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8) and a...

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

authors： Burch JW,McBride OW

更新日期：1975-05-01 00:00:00

abstract：:Endangered species recovery programs seek to restore populations to self-sustaining levels. Nonetheless, many recovering species require continuing management to compensate for persistent threats in their environment. Judging true recovery in the face of this management is often difficult, impeding thorough analysis o...

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

authors： Finkelstein ME,Doak DF,George D,Burnett J,Brandt J,Church M,Grantham J,Smith DR

更新日期：2012-07-10 00:00:00

abstract：:The second structure of a eukaryotic RNA polymerase II so far determined, that of the enzyme from the fission yeast Schizosaccharomyces pombe, is reported here. Comparison with the previous structure of the enzyme from the budding yeast Saccharomyces cerevisiae reveals differences in regions implicated in start site s...

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

authors： Spåhr H,Calero G,Bushnell DA,Kornberg RD

更新日期：2009-06-09 00:00:00

abstract：:Cleavage of precursor proteins occurs during assembly of numerous viruses. Seven bacteriophage T4 head-related proteins areknown to be cleaved during morphogenesis. Sequences surrounding the cleavage sites in T4 head precursors P23 and IPIII are reported here. We previously determined the sequences of precursor and pr...

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

authors： Isobe T,Black LW,Tsugita A

更新日期：1976-11-01 00:00:00

abstract：:Let Lambda=SL(2)(Z) be the modular group and let c(n)(Lambda) be the number of congruence subgroups of Lambda of index at most n. We prove that lim(n--> infinity )(log c(n)(Lambda)/((log n)(2)/log log n))=(3-2(sqrt)2)/4. The proof is based on the Bombieri-Vinogradov "Riemann hypothesis on the average" and on the solut...

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

authors： Goldfeld D,Lubotzky A,Nikolov N,Pyber L

更新日期：2004-09-14 00:00:00

abstract：:The ability of beta cells to endure assaults may be relevant in the development of insulin-dependent diabetes mellitus. This study examines the susceptibility of human pancreatic islets to agents that are cytotoxic for rodent beta cells--i.e., sodium nitroprusside (NP, a nitric oxide donor), streptozotocin (SZ), or al...

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

authors： Eizirik DL,Pipeleers DG,Ling Z,Welsh N,Hellerström C,Andersson A

更新日期：1994-09-27 00:00:00

abstract：:Mouse teratocarcinoma cells induced to differentiate in vitro undergo a massive (30%) demethylation of DNA. A similar undermethylation is also observed in the mouse extraembryonic membranes, the yolk sac and placenta. In both cases, the decrease in methyl moieties occurs at a large number of CpG sites spread out over ...

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

authors： Razin A,Webb C,Szyf M,Yisraeli J,Rosenthal A,Naveh-Many T,Sciaky-Gallili N,Cedar H

更新日期：1984-04-01 00:00:00

abstract：:In early phases of human T-cell lymphotrophic virus I-induced adult T-cell leukemia (ATL), the malignant cell proliferation is associated with an autocrine process involving coordinate expression of interleukin (IL) 2 and its receptor. However, during late-phase ATL, leukemic cells no longer produce IL-2 yet continue ...

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

authors： Burton JD,Bamford RN,Peters C,Grant AJ,Kurys G,Goldman CK,Brennan J,Roessler E,Waldmann TA

更新日期：1994-05-24 00:00:00

abstract：:Patients with hematological malignancies can be successfully treated with HLA-matched T cell-depleted allogeneic stem cell transplantation (alloSCT) and subsequent donor lymphocyte infusions (DLIs). The efficacy of DLI is mediated by donor T cells recognizing minor histocompatibility antigens (mHags) on malignant reci...

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

authors： Griffioen M,van der Meijden ED,Slager EH,Honders MW,Rutten CE,van Luxemburg-Heijs SA,von dem Borne PA,van Rood JJ,Willemze R,Falkenburg JH

更新日期：2008-03-11 00:00:00

abstract：:The mechanisms regulating expression of mouse mammary tumor virus (MMTV)-encoded superantigens from the viral sag gene are largely unknown, due to problems with detection and quantification of these low-abundance proteins. To study the expression and regulation of the MMTV sag gene, we have developed a sensitive and q...

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

authors： Reuss FU,Coffin JM

更新日期：1995-09-26 00:00:00

abstract：:Degeneracy, the ability of elements that are structurally different to perform the same function or yield the same output, is a well known characteristic of the genetic code and immune systems. Here, we point out that degeneracy is a ubiquitous biological property and argue that it is a feature of complexity at geneti...

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

authors： Edelman GM,Gally JA

更新日期：2001-11-20 00:00:00

abstract：:The basidiomycete Ustilago maydis is the causative agent of the disease corn smut. To be pathogenic, strains of U. maydis must be heterozygous for a locus called "b," which appears to control both pathogenicity and sexual development. Two alleles of the b locus of U. maydis were isolated by complementation and hybridi...

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

authors： Kronstad JW,Leong SA

更新日期：1989-02-01 00:00:00

abstract：:G protein-gated inwardly rectifying potassium (GIRK) channels are critical regulators of neuronal excitability and can be directly activated by ethanol. Constitutive deletion of the GIRK3 subunit has minimal phenotypic consequences, except in response to drugs of abuse. Here we investigated how the GIRK3 subunit contr...

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

authors： Herman MA,Sidhu H,Stouffer DG,Kreifeldt M,Le D,Cates-Gatto C,Munoz MB,Roberts AJ,Parsons LH,Roberto M,Wickman K,Slesinger PA,Contet C

更新日期：2015-06-02 00:00:00

abstract：:To investigate the evolution of the mammalian sex chromosomes, we have compared the gene content of the X chromosomes in the mammalian groups most distantly related to man (marsupials and monotremes). Previous work established that genes on the long arm of the human X chromosome are conserved on the X chromosomes in a...

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

authors： Watson JM,Spencer JA,Riggs AD,Graves JA

更新日期：1991-12-15 00:00:00

abstract：:There exists a properly embedded minimal surface of genus one with a single end asymptotic to the end of the helicoid. This genus-one helicoid is constructed as the limit of a continuous one-parameter family of screw-motion invariant minimal surfaces, also asymptotic to the helicoid, that have genus equal to one in th...

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

authors： Weber M,Hoffman D,Wolf M

更新日期：2005-11-15 00:00:00

abstract：:The CD4-8- thymocyte subset contains immature precursors for phenotypically and functionally mature CD4+8- and CD4-8+ thymocytes and peripheral T cells, as well as nonmature CD4+8+ thymocytes, most of which die in situ. The intrathymic death of most thymocytes is probably related to selective influences that ensure th...

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

authors： Guidos CJ,Weissman IL,Adkins B

更新日期：1989-10-01 00:00:00

abstract：:Knowing how motile bacteria move near and along a solid surface is crucial to understanding such diverse phenomena as the migration of infectious bacteria along a catheter, biofilm growth, and the movement of bacteria through the pore spaces of saturated soil, a critical step in the in situ bioremediation of contamina...

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

authors： Frymier PD,Ford RM,Berg HC,Cummings PT

更新日期：1995-06-20 00:00:00

abstract：:The human papillomavirus E7 protein is phosphorylated at the two serines in positions 31/32, which are part of a consensus sequence for casein kinase II (CKII). In this study, we have investigated the effect of CKII phosphorylation site mutations, all of which lead to unphosphorylated E7 proteins. The replacement of t...

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

authors： Firzlaff JM,Lüscher B,Eisenman RN

更新日期：1991-06-15 00:00:00