Polyploid megakaryocytes develop randomly from a multicompartmental system of committed progenitors.

abstract：:Chromosomal instability (CIN) is a defining characteristic of most human cancers. Mutation of CIN genes increases the probability that whole chromosomes or large fractions of chromosomes are gained or lost during cell division. The consequence of CIN is an imbalance in the number of chromosomes per cell (aneuploidy) a...

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

authors： Nowak MA,Komarova NL,Sengupta A,Jallepalli PV,Shih IeM,Vogelstein B,Lengauer C

更新日期：2002-12-10 00:00:00

abstract：:We have examined the process by which small groups of pigmented germinal cells transplanted orthotopically from stage 30-38 donor embryos into stage 28-38 albino hosts contribute new postmitotic cells to the pigmented retinal epithelium of the growing larval eye in Xenopus. In the great majority of chimeric eyes, the ...

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

authors： Hunt RK,Cohen JS,Mason BJ

更新日期：1987-05-01 00:00:00

abstract：:Across North America, human activities have been shown to cause river incision into unconsolidated alluvium. Human-caused erosion through bedrock, however, has only been observed in local and isolated outcrops. Here, we test whether splash-dam logging, which decreased in-stream alluvial cover by removing much of the a...

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

authors： Schanz SA,Montgomery DR,Collins BD

更新日期：2019-04-30 00:00:00

abstract：:We have constructed a phylogenic tree for green plants by comparing 5S rRNA sequences. The tree suggests that the emergence of most of the uni- and multicellular green algae such as Chlamydomonas, Spirogyra, Ulva, and Chlorella occurred in the early stage of green plant evolution. The branching point of Nitella is a l...

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

authors： Hori H,Lim BL,Osawa S

更新日期：1985-02-01 00:00:00

abstract：:We have long known that language is lateralized to the left hemisphere (LH) in most neurologically healthy adults. In contrast, findings on lateralization of function during development are more complex. As in adults, anatomical, electrophysiological, and neuroimaging studies in infants and children indicate LH latera...

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

authors： Olulade OA,Seydell-Greenwald A,Chambers CE,Turkeltaub PE,Dromerick AW,Berl MM,Gaillard WD,Newport EL

更新日期：2020-09-22 00:00:00

abstract：:Glutamyl-tRNA (Glu-tRNA), formed by Glu-tRNA synthetase (GluRS), is a substrate for protein biosynthesis and tetrapyrrole formation by the C(5) pathway. In this route Glu-tRNA is transformed to delta-aminolevulinic acid, the universal precursor of tetrapyrroles (e.g., heme and chlorophyll) by the action of Glu-tRNA re...

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

authors： Levicán G,Katz A,de Armas M,Núñez H,Orellana O

更新日期：2007-02-27 00:00:00

abstract：:The single-pass transmembrane domains (TMDs) of the syndecan family of cell surface adhesion molecules have been implicated in functional protein-protein interactions. Although each paralog contains a conserved GxxxG dimerization motif, we show here that the syndecan-1 TMD dimerizes weakly, the syndecan-3 and syndecan...

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

authors： Dews IC,Mackenzie KR

更新日期：2007-12-26 00:00:00

abstract：:Intergroup conflict is a persistent feature of many human societies yet little is known about why individuals participate when doing so imposes a mortality risk. To evaluate whether participation in warfare is associated with reproductive benefits, we present data on participation in small-scale livestock raids among ...

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

authors： Glowacki L,Wrangham R

更新日期：2015-01-13 00:00:00

abstract：:The amino acid sequence of the light chain of bovine protein C was determined by sequenator analysis of the carboxymethylated light chain and fragments obtained by cyanogen bromide treatment, tryptic digestion after blocking of lysine residues, and cleavage with 2-(2-nitrophenylsulfenyl)-3-methyl-3-bromoindolenine (BN...

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

authors： Fernlund P,Stenflo J,Tufvesson A

更新日期：1978-12-01 00:00:00

abstract：:The great mass extinctions of the fossil record were a major creative force that provided entirely new kinds of opportunities for the subsequent explosive evolution and diversification of surviving clades. Today, the synergistic effects of human impacts are laying the groundwork for a comparably great Anthropocene mas...

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

authors： Jackson JB

更新日期：2008-08-12 00:00:00

abstract：:NRSF/REST is a protein that silences transcription of a number of genes that contain a DNA element called the neuron-restrictive silencer element (NRSE). During embryogenesis, REST is expressed ubiquitously in nonneural cells, but is down-regulated during differentiation of neural progenitors into neurons. REST is als...

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

authors： Koenigsberger C,Chicca JJ 2nd,Amoureux MC,Edelman GM,Jones FS

更新日期：2000-02-29 00:00:00

abstract：:The presence of an amino acid other than aspartic acid at position 57 of the HLA-DQ beta chain (non-Asp-57) is highly associated with susceptibility to insulin-dependent diabetes mellitus (IDDM), whereas an aspartic acid at this position (Asp-57) appears to confer resistance to the disease. We hypothesize that the 30-...

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

authors： Dorman JS,LaPorte RE,Stone RA,Trucco M

更新日期：1990-10-01 00:00:00

abstract：:Genetic data in the mouse have shown that endothelin 3 (ET3) and its receptor B (ETRB) are essential for the development of two neural crest (NC) derivatives, the melanocytes and the enteric nervous system. We report here the effects of ET3 in vitro on the differentiation of quail trunk NC cells (NCC) in mass and clon...

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

authors： Lahav R,Dupin E,Lecoin L,Glavieux C,Champeval D,Ziller C,Le Douarin NM

更新日期：1998-11-24 00:00:00

abstract：:African sleeping sickness is a fatal disease that is caused by the protozoan parasite Trypanosoma brucei. Polyamine biosynthesis is an essential pathway in the parasite and is a validated drug target for treatment of the disease. S-adenosylmethionine decarboxylase (AdoMetDC) catalyzes a key step in polyamine biosynthe...

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

authors： Willert EK,Fitzpatrick R,Phillips MA

更新日期：2007-05-15 00:00:00

abstract：:The role of chemotaxis in the virulence of gastrointestinal pathogens is ill defined. Counterintuitively, nonchemotactic mutants of the polarly flagellated pathogen Vibrio cholerae greatly out-compete the wild-type strain during infection of the small intestine. We show that the out-competition phenotype is dependent ...

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

authors： Butler SM,Camilli A

更新日期：2004-04-06 00:00:00

abstract：:Differential scanning microcalorimetry provides a noninvasive method for studying heat evolution in living cells. We used this technique to measure the heat evolved by thioglycollate broth-elicited mouse macrophages, and the effects of NaF, KCN, cycloheximide, and cytochalasins B and D on this parameter. The total hea...

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

authors： Loike JD,Silverstein SC,Sturtevant JM

更新日期：1981-10-01 00:00:00

abstract：:The maintenance of robust blood flow to the brain is crucial to the health of brain tissue. We examined the pial network of the middle cerebral artery, which distributes blood from the cerebral arteries to the penetrating arterioles that source neocortical microvasculature, to characterize how vascular topology may su...

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

authors： Blinder P,Shih AY,Rafie C,Kleinfeld D

更新日期：2010-07-13 00:00:00

abstract：:The dynamics of excited-state double proton transfer of model DNA base pairs, 7-azaindole dimers, is reported using femtosecond fluorescence spectroscopy. To elucidate the nature of the transfer in the condensed phase, here we examine variation of solvent polarity and viscosity, solute concentration, and isotopic frac...

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

authors： Kwon OH,Zewail AH

更新日期：2007-05-22 00:00:00

abstract：:Incubation of a human beta-globin pre-mRNA in a HeLa cell nuclear extract under conditions permissive for efficient splicing resulted in the assembly of the RNA into ribonucleoprotein (RNP) complexes. This RNP formation occurred largely within the characteristic lag period that precedes splicing. Two classes of RNP we...

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

authors： Mayrand SH,Pedersen N,Pederson T

更新日期：1986-06-01 00:00:00

abstract：:The non-long terminal repeat (LTR) retrotransposon, R2, encodes a sequence-specific endonuclease responsible for its insertion at a unique site in the 28S rRNA genes of arthropods. Although most non-LTR retrotransposons encode an apurinic-like endonuclease upstream of a common reverse transcriptase domain, R2 and many...

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

authors： Yang J,Malik HS,Eickbush TH

更新日期：1999-07-06 00:00:00

abstract：:The 2012-2015 drought has left California with severely reduced snowpack, soil moisture, ground water, and reservoir stocks, but the impact of this estimated millennial-scale event on forest health is unknown. We used airborne laser-guided spectroscopy and satellite-based models to assess losses in canopy water conten...

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

authors： Asner GP,Brodrick PG,Anderson CB,Vaughn N,Knapp DE,Martin RE

更新日期：2016-01-12 00:00:00

abstract：:A major barrier to the design of immunotherapeutics and vaccines for cancer is the idiosyncratic nature of many tumor antigens and the possibility that T cells may be tolerant of broadly distributed antigens. We have devised an experimental strategy that exploits species differences in protein sequences to circumvent ...

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

authors： Theobald M,Biggs J,Dittmer D,Levine AJ,Sherman LA

更新日期：1995-12-19 00:00:00

abstract：:In recent years, considerable progress has been made in understanding the molecular mechanisms underlying olfaction in insects. Because of the diverse nature of the gene families involved, this process has largely relied on genomic data. As a consequence, studies have focused on a small subset of species with extensiv...

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

authors： Grosse-Wilde E,Kuebler LS,Bucks S,Vogel H,Wicher D,Hansson BS

更新日期：2011-05-03 00:00:00

abstract：:Fluorescence of quinacrine in the presence of different polynucleotides was studied to attempt to identify the specific nucleotides responsible for the fluorescence of stained chromosome preparations. A marked enhancement of fluorescence was seen in the presence of bihelical polynucleotides, such as poly(dA-dT), poly(...

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

authors： Weisblum B,De Haseth PL

更新日期：1972-03-01 00:00:00

abstract：:Eradication of an invasive species can provide significant environmental, economic, and social benefits, but eradication programs often fail. Constant and careful monitoring improves the chance of success, but an invasion may seem to be in decline even when it is expanding in abundance or spatial extent. Determining w...

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

authors： Keith JM,Spring D

更新日期：2013-08-13 00:00:00

abstract：:Bone marrow mononuclear cells (BMC) from patients with ischemic cardiomyopathy (ICMP) show a reduced neovascularization capacity in vivo. NO plays an important role in neovascularization, and NO bioavailability is typically reduced in patients with ICMP. We investigated whether the impaired neovascularization capacity...

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

authors： Sasaki K,Heeschen C,Aicher A,Ziebart T,Honold J,Urbich C,Rossig L,Koehl U,Koyanagi M,Mohamed A,Brandes RP,Martin H,Zeiher AM,Dimmeler S

更新日期：2006-09-26 00:00:00

abstract：:Hermansky-Pudlak syndrome (HPS) defines a group of autosomal recessive disorders characterized by deficiencies in lysosome-related organelles such as melanosomes and platelet-dense granules. Several HPS genes encode proteins of unknown function including HPS1, HPS3, and HPS4. Here we have identified and characterized ...

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

authors： Nazarian R,Falcón-Pérez JM,Dell'Angelica EC

更新日期：2003-07-22 00:00:00

abstract：:The generation of toxic oligomers during the aggregation of the amyloid-β (Aβ) peptide Aβ42 into amyloid fibrils and plaques has emerged as a central feature of the onset and progression of Alzheimer's disease, but the molecular pathways that control pathological aggregation have proved challenging to identify. Here, ...

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

authors： Cohen SI,Linse S,Luheshi LM,Hellstrand E,White DA,Rajah L,Otzen DE,Vendruscolo M,Dobson CM,Knowles TP

更新日期：2013-06-11 00:00:00

abstract：:The main sources of information regarding ancient Mesopotamian history and culture are clay cuneiform tablets. Many of these tablets are damaged, leading to missing information. Currently, the missing text is manually reconstructed by experts. We investigate the possibility of assisting scholars, by modeling the langu...

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

authors： Fetaya E,Lifshitz Y,Aaron E,Gordin S

更新日期：2020-09-15 00:00:00

abstract：:Endocrine therapy resistance invariably develops in advanced estrogen receptor-positive (ER+) breast cancer, but the underlying mechanisms are largely unknown. We have identified C-terminal SRC kinase (CSK) as a critical node in a previously unappreciated negative feedback loop that limits the efficacy of current ER-t...

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

authors： Xiao T,Li W,Wang X,Xu H,Yang J,Wu Q,Huang Y,Geradts J,Jiang P,Fei T,Chi D,Zang C,Liao Q,Rennhack J,Andrechek E,Li N,Detre S,Dowsett M,Jeselsohn RM,Liu XS,Brown M

更新日期：2018-07-31 00:00:00