Novel free radicals in synthetic and natural pheomelanins: distinction between dopa melanins and cysteinyldopa melanins by ESR spectroscopy.

abstract：:We report an approach for the detection of magnetic resonance imaging without superconducting magnets and cryogenics: optical atomic magnetometry. This technique possesses a high sensitivity independent of the strength of the static magnetic field, extending the applicability of magnetic resonance imaging to low magne...

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

authors： Xu S,Yashchuk VV,Donaldson MH,Rochester SM,Budker D,Pines A

更新日期：2006-08-22 00:00:00

abstract：:At what range can a mammalian cell sense the presence of another cell and through what medium? To approach these questions, the formation of aggregates of a 3T3 cell variant (3T3x cells) grown on solid substrates was studied. Each of the aggregates consisted of cells that, at the time of their seeding, were single and...

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

authors： Albrecht-Buehler G

更新日期：2005-04-05 00:00:00

abstract：:Niemann-Pick type C (NPC) disease is predominantly caused by mutations in the NPC1 protein that affect intracellular cholesterol trafficking and cause accumulation of unesterified cholesterol and other lipids in lysosomal storage organelles. We report the use of a series of small molecule histone deacetylase (HDAC) in...

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

authors： Pipalia NH,Cosner CC,Huang A,Chatterjee A,Bourbon P,Farley N,Helquist P,Wiest O,Maxfield FR

更新日期：2011-04-05 00:00:00

abstract：:Increased clouds and precipitation normally decrease the diurnal temperature range (DTR) and thus have commonly been offered as explanation for the trend of reduced DTR observed for many land areas over the last several decades. Observations show, however, that the DTR was reduced most in dry regions and especially in...

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

authors： Zhou L,Dickinson RE,Tian Y,Vose RS,Dai Y

更新日期：2007-11-13 00:00:00

abstract：:The Hawaiian honeycreepers (Drepanidae) represent a superb illustration of evolutionary radiation, with a single colonization event giving rise to 19 extant and at least 10 extinct species [Curnutt, J. & Pimm, S. (2001) Stud. Avian Biol. 22, 15-30]. They also represent a dramatic example of anthropogenic extinction. C...

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

authors： Benning TL,LaPointe D,Atkinson CT,Vitousek PM

更新日期：2002-10-29 00:00:00

abstract：:The role played by oligodendrocytes (OLs), the myelinating cells of the CNS, during brain development has not been fully explored. We have addressed this question by inducing a temporal and reversible ablation of OLs on postnatal CNS development. OL ablation in newborn mice leads to a profound alteration in the struct...

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

authors： Collin L,Usiello A,Erbs E,Mathis C,Borrelli E

更新日期：2004-01-06 00:00:00

abstract：:Earlier papers demonstrated an extensive genetic exchange among fluorescent Pseudomonads; this one documents for genes specifying enzymes of peripheral dissimilation an extrachromosomal array, segregation, and frequent interstrain transfer. An hypothesis is presented of a general mechanism for the formation and mainte...

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

authors： Rheinwald JG,Chakrabarty AM,Gunsalus IC

更新日期：1973-03-01 00:00:00

abstract：:Navigation, the ability to reach desired goal locations, is critical for animals and humans. Animal navigation has been studied extensively in birds, insects, and some marine vertebrates and invertebrates, yet we are still far from elucidating the underlying mechanisms in other taxonomic groups, especially mammals. He...

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

authors： Tsoar A,Nathan R,Bartan Y,Vyssotski A,Dell'Omo G,Ulanovsky N

更新日期：2011-09-13 00:00:00

abstract：:The rates of reassociation of DNA from a monkey cell line (Vero), from SV40 pseudovirus (consisting of Vero DNA and virus protein coat), and from mature SV40 were measured. The results show that the host DNA in the pseudovirus contains repeated and unique sequences in the same proportions as normal host DNA; hence, no...

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

authors： Grady L,Axelrod D,Trilling D

更新日期：1970-12-01 00:00:00

abstract：:A goal of regenerative medicine is to identify cardiovascular progenitors from human ES cells (hESCs) that can functionally integrate into the human heart. Previous studies to evaluate the developmental potential of candidate hESC-derived progenitors have delivered these cells into murine and porcine cardiac tissue, w...

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

authors： Ardehali R,Ali SR,Inlay MA,Abilez OJ,Chen MQ,Blauwkamp TA,Yazawa M,Gong Y,Nusse R,Drukker M,Weissman IL

更新日期：2013-02-26 00:00:00

abstract：:Interleukin 3 (IL-3) is a hematopoietic growth factor that supports the proliferation and differentiation of early hematopoietic-lineage progenitors. By using growth factor-dependent cell lines, IL-3 has been shown to induce the appearance of several phosphotyrosine-containing proteins, including a 140-kDa cell surfac...

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

authors： Isfort RJ,Stevens D,May WS,Ihle JN

更新日期：1988-11-01 00:00:00

abstract：:The cellular actions of nerve growth factor (NGF) and epidermal growth factor (EGF) may be mediated by changes in protein phosphorylation. The tyrosine phosphorylation of two predominant proteins of molecular mass 40 and 42 kDa is seen in PC-12 cells treated with NGF or EGF, correlating with activation of a previously...

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

authors： Miyasaka T,Sternberg DW,Miyasaka J,Sherline P,Saltiel AR

更新日期：1991-04-01 00:00:00

abstract：:Variants of isovaleryl-CoA dehydrogenase (IVDHase, EC 1.3.99.10) in 15 isovaleric acidemia fibroblast lines were analyzed using [35S]methionine labeling, immunoprecipitation with anti-rat IVDHase antiserum, and NaDodSo4/polyacrylamide gel electrophoresis. Five distinct variants of IVDHase were detected. The molecular ...

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

authors： Ikeda Y,Keese SM,Tanaka K

更新日期：1985-10-01 00:00:00

abstract：:The nature of integrated viral DNA in normal and leukemic chicken cells has been studied by sequential nucleic acid hybridization procedures that localize the viral specific DNA in cellular DNA regions differing in reiteration frequency. First, DNA.DNA reassociation was employed to fractionate cellular DNA sequences a...

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

authors： Evans RM,Baluda MA,Shoyab M

更新日期：1974-08-01 00:00:00

abstract：:Synchronized beating of cilia on multiciliated cells (MCCs) generates a directional flow of mucus across epithelia. This motility requires a "9 + 2" microtubule (MT) configuration in axonemes and the unidirectional array of basal bodies of cilia on the MCCs. However, it is not fully understood what components are need...

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

authors： Robinson AM,Takahashi S,Brotslaw EJ,Ahmad A,Ferrer E,Procissi D,Richter CP,Cheatham MA,Mitchell BJ,Zheng J

更新日期：2020-06-16 00:00:00

abstract：:Alzheimer's disease (AD) is characterized by a progressive dysfunction of central neurons. Recent experimental evidence indicates that in the cortex, in addition to the silencing of a fraction of neurons, other neurons are hyperactive in amyloid-β (Aβ) plaque-enriched regions. However, it has remained unknown what com...

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

authors： Busche MA,Chen X,Henning HA,Reichwald J,Staufenbiel M,Sakmann B,Konnerth A

更新日期：2012-05-29 00:00:00

abstract：:Massive datasets that capture human movements and social interactions have catalyzed rapid advances in our quantitative understanding of human behavior during the past years. One important aspect affecting both areas is the critical role space plays. Indeed, growing evidence suggests both our movements and communicati...

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

authors： Deville P,Song C,Eagle N,Blondel VD,Barabási AL,Wang D

更新日期：2016-06-28 00:00:00

abstract：:Trimeric class I virus fusion proteins undergo a series of conformational rearrangements that leads to the association of C- and N-terminal heptad repeat domains in a "trimer-of-hairpins" structure, facilitating the apposition of viral and cellular membranes during fusion. This final fusion hairpin structure is sustai...

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

authors： Cianci C,Langley DR,Dischino DD,Sun Y,Yu KL,Stanley A,Roach J,Li Z,Dalterio R,Colonno R,Meanwell NA,Krystal M

更新日期：2004-10-19 00:00:00

abstract：:Tetrahymena ribozymes hold promise for repairing genetic disorders but are largely limited by their modest splicing efficiency and low production of final therapeutic proteins. Ribozyme evolution in intact living mammalian cells would greatly facilitate the discovery of new ribozyme variants with high in vivo activity...

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

authors： Hasegawa S,Jackson WC,Tsien RY,Rao J

更新日期：2003-12-09 00:00:00

abstract：:Monoamines, including dopamine (DA), have been linked to aggression in various species. However, the precise role or roles served by the amine in aggression have been difficult to define because dopaminergic systems influence many behaviors, and all can be altered by changing the function of dopaminergic neurons. In t...

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

authors： Alekseyenko OV,Chan YB,Li R,Kravitz EA

更新日期：2013-04-09 00:00:00

abstract：:Mature larvae of Sarcophaga argyrostoma fail to form puparia when kept in contact with water, but pupariate after having been subsequently exposed to dryness for 30 hr. They become increasingly more sensitive to injected ecdysone the longer the exposure to dry conditions. A second wet treatment halts the production of...

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

authors： Zdarek J,Fraenkel G

更新日期：1970-09-01 00:00:00

abstract：:Observations with the image tube scanner at the Shane 3-m telescope are combined with data obtained with the International Ultraviolet Explorer to assess the spectrum of the remarkable high-excitation planetary nebula NGC 6537. We have analyzed the spectrum of this nitrogen-rich object with the aid of the theoretical ...

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

authors： Feibelman W,Aller LH,Keyes CD,Czyzak SJ

更新日期：1985-04-01 00:00:00

abstract：:Stable isotope values of carbon (delta13C) and nitrogen (delta15N) in blood, feathers, eggshell, and bone have been used in seabird studies since the 1980s, providing a valuable source of information on diet, foraging patterns, and migratory behavior in these birds. These techniques can also be applied to fossil mater...

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

authors： Emslie SD,Patterson WP

更新日期：2007-07-10 00:00:00

abstract：:The effect of Zn2+ on a voltage-dependent, transient potassium current (IA) in acutely dissociated neurons from the suprachiasmatic nucleus was studied with the whole-cell patch-clamp technique. At micromolar concentrations, Zn2+ markedly potentiated IA activated from a holding potential of -60 mV, which is the restin...

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

authors： Huang RC,Peng YW,Yau KW

更新日期：1993-12-15 00:00:00

abstract：:Fibrocytes are collagen-type-I-producing cells that arise at low frequency from hematopoietic cells. We have analyzed in mice which leukocyte subsets are required for generation of fibrocytes and show that murine fibrocytes develop from the subpopulation of CD11b(+) CD115(+) Gr1(+) monocytes under the control of CD4(+...

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

authors： Niedermeier M,Reich B,Rodriguez Gomez M,Denzel A,Schmidbauer K,Göbel N,Talke Y,Schweda F,Mack M

更新日期：2009-10-20 00:00:00

abstract：:The primary obstacle to producing renewable fuels from lignocellulosic biomass is a plant's recalcitrance to releasing sugars bound in the cell wall. From a sample set of wood cores representing 1,100 individual undomesticated Populus trichocarpa trees, 47 extreme phenotypes were selected across measured lignin conten...

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

authors： Studer MH,DeMartini JD,Davis MF,Sykes RW,Davison B,Keller M,Tuskan GA,Wyman CE

更新日期：2011-04-12 00:00:00

abstract：:Prostate carcinoma is the second leading cause of death from malignancy in men in the United States. Prostate cancer cells express type I insulin-like growth factor receptor (IGF-IR) and prostate cancer selectively metastazises to bone, which is an environment rich in insulin-like growth factors (IGFs), thereby suppor...

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

authors： Burfeind P,Chernicky CL,Rininsland F,Ilan J,Ilan J

更新日期：1996-07-09 00:00:00

abstract：:A cDNA clone corresponding to a portion of the catalytic subunit of calmodulin (CaM)-dependent phosphoprotein phosphatase (calcineurin) was isolated from a murine brain library by expression vector immunoscreening. A beta-galactosidase fusion protein that reacted on Western blots with anti-calcineurin antibodies and b...

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

authors： Kincaid RL,Nightingale MS,Martin BM

更新日期：1988-12-01 00:00:00

abstract：:The extinction of a species is inevitably preceded by the extirpation of a series of local populations. Ecological theory predicts that vulnerability to extirpation varies between populations and is ultimately linked to environmental heterogeneity. If populations of a species are present in multiple regions separated ...

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

authors： Yackulic CB,Sanderson EW,Uriarte M

更新日期：2011-03-08 00:00:00

abstract：:Under anesthesia with sodium pentobarbital, the sciatic nerves of rats were transected bilaterally, and a catheter was inserted into the central end of the left renal artery. After an initial flush, an Alzet pump was attached to the catheter, containing various concentrations of glycyl-L-glutamine (Gly-Gln), methylpre...

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

authors： Koelle GB,Han MS

更新日期：1990-12-01 00:00:00