Viscosity of α-pinene secondary organic material and implications for particle growth and reactivity.

abstract：:The major obstacle to the study of functional/structural interrelationships of spinach chloroplasts by using spin labels has been the rapid loss of the electron paramagnetic resonance (EPR) signals upon illumination with visible light. The present study demonstrates that the addition of ferredoxin and NADP+ in the pre...

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

authors： Sun AS,Calvin M

更新日期：1975-08-01 00:00:00

abstract：:We have found that phagocytic leukocytes exposed to the tumor-promoting agent, 12-O-tetradecanoyl phorbol-13-acetate, efficiently release carbon-1 of 2-deoxyglucose in the form of CO2 with concurrent intracellular accumulation of a phosphorylated 5-carbon intermediate. In the absence of 12-O-tetradecanoyl phorbol-13-a...

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

authors： Zabos P,Kyner D,Mendelsohn N,Schreiber C,Waxman S,Christman J,Acs G

更新日期：1978-11-01 00:00:00

abstract：:Creatine kinase from rabbit muscle has been specifically labeled with a derivative of a nitroxide free radical on the two essential sulfhydryl groups, one per active site. The conformation in the environment of the enzyme-bound free radical and the change in conformation induced upon binding of the substrate, metal ad...

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

authors： Taylor JS,Leigh JS Jr,Cohn M

更新日期：1969-09-01 00:00:00

abstract：:The question was addressed whether the risk of cancer of an individual in a heterogeneous population can be predicted on the basis of measurable biochemical and biological variables postulated to be associated with the process of chemical carcinogenesis. Using the skin tumor model with outbred male NMRI mice, the late...

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

authors： Fischer WH,Lutz WK

更新日期：1995-06-20 00:00:00

abstract：:Transport of L-glutamine and of the chloroketone glutamine analog L-2-amino-4-oxo-5-chloropentanoate into lymphoid cells is mediated by the same system. Arginine and a number of other amino acids (e.g., glutamate, aspartate, and lysine) are transported to a much lesser extent by this system. However, after uptake of t...

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

authors： Novogrodsky A,Nehring RE Jr,Meister A

更新日期：1979-10-01 00:00:00

abstract：:PIK3R2 encodes a ubiquitous regulatory subunit (p85β) of PI3K, an enzyme that generates 3-polyphosphoinositides at the plasma membrane. PI3K activation triggers cell survival and migration. We found that p85β expression is elevated in breast and colon carcinomas and that its increased expression correlates with PI3K p...

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

authors： Cortés I,Sánchez-Ruíz J,Zuluaga S,Calvanese V,Marqués M,Hernández C,Rivera T,Kremer L,González-García A,Carrera AC

更新日期：2012-07-10 00:00:00

abstract：:It is possible, by using Fourier-transform infrared (FTIR) difference spectroscopy, to detect the conformational changes occurring in both the protein and the chromophore of bacteriorhodopsin during the photocycle. In contrast to Raman spectroscopy, a laser is unnecessary and hence the problem of a perturbing probe be...

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

authors： Rothschild KJ,Marrero H

更新日期：1982-07-01 00:00:00

abstract：:The bright ultrafast pulses of X-ray Free-Electron Lasers allow investigation into the structure of matter under extreme conditions. We have used single pulses to ionize and probe water as it undergoes a phase transition from liquid to plasma. We report changes in the structure of liquid water on a femtosecond time sc...

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

authors： Beyerlein KR,Jönsson HO,Alonso-Mori R,Aquila A,Bajt S,Barty A,Bean R,Koglin JE,Messerschmidt M,Ragazzon D,Sokaras D,Williams GJ,Hau-Riege S,Boutet S,Chapman HN,Tîmneanu N,Caleman C

更新日期：2018-05-29 00:00:00

abstract：:The binding of bovine TSH (thyroid stimulating hormone), LH (luteinizing hormone), and their subunits to the TSH receptor of beef thyroid membranes was compared to stimulation by these agents of adenylate cyclase [ATP pyrophosphate-lyase(cyelizing), EC 4.6.1.1] in the same membranes, glucose oxidation in dog thyroid s...

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

authors： Wolff J,Winand RJ,Kohn LD

更新日期：1974-09-01 00:00:00

abstract：:Chronic stress is known to promote inflammatory bowel disease (IBD), but the underlying mechanism remains largely unresolved. Here, we found chronic stress to sensitize mice to dextran sulfate sodium (DSS)-induced colitis; to increase the infiltration of B cells, neutrophils, and proinflammatory ly6Chi macrophages in ...

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

authors： Gao X,Cao Q,Cheng Y,Zhao D,Wang Z,Yang H,Wu Q,You L,Wang Y,Lin Y,Li X,Wang Y,Bian JS,Sun D,Kong L,Birnbaumer L,Yang Y

更新日期：2018-03-27 00:00:00

abstract：:Administration of gamma-glutamylcysteinylglycyl monomethyl (or monoethyl) ester to mice leads to substantial increases in the levels of glutathione in the liver and kidney. Mice depleted of glutathione by treatment with buthionine sulfoximine, a potent inhibitor of gamma-glutamylcysteine synthetase, exhibited about a ...

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

authors： Puri RN,Meister A

更新日期：1983-09-01 00:00:00

abstract：:Sleep is essential for basic survival, and insufficient sleep leads to a variety of dysfunctions. In humans, one of the most profound consequences of sleep deprivation is imprecise or irrational communication, demonstrated by degradation in signaling as well as in receiving information. Communication in nonhuman anima...

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

authors： Klein BA,Klein A,Wray MK,Mueller UG,Seeley TD

更新日期：2010-12-28 00:00:00

abstract：:ATP-sensitive potassium (KATP) channels in the pancreatic beta cell membrane mediate insulin release in response to elevation of plasma glucose levels. They are open at rest but close in response to glucose metabolism, producing a depolarization that stimulates Ca2+ influx and exocytosis. Metabolic regulation of KATP ...

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

authors： Gribble FM,Tucker SJ,Haug T,Ashcroft FM

更新日期：1998-06-09 00:00:00

abstract：:Clostridium difficile, a causative agent of antibiotic-associated diarrhea and its potentially lethal form, pseudomembranous colitis, produces two large protein toxins that are responsible for the cellular damage associated with the disease. The level of toxin production appears to be critical for determining the seve...

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

authors： Mani N,Dupuy B

更新日期：2001-05-08 00:00:00

abstract：:The phase transition for turbulent diffusion, reported by Avellaneda and Majda [Avellaneda, M. & Majda, A. J. (1994) Philos. Trans. R. Soc. London A 346, 205-233, and several earlier papers], is traced to a modeling assumption in which the energy spectrum of the turbulent fluid is singularly dependent on the viscosity...

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

authors： Wallstrom TC

更新日期：1995-11-21 00:00:00

abstract：:Cell-based therapies are attractive for revascularizing and regenerating tissues and organs, but clinical trials of endothelial progenitor cell transplantation have not resulted in consistent benefit. We propose a different approach in which a material delivery system is used to create a depot of vascular progenitor c...

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

authors： Silva EA,Kim ES,Kong HJ,Mooney DJ

更新日期：2008-09-23 00:00:00

abstract：:Adaptive behavior requires animals to learn from experience. Ideally, learning should both promote choices that lead to rewards and reduce choices that lead to losses. Because the ventral striatum (VS) contains neurons that respond to aversive stimuli and aversive stimuli can drive dopamine release in the VS, it is po...

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

authors： Taswell CA,Costa VD,Murray EA,Averbeck BB

更新日期：2018-12-26 00:00:00

abstract：:Nerve growth factor (NGF) serum levels were measured in 49 patients with asthma and/or rhinoconjunctivitis and/or urticaria-angioedema. Clinical and biochemical parameters, such as bronchial reactivity, total and specific serum IgE levels, and circulating eosinophil cationic protein levels, were evaluated in relation ...

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

authors： Bonini S,Lambiase A,Bonini S,Angelucci F,Magrini L,Manni L,Aloe L

更新日期：1996-10-01 00:00:00

abstract：:In myocardial ischemia, adrenergic nerves release excessive amounts of norepinephrine (NE), causing dysfunction and arrhythmias. With anoxia and the concomitant ATP depletion, vesicular storage of NE is impaired, resulting in accumulation of free NE in the axoplasm of sympathetic nerves. Intraneuronal acidosis activat...

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

authors： Silver RB,Mackins CJ,Smith NC,Koritchneva IL,Lefkowitz K,Lovenberg TW,Levi R

更新日期：2001-02-27 00:00:00

abstract：:The major late transcriptional unit of adenovirus type 2 has served as a model for studying transcription in eukaryotes. We report that pausing and premature termination are intrinsic to the transcription of this transcriptional unit by RNA polymerase II. In vivo and in isolated nuclei, transcription pauses at discret...

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

authors： Maderious A,Chen-Kiang S

更新日期：1984-10-01 00:00:00

abstract：:The plant Mentzelia pumila (family Loasaceae) has leaves and stems densely covered with tiny hooked trichomes. The structures entrap and kill insects and therefore are most probably protective. But they are also maladaptive in that they incapacitate a coccinellid beetle (Hippodamia convergens) that preys upon an aphid...

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

authors： Eisner T,Eisner M,Hoebeke ER

更新日期：1998-04-14 00:00:00

abstract：:The tissue-specific pattern of mRNA expression can indicate important clues about gene function. High-density oligonucleotide arrays offer the opportunity to examine patterns of gene expression on a genome scale. Toward this end, we have designed custom arrays that interrogate the expression of the vast majority of pr...

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

authors： Su AI,Wiltshire T,Batalov S,Lapp H,Ching KA,Block D,Zhang J,Soden R,Hayakawa M,Kreiman G,Cooke MP,Walker JR,Hogenesch JB

更新日期：2004-04-20 00:00:00

abstract：:Reinforcement learning models now provide principled guides for a wide range of reward learning experiments in animals and humans. One key learning (error) signal in these models is experiential and reports ongoing temporal differences between expected and experienced reward. However, these same abstract learning mode...

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

authors： Lohrenz T,McCabe K,Camerer CF,Montague PR

更新日期：2007-05-29 00:00:00

abstract：:Nutrition recommendations worldwide emphasize ingestion of plant-based diets rather than diets that rely primarily on animal products. However, this plant-based diet could limit the intake of essential nutrients such as calcium. Osteoporosis is one of the world's most prevalent nutritional disorders, and inadequate di...

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

authors： Morris J,Hawthorne KM,Hotze T,Abrams SA,Hirschi KD

更新日期：2008-02-05 00:00:00

abstract：:We have isolated, cloned, and expressed a male antennae-specific pheromone-degrading enzyme (PDE) [Antheraea polyphemus PDE (ApolPDE), formerly known as Sensillar Esterase] from the wild silkmoth, A. polyphemus, which seems essential for the rapid inactivation of pheromone during flight. The onset of enzymatic activit...

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

authors： Ishida Y,Leal WS

更新日期：2005-09-27 00:00:00

abstract：:A single catalytic site model is proposed to account for the multiphasic kinetics of oxidation of ferrocytochrome c by cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1). This model involves nonproductive binding of substrate to sites near the catalytic site on cytochrome c oxidase for cytochro...

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

authors： Speck SH,Dye D,Margoliash E

更新日期：1984-01-01 00:00:00

abstract：:Antibiotic-resistant isolates of Salmonella enterica were selected on plates containing lethal concentrations of rifampicin, kanamycin, and nalidixic acid. The stability of the resistance phenotype was scored after nonselective growth. Rifampicin-resistant (Rif(r)) isolates were stable, suggesting that they had arisen...

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

authors： Sánchez-Romero MA,Casadesús J

更新日期：2014-01-07 00:00:00

abstract：:Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unp...

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

authors： Komatsu KJ,Avolio ML,Lemoine NP,Isbell F,Grman E,Houseman GR,Koerner SE,Johnson DS,Wilcox KR,Alatalo JM,Anderson JP,Aerts R,Baer SG,Baldwin AH,Bates J,Beierkuhnlein C,Belote RT,Blair J,Bloor JMG,Bohlen PJ,Bork EW

更新日期：2019-09-03 00:00:00

abstract：:In addition to tRNA and 5S RNA, Escherichia coli contains several other small, stable RNA species; these are M1, 10Sa, 6S, and 4.5S RNA. Although these RNAs are initially synthesized as precursor molecules, relatively little is known about their maturation. The data presented here show that 3' exoribonucleolytic trimm...

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

authors： Li Z,Pandit S,Deutscher MP

更新日期：1998-03-17 00:00:00

abstract：:The excitatory neurotransmitter, glutamate, activates N-methyl-d-aspartate (NMDA) receptors to induce long-lasting synaptic changes through alterations in gene expression. It is believed that these long-lasting changes contribute to learning and memory, drug tolerance, and ischemic preconditioning. To identify NMDA-in...

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

authors： Hong SJ,Li H,Becker KG,Dawson VL,Dawson TM

更新日期：2004-02-17 00:00:00