Oxygen isotopes in tree rings are a good proxy for Amazon precipitation and El Nino-Southern Oscillation variability.

abstract：:Earlier studies have shown that the DNA of herpes simplex virus 1 consists of two covalently linked components, L and S, each flanked by inverted repeats. The two components can invert, and viral DNA extracted from infected cells or virions consists of equimolar concentrations of four populations differing solely in t...

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

authors： Poffenberger KL,Tabares E,Roizman B

更新日期：1983-05-01 00:00:00

abstract：:Regulation of the sterol-synthesizing mevalonate pathway occurs in part through feedback-regulated endoplasmic reticulum degradation of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-R). In yeast, the Hmg2p isozyme of HMG-R is regulated in this manner. We have tested the involvement of ubiquitination in the regulated d...

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

authors： Hampton RY,Bhakta H

更新日期：1997-11-25 00:00:00

abstract：:When Sertoli cells of the seminiferous epithelium in the testis were cultured on Matrigel (a reconstituted basement membrane), laminin, or one of the biologically active laminin-derived peptides (YIGSR, SIKVAV, or RGD), they exhibited dramatic changes in morphology accompanied by changes in protein secretion and gene ...

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

authors： Papadopoulos V,Dym M

更新日期：1994-07-19 00:00:00

abstract：:Alzheimer's disease (AD) is an irreversible neurodegenerative disorder that has a progression that is closely associated with oxidative stress. It has long been speculated that the reactive oxygen species (ROS) level in AD brains is much higher than that in healthy brains. However, evidence from living beings is scarc...

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

authors： Yang J,Zhang X,Yuan P,Yang J,Xu Y,Grutzendler J,Shao Y,Moore A,Ran C

更新日期：2017-11-21 00:00:00

abstract：:Many current treatments for the reclamation of contaminated water sources are chemical-intensive, energy-intensive, and/or require posttreatment due to unwanted by-product formation. We demonstrate that through the integration of nanostructured materials, enzymatic catalysis, and iron-catalyzed free radical reactions ...

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

authors： Lewis SR,Datta S,Gui M,Coker EL,Huggins FE,Daunert S,Bachas L,Bhattacharyya D

更新日期：2011-05-24 00:00:00

abstract：:During heat shock, structural changes in proteins and membranes may lead to cell death. While GroE and other chaperone proteins are involved in the prevention of stress-induced protein aggregation and in the recovery of protein structures, a mechanism for short-term membrane stabilization during stress remains to be e...

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

authors： Török Z,Horváth I,Goloubinoff P,Kovács E,Glatz A,Balogh G,Vígh L

更新日期：1997-03-18 00:00:00

abstract：:The 1H NMR signal from oxymyoglobin, a low-concentration diamagnetic protein, is visible in myocardial tissue. The methyl group of the Val-E11 resonates in a clear spectral region at -2.76 ppm and responds to dynamic changes in cellular oxygenation. With CO, the signal shifts to -2.4 ppm. The Val-E11 peak assignment a...

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

authors： Kreutzer U,Wang DS,Jue T

更新日期：1992-05-15 00:00:00

abstract：:Although much evidence suggests that the plasma membrane of eukaryotic cells is not homogenous, the precise architecture of this important structure has not been clear. Here we use transmission electron microscopy of plasma membrane sheets and specific probes to show that most or all plasma membrane-associated protein...

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

authors： Lillemeier BF,Pfeiffer JR,Surviladze Z,Wilson BS,Davis MM

更新日期：2006-12-12 00:00:00

abstract：:Phalloidin, a toxic bicyclic peptide of rapid action from the toadstool, Amanita phalloides, gives rise to polymerization of G-actin to filamentous structures (Ph-actin) in a medium of low ionic strength. Ph-actin closely resembles the microfilaments found in liver membrane fractions (Ph-filaments) after in vivo or in...

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

authors： Lengsfeld AM,Löw I,Wieland T,Dancker P,Hasselbach W

更新日期：1974-07-01 00:00:00

abstract：:Little is known about stem cell biology or the specialized environments or niches believed to control stem cell renewal and differentiation in self-renewing tissues of the body. Functional assays for stem cells are available only for hematopoiesis and spermatogenesis, and the microenvironment, or niche, for hematopoie...

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

authors： Shinohara T,Orwig KE,Avarbock MR,Brinster RL

更新日期：2001-05-22 00:00:00

abstract：:Six Rhesus monkeys between 24 and 29 years of age received unilateral transections of the fornix. Three monkeys then received intraventricular transplants of polymer-encapsulated baby hamster kidney (BHK) fibroblasts that had been genetically modified to secrete human nerve growth factor (hNGF). The remaining three mo...

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

authors： Kordower JH,Winn SR,Liu YT,Mufson EJ,Sladek JR Jr,Hammang JP,Baetge EE,Emerich DF

更新日期：1994-11-08 00:00:00

abstract：:Many cancers have substantial genomic heterogeneity within a given tumor, and to fully understand that diversity requires the ability to perform single cell analysis. We performed targeted sequencing of a panel of single nucleotide variants (SNVs), deletions, and IgH sequences in 1,479 single tumor cells from six acut...

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

authors： Gawad C,Koh W,Quake SR

更新日期：2014-12-16 00:00:00

abstract：:Injection of rat kidney cortex mRNA into Xenopus laevis oocytes leads to a stimulation of Na(+)-dependent SO4(2-) uptake. Based on this information, we have isolated from a corresponding library a cDNA (NaSi-1) that is most likely related to a Na+/SO4(2-) cotransport system. NaSi-1 cRNA leads in a time- and dose-depen...

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

authors： Markovich D,Forgo J,Stange G,Biber J,Murer H

更新日期：1993-09-01 00:00:00

abstract：:Four monoclonal anti-parathyroid antibodies were generated after immunization of mice with intact cells from human parathyroid tissue. All four monoclonal antibodies reacted in immunohistochemistry with structures present on parathyroid epithelial cells and proximal-tubule cells of the kidney but were unreactive with ...

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

authors： Juhlin C,Holmdahl R,Johansson H,Rastad J,Akerström G,Klareskog L

更新日期：1987-05-01 00:00:00

abstract：:Gold nanoparticles (NPs) wrapped in a membrane can be utilized as artificial virus nanoparticles (AVNs) that combine the large nonblinking or bleaching optical cross-section of the NP core with the biological surface properties and functionalities provided by a self-assembled lipid membrane. We used these hybrid nanom...

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

authors： Xu F,Bandara A,Akiyama H,Eshaghi B,Stelter D,Keyes T,Straub JE,Gummuluru S,Reinhard BM

更新日期：2018-09-25 00:00:00

abstract：:Proteasome activator PA200 enhances proteasome-mediated cleavage after acidic residues in vitro; however, its role within cells is not known. Here, we show that, in response to ionizing radiation, PA200 forms hybrid proteasomes with 19S caps and 20S core proteasomes that accumulate on chromatin, leading to an increase...

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

authors： Blickwedehl J,Agarwal M,Seong C,Pandita RK,Melendy T,Sung P,Pandita TK,Bangia N

更新日期：2008-10-21 00:00:00

abstract：:Cell-specific activation of the transcription factor sigma F during sporulation in Bacillus subtilis is controlled by a regulatory pathway involving the proteins SpoIIE, SpoIIAA, and SpoIIAB. SpoIIAB is an antagonist of sigma F, and SpoIIAA, which is capable of overcoming SpoIIAB-mediated inhibition of sigma F, is an ...

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

authors： Arigoni F,Duncan L,Alper S,Losick R,Stragier P

更新日期：1996-04-16 00:00:00

abstract：:The GroE chaperonins assist substrate protein (SP) folding by cycling through several conformational states. With each cycle the SP is, in turn, captured, unfolded, briefly encapsulated (t1/2 ∼ 1 s), and released by the chaperonin complex. The protein-folding functional form is the US-football-shaped GroEL:GroES2 comp...

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

authors： Fei X,Ye X,LaRonde NA,Lorimer GH

更新日期：2014-09-02 00:00:00

abstract：:The ability to infect macrophages is a common characteristic shared among many mycobacterial species. Mycobacterium avium, Mycobacterium tuberculosis, and Mycobacterium kansasii enter macrophages, using the complement receptors CR1, CR3, CR4, and the mannose receptor. To identify M. avium genes and host cell pathways ...

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

authors： Danelishvili L,Wu M,Stang B,Harriff M,Cirillo SL,Cirillo JD,Bildfell R,Arbogast B,Bermudez LE

更新日期：2007-06-26 00:00:00

abstract：:Double fertilization is a key innovation for the evolutionary success of angiosperms by which the two fertilized female gametes, the egg cell and central cell, generate the embryo and endosperm, respectively. The female gametophyte (embryo sac) enclosed in the sporophyte is derived from a one-celled haploid cell linea...

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

authors： Zhang MX,Zhu SS,Xu YC,Guo YL,Yang WC,Li HJ

更新日期：2020-03-17 00:00:00

abstract：:Barth, Larsen, and others showed that complex submanifolds of complex projective space, CP(N), of small codimension strongly resemble CP(N) both homotopically and cohomologically. These results are generalized to yield analogous results for complex subspaces of arbitrary homogeneous complex manifolds. One very special...

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

authors： Sommese AJ

更新日期：1977-04-01 00:00:00

abstract：:An 125I-labeled synthetic analog of bovine parathyroid hormone, [8-norleucine,18-norleucine,34-tyrosine]PTH-(1-34) amide ([Nle]PTH-(1-34)-NH2), purified by high-pressure liquid chromatography (HPLC), was employed to label the parathyroid hormone (PTH) receptor in cell lines derived from PTH target tissues: the ROS 17/...

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

authors： Wright BS,Tyler GA,O'Brien R,Caporale LH,Rosenblatt M

更新日期：1987-01-01 00:00:00

abstract：:The gene IL-3 encodes interleukin 3, a hematopoietic colony-stimulating factor (CSF) that is capable of supporting the proliferation of a broad range of hematopoietic cell types. By using somatic cell hybrids and in situ chromosomal hybridization, we localized this gene to human chromosome 5 at bands q23-31, a chromos...

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

authors： Le Beau MM,Epstein ND,O'Brien SJ,Nienhuis AW,Yang YC,Clark SC,Rowley JD

更新日期：1987-08-01 00:00:00

abstract：:Cysteine site-directed mutagenesis was used to create variants of Escherichia coli ribosomal protein L7/L12 that have single cysteine substitutions, at residues 63 or 89, located in different exposed loops in the structure of the globular C-terminal domain indicated by the crystallographic structure. That structure sh...

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

authors： Oleinikov AV,Jokhadze GG,Traut RR

更新日期：1993-11-01 00:00:00

abstract：:Field cancerization predisposes the upper aerodigestive tract mucosa to the formation of multiple primary tumors, when exposed to environmental carcinogens. Up-regulation of epidermal growth factor receptor occurs early in squamous cell carcinogenesis and is critical for the loss of growth control in a variety of huma...

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

authors： Grandis JR,Drenning SD,Zeng Q,Watkins SC,Melhem MF,Endo S,Johnson DE,Huang L,He Y,Kim JD

更新日期：2000-04-11 00:00:00

abstract：:Inflammation is a hallmark of many diseases, such as atherosclerosis, chronic obstructive pulmonary disease, arthritis, infectious diseases, and cancer. Although steroids and cyclooxygenase inhibitors are effective antiinflammatory therapeutical agents, they may cause serious side effects. Therefore, developing unique...

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

authors： Jeon KI,Xu X,Aizawa T,Lim JH,Jono H,Kwon DS,Abe J,Berk BC,Li JD,Yan C

更新日期：2010-05-25 00:00:00

abstract：:Broken-cell preparations of Salmonella typhimurium rapidly incorporated 75Se from 75SeO3(2-) into tRNA by an ATP-dependent process. Selenium incorporation in the presence of 50 microM 75SeO3(2-) (0.8-1 pmol per A260 unit) was enhanced by the selenocysteine precursor, O-acetyl-L-serine (to 3.7 pmol per A260 unit). This...

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

authors： Veres Z,Tsai L,Politino M,Stadtman TC

更新日期：1990-08-01 00:00:00

abstract：:The role of intraspecific and interspecific interactions in structuring biotic communities at fine spatial scales is well documented, but the signature of species interactions at coarser spatial scales is unclear. We present evidence that species interactions may be a significant factor in mediating the regional assem...

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

authors： Gotelli NJ,Graves GR,Rahbek C

更新日期：2010-03-16 00:00:00

abstract：:In the present article we describe the design and evaluation of a synthetic receptor that binds to the exterior surface of chymotrypsin and disrupts its interaction with proteinaceous inhibitors, such as soybean trypsin inhibitor, basic pancreatic trypsin inhibitor, ovomucoid turkey inhibitor, and Bowman-Birk inhibito...

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

authors： Park HS,Lin Q,Hamilton AD

更新日期：2002-04-16 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