The frequency of gene targeting in yeast depends on the number of target copies.

abstract：:The ability of the isolated perfused rat liver to differentiate between chylomicrons and remnants with either high or low apoprotein E:C ratios was investigated. Remnants were prepared in hepatectomized rats injected with chylomicrons double-labeled with [3H]cholesterol and 14C-labeled fatty acids. By densitometric sc...

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

authors： Borensztajn J,Kotlar TJ

更新日期：1984-09-01 00:00:00

abstract：:Shigella sonnei is a human-adapted pathogen that is emerging globally as the dominant agent of bacterial dysentery. To investigate local establishment, we sequenced the genomes of 263 Vietnamese S. sonnei isolated over 15 y. Our data show that S. sonnei was introduced into Vietnam in the 1980s and has undergone locali...

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

authors： Holt KE,Thieu Nga TV,Thanh DP,Vinh H,Kim DW,Vu Tra MP,Campbell JI,Hoang NV,Vinh NT,Minh PV,Thuy CT,Nga TT,Thompson C,Dung TT,Nhu NT,Vinh PV,Tuyet PT,Phuc HL,Lien NT,Phu BD,Ai NT,Tien NM,Dong N,Parry CM,Hie

更新日期：2013-10-22 00:00:00

abstract：:We synthesized a series of octapeptide analogs of somatostatin, containing N-terminal tryptophan or another amino acid followed by the hexapeptide sequences Cys-Phe-D-Trp-Lys-Thr-Cys or Cys-Tyr-D-Trp-Lys-Val-Cys and a C-terminal threoninamide or tryptophanamide. After purification by HPLC, the inhibitory activities of...

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

authors： Cai RZ,Karashima T,Guoth J,Szoke B,Olsen D,Schally AV

更新日期：1987-04-01 00:00:00

abstract：:A renin promoter-large tumor antigen (T antigen) fusion gene was constructed to provide a reporter function for renin expression in transgenic mice. These transgenic mice gave rise to tumors in subcutaneous soft tissue, which was attributed to transgene expression at this site. An immunohistochemical analysis of trans...

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

authors： Sigmund CD,Jones CA,Mullins JJ,Kim U,Gross KW

更新日期：1990-10-01 00:00:00

abstract：:Epidemiological and genetic association studies show that genetics play an important role in the attainment of education. Here, we investigate the effect of this genetic component on the reproductive history of 109,120 Icelanders and the consequent impact on the gene pool over time. We show that an educational attainm...

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

authors： Kong A,Frigge ML,Thorleifsson G,Stefansson H,Young AI,Zink F,Jonsdottir GA,Okbay A,Sulem P,Masson G,Gudbjartsson DF,Helgason A,Bjornsdottir G,Thorsteinsdottir U,Stefansson K

更新日期：2017-01-31 00:00:00

abstract：:Most new genes are thought to evolve from preexisting genes but duplications of entire genes or shuffling of preexisting exons provides only a limited repertoire of new sequences that can be presented to a cell. Only pieces that previously existed can be used in the construction and any further divergence depends on t...

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

authors： Golding GB,Tsao N,Pearlman RE

更新日期：1994-08-02 00:00:00

abstract：:Many neurodegenerative diseases are characterized by the accumulation of amyloid fibers in the brain, which can occur when a protein misfolds into an extended beta-sheet conformation. The nucleation of these beta-sheet aggregates is of particular interest, not only because it is the rate-determining step toward fiber ...

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

authors： Petty SA,Decatur SM

更新日期：2005-10-04 00:00:00

abstract：:Numerous studies have shown that high olive oil intake reduces blood pressure (BP). These positive effects of olive oil have frequently been ascribed to its minor components, such as alpha-tocopherol, polyphenols, and other phenolic compounds that are not present in other oils. However, in this study we demonstrate th...

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

authors： Terés S,Barceló-Coblijn G,Benet M,Alvarez R,Bressani R,Halver JE,Escribá PV

更新日期：2008-09-16 00:00:00

abstract：:We find that histidine residues in proteins are major targets for reaction with the lipid peroxidation product 4-hydroxynon-2-enal (HNE). Reaction of insulin (which contains no sulfhydryl groups) with HNE leads to the generation of HNE-protein adducts, which are converted to radioactive derivatives upon subsequent tre...

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

authors： Uchida K,Stadtman ER

更新日期：1992-05-15 00:00:00

abstract：:We have investigated whether the large (5- to 15-fold) stimulation of synthesis of growth hormone (somatotropin) observed upon exposure of a strain of rat pituitary (GH3) cells to dexamethasone (a synthetic glucocorticoid) arises from a stimulation of pregrowth hormone mRNA. A good agreement was observed between the s...

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

authors： Tushinski RJ,Sussman PM,Yu LY,Bancroft FC

更新日期：1977-06-01 00:00:00

abstract：:Of all the myosin filaments in muscle, the most important in terms of human health, and so far the least studied, are those in the human heart. Here we report a 3D single-particle analysis of electron micrograph images of negatively stained myosin filaments isolated from human cardiac muscle in the normal (undiseased)...

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

authors： Al-Khayat HA,Kensler RW,Squire JM,Marston SB,Morris EP

更新日期：2013-01-02 00:00:00

abstract：:Measures of complexity derived from ergodic theory of dynamical systems were developed and applied to an exemplary data set describing locomotor movements of rats in a bounded space. A symbolic dynamical system was obtained by partitioning the event space into equally probable partition elements, using a k-dimensional...

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

authors： Paulus MP,Geyer MA,Gold LH,Mandell AJ

更新日期：1990-01-01 00:00:00

abstract：:Escherichia coli peptide chain release factors are proteins that direct the termination of translation in response to specific peptide chain termination codons. The mechanisms of codon recognition and peptidyl-tRNA hydrolysis are unknown. We have characterized the genes encoding release factor 1 (RF-1) and release fac...

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

authors： Craigen WJ,Cook RG,Tate WP,Caskey CT

更新日期：1985-06-01 00:00:00

abstract：:The Hippo-YAP/TAZ signaling pathway plays a pivotal role in growth control during development and regeneration and its dysregulation is widely implicated in various cancers. To further understand the cellular and molecular mechanisms underlying Hippo signaling regulation, we have found that activities of core Hippo si...

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

authors： Kim W,Cho YS,Wang X,Park O,Ma X,Kim H,Gan W,Jho EH,Cha B,Jeung YJ,Zhang L,Gao B,Wei W,Jiang J,Chung KS,Yang Y

更新日期：2019-05-07 00:00:00

abstract：:As the Copenhagen Accord indicates, most of the international community agrees that global mean temperature should not be allowed to rise more than two degrees Celsius above preindustrial levels to avoid unacceptable damages from climate change. The scientific evidence distilled in the Fourth Assessment Report of the ...

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

authors： Heitzig J,Lessmann K,Zou Y

更新日期：2011-09-20 00:00:00

abstract：:Bruton tyrosine kinase (EC 2.7.1.112) [Btk, encoded by Btk in mice and BTK in humans (formerly known as atk, BPK, or emb)], which is variously mutated in chromosome X-linked agammaglobulinemia patients and X-linked immunodeficient (xid) mice, has the pleckstrin homology (PH) domain at its amino terminus. The PH domain...

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

authors： Yao L,Kawakami Y,Kawakami T

更新日期：1994-09-13 00:00:00

abstract：:We found that two markers of differentiation, tyrosinase (monophenol, dihydroxyphenylalanine:oxygen oxidoreductase, EC 1.14.18.1) activity and melanin synthesis, are induced by diazepam in B16/C3 mouse melanoma cells. We also demonstrated high-affinity binding sites for [3H]diazepam in these cells by radioreceptor ass...

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

authors： Matthew E,Laskin JD,Zimmerman EA,Weinstein IB,Hsu KC,Engelhardt DL

更新日期：1981-06-01 00:00:00

abstract：:We investigated the structural and functional alterations of active lamellae during initial cell-cell collision and establishment of cell-cell contacts in wounded cultures of nontransformed rat epitheliocytes (IAR-2 line) and their ras-transformed descendants (C4 line). Typically, the leading edges of nontransformed c...

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

authors： Gloushankova NA,Alieva NA,Krendel MF,Bonder EM,Feder HH,Vasiliev JM,Gelfand IM

更新日期：1997-02-04 00:00:00

abstract：:Many chemoattractants cause chemotaxis of leukocytes by stimulating a structurally distinct class of G protein-coupled receptors. To identify receptor functions required for chemotaxis, we studied chemotaxis in HEK293 cells transfected with receptors for nonchemokine ligands or for interleukin 8 (IL-8), a classical ch...

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

authors： Neptune ER,Bourne HR

更新日期：1997-12-23 00:00:00

abstract：:Glial fibrillary acidic protein (GFAP) is a member of the family of intermediate filament structural proteins and is found predominantly in astrocytes of the central nervous system (CNS). To assess the function of GFAP, we created GFAP-null mice using gene targeting in embryonic stem cells. The GFAP-null mice have nor...

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

authors： McCall MA,Gregg RG,Behringer RR,Brenner M,Delaney CL,Galbreath EJ,Zhang CL,Pearce RA,Chiu SY,Messing A

更新日期：1996-06-25 00:00:00

abstract：:Cell proliferation may be altered in many diseases, but it is uncertain exactly how to measure total numbers of divisions. Although it is impossible to count every division directly, potentially total numbers of stem cell divisions since birth may be inferred from numbers of somatic errors. The idea is that divisions ...

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

authors： Kim JY,Tavaré S,Shibata D

更新日期：2005-12-06 00:00:00

abstract：:Our understanding of the molecular control of many disease pathologies requires the identification of direct substrates targeted by specific protein kinases. Here we describe an integrated proteomic strategy, termed kinase assay linked with phosphoproteomics, which combines a sensitive kinase reaction with endogenous ...

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

authors： Xue L,Wang WH,Iliuk A,Hu L,Galan JA,Yu S,Hans M,Geahlen RL,Tao WA

更新日期：2012-04-10 00:00:00

abstract：:The molecular and cellular basis of selective motor neuron (MN) vulnerability in amyotrophic lateral sclerosis (ALS) is not known. In genetically distinct mouse models of familial ALS expressing mutant superoxide dismutase-1 (SOD1), TAR DNA-binding protein 43 (TDP-43), and fused in sarcoma (FUS), we demonstrate select...

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

authors： Lalancette-Hebert M,Sharma A,Lyashchenko AK,Shneider NA

更新日期：2016-12-20 00:00:00

abstract：:Hoxb13 is robustly transcribed in derivatives of posterior endoderm including the colon, rectum, and the prostate gland. Transcriptional activity in the prostate persists unabated under conditions of androgen deprivation and throughout the course of disease progression in a mouse prostate cancer model. To elucidate th...

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

authors： McMullin RP,Dobi A,Mutton LN,Orosz A,Maheshwari S,Shashikant CS,Bieberich CJ

更新日期：2010-01-05 00:00:00

abstract：:The sudden appearance of calcified skeletons among many different invertebrate taxa at the Precambrian-Cambrian transition may have required minor reorganization of preexisting secretory functions. In particular, features of the skeletal organic matrix responsible for regulating crystal growth by inhibition may be der...

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

authors： Marin F,Smith M,Isa Y,Muyzer G,Westbroek P

更新日期：1996-02-20 00:00:00

abstract：:Groups of subjects with different degrees of glucose intolerance were examined in order to determine, first, the capacity of the beta cells to release insulin upon glucose stimulation and, second, sensitivity to insulin. The groups were selected on the basis of fasting blood glucose value and tolerances to oral and in...

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

authors： Efendić S,Wajngot A,Cerasi E,Luft R

更新日期：1980-12-01 00:00:00

abstract：:An enzymatic activity, having the properties expected of a B-specific host-controlled modification enzyme, has been purified from an extract of Escherichia coli strain B. This activity renders the unmodified replicative form of phage fd resistant to B-specific restriction and is only present in strains carrying intact...

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

authors： Kühnlein U,Linn S,Arber W

更新日期：1969-06-01 00:00:00

abstract：:Perception and cognition in infants have been traditionally investigated using habituation paradigms, assuming that babies' memories in laboratory contexts are best constructed after numerous repetitions of the very same stimulus in the absence of interference. A crucial, yet open, question regards how babies deal wit...

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

authors： Benavides-Varela S,Siugzdaite R,Gómez DM,Macagno F,Cattarossi L,Mehler J

更新日期：2017-07-18 00:00:00

abstract：:Art forgeries have existed since antiquity, but with the recent rapidly expanding commercialization of art, the approach to art authentication has demanded increasingly sophisticated detection schemes. So far, the most conclusive criterion in the field of counterfeit detection is the scientific proof of material anach...

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

authors： Hendriks L,Hajdas I,Ferreira ESB,Scherrer NC,Zumbühl S,Smith GD,Welte C,Wacker L,Synal HA,Günther D

更新日期：2019-07-02 00:00:00

abstract：:Recent studies investigating the relationship between crop genetic diversity and human cultural diversity patterns showed that seed exchanges are embedded in farmers' social organization. However, our understanding of the social processes involved remains limited. We investigated how farmers' membership in three major...

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

authors： Labeyrie V,Thomas M,Muthamia ZK,Leclerc C

更新日期：2016-01-05 00:00:00