abstract：:Walker-256 carcinosarcoma cells grown in tissue culture medium containing inhibitory DNA prepared from the tumor are shown to have an unaltered growth in vitro, but a diminished capacity to produce malignant tumors on injection into the rat. Coincident with this change in virulence is the induction of tRNA methylase i...

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

authors： Halpern BC,Halpern RM,Chaney SQ,Smith RA

更新日期：1970-12-01 00:00:00

abstract：:In this paper we extend the well-known Vitali-Hahn-Saks and Nikodým theorems for measures to finitely additive vector-valued set functions. ...

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

authors： Brooks JK,Jewett RS

更新日期：1970-11-01 00:00:00

abstract：:Some spectinomycin-resistant mutants of Escherichia coli are cold-sensitive. They are unable to assemble both 30S and 50S ribosomal subunits at low temperatures. They accumulate two kinds of incomplete particles, related to 30S and 50S subunits respectively. A single mutation, causing an alteration in a 30S ribosomal ...

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

authors： Nashimoto H,Nomura M

更新日期：1970-11-01 00:00:00

abstract：:A temperature-sensitive ras allele has an effective lethal phase at 29 degrees C about 12 hr after pupation and a temperature-sensitive period for lethality beginning midway through the third larval instar and ending around pupation. The mutation also alters the quantity of pteridines present in the eyes, testes, and ...

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

authors： Grigliatti T,Suzuki DT

更新日期：1970-11-01 00:00:00

abstract：:Light-grown, wild type Euglena gracilis contains two aminoacyl-tRNA synthetases for both phenylalanine and isoleucine. Only one of the two synthetases for each amino acid is found in isolated chloroplasts, as are the light-induced phenylalanine and isoleucine tRNAs. In each case the light-induced chloroplast tRNAs can...

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

authors： Reger BJ,Fairfield SA,Epler JL,Barnett WE

更新日期：1970-11-01 00:00:00

abstract：:Spontaneous cross-linking in vitro, during incubation of purified collagen in nonstriated and native type fibrils, was studied to elucidate the relationship between intra and intermolecular cross-links. In nonbanded fibrils, the aldol condensation products of two allysyl residues, previously shown to constitute the in...

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

authors： Kang AH,Gross J

更新日期：1970-11-01 00:00:00

abstract：:A short, highly stereoselective (over 97%) synthesis of all-trans squalene is described. Starting with succinaldehyde, a tetraenedichlorodione having the complete squalene skeleton with the four internal trans olefinic bonds has been developed in four steps involving a sequence of two double Claisen rearrangements. Th...

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

authors： Werthemann L,Johnson WS

更新日期：1970-11-01 00:00:00

abstract：:A virus is associated with a strain of transovarially-transmitted SR-spirochetes, NSR, of Drosophila. This virus, designated spv-1, is able to infect and to multiply in another strain of SR-spirochetes, WSR, thereby eliminating the SR condition from the host flies. Spv-1 contains DNA, has a buoyant density of 1.480 in...

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

authors： Oishi K,Poulson DF

更新日期：1970-11-01 00:00:00

abstract：:We prove theorems on the structure of the fundamental group of a compact riemannian manifold of non-positive curvature. In particular, a conjecture of J. Wolf [J. Differential Geometry, 2, 421-446 (1968)] is proved. ...

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

authors： Yau ST

更新日期：1970-10-01 00:00:00

abstract：:The ganglioside pattern of both SV40- and polyoma virus-transformed mouse cell lines differs from that of the parent cell lines or of cell lines that have transformed spontaneously in tissue culture. This is manifested by a dramatic decrease of gangliosides with an oligosaccharide chain larger than sialyllactose. Pres...

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

authors： Cumar FA,Brady RO,Kolodny EH,McFarland VW,Mora PT

更新日期：1970-10-01 00:00:00

abstract：:Uniparentally inherited mutations to antibiotic resistance and dependence in Chlamydomonas reinhardi exhibit an altered chloroplast ribosome phenotype. Genetic studies demonstrate an absolute correlation between the drug resistance or dependence and the ribosome phenotype in two such mutants. ...

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

authors： Gillham NW,Boynton JE,Burkholder B

更新日期：1970-10-01 00:00:00

abstract：:The use of fluorescent probes to give continuous readouts of the structural states of mitochondrial membranes during energy coupling seems a logical extension of their use in the study of protein structural changes. A clear correlation of the probes' fluorescence characteristics with the acquisition of energy coupling...

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

authors： Chance B

更新日期：1970-10-01 00:00:00

abstract：:A study was undertaken to elucidate the molecular mechanisms by which glucocorticoids induce cleft palate in mice. It was hypothesized that a compound such as triamcinolone acetonide inhibits mRNA synthesis; that this results later in depressed protein synthesis; and that the latter is ultimately responsible for slowe...

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

authors： Zimmerman EF,Andrew F,Kalter H

更新日期：1970-10-01 00:00:00

abstract：:Phonoangiography, the quantitative analysis of sounds produced by blood flow, has been used to investigate local fluid motion in arteries narrowed by atherosclerosis. The sound spectra measured in vivo were found to be identical to those obtained in laboratory investigations of turbulent pipe flow. A theoretical model...

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

authors： Lees RS,Dewey CF Jr

更新日期：1970-10-01 00:00:00

abstract：:The phenomenon of selective translation of T4 template RNA by ribosomes from T4-infected cells, or factors derived therefrom, has been extended to studies on the initiation of protein synthesis. A high-salt extract derived from T4-infected ribosomes inhibits the formation of initiation complexes of MS2 and Escherichia...

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

authors： Klem EB,Hsu WT,Weiss SB

更新日期：1970-10-01 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：:It is suggested that differentiated embryonic cells have a high specificity of molecular constitution as regards the surface layers surrounding their cellular membranes. Correspondingly, specific interface energies may characterize the early contacts between different cell types. The question is raised whether the mor...

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

authors： Jehle H

更新日期：1970-09-01 00:00:00

abstract：:Photoperiodic control of testis growth in Passer domesticus (house sparrow) is mediated entirely by extraretinal photoreceptors in the brain. The eyes do not participate in photoperiodically significant photoreception. Removal of the pineal organ does not affect either the response to light or, to a first approximatio...

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

authors： Menaker M,Roberts R,Elliott J,Underwood H

更新日期：1970-09-01 00:00:00

abstract：:T4 polynucleotide ligase efficiently catalyzes the head-to-tail joining of the ribo-oligoadenylates, r-(pA)(8) and r-(pA)(10), in the presence of high molecular weight deoxypolythymidylate. The enzyme also catalyzes the joining of deoxy-oligothymidylates, e.g., d-(pT)(10), in the presence of ribopolyadenylate. The enz...

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

authors： Kleppe K,Van de Sande JH,Khorana HG

更新日期：1970-09-01 00:00:00

abstract：:Brief incubation of partially purified preparations of hormone-sensitive lipase from rat epididymal fat pads with ATP, Mg(++), cyclic adenosine 3':5'-monophosphate and rabbit muscle protein kinase (phosphorylase b kinase kinase) resulted in enhancement of lipolytic activity (44-93%). Little or no activation was observ...

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

authors： Huttunen JK,Steinberg D,Mayer SE

更新日期：1970-09-01 00:00:00

abstract：:The high-affinity (K(m) = 3 x 10(-8) M) transport system for histidine in Salmonella typhimurium has been resolved into three components: J, K, and P. J, which is a histidine-binding protein released by osmotic shock, is specified by the hisJ gene: hisJ mutants lack the binding protein and are defective in histidine t...

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

authors： Ames GF,Lever J

更新日期：1970-08-01 00:00:00

abstract：:Bovine proinsulin has been crystallized under a variety of conditions at both neutral and acid pH. Microtechniques were employed with sample weights of about 200 mug and volumes of 5-20 mul. The crystalline preparations all differ from each other morphologically.X-ray photographs of one form, tetragonal bipyramids gro...

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

authors： Fullerton WW,Potter R,Low BW

更新日期：1970-08-01 00:00:00

abstract：:Approximately 15 per cent of the light chains from homogeneous immunoglobulins in patients with multiple myeloma contain an oligosaccharide group. Five human myeloma light chains that contained carbohydrate were studied. The sequence Asn-[unk]-Ser/Thr was at the site of carbohydrate attachment in all light chains. The...

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

authors： Sox HC Jr,Hood L

更新日期：1970-07-01 00:00:00

abstract：:The maximum rate of expression of the lac operon is severely reduced in lac promoter mutants. Revertants of these mutations which produce higher levels of enzyme were isolated. Some of these revertants had lost sensitivity to catabolite repression and transient repression. The mutations responsible for these losses to...

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

authors： Silverstone AE,Arditti RR,Magasanik B

更新日期：1970-07-01 00:00:00

abstract：:The glycogen content of yeast rises dramatically just before the onset of the stationary phase of growth. Concomitantly, a rapid increase was found in the glucose 6-phosphate-independent (I) activity of glycogen synthetase, as well as in the total amount of enzyme. A mutant (GS 1-36) was obtained, which did not accumu...

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

authors： Rothman-Denes LB,Cabib E

更新日期：1970-07-01 00:00:00

abstract：:Previous work has shown that nuclei of young embryos (to gastrula stage) promote normal development when transplanted into enucleated eggs. As development proceeds to later stages, the nuclei become increasingly restricted in their capacity to promote normal cleavage and development, and the majority of the embryos th...

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

authors： Hennen S

更新日期：1970-07-01 00:00:00

abstract：:A model is presented for age-specific selection on the genotypes in a population. Each genotype is assigned a life table that specifies the viability and fecundity of its age classes. Breeding and reproduction occur at regular intervals, and generations overlap. Examples were generated on a digital computer. Gene freq...

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

authors： Anderson WW,King CE

更新日期：1970-07-01 00:00:00

abstract：:Subviral particles containing reovirus RNA transcriptase have been isolated from extracts of virus-infected mouse fibroblast cells. The purified particles which lacked the outer protein capsomeres of the mature virion had a buoyant density of 1.43-1.44 g/ml in CsCl and contained all of the double-stranded RNA genome o...

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

authors： Levin DH,Mendelsohn N,Schonberg M,Klett H,Silverstein S,Kapuler AM,Acs G

更新日期：1970-07-01 00:00:00

abstract：:The membrane glycoproteins specified by herpes simplex virus are synthesized concurrently with structural viral proteins and accumulate in the cytoplasm and in the membranes lining it. Analyses of free and membranebound polyribosomes, the cytoplasmic pool of soluble proteins, and purified smooth membranes showed that ...

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

authors： Spear PG,Roizman B

更新日期：1970-07-01 00:00:00

abstract：:In this paper is presented the theory of a class of locally convex lattices (L-lattices) of real functions which generalize the classical Lebesgue spaces. The monotone and dominated convergence theorems for convergence almost everywhere and sequential and order completeness of such lattices are established. These resu...

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

authors： Bogdanowicz WM

更新日期：1970-06-01 00:00:00

abstract：:Previous work indicated that the light chains of a monotypic immunoglobulins G2-K and M-K from a single patient (Ti1) are identical. Our present data show that the monotypic immunoglobulins G and M share idiotypic determinants not present in their isolated light chains or in any of a large number of other immunoglobul...

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

authors： Wang AC,Wilson KS,Hopper JE,Fudenberg HH,Nisonoff A

更新日期：1970-06-01 00:00:00

abstract：:The convulsant agent methionine sulfoximine inhibits brain glutamine synthetase irreversibly and the inhibitor becomes bound to the active site of the enzyme as methionine sulfoximine phosphate. Only one of the four isomers of methionine sulfoximine, L-methionine-S-sulfoximine, inhibits glutamine synthetase. In the pr...

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

authors： Rowe WB,Meister A

更新日期：1970-06-01 00:00:00

abstract：:Procedures are described for the isolation of conditional lethal mutants of mouse L-60T cells. The mutant lines were temperature sensitive by the following criteria: (a) colony-forming ability, (b) growth in suspension culture, and (c) rate of uptake of tritiated-thymidine. ...

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

authors： Thompson LH,Mankovitz R,Baker RM,Till JE,Siminovitch L,Whitmore GF

更新日期：1970-06-01 00:00:00

abstract：:Recent studies with fibroblasts have shown that peptidylhydroxyproline formation begins toward the end of the log phase of growth and is an expression of the activity of the enzyme, collagen proline hydroxylase, which increase in late log-phase cells. This communication reports a two- to fivefold increase in hydroxyla...

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

authors： Comstock JP,Udenfriend S

更新日期：1970-06-01 00:00:00

abstract：:The virions of vesicular stomatitis virus contain an enzyme that catalyzes the incorporation of ribonucleotides into RNA. The product of the reaction is mainly RNA complementary in base sequence to that of vesicular stomatitis virus RNA. ...

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

authors： Baltimore D,Huang AS,Stampfer M

更新日期：1970-06-01 00:00:00

abstract：:A further study is made of the intertwining operators for the representations of the simple Lie groups of real rank one. We extend and apply this to the higher rank case, obtaining various results dealing with reducibility of principal series and existence of complementary series. ...

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

authors： Knapp AW,Stein EM

更新日期：1970-05-01 00:00:00

abstract：:Sera from 11 individuals which were classified as Lp(a-) by direct gel diffusion and by absorption tests showed the presence of Lp(a) lipoprotein when the sera were concentrated 120-fold. This Lp(a) antigen was demonstrated by gel diffusion to be indistinguishable from Lp-lipoprotein isolated from known Lp(a+) sera. T...

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

authors： Harvie NR,Schultz JS

更新日期：1970-05-01 00:00:00

abstract：:A mitochondrial ribosome with an approximate sedimentation coefficient of 60 S has been isolated from the ovary of the South African clawed toad, Xenopus laevis. This ribosome is active in a submitochondrial protein-synthesizing system. It contains two species of RNA, designated as "21S" and 13S RNA, which have sequen...

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

authors： Swanson RF,Dawid IB

更新日期：1970-05-01 00:00:00

abstract：:Unit electrical activity was recorded from single neurons in the isolated lumbo-sacral spinal cord of 14- to 19-day chick embryos, in situ. Spinal cord transection was combined with transection of all lumbo-sacral dorsal roots. The spontaneous discharge of cells is confined, for the most part, to the lower two thirds ...

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

authors： Sharma SC,Provine RR,Hamburger V,Sandel TT

更新日期：1970-05-01 00:00:00

abstract：:Evidence is presented for two natural transcription initiators positioned internally in the histidine operon of Salmonella typhimurium. They were detected using highly polar S. typhimurium his mutants as recipients for F' Escherichia coli his episomes. These intergeneric complementation tests provide a sensitive metho...

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

authors： Atkins JF,Loper JC

更新日期：1970-04-01 00:00:00