abstract：:Fusion of myeloma cells and B lymphocytes to form hybridomas which produce monoclonal antibodies has been a major advance, but the poor efficiency and randomness of viral or polyethylene glycol fusion techniques generally gives poor yields of specific, high affinity antibodies. High voltage electrical fields with diel...

journal_title：Nature

authors： Lo MM,Tsong TY,Conrad MK,Strittmatter SM,Hester LD,Snyder SH

更新日期：1984-08-30 00:00:00

abstract：:Interchromosomal gene conversion between alleles has been shown in yeast frequently to be associated with the recombination of flanking genetic markers. Although this also holds true for gene conversion between two alleles of the yeast mating-type (MAT) locus, initiated by the homothallic switching system, we find no ...

journal_title：Nature

authors： Klar AJ,Strathern JN

更新日期：1984-08-30 00:00:00

abstract：:p60src, the transforming protein of Rous sarcoma virus (RSV), is a protein kinase that has a strict specificity for tyrosine. The phosphorylation of cellular proteins by p60src (ref. 4) results in transformation. Recently, Barker and Dayhoff discovered that residues 259-485 of p60src have 22% sequence identity with re...

journal_title：Nature

authors： Kamps MP,Taylor SS,Sefton BM

更新日期：1984-08-16 00:00:00

abstract：:Theories of the origin of optical asymmetry in living systems place fundamental importance on the amplification of optical asymmetry by an autocatalytic process. The replication of a polynucleotide is one obvious choice for such an autocatalytic growth mechanism. If an optically homogeneous polynucleotide could replic...

journal_title：Nature

authors： Joyce GF,Visser GM,van Boeckel CA,van Boom JH,Orgel LE,van Westrenen J

更新日期：1984-08-16 00:00:00

abstract：:To identify cis-acting DNA elements involved in the activation of the alpha-fetoprotein gene during differentiation, modified copies of the gene were introduced into murine F9 embryonal carcinoma cells. The differentiation of the transformants to either parietal or visceral endoderm was accompanied by induction of the...

journal_title：Nature

authors： Scott RW,Vogt TF,Croke ME,Tilghman SM

更新日期：1984-08-16 00:00:00

abstract：:The neurotransmitter dopamine has been demonstrated by biochemical, histochemical and immunocytochemical techniques to be unevenly distributed in the mammalian central nervous system. DARPP-32 (dopamine- and cyclic-AMP-regulated phosphoprotein of molecular weight 32,000) is a neuronal phosphoprotein that displays a re...

journal_title：Nature

authors： Hemmings HC Jr,Greengard P,Tung HY,Cohen P

更新日期：1984-08-09 00:00:00

abstract：:The 3-A structure of DNA-binding protein II, which exhibits histone-like properties in bacteria, has been determined. The molecule is dimeric and appears to bind to the phosphate backbone of DNA through two symmetry-related arms. A mechanism by which the protein induces DNA supercoiling is proposed. ...

journal_title：Nature

authors： Tanaka I,Appelt K,Dijk J,White SW,Wilson KS

更新日期：1984-08-02 00:00:00

abstract：:The upper temperature at which a living system can exist is limited by the hydrolytic breakdown rate of its chemical constituents. The peptide bonds of proteins, the phosphodiester and N-glycosyl bonds in RNA and DNA, and the pyrophosphate and N-glycosyl bonds in nucleotides such as ATP and NAD are among the more impo...

journal_title：Nature

authors： White RH

更新日期：1984-08-02 00:00:00

abstract：:Type III collagen is often found in the same tissues as type I collagen, yet the function and nature of the fibrils formed by the two collagens differ markedly. To understand the evolutionary history of the collagen gene family in more detail, we isolated the gene for type III collagen and compared its structure with ...

journal_title：Nature

authors： Yamada Y,Liau G,Mudryj M,Obici S,de Crombrugghe B

更新日期：1984-07-26 00:00:00

abstract：:The collagens represent an interesting example of a structurally related but genetically distinct family of proteins. Type I, the most abundant of the vertebrate collagens, comprises two pro alpha 1(I) chains and one pro alpha 2(I) chain, each containing terminal propeptides and a central domain of 338 (Gly, X, Y) rep...

journal_title：Nature

authors： Chu ML,de Wet W,Bernard M,Ding JF,Morabito M,Myers J,Williams C,Ramirez F

更新日期：1984-07-26 00:00:00

abstract：:Regulatory aspects of the Warnock Committee's report on reproductive technologies are summarized. A licensing authority with "substantial lay representation" would license practitioners and approve experimentation. Artificial insemination by donor would become a regulated service, and resulting children would be leg...

journal_title：Nature

authors：

更新日期：1984-07-26 00:00:00

abstract：:The commitment of non-dividing cells (in G0) to enter division can be studied using primary cultures of lymphocytes. The cells are stable in G0 unless stimulated by mitogen such as concanavalin A (Con A). Commitment to enter the division cycle depends on the expression of gene(s) induced by Con A and the synthesis of ...

journal_title：Nature

authors： Milner J

更新日期：1984-07-12 00:00:00

abstract：:A chimaeric gene, consisting of the 5'-flanking region of a member of the Pisum sativum gene family encoding ribulose 1,5-bisphosphate carboxylase linked to the coding region of a bacterial chloramphenicol acetyltransferase gene, has been introduced into the genome of the plant Nicotiana tabacum using a Ti plasmid of ...

journal_title：Nature

authors： Herrera-Estrella L,Van den Broeck G,Maenhaut R,Van Montagu M,Schell J,Timko M,Cashmore A

更新日期：1984-07-12 00:00:00

abstract：:Concern about the levels of lead in blood is widespread. There is uncertainty, however, about the relative importance of the various environmental sources. Lead in petrol is widely assumed to be one of the most important sources and air and dust have been identified as the main routes to man. Water is regarded as an i...

journal_title：Nature

authors： Elwood PC,Gallacher JE,Phillips KM,Davies BE,Toothill C

更新日期：1984-07-12 00:00:00

abstract：:Atrial extracts contain factors which induce potent natriuresis changes in renal haemodynamics, and relax pre-contracted vascular smooth muscle. Low-molecular-weight peptides which mimic these actions have now been purified by several groups, including ours (see accompanying paper), and higher-molecular-weight protein...

journal_title：Nature

authors： Yamanaka M,Greenberg B,Johnson L,Seilhamer J,Brewer M,Friedemann T,Miller J,Atlas S,Laragh J,Lewicki J

更新日期：1984-06-21 00:00:00

abstract：:Although it is well established that family members resemble each other in intelligence , the extent to which this results from either shared genes or a shared environment remains controversial, perhaps especially since the relevant evidence presented by Burt has been shown probably to have been fabricated. The influe...

journal_title：Nature

authors： Teasdale TW,Owen DR

更新日期：1984-06-14 00:00:00

abstract：:The thymus is the major, if not the sole site of maturation of T lymphocytes from their haematopoietic precursors. During embryonic life (at a few well-defined intervals, at least in birds) the thymus receives thymus-homing haematopoietic precursors that give rise to antigen-specific functional T lymphocytes. Although...

journal_title：Nature

authors： Ezine S,Weissman IL,Rouse RV

更新日期：1984-06-14 00:00:00

abstract：:The National Institutes of Health's Recombinant DNA Advisory Committee (RAC) has approved a commercial proposal by Advanced Genetic Sciences Inc. to field-test recombinant ice-nucleating bacteria. Its decision came two weeks after a federal judge halted a similar trial by researchers from the University of California...

journal_title：Nature

authors： Budiansky S

更新日期：1984-06-07 00:00:00

abstract：:Several hormones and neurotransmitters raise the cytosolic free Ca2+ concentration by stimulating the influx of Ca2+ and/or by mobilizing stored Ca2+. However, the link between the agonist receptor on the cell surface and the organelle(s) from which Ca2+ is mobilized is unknown. One feature of the agonists that increa...

journal_title：Nature

authors： Prentki M,Biden TJ,Janjic D,Irvine RF,Berridge MJ,Wollheim CB

更新日期：1984-06-07 00:00:00

abstract：:The injection of Rous sarcoma virus (RSV) into the wing web of newly hatched chicks causes a rapidly growing sarcomatous tumour which is palpable within 1 week of inoculation; and cultures of fibroblasts derived from chick embryos (CEF) and infected with RSV become rapidly transformed. Genetic studies have determined ...

journal_title：Nature

authors： Dolberg DS,Bissell MJ

更新日期：1984-06-07 00:00:00

abstract：:Modification of tyrosine residues of proteins has attracted great interest. Although phosphorylation has received most attention, tyrosine-O-sulphation is also common and has been closely investigated in the hormones gastrin and cholecystokinin (CCK). CCK regulates pancreatic enzyme secretion. It is always sulphated a...

journal_title：Nature

authors： Brand SJ,Andersen BN,Rehfeld JF

更新日期：1984-05-31 00:00:00

abstract：:The DNA sequences of the alcohol dehydrogenase (Adh) genes of four very closely related species of Drosophila show that the rates of nucleotide change vary greatly in different functional domains of this gene. A phylogeny of these species based on the Adh sequence data is consistent with that based on polytene chromos...

journal_title：Nature

authors： Bodmer M,Ashburner M

更新日期：1984-05-31 00:00:00

abstract：:Cell-cell interactions are thought to play a crucial part in determining the developmental fate of vertebrate cells and regulating their subsequent differentiation. In the peripheral nervous system, for example, signals from neuronal axons determine whether or not some Schwann cells wrap their plasma membrane concentr...

journal_title：Nature

authors： Mudge AW

更新日期：1984-05-24 00:00:00

abstract：:The heavy (H) and light (L) chains of antibodies consist of variable (V) and constant (C) regions. The V regions of the heavy and light chains form the antibody combining site. To determine whether a V region could be functional when joined to a polypeptide other than its own C region, we constructed a chimaeric gene ...

journal_title：Nature

authors： Sharon J,Gefter ML,Manser T,Morrison SL,Oi VT,Ptashne M

更新日期：1984-05-24 00:00:00

abstract：:Human T-cell leukaemias and lymphomas associated with the human T-cell leukaemia viruses (HTLV) are invariably neoplasms of cells with mature T-lymphocyte phenotype. Epstein-Barr virus-transformed B- lymphoycte lines which are productively infected with HTLV may be isolated from patients with HTLV malignancies, but no...

journal_title：Nature

authors： Chen IS,McLaughlin J,Golde DW

更新日期：1984-05-17 00:00:00

abstract：:H-2 class I antigens appear to direct the recognition of virus-infected and neoplastic transformed cells by cytotoxic T lymphocytes (CTLs). Here, to identify the regions of class I antigens involved in CTL recognition, four hybrid class I genes were constructed in which exons were exchanged between the H-2Kb and H-2Db...

journal_title：Nature

authors： Allen H,Wraith D,Pala P,Askonas B,Flavell RA

更新日期：1984-05-17 00:00:00

abstract：:The mechanism whereby eukaryotic pre-messenger RNAs are polyadenylated is unknown. Most models for polyadenylation invoke cleavage of precursor transcripts at the site of poly(A) addition followed by polymerization of A residues by poly(A) polymerase. Analysis of the sequences surrounding poly(A) addition sites has id...

journal_title：Nature

authors： Berget SM

更新日期：1984-05-10 00:00:00

abstract：:Eukaryotic cells contain genes termed proto-oncogenes (c-onc) which have the potential to transform cells in culture and induce tumours in vivo. Most of these genes have been identified by their occasional incorporation into retroviral genomes which can act as natural transducing vectors for these and perhaps other ce...

journal_title：Nature

authors： Sutrave P,Bonner TI,Rapp UR,Jansen HW,Patschinsky T,Bister K

更新日期：1984-05-03 00:00:00

abstract：:Evidence of myc gene transduction by feline leukaemia virus in several spontaneous lymphoid tumours of cats suggests that recombinant viruses carrying oncogenes may be much more involved in oncogenesis in natural conditions than previously recognized. ...

journal_title：Nature

authors： Neil JC,Hughes D,McFarlane R,Wilkie NM,Onions DE,Lees G,Jarrett O

更新日期：1984-04-26 00:00:00

abstract：:The human T-cell leukaemia and differentiation antigen HTA 1 is defined by the monoclonal antibody NA1/34 (ref. 1) and also recognized by the monoclonal antibody OKT6. Like class I products of the human major histocompatibility complex, it has a glycosylated heavy (alpha) chain of approximately 45-50,000 molecular wei...

journal_title：Nature

authors： Kefford RF,Calabi F,Fearnley IM,Burrone OR,Milstein C

更新日期：1984-04-12 00:00:00

abstract：:Attempts to inhibit the recognition of soluble antigens by T lymphocytes using antibodies specific for the antigen in question have been uniformally unsuccessful, in contrast to the observed specific inhibition of antibody generation by B cells. One exception is the unique situation whereby anti-hapten antisera inhibi...

journal_title：Nature

authors： Corradin G,Engers HD

更新日期：1984-04-05 00:00:00

abstract：:Reciprocal altruism refers to the exchange of beneficial acts between individuals, in which the benefits to the recipient exceed the cost to the altruist. Theory predicts that cooperation among unrelated animals can occur whenever individuals encounter each other regularly and are capable of adjusting their cooperativ...

journal_title：Nature

authors： Seyfarth RM,Cheney DL

更新日期：1984-04-05 00:00:00

abstract：:Sodium channels and receptors to serotonin and kainate were 'transplanted' from human brain into frog oocytes, by isolating messenger RNA from a fetal brain, and injecting it into Xenopus laevis oocytes. The mRNA was translated by the oocyte and induced the appearance of functional receptors and channels in its membra...

journal_title：Nature

authors： Gundersen CB,Miledi R,Parker I

更新日期：1984-03-29 00:00:00

abstract：:T-cell clones that grow continuously in tissue culture have become a major tool for studying the properties of T lymphocytes. It is therefore important to know to what extent such clones resemble their normal counterparts. Several reports have appeared recently which demonstrate that long-term T-cell lines may lose th...

journal_title：Nature

authors： Simon MM,Weltzien HU,Bühring HJ,Eichmann K

更新日期：1984-03-22 00:00:00

abstract：:The neurohypophysial hormone vasopressin exerts antidiuretic, vasopressor and behavioural effects (for example, facilitation of memory processes). Vasopressin may alter animal behaviour via direct effect on brain processes. Recently, however, it has been suggested that vasopressin acts mainly at peripheral receptor sy...

journal_title：Nature

authors： de Wied D,Gaffori O,van Ree JM,de Jong W

更新日期：1984-03-15 00:00:00

abstract：:The methylation of vertebrate DNA at the 5-position of approximately 3-10% of its cytosine residues occurs in a sequence-specific and tissue-specific manner and has been implicated in the control of transcription. How these differences are established and how they mediate the initiation or maintenance of transcription...

journal_title：Nature

authors： Huang LH,Wang R,Gama-Sosa MA,Shenoy S,Ehrlich M

更新日期：1984-03-15 00:00:00

abstract：:It has long been thought that mature oligodendrocytes in the adult mammalian central nervous system (CNS) are post-mitotic and are unable to proliferate in response to injury. The implications of this have been profound, because it has been suggested that this failure of oligodendrocytes to undergo mitosis is perhaps ...

journal_title：Nature

authors： Ludwin SK

更新日期：1984-03-15 00:00:00

abstract：:'Identifier' or ID sequences are present in 62% of the RNA polymerase II and III transcripts made in vitro from brain nuclei but in fewer than 4% of the transcripts made from the nuclei of other tissues. An homologous 160-nucleotide cytoplasmic poly(A)+ RNA species, BC1, and a smaller species, BC2, are located in vivo...

journal_title：Nature

authors： Sutcliffe JG,Milner RJ,Gottesfeld JM,Lerner RA

更新日期：1984-03-15 00:00:00

abstract：:Three Hipparion trails, two from adults and one from a juvenile dating from about 3.5 Myr ago, have now been found in Laetoli. Comparison of the Hipparion footprints with a variety of imprints made by domestic horses showed that the animals moved with a running walk over the soft and slippery soil of Laetoli: in the a...

journal_title：Nature

authors： Renders E

更新日期：1984-03-08 00:00:00

abstract：:Recently, several groups have initiated studies on cytosolic proteins that bind to isolated secretory vesicle membranes in the presence of Ca2+ in order to identify proteins that may regulate exocytosis. Two major chromaffin granule binding proteins, of molecular weights 32,000 (32K) and 34,000 (34K), were reported to...

journal_title：Nature

authors： Creutz CE,Harrison JR

更新日期：1984-03-08 00:00:00