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CONfORMATION AND STRUCTURE Of 9-ALPHA-D-ARABINOfURANOSYLADENINE

BIOCHIMICA ET BIOPHYSICA ACTA 1980年第1期610卷 20-27页

作者： CLINE, SJ HODGSON, DJ UNIV N CAROLINA DEPT CHEM CHAPEL HILL NC 27514 USA

The crystal structure of the nucleoside 9-.alpha.-D-arabinofuranosyladenine (C10H13N5O4) was determined by 3-dimensional X-ray counter data. The adenosine analog crystallizes in space group P212121 of the orthorhombic system with 8 formula units in a cell of dimensions a, 6.720(5), b, 40.188(35), c, 8.357(8) .ANG.. Hence, there are 2 crystallographically independent molecules in the unit cell. The structure was solved by direct methods and refined by full-matrix least-squares techniques to a final value of the conventional R-factor of 0.076 using 1173 independent intensity data. In the crystal, both independent molecules (A and B) adopt the anti conformation (for an .alpha.-sugar), with glycosyl torsion angles, .chi., of -***. and -***.;these are comparable to values found in other .alpha.-nucleosides. The conformation about the extracyclic C(4'')-C(5'') bond is guache-guache in both molecules. The sugar pucker is C(2'')-exo-C(3'')-endo, 2T3, in molecule A and C(3'')-endo, 3E, in molecule B. Conformational analysis of rotation about the N(9)-C(1'') glycosyl bond was performed by use of CNDO[complete neglect of differential overlap]/2 molecular orbital calculations. The observed conformation may not be the global minimum, but it apparently lies only 0.4 kcal .cntdot. mol-1 higher in energy than the global minimum. The highest energy barrier to rotation around the glycosyl bond is calculated to be only 1.1 kcal .cntdot. mol-1, which is comparable to the value calculated for adenosine.

关键词： Arabinofuranosyladenine structure Conformation X-ray crystallography Molecular orbital calculation α -Ara f Ade 9-α-D-arabinofuranosyladenine β -Ara f Ade 9-β-D-arabinofuranosyladenine

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PROSTAGLANDIN STIMULATION Of CANINE PLATELET ADENYLATE-CYCLASE

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THROMBOSIS RESEARCH 1980年第1-2期19卷 119-124页

作者： LONGENECKER, GL KOPACIEWICZ, LJ PALMER, SJ PALMER, GC Department of Pharmacology University of South Alabama College of Medicine Mobile Alabama 36688 USA

Homogenates of washed canine platelets possessed an adenylate cyclase system that was potently activated by prostaglandin (PG) E1 and to a lesser extent by PGE2, PGA2 and ***.. The effect of the PG species on adenylate cyclase were not augmented by the GTP analog, 5''-guanylyl imidodiphosphate. The drug 1-epinephrine, a stimulator of canine platelet aggregation induced by other agents, acted as a weak inhibitor of the adenylate cyclase.

关键词： Adenylate Cyclase Prostaglandins (E 1 E 2 f 2a A 2 ) Canine Platelets Cyclic Adenosine-3′ 5′-monophosphate

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ESTROGEN-RECEPTOR IN BREAST-CANCER - A SCATCHARD ANALYSIS Of PLASMA-PROTEIN INTERfERENCE

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JOURNAL Of STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY 1980年第11期13卷 1265-1268页

作者： GOLDENBERG, K CARROLL, RE UNION UNIV ALBANY MED COLL DEPT PREVENT & COMMUNITY MED ALBANY NY 12208 USA

Endocrine additive or ablative therapies are often beneficial in patients with advanced breast cancer containing significant estrogen receptor. frequently observed conditions of plasma protein interference with receptor assay (4) are solved by Scatchard analysis. Each condition is resolved using 2 popular, approximating techniques to demonstrate when either or both are appropriate. A robust nomograph is constructed for this and similar hormonal systems. The effect of errors in assigning responsiveness and treatment modalities are discussed.

关键词： E - R estrogen receptor B bound estrogen concentration f free estrogen concentration (unbound) Co constant B / f value where the X asymptote is extrapolated back to the Y axis SHBG sex hormone binding globulin Pg-R progesterone receptors

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THE ULTRASTRUCTURE Of CENTRIOLE IN MAMMALIAN TISSUE-CULTURE CELLS

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CELL BIOLOGY INTERNATIONAL REPORTS 1980年第11期4卷 1037-1044页

作者： VOROBJEV, IA CHENTSOV, YS A.N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry Moscow State University Moscow USSR

Structural polarity of centriole has been shown by analyzing serial sections of centrioles in the tissue culture cells of mouse, man, pig and Chinese hamster. Its major component is nine microtubule triplets. The inclination of the triplets towards the radius at the proximal end of the centriole is smaller than at the distal one. The internal tubule of the triplet has a smaller diameter than the middle and external ones; The triplets are bound by links of various nature all over their length. In the middle part, in the centriole lumen there is an amorphous hub; in the distal part, a thin fibre that is helically wound. In the proximal part, there are bases along the triplets, and handles stretch from the internal tubules. In the middle and distal parts, there are accumulations of an electron dense substance along the middle tubules. At the distal end, the centriole lumen is filled with an amorphous substance, whereas the proximal end is free from it. from outside, appendages are attached to the triplets at the distal end. The centriole structure is identical in all the cell types studied, except for those of Chinese hamster.

关键词： A B C inner middle outer triplet microtubules ap appendages tb triplet bases con connectives (A-C links) h hub f fibre rl ring of links in the middle part

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ULTRACRYOTOMY - DEVELOPMENT AND APPLICATION - WITH EXAMPLES fROM THE YEAST CYTOLOGY

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ACTA HISTOCHEMICA 1980年第1期66卷 59-84页

作者： BOHM, KJ Akademie der Wissenschaften der DDR Forschungszentrum für Molekularbiologie und Medizin Zentralinstitut für Mikrobiologie und Experimentelle Therapie Jena (Direktor: Prof. Dr. U. Taubeneck)

The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning and post-staining the sections for transmission electron microscopy) are submitted to critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. fundamental considerations of chemical prefixation and post-staining are supported by examples from yeast cytology. furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.

关键词： CHR Chromatin CW Zellwand E Einbettungsmedium ER endoplasmatisches Reticulum f filamentbündel K Proteinkristalle KT Kristall-assoziierte Tubuli M Mitochondrien MT Mikrotubuli der Mitosespindel N Kern NAO Kern-assoziiertes Organell NE Kernhülle NP Kernporen P Plasmamembran R Ribosomen T Tubuli V Vakuole

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A COMPARISON Of THE Sf0 TO 1000 PLASMA-LIPOPROTEINS fROM RABBITS fED CHOLESTEROL AND HUMANS WITH TYPE-III HYPERLIPOPROTEINEMIA

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INTERNATIONAL JOURNAL Of BIOCHEMISTRY 1980年第3期12卷 473-477页

作者： BOSANQUET, AG MUNSTER, D BICKERSTAffE, R fRASER, R CHRISTCHURCH CLIN SCH MED DEPT PATHOL CHRISTCHURCH NEW ZEALAND UNIV CANTERBURY LINCOLN COLL DEPT BIOCHEM CHRISTCHURCH NEW ZEALAND CHRISTCHURCH HOSP DEPT BIOCHEM CHRISTCHURCH NEW ZEALAND

Total low density lipoprotein (TLDL) spectra of plasma samples from humans with type III hyperlipoproteinemia and plasma from rabbits which had been fed a diet containing added cholesterol for 0-43 days were determined by analytical ultracentrifugation. The comparison showed very similar TLDL spectra between the 2 groups when the spectra were taken individually or averaged. Variations in the response of rabbits to dietary cholesterol are reported and discussed.

关键词： TLDL total low density lipoproteins, S f > 0 LDL low density lipoproteins, S f 0–12 IDL intermediate density lipoproteins, S f 12–20 VLDL very low density lipoproteins S f 20–400 SCR small chylomicron remnants LCR large chylomicron remnants

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AMINO-ACID-INCORPORATION BY ISOLATED RAT-LIVER MITOCHONDRIA INTO 2 PROTEIN-COMPONENTS Of MITOCHONDRIAL ATPASE COMPLEX - LACK Of INCORPORATION INTO DICYCLOHEXYLCARBODIIMIDE BINDING PROTEOLIPID

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fEBS LETTERS 1980年第2期114卷 197-201页

作者： KUZELA, S LUCIAKOVA, K LAKOTA, J Cancer Research Institute Slovak Academy of Sciences ul. Čs. armády 21 880 32 Bratislava Czechoslovakia

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PRACTICAL AND THEORETICAL ASPECTS IN THE ANALYSIS Of STEROID-RECEPTORS

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JOURNAL Of STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY 1980年第10期13卷 1133-1145页

作者： BRAUNSBERG, H HAMMOND, KD ST MARYS HOSP SCH MED DEPT CHEM PATHOL LONDON W2 1PG ENGLAND

The limitations of analytical methods and calculations used widely in the estimation of steroid receptor site concentrations and Kd are discussed. Errors arising from loss of steroid during equilibration or analysis or both, the use of excess radioinert steroid to estimate non-specific binding, inadequate correction for non-specific binding and other miscalculations, loss of receptor during analysis, dilution of radioactive with endogenous steroid and statistical counting errors are considered and assessed by theoretical models and of analytical data for progesterone receptors in human endometrium. four linear plot methods are compared for estimating receptor parameters from experimental data. Single point assay results when compared with estimates of progesterone receptor site concentration by Scatchard analysis do not always give reliable results. Recommendation for further investigations are put forward with a view to improving the quantitative reliability of receptor site determinations.

关键词： T total steroid concentration B T concentration of total bound steroid B ns concentration of “non-specifically” bound steroid B s concentration of steroid bound to specific receptorsites f concentration of unbound steroid f ns concentration of unbound steroid in equilibrium with “non-specific” binding components only in the absence of receptor binding f T concentration of unbound steroid in equilibrium with both receptor and “non-specific binding” components P NS and P s are concentrations of “non-specific” and receptor binding sites respectively K NS and K S are dissociation constants of “non-specific” and receptor binding sites respectively DCC dextran-coated charcoal PEG polyethylene glycol r correlation coefficient N number of ligand concentrations used in receptor assay

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PROPERTIES Of SATELLITE DNAS Of HIGHER-PLANTS

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PLANT SCIENCE LETTERS 1980年第4期19卷 325-338页

作者： BERIDZE, T Institute of Plant Biochemistry Academy of Sciences of the Georgian SSR Tbilisi 380031 U.S.S.R.

Satellite DNA of 3 spp. of higher plants, runner bean (Phaseolus coccinesu), black mustard (Brassica nigra) and lemon (Citrus limon) were isolated by preparative ultracentrifugation in CsCl density gradients. Differential melting curves of satellite DNA show gross heterogeneity. Satellite DNA of analyzed plants contain fast and slow renaturing fractions. The amount and kinetic complexities of these fractions varied between the satellites. Calculations carried out on the basis of the values of Tm and buoyant density in CsCl gradients demonstrated that lemon and bean satellite DNA were enriched in 5-methylcytosine. In the lemon satellite DNA it amounted to 24.1%. By the distribution of plant satellite DNA in actinomycin D-CsCl and Hg2+-CsSO4 density gradients several components were observed.

关键词： DMC differential melting curve m 5 C 5-methylcytosine r f molar ratio of Hg 2+ to DNA phosphate SSC 0.15 M NaCl, 0.015 M sodium citrate transition temperature temperature, corresponding to maximum of the peak on DMC

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A CONSTRUCTION fOR GENERALIZED HADAMARD-MATRICES

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JOURNAL Of STATISTICAL PLANNING AND INfERENCE 1980年第4期4卷 365-368页

作者： SEBERRY, J University of Sydney Sydney Australia

We prove that if p r and p r − 1 are both prime powers then there is a generalized Hadamard matrix of order p r ( p r − 1) with elements from the elementary abelian group Z p x⋯x Z p . This result was motivated by results of Rajkundia on BIBD's. This result is then used to produce p r − 1 mutually orthogonal f -squares f ( p r ( p r − 1); p r − 1).

关键词： Primary 62K10, 62K15 Secondary 05B15 f -squares

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