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171.
The Biopolymer Markup Language.   总被引:6,自引:0,他引:6  
SUMMARY: An XML derived from a data model designed to be a hierarchical representation of an organism has been specified and a browser to use this language has been developed. AVAILABILITY: The language definition is available in HTML form at http://www.proteometrics.com/BIOML/. The BioML browser is available on request from the author.  相似文献   
172.
173.
STACE, C. A. & JARVIS, C. E., 1985. TypiHcation of Linnaean taxa of annual Poaceae: Poeae related to Vulpia and Desmazeria. The status and typification of 15 Linnaean species of annual grasses related to Vulpia and Desmazeria are discussed. Of these 15, eight are represented by holotypes or lectotypes in LINN, two by lectotypes in Herb. A. van Royen (L), and one by a neotype in LINN. One (Festuca marina) is based on a pre-Linnaean polynomial and is represented by a lectotype in Herb. Sloane (BM); one (Cynosurus durus) has no known type specimens and we have chosen a Barrelier (1714) illustration as lectotype; one (Nardus aristatus) is an illegitimate name change for Nardus incurvus Gouan, for which we have selected a Scheuchzer (1719) illustration as lectotype; and finally Festuca incrassala appeared on a cancelled page of Species Plantarum and has no nomenclatural standing.  相似文献   
174.
W D Davies  J Pittard  B E Davidson 《Gene》1985,33(3):323-331
Defective transducing phages carrying aroG, the structural gene for phenylalanine (phe)-inhibitable phospho-2-keto-heptonate aldolase (EC 4.1.2.15; previously known as 3-deoxy-D-arabinoheptulosonate-7-phosphate synthetase[phe]), have been isolated, and DNA from two of these phages has been used to construct a restriction map of the region from att lambda to aroG. A 7.6-kb PstI-HindIII fragment from one of these phages was cloned into pBR322 and shown to contain aroG. The location of aroG within the 7.6 kb was established by subcloning and Tn3 transpositional mutagenesis. A fragment carrying the aroG promoter and operator has been cloned into a high copy number promoter-cloning vector (pMC489), and the resulting aroGpo-LacZ' (alpha) fusion subcloned in a low copy number vector. Strains with this fusion on the low copy number vector exhibit negative regulation of beta-galactosidase expression by both phenylalanine and tryptophan and positive regulation by tyrosine in a tyrR+ background.  相似文献   
175.
Experiments on frogs were performed to examine the effect of the M-cholinomimetic pilocarpine on the heart. It was discovered that at concentrations of 10(-15)--10(-5) g/ml pilocarpine exerted only an adverse chronotropic effect on the perfused heart. When applied at a concentration of 10(-4) g/ml the drug produced a negative as well as a positive chronotropic effect. The latter occurred spasmodically (without progressive rise in the heart rate) in association with a slow heart rate. In some experiments such effects were preceded by a certain deceleration of the heart. In experiments with positive chronotropic effects, arrhythmias and sinoatrial dissociation were observed sometimes. Experiments with recording of the electrograms of the sinuses and lower parts showed that such effects were caused not by pacemaker acceleration but by the removal of the blockade of conduction, between the pacemaker and the atria. As far as the pacemaker is concerned, pilocarpine exerted only a negative chronotropic effect.  相似文献   
176.
177.
Carbon monoxide dehydrogenase (CO dehydrogenase) from Rhodospirillum rubrum was shown to be an oxygen-sensitive, nickel, iron-sulfur, and zinc-containing protein that was induced by carbon monoxide (CO). The enzyme was purified 212-fold by heat treatment, ion-exchange, and hydroxylapatite chromatography and preparative gel electrophoresis. The purified protein, active as a monomer of Mr = 61,800, existed in two forms that were comprised of identical polypeptides and differed in metal content. Form 1 comprised 90% of the final activity, had a specific activity of 1,079 mumol CO oxidized per min-1 mg-1, and contained 7 iron, 6 sulfur, 0.6 nickel, and 0.4 zinc/monomer. Form 2 had a lower specific activity (694 mumol CO min-1 mg-1) and contained 9 iron, 8 sulfur, 1.4 nickel, and 0.8 zinc/monomer. Reduction of either form by CO or dithionite resulted in identical, rhombic ESR spectra with g-values of 2.042, 1.939, and 1.888. Form 2 exhibited a 2-fold higher integrated spin concentration, supporting the conclusion that it contained an additional reducible metal center(s). Cells grown in the presence of 63NiCl2 incorporated 63Ni into CO dehydrogenase. Although nickel was clearly present in the protein, it was not ESR-active under any conditions tested. R. rubrum CO dehydrogenase was antigenically distinct from the CO dehydrogenases from Methanosarcina barkeri and Clostridium thermoaceticum.  相似文献   
178.
Antibodies to calcitonin, parathyroid hormone and cortisol are detected in acute stage of infection-caused bronchial asthma. The appearance of antibodies is paralleled by marked hypercalcaemia. The antibodies may bind excessive hormones in the blood, preventing further hormonal imbalance. Ten-day treatment with glucocorticoids decreased the amount of antibodies possibly due to normalization of hormonal secretion and restoration of their balance. As a result, calcium blood levels returned to normal.  相似文献   
179.
Characterization of staphylococci   总被引:11,自引:0,他引:11  
A total of 158 Staphylococcus strains from various sources were characterized by biochemical, physiological, and morphological tests. Numerical taxonomy was applied by using these features. Taxonomic analysis was done with programs run under the MVS-TSO system of the IBM 370 complex and PDP-10 system of the National Institutes of Health. DNA-DNA hybridization with nitrocellulose filters was done to compare selected atypical cultures with American Type Culture Collection reference strains. We found that the use of the nomenclature of Bergey's Manual (8th edition) to identify these strains by species was not adequate. DNA homology values supported the formation of Staphylococcus hyicus subsp. hyicus separate from Staphylococcus aureus, Staphylococcus epidermidis, and Staphylococcus saprophyticus. The three tests that best separated these strains into four species were (i) tube coagulase (6-h or 24-h porcine plasma or 24-h Difco rabbit plasma), (ii) production of acetoin or acid aerobically from ribose, maltose, or trehalose, and (iii) growth in the presence of novobiocin. Four strains of S. hyicus subsp. hyicus (VII76, VII113, VII131, and VA519) gave typical enterotoxigenic responses in monkey-feeding tests but were negative for enterotoxins A through E, suggesting the presence of one or more new enterotoxins. Two coagulase-negative, heat-stable DNase-positive strains (D143 and ARM) could not be classified by either DNA-DNA hybridization or numerical taxonomy, and D143 was enterotoxigenic as measured by the monkey-feeding bioassay. DNA homology showed that strain FRI-698M was more closely related to S. epidermidis than to S. aureus, yet it produced enterotoxin D. These data suggest the occurrence of coagulase-negative enterotoxigenic strains that are not S. aureus; nonetheless, a positive tube coagulase test and heat-stable DNase test should together be useful for routine screening of most potentially enterotoxigenic staphylococci in foods.  相似文献   
180.
Chicken gizzard tropomyosin, like rabbit skeletal tropomyosin, inhibits and activates skeletal actomyosin subfragment 1 ATPase at low and high [subfragment 1], respectively, showing that both smooth and skeletal tropomyosin qualitatively produce similar cooperative effects on activity. For gizzard tropomyosin, however, the extent of the inhibition was less, and the activation curve rose more sharply at lower [subfragment 1]. In terms of a two-state cooperative activity model for the actin-tropomyosin filament (Hill, T. L., Eisenberg, E., and Chalovich, J. (1981) Biophys. J. 35, 99-112), these results qualitatively suggest that, for the gizzard tropomyosin system, more units are initially in the active state (in the absence of subfragment 1) and that the switching of units to the active state is more cooperative. The greater cooperativity indicated for the gizzard system may be a consequence of the greater rigidity of gizzard tropomyosin indicated from conformational studies.  相似文献   
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