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Lutalyse*, a commercial preparation of prostaglandin F2a was injected intramuscularly into nulliparous heifers of the German Brown, Holstein—Friesian and White Fulani cattle. Two injections, 25mg/animal each time, were given at intervals of 12 days. All the heifers were inseminated 80h after the second injection. Heifers that were cycling responded well to the treatment and had a higher conception rate than the controls.  相似文献   

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Superoxide dismutase (SOD, EC 1.15.1.1) plays an important antioxidant defense role in organisms exposed to oxygen. Copper- and zinc-containing SOD (Cu/Zn-SOD) catalysis and the change in folding behavior of this enzyme in response to inactivators are therefore of interest. We studied the inhibitory effects of trifluoroethanol (TFE) on the activity and conformation of a Cu/Zn-SOD from Bos taurus. We found that TFE inactivated the enzyme and disrupted the tertiary and secondary structures of Cu/Zn-SOD. Kinetic studies showed that TFE-induced inactivation of Cu/Zn-SOD follows first-order reaction kinetics and that TFE binding sites are distinct from the copper- and zinc-containing active site. These structural changes occurred prior to enzyme activity loss. A computational docking simulation of Cu/Zn-SOD and TFE (binding energy of Dock 6.3: -11.52 kcal/mol) suggested that THR37, ASP40, and GLU119, which are located near the active site, interact with TFE. Evaluation of the ligand binding kinetics of Cu/Zn-SOD during unfolding in the presence of TFE combined with computational prediction allowed us to gain insight into the inactivation of Cu/Zn-SOD.  相似文献   

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The objective of the present study was to develop and validate highly sensitive and economic enzymeimmunoassay (EIA) for prolactin determination in mithun blood plasma on microtitreplates using the biotin-streptavidin amplification system and second antibody coating technique and to apply this procedure during milk let down and cyclicity in mithuns (Bos frontalis), a semi-wild ruminant. Biotin was coupled to prolactin and used to bridge between streptavidin peroxidase and immobilized antiserum in competitive assay. The EIA was carried out directly in 50 microl mithun plasma. The sensitivity of the EIA procedure was 0.1 ng/ml plasma. Plasma volumes viz., 12.5, 25 and 50 microl did not influence much the shape of standard curve though a slight drop in the OD450 was seen with higher plasma volumes. A parallelism test was carried out to compare the endogenous mithun plasma prolactin with bovine prolactin standards used in the assay. It showed good parallelism with the bovine standard curve. Plasma prolactin was estimated in six cyclic mithun cows during an estrous cycle. Mean plasma prolactin concentrations around the day of estrus were recorded to be higher than any other day of the cycle. Prolactin profiles were also obtained in three mithuns before, during and after milking. A sharp release of prolactin shortly after udder stimulation was observed. High levels of prolactin were maintained during milking, falling sharply thereafter. In conclusion, the EIA developed for prolactin determination in mithun blood plasma is sufficiently reliable, economic and sensitive enough to estimate prolactin in all physiological variation in mithun.  相似文献   

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Dickeya dadantii is a broad host range phytopathogenic bacterium provoking soft rot disease on many plants including Arabidopsis. We showed that, after D. dadantii infection, the expression of the Arabidopsis BOS1 gene was specifically induced by the production of the bacterial PelB/C pectinases able to degrade pectin. This prompted us to analyze the interaction between the bos1 mutant and D. dadantii. The phenotype of the infected bos1 mutant is complex. Indeed, maceration symptoms occurred more rapidly in the bos1 mutant than in the wild type parent but at a later stage of infection, a necrosis developed around the inoculation site that provoked a halt in the progression of the maceration. This necrosis became systemic and spread throughout the whole plant, a phenotype reminiscent of that observed in some lesion mimic mutants. In accordance with the progression of maceration symptoms, bacterial population began to grow more rapidly in the bos1 mutant than in the wild type plant but, when necrosis appeared in the bos1 mutant, a reduction in bacterial population was observed. From the plant side, this complex interaction between D. dadantii and its host includes an early plant defence response that comprises reactive oxygen species (ROS) production accompanied by the reinforcement of the plant cell wall by protein cross-linking. At later timepoints, another plant defence is raised by the death of the plant cells surrounding the inoculation site. This plant cell death appears to constitute an efficient defence mechanism induced by D. dadantii during Arabidopsis infection.  相似文献   

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A unique multibranched cyclomaltooligosaccharide (cyclodextrin, CD) of 6(1),6(3),6(5)-tri-O-alpha-maltosyl-cyclomaltoheptaose [6(1),6(3),6(5)-tri-O-alpha-maltosyl-beta-cyclodextrin, (G(2))(3)-betaCD] was prepared. The physicochemical and biological properties of (G(2))(3)-betaCD were determined together with those of monobranched CDs (6-O-alpha-D-glucopyranosyl-alpha-cyclodextrin (G(1)-alphaCD), 6-O-alpha-D-glucopyranosyl-beta-cyclodextrin (G(1)-betaCD), and 6-O-alpha-maltosyl-beta-cyclodextrin (G(2)-betaCD)). NMR spectra of (G(2))(3)-betaCD were measured using various 2D NMR techniques. The solubility of (G(2))(3)-betaCD in water and MeOH-water solutions was extremely high in comparison with nonbranched betaCD and was about the same as that of the other monobranched betaCDs. The formation of an inclusion complex of (G(2))(3)-betaCD with stereoisomers (estradiol, retinoic acid, quinine, citral, and glycyrrhetinic acid) depends on the cis-trans isomers of guest compounds. The cis isomers of estradiol, retinoic acid, and glycyrrhetinic acid were included more than their trans isomers, while the trans isomers of citral and quinine fit more tightly than their cis isomers. (G(2))(3)-betaCD was the most effective host compound in the cis-trans resolution of glycyrrhetinic acid. Among the branched betaCDs, (G(2))(3)-betaCD exhibited the weakest hemolytic activity in human erythrocytes and showed negligible cytotoxicity in Caco-2 cells up to 200 microM. These results indicate unique characteristics of (G(2))(3)-betaCD in some biological responses of cultured cells.  相似文献   

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Methanobactin (mb) is a novel chromopeptide that appears to function as the extracellular component of a copper acquisition system in methanotrophic bacteria. To examine this potential physiological role, and to distinguish it from iron binding siderophores, the spectral (UV–visible absorption, circular dichroism, fluorescence, and X-ray photoelectron) and thermodynamic properties of metal binding by mb were examined. In the absence of Cu(II) or Cu(I), mb will bind Ag(I), Au(III), Co(II), Cd(II), Fe(III), Hg(II), Mn(II), Ni(II), Pb(II), U(VI), or Zn(II), but not Ba(II), Ca(II), La(II), Mg(II), and Sr(II). The results suggest metals such as Ag(I), Au(III), Hg(II), Pb(II) and possibly U(VI) are bound by a mechanism similar to Cu, whereas the coordination of Co(II), Cd(II), Fe(III), Mn(II), Ni(II) and Zn(II) by mb differs from Cu(II). Consistent with its role as a copper-binding compound or chalkophore, the binding constants of all the metals examined were less than those observed with Cu(II) and copper displaced other metals except Ag(I) and Au(III) bound to mb. However, the binding of different metals by mb suggests that methanotrophic activity also may play a role in either the solubilization or immobilization of many metals in situ.  相似文献   

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Ito H  Tanaka S  Miyasaka M 《Biopolymers》2002,65(2):61-80
We utilize electrophoresis and find that a thermally treated equimolar mixture of the oligonucleotide d(G(5)T(5)) and its complementary oligonucleotide d(A(5)C(5)) exhibits either two bands or a single band in one lane, depending on the conditions of the incubation solutions. The thermally treated d(G(5)T(5)) solution loaded in a different lane exhibits a single band of the parallel quadruplex [d(G(5)T(5))](4), which is composed of homocyclic hydrogen-bonded G(4) and T(4) tetrads previously proposed. For the thermally treated equimolar mixture of d(G(5)T(5)) and d(A(5)C(5)), the fast band is assigned to a Watson-Crick d(G(5)T(5)). d(A(5)C(5)) duplex, so that the slow band with the same low mobility as that of [d(G(5)T(5))](4) may be assigned to either [d(G(5)T(5))](4) itself or a [d(G(5)T(5)). d(A(5)C(5))](2) quadruplex. If the latter compound is true, this may be the antiparallel quadruplex composed of the heterocyclic hydrogen-bonded G-C-G-C and T-A-T-A tetrads proposed previously. After removing these three bands for the duplex and two kinds of hypothetical quadruplexes, we electrophoretically elute the corresponding compounds in the same electrophoresis buffer using an electroeluter. The eluted compounds are ascertained to be stable by electrophoresis. The circular dichroism (CD) and UV absorption spectra measured for the three isolated compounds are found to be clearly different. For the electrophoretic elution of the hypothetical [d(G(5)T(5))](4) quadruplex, the result of the molecularity of n = 4 obtained from the CD melting curve analysis provides further support for the formation of the parallel [d(G(5)T(5))](4) quadruplex already proposed. For the thermally treated equimolar mixture of d(G(5)T(5)) and d(C(5)A(5)), the fast band with a molecularity of n = 2 corresponds to the Watson-Crick duplex, d(G(5)T(5)). d(A(5)C(5)). The slow band with a molecularity of n = 4 indicates the antiparallel quadruplex [d(G(5)T(5)). d(A(5)C(5))](2), whose observed CD and UV spectra are different from those of [d(G(5)T(5))](4). By electrophoresis, after reannealing the eluted compound [d(G(5)T(5)). d(A(5)C(5))](2), a distinct photograph showing the band splitting of this quadruplex band into the lower duplex and upper quadruplex bands is not possible; but by a transilluminator, we occasionally observe this band splitting with the naked eye. The linear response polarizability tensor calculations for the thus determined structures of the [d(G(5)T(5))](4) quadruplex, the McGavin-like [d(G(5)T(5)). d(A(5)C(5))](2) quadruplex, and the Watson-Crick d(G(5)T(5)). d(A(5)C(5)) duplex are found to qualitatively predict the observed CD and UV spectra.  相似文献   

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Xia Z  Zhuang J 《Luminescence》2012,27(5):379-381
A novel blue‐emitting Sr3.5Y6.5O2(PO4)1.5(SiO4)4.5:Eu2+ phosphor was synthesized via a solid‐state reaction. Powder X‐ray diffraction (XRD) analysis demonstrated that the Sr3.5Y6.5O2(PO4)1.5(SiO4)4.5 host had a hexagonal crystal structure in the space group P63/m and unit cell parameters a = 9.418 Å, c = 6.900 Å. The as‐prepared phosphor showed a blue emission and all the main emission peaks were located at around 466 nm for different excitation wavelengths of 297, 333 and 391 nm. The temperature dependence of the photoluminescence property was investigated in the range 20–250 °C, and the emission intensity decreased to 71% of the initial value at room temperature on increasing the temperature to 150 °C. According to the classical theory of fluorescent thermal quenching, the activation energy (ΔE) for the thermal quenching luminescence of the as‐prepared Sr3.45Y6.5O2(PO4)1.5(SiO4)4.5:0.05Eu2+ phosphor was determined to be 0.20 eV. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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Summary The serum groups Gm(1) [Gm(a)], Gm(2) [Gm(x)], Gm(4) [Gm(f)]. Gm(12) [Gm(b)] and Inv(1) [Inv(1)] of 2000 sera of healthy blood donors from the land Hesse were examined. The results obtained were compared with those known until now. Three persons, not related to each other, possessed the extremely rare phenotype Gm(-1, 2, 4, 12) [Gm (a-x+b+f+)]. In 0.75% of the cases we found a discordant behaviour of the factors Gm(4) and Gm(12) [Gm(f) and Gm(b)].
Zusammenfassung 2000 Seren von gesunden Blutspendern aus Hessen wurden bezüglich der Gamma-Globulin-Serumgruppen Gm(1) [Gm(a)], Gm(2) [Gm(x)], Gm(4) [Gm(f)]. Gm(12) [Gm(b)] und Inv(1) [Inv(1)] untersucht. Die gefundenen Resultate wurden mit den bisher bekannten verglichen. Drei miteinander nicht verwandte Personen wiesen den äußerst seltenen Phänotyp Gm(-1, 2, 4, 12) [Gm(a-x+b+f+)] auf. In 0.75% der Fälle fanden wir ein diskordantes Verhalten der Faktoren Gm(4) und Gm(12) [Gm(f) und Gm(b)].


Director: Prof. Dr. W. Wachsmuth

Director: Prof. Dr. W. Spielmann

The nomenclature suggested by WHO at a round-table conference over genes, genotypes and allotypes of immunglobulins is used. The conference took place in Geneva on the 1965 31. 5. to the 5. 6. [5].

With technical assistance of S. Mohs.  相似文献   

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