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排序方式: 共有376条查询结果,搜索用时 31 毫秒
1.
2.
L V Antonova A A Kamenski? T I Vlasova N Iu Sarycheva V N Nezavibat'ko 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(11):569-571
Heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro (ACTH4-10 analog) at a dose of 0.015 mg/kg failed to alter open field behaviour of rats in the first test series. The peptide abolished amphetamine-induced stimulation of the exploratory and grooming behaviour. Extinction of the rats' exploratory behaviour during second test series in the open field (7 days later) was disturbed when haloperidol or apomorphine were injected before the first test series. When the peptide was administered with haloperidol or apomorphine, the extinction tended to become normal. Heptapeptide failed to change noradrenaline, dopamine or 5-hydroxytryptamine content in the rat forebrain. However, this peptide at a concentration of 10(-4) M moderately diminished tyrosine hydroxylation velocity in the rat striatal or hypothalamic synaptosomes, the effect depending on tyrosine concentration. These data suggest the involvement of catecholaminergic component into the heptapeptide action on the behaviour of rats. 相似文献
3.
M S Petrova R G Shakirova N A Antonova G N Feoktistova 《Antibiotiki i khimioterapii͡a》1992,37(11):40-43
The data accumulated within the last years required revision of the indications to the use of antibiotics in treatment of pertussis. One of the aims of antibiotic therapy in pertussis was to prevent colonization of B. pertussis in the respiratory tracts. With that end in view the choice of antibiotics should be limited by those, to which the pathogen is the most sensitive i.e. erythromycin, ampicillin and augmentin. Comparative efficacy of erythromycin and ampicillin during the first 2 weeks of the disease was studied in 79 infants at the age not older than 1 year with pertussis and it was shown that erythromycin was advantageous by its therapeutic activity and less side effects. Expedience of the antibiotic therapy during the spastic period for providing a preventive effect on development of bronchopulmonary complications was studied in 201 patients with pertussis. No preventive effect of the antibiotics on development of the bronchopulmonary complications defined by the secondary bacterial flora was recorded. In the group of the patients treated with the antibiotics prophylactically (group 1) the complications were 2.6 times more frequent than in the patients treated with pathogenetic agents alone (group 2). Intrahospital pneumonia developed in 8.9 per cent of the patients in group 1 and in 1.5 per cent of the patients in group 2. Therefore, antibiotics should not be used at the late periods of pertussis for prophylaxis of secondary bacterial complications. 相似文献
4.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals. 相似文献
5.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
6.
7.
Victor A. Sorokin Olga A. Antonova Vladimir A. Valeev 《Journal of inorganic biochemistry》1984,20(4):299-311
The effect ot Cu2+ and Ca2+ ions, on the ultraviolet differential (UVD) spectra of single-stranded poly I was studied and the coordination (Δεb) and conformation (Δεc) conponents of the spectra calculated The comparison of Δεb and the UVD spectrum of protonated IMP leads to the conclusion that N(7) ot inosine-5'-monophosphate (IMP) is a coordinating site tor Ca2+ and Cu2+ ions on the polymer bases. The binding ot Ca2+ and Cu2+ ions causes differently directed displacements of the four absorption bands of poly I, which are observed in the wavenumber range (50-34) × 103 cm−1 The calculation of concentration dependencies tor the association constants (K“) ot Ca2+ and Cu2+ ions binding to poly I bases shows that the binding is cooperative The K“ values for the poly I + Ca2+ complex are two orders of magnitude lower than those for the poly 1 + Cu2+ complex At low ion concentrations, binding to the poly I phosphates predominates and increases the degree of the polynucleotide helicity. At higher concentrations the spectra are mainly affected by the ion binding to bases, which results in melting of the helical parts of poly I At Ca2+ concentrations exceeding 10−3 M light-scattering aggregates are formed. The degree of monomer order in them is close to that observed in multistranded helices of poly I 相似文献
8.
Interstitial cells of the renal papilla have the phenotypic appearance, being more of a fibroblast than of a histiocyte character. Interstitial cells differ from the "typical fibroblasts" in the number of lipid droplets, in the development of cisternae of the Golgi complex and rough endoplasmic reticulum, and in the number of lysosome-like bodies and mitochondria. 相似文献
9.
L B Hejfets L A Levina L V Salmin A A Antonova L S Segal M L Kuzminova K M Slavina A V Vasileva 《Journal of hygiene, epidemiology, microbiology, and immunology》1976,21(3):292-299
A total of 3 controlled field trials were carried out. One of them (1963) showed that aerosol chemical typhoid vaccine did not protect vaccinated subjects from the disease. Two other tests (1964 and 1965) assessing the effectivity of killed orally administered typhoid vaccine revealed a short term (up to 3 months) protective effect expressed by an effectivity coefficient of 45%, fiducial limits being 8-70%. In the assessment of oral paratyphoid B vaccine, the difference in morbidity in the experimental and control groups was statistically insignificant due to a small number of cases of disease. 相似文献
10.
Etherification of butanol by acetic anhydride in butanol-butyl acetate mixtures containing 0.09 to 3 per cent water was investigated. A method for processing the butanol-butyl acetate mixtures with the weight part of butanol up to 16 per cent by etherification of the latter with acetic anhydride was developed, the yield being 96 to 97 per cent and the weight part being at least 97.5 per cent. On the basis of the estimate of the raw material use for regeneration of butyl acetate from the butanol-butyl acetate solutions by etherification of butanol with acetic anhydride, the technical and economic advantages of the processing of such solutions by the described method were shown. 相似文献