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991.
Katarzyna Szyba Maria Cieślak Golonka Kazimierz Gasiorowski Joanna Urban 《Biometals》1992,5(3):157-161
Copper(II) chromate and dichromate complexes with 2,2'-bipyridyl and 1,10-phenathroline were tested for their mutagenic activity in the standard Ames test. All of six tested complexes exhibited markedly lower mutagenic activity than the reference compounds--potassium dichromate and sodium chromate. The blockage of Cr(VI) reduction capability in the presence of the complex Cu2+ ion and the competition between copper and chromium ions in the interaction with cellular components are discussed in the light of the results of our previous chemical study. 相似文献
992.
993.
金黄色萄葡球菌L型特异性抗体的免疫组化试验在妇科感染性疾病诊断上的应用 总被引:1,自引:1,他引:0
本文对49例慢性子宫内膜炎、慢性宫颈炎等妇科疾病的病理切片,用金黄色葡萄球菌细菌型及L型的特异性杭体作酶免疫组化染色(PAP法)证明在金黄色葡萄球菌引起的各种妇科感染中,细菌型及L型混合感染占60%,单独细菌型感染占28.9%,单独L型感染占11.1%。本研究证明了金葡菌变异为L型后,有特异性杭原出现,并证明细菌L型的特异性抗原有一定的免疫学诊断价值。 相似文献
994.
In the Vecht river plain, the vegetation diversity has been diminished during recent decades, due to hydrological changes and resulting eutrophication. Different options are discussed for hydrological management aimed at abating the eutrophication and at stimulating the characteristic mesotraphent succession phases of the fen vegetation. The ecological impact of the management plans are estimated with the hydro-ecological model ICHORS; this model takes into account the relations between the non-biotic environment and the presence of hydrophytes and phreatophytes. The impact of the hydrological options is assessed, after rearrangement of the predicted values of the species to values of the required fen vegetation. These results are incorporated in the management options with the water balances of the polders. Information on the costs of the options is used as a basis for a cost-benefit analysis. Technical hydrological solutions such as purification of the supplied water might contribute to the eutrophication abatement, but they are on their own unlikely to restore the ecosystems. Contrastingly, options involving the restoration of the original hydrology would probably lead to the characteristic mesotraphent fen vegetation once more, and the financial implications of this are likely to be the more favourable in the long-term. 相似文献
995.
Junsei Taira Takeshi Ikemoto Tohru Yoneya Akifumi Hagi Akira Murakami Keisuke Makino 《Free radical research》1992,16(3):197-204
In order to search for radical scavengers which could be used as raw materials for cosmetics, phenyl propanoids (eugenol, isoeugenol, dehydrodieugenol, dehydrodieugenol B and coniferyl aldehyde) were examined for their hydroxyl radical (· OH) scavenging ability. A Fenton system was used to produce -OH. In order to see scavenging by these phenyl propanoids, competition reactions between a spin trap, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), and these phenyl propanoids for -OH were studied. The relative yield of the spin adduct of -OH (DMPO-OH) was measured by electron spin resonance spectroscopy. The approximate rate constants of the reactions between these phenyl propanoids and -OH estimated by measuring the reduced height of the ESR signals of DMPO-OH were found to be at least in the order of 109 M-1 s-1 (diffusion-controlled). Also, using the TBA tests, the reactions between ·OH and several compounds reactive with ·OH were investigated in the presence of the phenyl propanoids and it was found that the phenyl propanoids compete with such reactive compounds for ·OH. These results indicate that these phenyl propanoids can be used as antioxidants for skin damage perhaps caused by -OH generated by UV-light. 相似文献
996.
A. Roy N. Frascaria J. MacKay J. Bousquet 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1992,85(2-3):173-180
Summary Molecular markers are currently being developed for Betula alleghaniensis Britton using random amplified polymorphic DNA (RAPD). Arbitrarily designed 11-mer primers were tested on three intraspecific controlled crosses for which more than 15 full-sibs were available. Using two of these primers, we were able to genetically characterize a total of nine polymorphic RAPD markers. Segregation of these markers was consistent with a biparental diploid mode of inheritance, and all appeared dominant. RAPDs were valuable in detecting contaminants and, therefore, in assessing the validity of controlled crosses. Limitations of the technique are discussed in relation to the determination of parental genotypes and construction of linkage maps for hardwood species. 相似文献
997.
Tomomasa Watanabe Yuka Sakai Shigeki Miyawaki Atsuko Shimizu Osamu Koiwai Kyoko Ohno 《Biochemical genetics》1991,29(7-8):325-335
The mouselpr gene, which is an autosomal recessive gene causing autoimmune disease with features of human systemic lupus erythematosus and eventually death from severe immune-complex glomerulonephritis, has been mapped on chromosome 19. To determine its exact chromosomal location, a three-point backcross was carried out by mating (MRL/MpJ-lpr/lpr × MOL-MIT)F1 × MRL/MpJ-lpr/lpr using the genesLy-44 (lymphocyte differentiation antigen-44) andTdt (terminal deoxynucleotidyl transferase) as markers. The following order of genes is proposed, with the distances between genes given in parentheses: centromere-Ly-44 (19.3 cM)-lpr (6.1 cM)-Tdt-telomere. TheLy-44
a
andTdt
a
alleles are found in all laboratory strains and in the wild Western European subspecies,domesticus andbrevirostris. In contrast, theLy-44
b
andTdt
b
alleles are found in some Asian subspecies, Chinese mice of wild origin,yamashinai andmolossinus. Furthermore the thirdTdt allele,Tdt
c
, is detected incastaneus.Some of the data in this study were previously presented at the 4th Mouse Gene Mapping Workshop, Annapolis, Maryland, in November 1990. 相似文献
998.
999.
Sequential Monte Carlo p-values 总被引:4,自引:0,他引:4
1000.
M. Mazor M. Harel S. Levsky E. Dunkelblum 《Entomologia Experimentalis et Applicata》1991,60(2):167-172
Capillary gas chromatography indicated the presence of (Z)-7-dodecenyl alcohol and (Z)-7-dodecenyl acetate in the abdominal tip extracts of female Cornutiplusia circumflexa (L.) (Lepidoptera: Noctuidae: Plusiinae) moths. Gas chromatography combined with mass spectrometry and dimethyl disulfide derivatization confirmed the structure of these two principal pheromone components. In a flight-tunnel bioassay, a 5:1 blend of alcohol and acetate elicited the complete courtship sequence by males. The response was comparable to that evoked by a live virgin female, but males spent significantly longer time at calling females than at the synthetic source. The 5:1 blend was also attractive to male C. circumflexa in the field, as indicated by catches in traps baited with this mixture. (Z)-7-dodecenyl alcohol alone was slightly attractive whereas (Z)-7-dodecenyl acetate alone was completely inactive. C. circumflexa is the first reported Plusiinae species which utilizes (Z)-7-dodecenyl alcohol as the major pheromone component. 相似文献