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AIMS: To create a fast, sensitive and specific method for identifying Fusarium oxysporum f. sp. cucumerinum and F. o. luffae. METHODS AND RESULTS: Specific DNA bands were selected as probes from RAPD profiles of 13 formae speciales of F. oxysporum. The forma specialis-specific probe OPC18300c and OPC18520f could be used to identify F. o. cucumerinum and F. o. luffae by RAPD-PCR followed dot blot hybridization, respectively. CONCLUSIONS: A specific method for identifying F. o. cucumerinum and F. o. luffae was achieved. SIGNIFICANCE AND IMPACT OF THE STUDY: F. oxysporum formae speciales identification with a DNA probe can be relatively rapid and provides a method to identify the pathogen without host inoculation tests. 相似文献
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The exploratory and fear behaviours of the black paradise fish M. o. concolor, a subspecies of Macropodus opercularis, were studied and compared with those of an outbred and two inbred populations of M. o. opercularis. Adult females of both subspecies were used in the behaviour tests (open-field, novel-object approach, restricted space), and their behaviour in novel and startling situations was described by recording the sequence of ethologically defined units. It was found that M. o. concolor more often responded passively to novelty and fear-evoking stimuli. In 11 out of 14 test measures they were less active (p less than 0.01 and 0.001) than the outbred M. o. opercularis, but were very similar to our extremely timid strain P. Subtle differences of behaviour units were found between the subspecies, e.g. the absence of interrupted movements and unoriented panic behaviour in M. o. concolor. It is supposed that alternative passive and active strategies represent genetic polymorphism of defensive behaviour. 相似文献
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The sodium salts of the 6-sulfate 7, the 4-sulfate 10, and the 4,6-disulfate 12 of benzyl 3-O-(beta-D-glucopyranosyl uronate)-beta-D-galactopyranoside (5) have been synthesized. Methyl (2,3,4-tri-O-acetyl-1-bromo-1-deoxy-alpha-d-glucopyran)uronate (1) was coupled with benzyl 2-O-benzoyl-4,6-O-benzylidene-beta-D-galactopyranoside (2) to yield 3. The benzylidene acetal of 3 was hydrolyzed to give benzyl 2-O-benzoyl-3-O-[methyl (2,3,4-tri-O-acetyl-beta-D-glucopyranosyl)uronate]-beta-D-galactopyra noside (4). Compound 4 was utilized as a key intermediate to prepare the sulfated disaccharides 7,10, and 12. Direct sulfation of 4 with sulfur trioxide-trimethylamine for 2 days yielded the 6-sulfate 6. The 4,6-disulfate 11 was accessible by running the reaction under the same conditions for 14 days. The 4-sulfate 9 was obtained after protecting the 6-OH group of 4 by reaction with benzoyl imidazole to give the 6-benzoate 8, followed by sulfation under vigorous conditions. Treatment of the protected compounds 4, 6, 9, and 11 with aqueous sodium hydroxide in tetrahydrofuran gave the unprotected 5, 7, 10, and 12, respectively. 相似文献
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F Trovato 《Social biology》1992,39(1-2):82-101
For most people immigration to a new country such as Canada entails a positive move and an improvement in life. The many challenges associated with resettlement may, however, lead to insurmountable difficulties, stresses and conflict for a significant number of newcomers. The mortality experience of immigrants, as reflected in cause-of-death statistics, may provide indication of the extent of stress and conflict in their migration experience. This situation is most clearly exhibited in mortality from suicide, homicide, and motor vehicle accidents. In this study, hypotheses concerning immigrant mortality in Canada are developed and tested with a log-linear model for rates pertaining to rare events. Overall, the results give support for the importance of country-of-origin effects in explaining suicide propensities, but not for homicide and motor vehicle accidents mortality. Income discrepancies are a significant determinant of variability in death rates overall, but discrepancies between the immigrants in this study and the Canadian-born are not of much significance. The strongest net effect on the cause-specific death rate is associated with group membership. This effect likely reflects a number of residual unmeasured sources of variation including the influence of the immigrant ethnic community as a source of social support, and the potential confounding effects of migration selectivity. 相似文献
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T Dall-Larsen H Fasold L Klungsoyr H Kryvi C Meyer F Ortanderl 《European journal of biochemistry》1975,60(1):103-107
Adenosine-triphosphate-phosphoribosyl transferase from Escherichia coli reacts with S-dinitrophenyl-6-mercaptopurine-riboside 5'-phosphate. In this reaction the dinitrophenyl group becomes attached to the enzyme, while the nucleotide is split off. Most aliphatic high and low-molecular-weight-SH compounds react with the thioether in the opposite way, i.e. bind the nucleotide and split off dinitrothiophenol. It appears that the dinitrophenyl moiety of the thioether interacts with the enzyme in a specific way, and that this interaction activates the bond between the dinitrophenyl group and the sulfur atom. In support of this it was found that dinitrophenol inhibits the transferase reaction with half maximal effect at 0.4 mM. The inhibition is competitive with ATP. Dinitrophenol also competes with ATP in binding studies. 相似文献
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Jandir Mendona Nicacio Ricardo Khouri Antnio Marconi Leandro da Silva Manoel Barral-Netto Joo Augusto Costa Lima Ana Marice Teixeira Ladeia Rodrigo Feliciano do Carmo Anderson da Costa Armstrong 《PLoS neglected tropical diseases》2021,15(6)
BackgroundChikungunya fever (CHIKF) is a serious public health problem with a high rate of infection and chronic disabling manifestations that has affected more than 2 million people worldwide since 2005. In spite of this, epidemiological data on vulnerable groups such as Indigenous people are scarce, making it difficult to implement public policies in order to prevent this disease and assist these populations.ObjectiveTo describe the serological and epidemiological profile of chikungunya virus (CHIKV) in two Indigenous populations in Northeast Brazil, as well as in an urbanized control community, and to explore associations between CHIKV and anthropometric variables in these populations.Methodology/Principal findingsThis is a cross-sectional ancillary study of the Project of Atherosclerosis among Indigenous Populations (PAI) that included people 30 to 70 years old, recruited from two Indigenous tribes (the less urbanized Fulni-ô and the more urbanized Truká people) and an urbanized non-Indigenous control group from the same area. Subjects underwent clinical evaluation and were tested for anti-CHIKV IgG by enzyme-linked immunosorbent assay. Serological profile was described according to ethnicity, sex, and age. The study population included 433 individuals distributed as follows: 109 (25·2%) Truká, 272 (62·8%) Fulni-ô, and 52 (12%) from the non-Indigenous urbanized control group. Overall prevalence of CHIKV IgG in the study sample was 49.9% (216; 95% CI: 45·1–54·7). When the sample was stratified, positive CHIKV IgG was distributed as follows: no individuals in the Truká group, 78·3% (213/272; 95% CI: 72·9–83·1) in the Fulni-ô group, and 5.8% (3/52; 95% CI: 1.21–16) in the control group.Conclusions/SignificancePositive tests for CHIKV showed a very high prevalence in a traditional Indigenous population, in contrast to the absence of anti-CHIKV serology in the Truká people, who are more urbanized with respect to physical landscape, socio-cultural, and historical aspects, as well as a low prevalence in the non-Indigenous control group, although all groups are located in the same area. 相似文献
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L. Everard Napier 《BMJ (Clinical research ed.)》1946,1(4435):26-27
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The oxidation-reduction potentials of cytochrome o + c4 and cytochrome o purified from Azotobacter vinelandii. 总被引:2,自引:0,他引:2
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Oxidation-reduction titrations of Azotobacter vinelandii cytochrome o + c4 and cytochrome o were performed with simultaneous potential and absorbance measurements under anaerobic conditions. Cytochrome c4 has a midpoint potential (Em, 7.4) of 260mV and purified cytochrome o has an Em, 7.4 of -18mV. Little change in the midpoint potential of cytochrome o was observed when titrated in the pH range 6.2--9.8. 相似文献