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Nine pairs of polymerase chain reaction (PCR) primers that amplify polymorphic microsatellite loci in the desert locust, Schistocerca gregaria (Forskal), were developed using a magnetic bead‐based enrichment protocol. A sample of 48 locusts collected during the 1993 and 1995 upsurge periods in Eritrea, East Africa, were genotyped. The number of alleles per locus ranged from six to 20; the average was 12.67. Allelic distributions were significantly different between samples from different localities. 相似文献
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Localization of Surface Structures During Procaryotic Differentiation: Role of Cell Division in Caulobacter crescentus 总被引:18,自引:0,他引:18
EDWARD D. HUGUENEL AUSTIN NEWTON 《Differentiation; research in biological diversity》1982,21(1-3):71-78
Asymmetric cell division in Caulobacter crescentus produces two cell types, a stalked cell and a new swarmer cell, with characteristics surface structures. We have examined the role of the cell cycle in the differentiation of these two cells using the adsorption of bacteriophage øLC72, the assembly of the polar flagellum, and stalk formation as assays for changes in surface morphology. Previous studies of this aquatic bacterium [17, 25] have suggested that the replicating chromosome acts as a 'clock' in timing the formation of the flagellar filament at one pole of the new swarmer cell. The analysis of conditional cell cycle mutants presented here extends these results by showing that DNA synthesis is also required for adsorption of phage øLC72 and, more importantly, they also suggest that a late cell division step is involved in determining the spatial pattern in which the phage receptors and flagella are assembled. We propose that this cell division step is required for formation of 'organizational' centers which direct the assembly of surface structures at the new cell poles, and for the polarity reversal in assembly that accompanies swarmer cell to stalked cell development. 相似文献
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Maggot therapy: a review of the therapeutic applications of fly larvae in human medicine, especially for treating osteomyelitis 总被引:1,自引:0,他引:1
In traditional medical practice, the larvae of some Diptera: Calliphoridae, notably Lucilia illustris (Meigen), L.sericata (Meigen) and Phormia regina (Meigen), have been employed for maggot therapy, i.e. to help clean lesions antiseptically, especially for treatment of chronic osteomyelitis. This mode of treatment remains appropriate for cases where antibiotics are ineffective and surgery impracticable. 相似文献
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JOSEPH D. SCHWARTZMAN EDWARD C. KRUG LESTER I. BINDER MICHAEL R. PAYNE 《The Journal of eukaryotic microbiology》1985,32(4):747-749
Seven monoclonal antibodies specific for mammalian β-tubulin demonstrate the microtubule cytoskeleton of Toxoplasma gondii and Leishmania donovani by indirect immunofluorescence microscopy. Immunoblots of T. gondii and L. donovani proteins separated by SDS polyacrylamide gel electrophoresis confirm the specificity of the monoclonal antibodies for tubulin. Differential staining of flagellar and subpellicular microtubule populations was not seen in L. donovani with these antibodies. All seven antibodies also detected the subpellicular microtubules of T. gondii, but the polar ring and conoid of this organism was not visualized by any of them. This technique provides a rapid and specific way to assess microtubular organization in whole organisms. 相似文献
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Trifluralin inhibited root elongation and induced root tip swellingof Zea mays and Triticum aeslivum. Time-course experiments showedthese effects occurred within 6 hr of treatment. As the rootstreated with trifluralin enlarged, there was a concomitant increasein root growth inhibition. Bioassays were devised to quantitativelymeasure the radial enlargement of trifluralin-treated roots.Histological observations indicated that swollen root tissuewas growing in a non-polar manner. The root swelling effectof trifluralin was inhibited 70% by the reducing agent, 2,3-dimercaptopropanol.Trifluralin had no effect on SH content of root tip proteinof Z.mays.
1 Published with the approval of the Director of die West VirginiaAgricultural Experiment Station as Scientific paper No. 1177.
2 Present address: Department of Biology, Mercyhurst College,Erie, Pennsylvania 16501, U.S.A. (Received March 19, 1971; ) 相似文献
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Northern red oak (Quercus rubra L.) seedlings were grown for63 d in a complete nutrient solution (pH 3.8) containing oneof three concentrations of Al (0, 0.75 or 2-0 mol m3)and either 10 or 250 mmol m3 Ca. Of all solution variables,the In of (Al3+)/(Ca2+), the solution activities ratio, wasmost closely correlated with declines in shoot and root growth.Ln (Al3+)/(Ca2+) also most closely predicted leaf and root [Mg],[Al], and [Al]/[Ca]. These three variables in turn were closelyrelated to growth. Toxic levels of (Al3+) and (Al3+)/(Ca2+)in solution are compared to levels in forest soils. Key words: Al phytotoxicity, Al x Ca interaction, Quercus rubra 相似文献