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Agrobacteria were previously isolated from tumors developing on branches and aerial and hypogeous roots of weeping fig plants in Italy and in The Netherlands. A representative group of 48 strains was analyzed by PCR–RFLP of 16S and 16S + IGS ribosomal regions, PCR–RFLP of six Ti plasmid (pTi) regions and characterized for plasmid content. Two groups of agrobacteria were separated by cluster analysis of PCR–RFLP profiles of rrs gene: seventeen strains were similar to the new species Agrobacterium larrymoorei, while the remaining strains were included within the agrobacterium biovar 1 group. Sixteen different plasmid profiles from one to five plasmids were observed. In addition, 21 ribotypes and 20 pTi structures were arranged in many different combinations, showing that fig agrobacteria were characterized by a wide heterogeneity. A general lack of correlation between strain ribotypes and plasmid content was observed.  相似文献   
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A 7.5-year-old castrated male ferret (Mustela putorius furo) was diagnosed with third-degree atrioventricular (AV) block. A monopolar epicardial pacemaker system was implanted, resulting in a regular, paced cardiac rhythm with third-degree AV block at 140 beats per minute. Over the next 2 months, the ferret developed anorexia, interstitial pneumonia, intermittent diarrhea, and hind-limb weakness and had a slow and progressive recovery. The ferret developed clinical signs of congestive heart failure 4 months after the surgery, resulting in its death 3 weeks later. Necropsy results attributed the death to cardiac failure due to extensive myocardial mineralization. To the authors' knowledge this is the first published report of surgical report of surgical pacemaker implantation in a ferret.  相似文献   
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The ability of phaseolin to act as an acyl donor and acceptor substrate of transglutaminase was studied by using an enzyme isolated from Streptoverticillium mobarense. Phaseolin, a trimeric storage protein from Phaseolus vulgaris L., was shown to possess both glutamine and lysine residues reactive for the enzyme. The extent of transglutaminase-catalyzed cross-linking has been studied in function of both incubation time and enzyme concentration. Native- and SDS-PAGE demonstrated that phaseolin is intra- and intermolecularly cross-linked by transglutaminase and gives rise to different polymers as well as to modified forms of the protein having a similar molecular weight but lower Stokes radius if compared to unmodified phaseolin. Cross-linked phaseolin was found to be more resistant to proteolytic cleavage than the unmodified counterpart, as demonstrated by in vitro trypsin and pepsin digestion experiments. This behavior could suggest novel possible uses of the transglutaminase-modified phaseolin.  相似文献   
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European Journal of Forest Research - The growing interest in accessing steep terrain is pushing the expansion of the operating range of ground-based machines through winch-assist technology....  相似文献   
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The application of artificial insemination techniques as a way to overcome the lack of mating of the closed thelycum Farfantepenaeus paulensis under large scale conditions is reported. The performance of artificially inseminated females (49.4±11.6 g) maintained in conventional versus unisex maturation systems was compared. Groups of unilaterally eyestalk-ablated females were artificially inseminated with one compound spermatophore soon after molting. The percentage of fertilized spawns increased from 26% before the use of artificial insemination to 57% afterwards. The reproductive performance of inseminated females held in conventional or unisex maturation systems showed no significant differences. Artificial insemination was considered a practical approach to overcome the lack of mating of F. paulensis under large-scale conditions with acceptable reproductive performance. The results also indicate the possibility of holding females separately from males, which could mean significant improvements in maturation systems through the increase in the stocking density of spawning females.  相似文献   
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The reproduction of wild-caught Farfantepenaeus paulensis in captivity has been successfully achieved since 1983. However, year-round supply of wild broodstock is costly and unpredictable. This study compares the reproductive performance of animals of similar size (females from 32–33 g and males from 19–21 g) but from different sources: estuary-caught juveniles reared indoors for 9 mo and wild-caught adults from shallow coastal waters. Groups of 20 males and 30 unilaterally eyestalk-ablated females were maintained for 60 d in four maturation tanks under controlled environmental conditions. A higher number of eggs per spawning event (78,414 ± 34,491) and total egg production (4,469,600) were observed for the wild females. Nevertheless, captive females produced a higher number of nauplii (1,788,259) due to their higher percentage of fertilized spawns. Therefore, within the size range of this study, the reproductive performance of estuary-caught F. paulensis juveniles over-wintered indoors was found to be equivalent to that of wild-caught females from shallow coastal waters.  相似文献   
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Summary Eighty ten-base long arbitrary primers were tested for PCR-based DNA amplification of three species of the genus Actinidia (A. deliciosa the kiwifruit, A. chinensis, and A. kolomikta), with the aim of screening species-specific and genotype-specific markers.Of the 80 primers tested, 30 gave an average of 3.5 bands which were monomorphic within one or two species and absent in the remaining one(s), thus resulting in useful markers for taxonomic and phylogenetic purposes. None of the primers tested produced bands linked to sex. Twenty primers out of the twenty-five selected from a preliminary screening showed high levels of polymorphism, producing two to eleven patterns each from the 13 kiwifruit cultivars examined.We found the Stoffel fragment and the Taq polymerase were both suitable for RAPD analysis, the most noticeable difference being the smaller size of fragments (0.4–1.2 kb) produced by the former in comparison to the latter (1.0–3.4 kb). We tested also three different annealing temperatures (35, 37, and 39° C) and found the intermediate one best for number of amplified bands and reproducibility of results.Abbreviations 2-BE 2-butoxyethanol - CTAB hexadecyltrimethylammonium bromide - MAS Marker-Assisted-Selection - PCR Polymerase Chain Reaction - RAPD Random Amplified Polymorphic DNA - RFLPs Restriction Fragment Length Polymorphisms  相似文献   
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Southern populations of the European minnow fromremote oligotrophic mountain lakes along an Alpinenorth-south transect accumulated more p,p DDE andPCBs than northern populations. As these semi-volatileorganochlorines predominantly evaporate in warmcountries, higher rates of condensation (deposition)are assumed to occur in the southern slopes of theAlps. The higher accumulation of lead and cadmium insouthern population is rather attributed to geogenicand specific environmental impacts than to atmosphericdeposition. Increasing liver ratios of [glutathionedisulfide]/[glutathione], a potential indicator foroxidative stress, from north to south reflect thegenerally higher toxic load at remote sites at thesouthern edge of the Alps. However, histopathologicalchanges in the liver did not correlate withaccumulated toxicants indicating that deposition doesnot lead to severe lesions but induces specificmechanisms for detoxification.  相似文献   
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