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191.
Martin B Possémé F Le Barbier C Carreaux F Carboni B Seiler N Moulinoux JP Delcros JG 《Bioorganic & medicinal chemistry》2002,10(9):2863-2871
Polyamine vectors are attractive for tumor targeting. We envisaged (Z)-1,4-diamino-2-butene (Z-DAB), an unsaturated analogue of putrescine as vector of (10)B, (18)F and (131)I for boron neutron capture therapy (BNCT), and tumor imaging by positron emission tomography or scintigraphy respectively. In the present work, the synthesis and characterization of new derivatives of Z-DAB were reported. Z-DAB was actively transported in cells via the polyamine transport system and converted into the spermidine analogue.(E)-2-iodo-1,4-diamino-2-butene (E-I-DAB) was not taken up by the polyamine transport system and may not be suitable for tumor imaging. In contrast, (Z)-2-[4-(5,5-dimethyl-dioxaborinan-2-yl)phenyl]methyl-1,4-diamino-2-butene (Z-4-Bbz-DAB) was a substrate of the transport system and allowed significant boron accumulation in 3LL cells. Its potential in BNCT will be evaluated. 相似文献
192.
Ward AJ Botham MS Hoare DJ James R Broom M Godin JG Krause J 《Proceedings. Biological sciences / The Royal Society》2002,269(1508):2451-2455
We investigated pairwise association patterns and shoal fidelity in free-ranging, individual three-spine sticklebacks (Gasterosteus aculeatus) by capturing entire shoals of sticklebacks and tagging each shoal member with a unique individual mark before releasing the shoal at the point of capture. We recaptured tagged fishes in the study area on five subsequent days, noting their identity, their location and the individuals with which they were associated. Stable partner associations between fishes were observed which might provide the basis for shoal fidelity via social networks. These results suggest the potential for the kinds of inter-individual association patterns assumed by models of predator inspection and 'tit-for-tat' behaviours in free-ranging fishes. 相似文献
193.
Drew J. Hoysak & Jean-Guy J. Godin 《Ethology : formerly Zeitschrift fur Tierpsychologie》2007,113(10):1007-1018
Male mate choice has evolved in many species in which female fecundity increases with body size. In these species, males are thought to have been selected to favour mating with large females over smaller ones, thereby potentially increasing their reproductive success. While male mate choice is known to occur, it is less well studied than female mate choice and little is known about variation in mating preference among individual males. Here, we presented individual male eastern mosquitofish ( Gambusia holbrooki ) with paired females that differed in body size, and we quantified their mate preference on two consecutive days, allowing us to assess repeatability of preferences expressed. When males were allowed to view paired stimulus females, but not to acquire chemical or tactile cues from them, they exhibited a strong preference for large females over smaller ones. However, individual males were not consistent in the strength of their preference and repeatability was not significant. When individual males were allowed to fully interact with pairs of females, the males again exhibited a preference for large females over smaller ones, as revealed by a greater number of attempted copulations with large females than with smaller ones. In the latter social context, individual male preference was significantly repeatable. These results indicate that male eastern mosquitofish from our Florida study population possess, on average, a mating preference for larger females and that this preference is repeatable when males socially interact freely with females. The significant repeatability for mating preference, based on female body size, obtained for male mosquitofish in the current study is consistent with the presence of additive genetic variation for such preferences in our study population and thus with the opportunity for the further evolution of large body size in female mosquitofish through male mate choice. 相似文献
194.
Intraspecific Genotypic Characterization of Lactobacillus rhamnosus Strains Intended for Probiotic Use and Isolates of Human Origin 下载免费PDF全文
M. Vancanneyt G. Huys K. Lefebvre V. Vankerckhoven H. Goossens J. Swings 《Applied microbiology》2006,72(8):5376-5383
A set of 118 strains of the species Lactobacillus rhamnosus was collected, including probiotic strains, research strains with potential probiotic properties, food starter cultures, and human isolates. The majority of the strains were collected from companies, hospitals, or culture collections or were obtained after contacting authors who reported clinical case studies in the literature. The present work aimed to reveal the genotypic relationships between strains of these diverse sources. All strains were initially investigated using fluorescent amplified fragment length polymorphism (FAFLP) with three different primer combinations. Numerical analysis of FAFLP data allowed (i) confirmation of the identification of all strains as members of L. rhamnosus and (ii) delineation of seven stable intraspecific FAFLP clusters. Most of these clusters contained both (potentially) probiotic strains and isolates of human origin. For each of the clusters, strains of different sources were selected for pulsed-field gel electrophoresis (PFGE) of macrorestriction fragments obtained with the enzymes NotI and AscI. Analysis of PFGE data indicated that (i) some (potentially) probiotic strains were indistinguishable from other probiotic strains, suggesting that several companies may use duplicate cultures of the same probiotic strain, and (ii) in a number of cases human isolates from sterile body sites were indistinguishable from a particular probiotic strain, suggesting that some of these isolates may be reisolations of commercial strains. 相似文献
195.
Fluorescent Amplified Fragment Length Polymorphism and Repetitive Extragenic Palindrome-PCR Fingerprinting Reveal Host-Specific Genetic Diversity of Vibrio halioticoli-Like Strains Isolated from the Gut of Japanese Abalone 下载免费PDF全文
Tomoo Sawabe Fabiano L. Thompson Jeroen Heyrman Margo Cnockaert Karin Hayashi Reiji Tanaka Mamoru Yoshimizu Bart Hoste Jean Swings Yoshio Ezura 《Applied microbiology》2002,68(8):4140-4144
When analyzed by fluorescent amplified fragment length polymorphism and repetitive extragenic palindrome-PCR fingerprinting, a total of 47 Vibrio halioticoli strains isolated from four Japanese abalone species and one turban shell species formed three clusters that roughly reflect the different species of host abalone from which they were isolated. The V. halioticoli isolates from turban shells were distributed evenly among the clusters. Representative isolates from two clusters were deemed separate species or subspecies by DNA-DNA hybridization. 相似文献
196.
Characterization of Further Erwinia amylovora Strains and the Application of the API 20E System in Diagnosis 总被引:1,自引:0,他引:1
The former phenotypic study of Erwinia amylovora (VANTOMME et al. 1982) was extended with a collection of 54 Erwinia amylovora strains from a broad plant and geographic origin. From the 85 phenotypic features studied, 72 (85%) were present in at least 90% of the strains. Only 49 (58%) of the features were shared by all strains. Thirty-eight strains were also examined by the API 20E system. The API 20E code numbers for E. amylovora are unique and, combined with an immature, (green) pear test, may be used for an accurate identification of Erwinia amylovora. 相似文献
197.
198.
Nineteen phytopathogenic fluorescent Pseudomonas isolates were isolated from diseased witloof chicory (Cichorium intybus L. var. foliosum Hegi). They were compared with six Ps. fluorescens strains from culture collections, using SDS-PAGE of total cell proteins. The fluorescent pseudomonads examined showed seven different fingerprint types. The major group of phytopathogenic fluorescent pseudomonas revealed a fingerprint type which was frequently found on healthy chicory roots and leaves too. Some, but not all, of the isolates from healthy plants produced typical disease symptoms upon artificial inoculation of etiolated chicory leaves. Infectivity titrations showed a reduced efficiency of the latent pathogen PGSB-7228 to cause disease symptoms on the chicory leaves. The virulence of the latent pathogen is induced in the presence of wounded chicory tissue. 相似文献
199.
200.