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A tentative survey on selected marine fish farms was undertaken to delineate the extent to which infections with Staphylococcus species occur in Turkish aquaculture systems. To determine the presence and the distribution of fish pathogenic staphylococci, representative farm types such as marine cages as well as inland pond farms working with saline-ground water and a large hatchery were selected. Field sampling was performed in a total of 13 commercial fish farms that are located in the most-popular aquaculture sites of Turkey. Samples were taken between October 2013 and August 2014. Almost all size classes of the most commonly marine cultured fish species in Turkey were investigated, including Dicentrarchus labrax, Sparus aurata, Argyrosomus regius, Diplodus puntazzo, Dentex dentex, Onchorhynchus mykiss and Salmo labrax. After a visual check, specimens with various clinical signs were sampled for bacteriological and histopathological investigations. Mixed infections of staphylococci along with Vibrio and Aeromonas representatives were detected in Dicentrarchus labrax, Sparus aurata and Diplodus puntazzo samples obtained from 7 farms. The following pathogens were identified: Staphylococcus. epidermidis, S. aureus, S. capitis subsp. capitis, S. lentus, S. hominis subsp. hominis and S. sciuri subsp. sciuri. Main clinical and histopathological effects of the infections in fishes were revealed. The pathogenicity of some isolates was confirmed with in vivo pathogenicity assay and SDS-PAGE analysis.  相似文献   
73.
The ‘choice’ of whether to enter diapause or to develop directly has profound effects on the life histories of insects, and may thus have cascading consequences such as seasonal morphs and other less obvious forms of seasonal plasticity. Present knowledge of the control of diapause and seasonal morphs at the physiological and molecular levels is briefly reviewed. Examples, mainly derived from personal research (primarily on butterflies), are given as a starting point with the aim of outlining areas of research that are still poorly understood. These include: the role of the direction of change in photoperiod; the role of factors such as temperature and diet in modifying the photoperiodic responses; and the role of sex, parental effects and sex linkage on photoperiodic control. More generally, there is still a limited understanding of how external cues and physiological pathways regulating various traits are interconnected via gene action to form a co‐adapted complete phenotype that is adaptive in the wild despite environmental fluctuation and change.  相似文献   
74.
The development, survival and reproduction of the cabbage aphid, Brevicoryne brassicae (L.) were evaluated at three constant temperatures (20, 25 and 30°C) on cabbage, cauliflower, red cabbage, turnip and radish. The development periods of immature stages ranged from 10.7 d at 20°C to 7.60 d at 30°C for red cabbage. Total percentages of survivorship of immature stages varied from 39.40 and 82.50 within the temperature range of 25–30°C on radish. The average progeny per female was 31.15, 28.95 and 23.77 at 20, 25 and 30°C on cabbage.  相似文献   
75.
The possibilities of using gene therapy for bone regeneration have been extensively investigated. Improvements in the design of new transfection agents, combining vectors and delivery/release systems to diminish cytotoxicity and increase transfection efficiencies have led to several successful in vitro, ex vivo and in vivo strategies. These include growth factor or short interfering ribonucleic acid (siRNA) delivery, or even enzyme replacement therapies, and have led to increased osteogenic differentiation and bone formation in vivo. These results provide optimism to consider use in humans with some of these gene-delivery strategies in the near future.  相似文献   
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The etiopathogenesis of Graves’ disease (GD) has not been clearly elucidated although the role of chronical inflammation and endothelial dysfunction has been established. Adhesion molecules such as intercellular adhesion molecule 1 (ICAM1), vascular cell adhesion molecule 1 (VCAM1), and E-selectin are secreted from vascular endothelium and promote accummulation of leukocytes in damaged endothelial areas. This study examined the possible association of ICAM1 (G241R and K469E), VCAM1 (T-1591C and T-833C), and E-selectin (S128R) single nucleotide polymorphisms (SNPs) with the occurence of GD. ICAM1 (G241R and K469E), VCAM1 (T-1591C and T-833C), and E-selectin (S128R) SNPs in DNA from peripheral blood leukocytes of 171 patients with GD and 259 healthy controls were investigated by real-time PCR combined with melting curve analysis using fluorescence-labeled hybridization probes. We did not find significant differences in the distributions of studied polymorphisms, nor in the haplotype frequencies between patients with GD and healthy control. However, the anti-TPO levels in E-selectin 128R allele carrying subjects (SR + RR) were higher than S128S genotype (p < 0.05). In addition, the decline of TSH levels was more prominent in ICAM1 469 E carrying subjects (KE + EE) in comparison with wild homozygotes (p < 0.05). Although there is not assosiation between ICAM1 (G241R and K469E), VCAM1 (T-1591C and T-833C), and E-selectin (S128R) SNPs and susceptibility to GD, higher anti-TPO in E-selectin 128 SR + RR, and lower TSH in ICAM1 469 KE + EE subjects suspect that these genotypes are prone to increased antithyroid autoantibody production with more accentuated TSH suppression in GD. Further studies with a larger cohort, analyzing other polymorphisms in ICAM, VCAM1 and E-selectin genes are necessary to support our observations.  相似文献   
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Summary

Pheromones can be used as attractants for the opposite sex in many environments; however, little is known about the search strategies employed in responding to pheromones in the marine environment. The spawning behavior of males of the polychaete Nereis succinea is known to be triggered at close range by a high concentration (>~10?7 M) of pheromone, cysteine glutathione disulfide (CSSG), released by females. Since CSSG also causes acceleration of swimming and increased turning, in addition to eliciting ejaculation, we proposed the hypothesis that these behaviors elicited by low concentrations of pheromone can be used by males to find females. The current study develops a computer simulation model of male and female N. succinea behavior for testing whether male responses to low concentrations of CSSG can facilitate finding females. Video recording of female swimming behavior in the field showed spontaneous loops, spirals, and circles that have been incorporated into the model. The scientific workflow paradigm within which the computer model has been developed also incorporates a data provenance system to enable systematic replay and testing of responses to individual parameters. Output of the model shows complex turning behavior leading to successful mating encounters at concentrations as low as 3×10?9 M CSSG. Behavior resembling the output of the model was recorded in field observations. Application of the model in the future will be used to determine what pheromone concentrations produce significant increases in the probability of mating encounters.  相似文献   
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