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91.
Physiologic changes occurring in the thyroid in response to the estrous cycle have been noted in companion animals. However, in bottlenose dolphins, the influence of different reproductive states on thyroid morphology remains unclear. Sonography was used to evaluate the variations of thyroid morphology for nine consecutive estrous cycles of four sexually mature, female Indo-Pacific bottlenose dolphins (Tursiops aduncus). The estrous cycle was divided into two phases for evaluation: the follicular and luteal phases. To compare changes associated with sex, thyroid volumes were measured in the different phases during the estrous cycle of female dolphins and were compared to the ultrasound examinations of the four male dolphins measured over a 2-mo period. In males, there was no significant difference in thyroid volume during the study period (P > 0.05). The thyroid volume measured in combining all estrous cycle phases of the female dolphins was significantly larger than that measured in the male dolphins (P < 0.05). A difference in thyroid volume during the estrous cycle was observed, with the thyroid volume during the follicular phase significantly smaller (P < 0.05) than that of the luteal phase, and is possibly related to the influence of female sex steroids. Thyroid volume variability during estrus should, therefore, be taken into account when examining the thyroid gland of female dolphins.  相似文献   
92.
A protease produced by Staphylococcus aureus, isolated from a chicken suffering from dermatitis, was purified by successive precipitation with ammonium sulfate, ion-exchange chromatography on Q-Sepharose FF, Sp-Sepharose FF and Mono-Q columns. By Mono-Q column chromatography, two proteases (protease 1 and 2) were obtained. The molecular weights of protease 1 and 2 were estimated at 23.1 and 22.7 kDa, respectively, by SDS-polyacrylamide gel electrophoresis. Their isoelectric points were 5.85 and 5.55, respectively, and they possessed antigenic similarity when examined by the immunoblotting. The N-terminal amino acid sequences of both the proteases were identical (RAQYVNQLKNFKIRETQ). The activities of both the proteases were strongly increased by reducing agents such as L-cysteine and sodium thioglycolate. Their activity was inhibited by thiol protease inhibitors, but was not inhibited by metalloprotease or serine protease inhibitors. From the results, it seems likely that these proteases, produced by S. aureus from diseased chickens, might belong to the thiol protease group.  相似文献   
93.
This study aims to reveal the first report of the natural spawning of F1 hybrid grouper (TGGG), a crossbreed between the tiger grouper, Epinephelus fuscoguttatus × giant grouper, E. lanceolatus, since its first production in 2006. This marks the completion of its full cycle after a 10-year period. In order to establish a seed rearing protocol for a novel F2 hybrid TGGG, natural spawning, embryonic and larval developments were thoroughly observed. Five batches of natural spawning were recorded with an average of 1.50–15.3 kg eggs collected, while fertilization and hatching rates were recorded at 85.3–97.6%, and 63.0–98.3%, respectively. F2 larvae hatched out at 17:50 hours with an average body size of 1.74 ± 0.01 mm, and a yolk sac volume of 0.85 ± 0.197 mm3. The first feeding was initiated 3 days after hatching, which coincided with the onset of functional feeding apparatus and active swimming behavior. Larval dorsal and pelvic spines were formed at 6 days AH coupled with dynamic feeding activity, as more food was found in the digestive tract. Meanwhile, the F2 hybrid grouper shifted habitat from pelagic to benthic as early as 25 days AH, and entered a juvenile stage at 35 days AH, attaining a skin coloration similar to that of the F1 juvenile. This study concluded that naturally spawned eggs of F2 hybrid TGGG were exceptionally high in quality, although larvae were small and fragile, and performed vigorous feeding activities and cannibalistic behavior. Thus, these findings can serve as primary data to further develop the optimal rearing protocol to enhance the overall rearing performance.  相似文献   
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Amino acid changes in Pepper mild mottle virus (PMMoV) coat protein (CP) that enhance, decrease, or nullify the resistance-inducing activity in Capsicum plants carrying the L 3 gene have been identified. In this study, molecular events underlying the L 3 -gene-mediated resistance were analyzed through the expression of hypersensitive response (HR)-related genes, HSR203J-Cc and HIN1-Cc, and defense-related genes, PR1-Cc and PR4b-Cc, upon infection with PMMoV CP mutants. The expression kinetics of the genes correlated with the degree of restriction of virus distribution in the inoculated leaves. The results suggest that the timing and extent of HR are critical factors to restrict virus spread both locally and systemically in L 3 -gene-mediated resistance.The nucleotide sequence data reported are available in the DDBJ/GenBank/EMBL databases under accession numbers AB162220 (HSR203J-Cc), AB162221 (HIN1-Cc), AB162222 (PR1-Cc), and AB162223 (PR4b-Cc)  相似文献   
97.
A new isolate of Tomato yellow leaf curl virus (TYLCV) has been identified from tomato plants in Kochi Prefecture in Japan and designated TYLCV-[Tosa]. The complete nucleotide sequence of the isolate was determined and found to consist of 2781 nt. In phylogenetic analyses of entire nucleotide sequences, TYLCV-[Tosa] was delineated as a single branch and was more closely related to TYLCV-[Almeria] than TYLCV isolates Ng, Sz, or Ai reported in Japan, which had spread since 1996. Isolate TYLCV-[Tosa] is suggested to be a newly introduced, novel isolate of TYLCV that dispersed into Kochi Prefecture. In addition, a rapid method using the polymerase chain reaction to separate TYLCV isolates into four genetic groups was established. This method would be useful for reliable diagnosis based on genetic differences among isolates of TYLCV.The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession numbers AB192965 and AB192966  相似文献   
98.
To clarify the role of fibronectin (FN) during the early period of feather development, reconstituted skin consisting of intact epithelium and isolated mesenchymal cells from embryonal chick skin was used. In early feather development, FN was localized around mesenchymal cells of the dermal condensation. Isolated mesenchymal cells had associated with FN on their surfaces. FN on the cell surface dissociated following EDTA treatment, and EDTA‐treated cells re‐associated with exogenous FN. The intact epithelium also bound to exogenous FN at the placode. When FN‐associated or FN‐reassociated mesenchymal cells were used, the reconstituted skin formed feather rudiments only at the positions where the epithelial placode existed originally, and the locality of tenascin transferred from the placode to the mesenchyme during the period of feather bud formation. However, in reconstituted skin using FN‐dissociated mesenchymal cells, feather rudiments did not form. Additionally, the epithelial placodes disappeared, and tenascin was distributed uniformly on the surface of the epithelium and not localized in the mesenchyme. These findings suggest that FN associated on the surfaces of mesenchymal cells maintains the functions of mesenchymal cells as dermal condensation and mediates epithelial‐mesenchymal interactions during the early period of feather development. The results also suggest that reconstituted skin is a useful tool for functional studies on the extracellular matrix.  相似文献   
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Fatty acids and their derivatives play a role in the response to ocular disease. Our current study investigated the effects of dietary mead acid (MA, 5,8,11-eicosatrienoic acid) supplementation on N-methyl-N-nitrosourea (MNU)-induced cataract and retinal degeneration in Sprague-Dawley rats. Experiment 1 was designed to inhibit cataract formation, with the dams fed a 2.4% MA or basal (<0.01% MA) diet during lactational periods. On postnatal day 7, male pups received a single intraperitoneal (ip) injection of 50 mg/kg MNU or vehicle. Lens opacity and morphology were examined 7 and 14 days after the MNU injection. Experiment 2 was designed to inhibit retinal degeneration and was performed with female postweaning rats. In this experiment, dams were fed the 2.4% MA or basal diet during the lactational periods. Thereafter, the female pups were continuously fed the same diets during their postweaning periods. On postnatal day 21 (at weaning), pups received a single ip injection of 50 mg/kg MNU. Retinal morphology was examined 7 days after the MNU injection. In experiment 3, six-week-old female rats were fed the 2.4% MA or basal diet starting at one week before the MNU injection and were then continuously fed the same diets until sacrifice. Rats at 7 weeks of age were given a single ip injection of 40 mg/kg MNU, and the retina was then examined morphologically one week after the MNU injection. In experiment 1, mature cataract was found in all of the MNU-treated groups, with or without MA supplementation. In experiments 2 and 3, atrophy of both the peripheral and central outer retina occurred in all rats exposed to MNU, with or without MA supplementation, respectively. The severities of the cataracts and retinal atrophy in the rats were similar regardless of MA supplementation. Dietary mead acid, which is used as a substitute in essential fatty acid deficiency in the body, does not modify MNU-induced cataract and retinal degeneration in rat models.  相似文献   
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