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131.
The key biological active molecule of soya is the isoflavone daidzein, which possesses phytoestrogenic activity. The direct effect of soya and daidzein on ovarian cell functions is not known. This study examined the effect of daidzein on basic porcine ovarian granulosa cell functions and the response to follicle‐stimulating hormone (FSH). We studied the effects of daidzein (0, 1, 10 and 100 μm ), FSH (0, 0.01, 0.1, 1 IU/ml) and combinations of FSH (0, 0.01, 0.1, 1 IU/ml) + daidzein (50 μm ) on proliferation, apoptosis and hormone release from cultured porcine ovarian granulosa cells and ovarian follicles. The expression of a proliferation‐related peptide (PCNA) and an apoptosis‐related peptide (Bax) was analysed using immunocytochemistry. The release of progesterone (P4) and testosterone (T) was detected using EIA. Leptin output was analysed using RIA. Daidzein administration increased granulosa cell proliferation, apoptosis and T and leptin release but inhibited P4 output. Daidzein also increased T release and decreased P4 release from cultured ovarian follicles. Follicle‐stimulating hormone stimulated granulosa cell proliferation, apoptosis and P4, T and leptin release. The addition of daidzein promoted FSH‐stimulated apoptosis (but not proliferation) but suppressed FSH‐stimulated P4, T and leptin release. Our observations of FSH action confirm previous data on the stimulatory effect of FSH on ovarian cell proliferation, apoptosis and steroidogenesis and demonstrate for the first time the involvement of FSH in the upregulation of ovarian leptin release. Our observations of daidzein effects demonstrated for the first time that this soya isoflavone affected basic ovarian cell functions (proliferation, apoptosis and hormones release) and modified the effects of FSH. Daidzein promoted FSH action on ovarian cell proliferation and apoptosis and suppressed, and even inverted, FSH action on hormone release. The direct action of daidzein on basic ovarian cell functions and the ability of these cells to respond to FSH indicate the potential influence of soya‐containing diets on female reproductive processes via direct action on the ovary.  相似文献   
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133.
Thoracic radiography is an important diagnostic tool for feline respiratory medicine. The aim of this study was (1) to assess age-related changes of thoracic radiographic views in healthy young cats and (2) to test if experimentally-induced bronchial inflammation by inhaling Ascaris suum (AS) allergens leads to radiographic changes after single or repeated exposures. Healthy cats (n=15-30) aged between 6 and 30 months were evaluated. Eight healthy cats and eight AS-sensitised cats, respectively, inhaled sterile saline or allergen. Radiographs were taken 24h before, and 6, 24 and 48 h after the challenge. Bronchoalveolar lavage (BAL) was performed after the last radiographic examination. AS-sensitised cats underwent three further allergen challenges at 3-month intervals. The radiographic evaluation was based on a scoring system considering bronchial, interstitial and alveolar patterns. A significant age-related increase in interstitial and total radiographic score was detected in healthy cats older than 18 months and in healthy cats older than 24 months. Whilst saline inhalation did not affect radiographic scores, a single AS challenge induced significant changes of all scores within 6-24h. A significant positive correlation between radiographic scores and BAL neutrophils and eosinophils was found. Repeated AS challenges did not induce irreversible changes in radiographic scores.  相似文献   
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135.
  1. Artificial barriers on lowland rivers impede the spawning migrations of anadromous fishes, preventing access to historical spawning areas. In the cryptic European shads Alosa alosa and Alosa fallax (‘shad’ hereafter), this has resulted in population declines across their range. Conservation programmes aim to facilitate the passage of migrators over these barriers and so require baseline information on the spatial and temporal extent of current migrations.
  2. Here, a shad-specific environmental DNA (eDNA) assay was used to quantify the spatial extent of shad spawning migrations in the River Severn basin, western England. This basin is characterized by the presence of multiple barriers in the lower catchment. In 2017, the eDNA assay was piloted in the River Teme, an important shad spawning tributary, and then applied in 2018 and 2019 across the lower Severn basin.
  3. In all years, shad DNA was detected between mid-May and mid-June, with the maximum spatial extent of shad distribution being in early June when shad eDNA was detected upstream of weirs that were generally considered as impassable. In 2018, this included the detection of shad above the most upstream weir on the main River Severn that required individual fish to have passed six weirs.
  4. Although barriers inhibit the spawning migrations of shad, this eDNA assay showed that some highly vagile individuals might be able to ascend these barriers and migrate considerable distances upstream. This suggests that efforts to increase the permeability of these barriers could result in relatively high numbers of migrating shad reaching upstream spawning areas. These results demonstrate that this eDNA assay could also be used across their range, to further quantify the spatial extent of their spawning, including in highly fragmented rivers and those where shad are believed to spawn only occasionally and are rarely observed.
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136.
The aim of this work was to assess the potential use of different dried macroalgae as food in the rearing of Paracentrotus lividus. Growth, consumption and food conversions were compared in adult sea urchins fed with fresh or dried thalli of four macroalgae species. Six experimental diets were tested: (a) fresh Palmaria palmata; (b) fresh Saccharina latissima; (c) dry P. palmata; (d) dry S. latissima; (e) dry Laminaria digitata and (f) dry Grateloupia turuturu. Linear growth rates were similar for all treatments. Specific growth rate was higher in sea urchins fed with fresh P. palmata, but no difference was found between animals fed with fresh S. latissima and those fed with dried diets. Regarding daily food consumption (DFC), sea urchins consumed the same amount of dried macroalgae as fresh but exhibited a higher food conversion efficiency (FCE) when fed with fresh P. palmata. However, this FCE was only significantly higher when compared to sea urchins fed with dry L. digitata. Dried G. turuturu is not a suitable diet due to its rapid degradation after rehydration. The results suggest that P. lividus adults can be reared on dried macroalgae thalli without detriment to their somatic growth, especially over short periods. The low cost of feeding sea urchins with this diet could help small shellfish farmers to diversify their production into echinoculture.  相似文献   
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