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51.
Atrioventricular valve dysplasia in Dalmatians   总被引:1,自引:0,他引:1  
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The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non‐breeding season in camel ovaries. A total of 21 mature, non‐pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3–5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin‐embedded ovarian tissues was performed to detect the localization of S‐100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S‐100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis.  相似文献   
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Drainage of peatlands affects the fluxes of greenhouse gases (GHGs). Organic soils used for agriculture contribute a large proportion of anthropogenic GHG emissions, and on-farm mitigation options are important. This field study investigated whether choice of a cropping system can be used to mitigate emissions of N2O and influence CH4 fluxes from cultivated organic and carbon-rich soils during the growing season. Ten different sites in southern Sweden representing peat soils, peaty marl and gyttja clay, with a range of different soil properties, were used for on-site measurements of N2O and CH4 fluxes. The fluxes during the growing season from soils under two different crops grown in the same field and same environmental conditions were monitored. Crop intensities varied from grasslands to intensive potato cultivation. The results showed no difference in median seasonal N2O emissions between the two crops compared. Median seasonal emissions ranged from 0 to 919?µg?N2O?m?2?h?1, with peaks on individual sampling occasions of up to 3317?µg?N2O?m?2?h?1. Nitrous oxide emissions differed widely between sites, indicating that soil properties are a regulating factor. However, pH was the only soil factor that correlated with N2O emissions (negative exponential correlation). The type of crop grown on the soil did not influence CH4 fluxes. Median seasonal CH4 flux from the different sites ranged from uptake of 36?µg CH4?m?2?h?1 to release of 4.5?µg?CH4?m?2?h?1. From our results, it was concluded that farmers cannot mitigate N2O emissions during the growing season or influence CH4 fluxes by changing the cropping system in the field.  相似文献   
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The share of organic dairy production in EU is increasing and this study describes the herd structure and cow performance in organic and conventional dairy production systems in Sweden. The data included records from 2 902 718 lactations, collected in organic (n = 471) and conventional (n = 13 976) herds between 1998 and 2005. Compared with conventional herds, the organic herds were larger and increased more rapidly in size. The replacement rate was slightly lower in organic herds and fewer Swedish Holsteins were used. The statistical analysis of cow performance in the first three lactations showed lower milk, fat and protein production in organic herds, but the increase in production from first to second lactation was larger when expressed in kg milk. Fertility was better for organically managed cows compared to conventionally managed cows, but the somatic cell count (SCC) was higher. However, at a given production level the fertility was slightly worse in organic herds while there was no difference in SCC. No interactions of importance were found between production system and breed for any trait.The results showed that organic and conventional dairy production differed regarding herd structure and cow performance. However, the differences in fertility and SCC found were to a high extent explained by the lower milk yield in organic production and no breed was found to perform better in either system.  相似文献   
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A 7-years-old Clydesdale mare was presented with severe abdominal distension and acute colic. Dilated large intestine was palpated per rectum and a ventral midline exploratory laparotomy was performed. A 180 degrees volvulus of the pelvic flexure was present, associated with an inelastic band of tissue connecting the mesocolon to the umbilicus. The band was ligated and transected, and the volvulus reduced. Postoperative complications included hyponatraemia, metabolic acidosis and laminitis. The possible aetiology of the mesocolic-umbilical band is discussed.  相似文献   
60.
CD8+ T cell cross-priming via transfer of proteasome substrates   总被引:1,自引:0,他引:1  
"Cross-priming" describes the activation of na?ve CD8+ T cells by professional antigen-presenting cells that have acquired viral or tumor antigens from "donor" cells. Antigen transfer is believed to be mediated by donor cell-derived molecular chaperones bearing short peptide ligands generated by proteasome degradation of protein antigens. We show here that cross-priming is based on the transfer of proteasome substrates rather than peptides. These findings are potentially important for the rational design of vaccines that elicit CD8+ T cell responses.  相似文献   
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