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101.
Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG1, but colostral IgM, IgG2, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG1, IgA and IgM concentrations in cows, but plasma IgG1 concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG1 concentrations in β‐carotene‐deficient cows.  相似文献   
102.
Ethylene biosynthesis in kiwifruit, Actinidia chinensis ‘Sanuki Gold’ was characterized using propylene, an ethylene analog, and 1-methylcyclopropene (1-MCP), an inhibitor of ethylene perception. In fruit harvested between a young stage (66 days after pollination) (DAP) and an early commercial harvesting stage (143 DAP), 2 days of exposure to propylene were sufficient to initiate ethylene biosynthesis while in fruit harvested at commercial harvesting stage (154 DAP), 4 days of propylene treatment were required. This observation suggests that response of ethylene biosynthesis to propylene treatment in kiwifruit declined with fruit maturity. Propylene treatment resulted in up-regulated expression of AC-ACO1, AC-ACO2, AC-SAM1 and AC-SAM2, prior to the induction of AC-ACS1 and ethylene production, confirming that AC-ACS1 is the rate limiting step in ethylene biosynthesis in kiwifruit. Treatment of fruit with more than 5 μL L?1 of 1-MCP after the induction of ethylene production subsequently suppressed ethylene production and expression of ethylene biosynthesis genes. Treatment of fruit with 1-MCP at harvest followed with propylene treatment delayed the induction of ethylene production and AC-ACS1 expression for 5 days. These observations suggest that in ripening kiwifruit, ethylene biosynthesis is regulated by positive feedback mechanism and that 1-MCP treatment at harvest effectively delays ethylene production by 5 days.  相似文献   
103.
Polymorphonuclear cells of the peripheral blood in the chicken significantly increased their phagocytosis when cultured with sugar cane extract (SCE; 250-1,000 microg/ml) for 24 hr. Chickens orally administered SCE (500 mg/kg/day) for 3 or 6 consecutive days at 1 week of age showed significantly higher body weight and gain in body weight/day and a lower food conversion ratio within the growing period of 6 weeks than physiological saline-administered control chickens. Furthermore, oral administration of SCE also resulted in significantly higher immune responses against sheep red blood cells and Brucella abortus. These results suggest that SCE has immunostimulating and growth promoting effects in chickens.  相似文献   
104.
We have previously established the method for isolation of ceramide aminoethylphosphonate (CAEP) from jumbo flying squid Dosidicus gigas. In this study, we performed a MTT assay to evaluate the safety of CAEP to the cell lines for the application to health food and supplements. The CAEP did not show any cytotoxicity to various HEK293-transfectant cells. Next, we elucidated the positive function of CAEP to the somatic cells. Recently, we have reported that hepatotoxin microcystin-LR was taken up into the hepatocytes mediated by hepatocellular uptake transporters OATP1B1 and OATP1B3, and the cells were induced cytotoxicity subsequently. Cytotoxicity of microcystin-LR to permanently OATP1B3-expressing HEK293-OATP1B3 cells rather than to HEK293-OATP1B1 cells was preferentially attenuated by CAEP in a concentration-dependent manner. In addition, the enzyme activity of serine/threonine phosphatase, which was inhibited by microcystin-LR, was recuperated by co-exposure to CAEP. Furthermore, microcystin-LR-induced cellular protein phosphorylation were disrupted by CAEP exposure. These results suggested that CAEP is a promising remedy and/or preventive medicine for liver damage with microcystin-LR.  相似文献   
105.
Dendritic cells (DCs) are professional antigen presenting cells, which initiate primary immune responses and also play an important role in the generation of peripheral tolerance. There is no reliable method established for the isolation of bovine peripheral blood DCs, and furthermore, the phenotypes and the functions of bovine DCs are still not fully clear. In the present study, we have attempted to identify bovine peripheral blood DCs by negative-selection. In bovine peripheral blood mononuclear cells (PBMC), we have newly characterized the phenotype of DCs, which is CD11c+/CD172a+. These cells display features of myeloid type DCs. In the thymic medulla, CD11c+/CD172a+ cells were also present and CD1+/CD172a+ cells were additionally detected as a population of DCs. The data suggest that one of the bovine DCs phenotypes from PBMC is derived from myeloid lineages lacking a CD1 molecule, which then drift to several tissues, and that they then may express a CD1 molecule upon their functional differentiation.  相似文献   
106.
Twenty‐four archival tags were recovered from Pacific bluefin tuna previously released off Tsushima Island in the East China Sea. By analysis of the time‐series data of the pressure and the ambient and internal temperature from the 24 tags, we examined the relationship between the tuna's pattern of diving and the thermocline depth. In the East China Sea, diving and feeding events occurred throughout almost the entire day in both winter and summer, suggesting that the purpose of diving is for feeding. In summer, the feeding frequency was greater than that in winter, which corresponds to the fact that growth is more rapid in summer than in winter. During summer in the Kuroshio–Oyashio transition region, on the other hand, feeding events were much more frequent than those in the East China Sea, in spite of a lower diving frequency. The mean horizontal distance traveled was also significantly higher and it seems that in this area they may move horizontally to feed on prey accumulated at the surface. We conclude that, in addition to the ambient temperature structure, the vertical and horizontal distribution of prey species plays an important role in the feeding behavior of Pacific bluefin tuna. One bluefin tuna migrated to the Oyashio frontal area, where both the horizontal and the vertical thermal gradients are much steeper. The fish spent most of the time on the warmer side of the front and often traveled horizontally to the colder side during the day, perhaps to feed. This implies that there is a thermal barrier effect, in this case from the Oyashio front, on their behavior. The frequency of feeding events was low, although all the monitored fish dived every dawn and dusk, irrespective of the seasons or location. It is possible that these twice‐daily diving patterns occurred in response to the change in ambient light at sunrise and sunset.  相似文献   
107.
108.
Since the first somatic cell cloned calves were born in Japan in 1998, more than 500 cloned cattle have been produced by somatic cell nuclear transfer and many studies concerning cloned cattle and their offspring have been conducted in this country. However, most of the results have been published in Japanese; thus, the data produced in this country is not well utilized by researchers throughout the world. This article reviews the 65 reports produced by Japanese researchers (62 written in Japanese and 3 written in English), which employed 171 clones and 32 offspring, and categorizes them according to the following 7 categories: (1) genetic similarities and muzzle prints, (2) hematology and clinical chemistry findings, (3) pathology, (4) growth performance, (5) reproductive performance, (6) meat production performance and (7) milk production performance. No remarkable differences in health status or reproductive performance were found among conventionally bred cattle, somatic cell cloned cattle surviving to adulthood and offspring of somatic cell cloned cattle. Similarities in growth performance and meat quality were observed between nuclear donor cattle and their clones. The growth curves of the offspring resembled those of their full siblings.  相似文献   
109.
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