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排序方式: 共有689条查询结果,搜索用时 171 毫秒
681.
G Sconzo M C Roccheri M La Rosa D Oliva A Abrignani G Giudice 《Cell differentiation》1986,19(3):173-177
Preheating at 31 degrees C induces thermotolerance in Paracentrotus lividus embryos, which therefore become able to withstand 1-h treatment at the otherwise lethal temperature of 35 degrees C, and to develop normally. The acquisition of thermotolerance is positively correlated with the amount of heat shock proteins produced during the 31 degrees C treatment. Evidence is provided that the heat shock proteins, although present in the embryo for long periods after synthesis, lose their effect on thermotolerance within 3 h of the cessation of synthesis. 相似文献
682.
The aim of this study was to assess plasma biochemistry parameters with the potential of being used as indicators of the nutritional status for healthy gilthead seabream juveniles. Triplicate groups of 18 seabream (body weight of 58 g) were kept unfed for 24 h, 7 or 14 days. Nine fish per treatment were then sampled randomly for blood collection and the following parameters analyzed in the plasma using standard clinical methods: glucose; protein; triglycerides; cholesterol; calcium; magnesium; inorganic phosphorus; alkaline phosphatase (ALP); aspartate aminotransferase (AST); lactate dehydrogenase (LDH); gamma‐glutamyl transferase (GGT); creatine phosphokinase (CPK); and lipase. Biochemical parameters showed lower variability among individuals than did enzymatic parameters. Plasma glucose, protein, cholesterol, calcium and inorganic phosphorus levels were inversely related to the duration of starvation. On the contrary, plasma triglycerides decreased significantly during the first week of starvation and remained stable in the second week. Plasma ALP, AST and LDH decreased significantly after 1 week of starvation and then remained constant. In healthy seabream juveniles, plasma glucose, protein, cholesterol, calcium and inorganic phosphorus are responsive to starvation and may be useful indicators of the nutritional status of the animals. Indicative baseline reference values for gilthead seabream juveniles starved for 24 h and held at optimum temperature are: protein, 3.7–4.9 g dl?1; cholesterol, 341–407 mg dl?1; calcium, 13.1–8.0 mg dl?1; and inorganic phosphorus, 10–14.2 mg dl?1. Plasma triglycerides, along with plasma enzyme activities, may be useful as indicators of short term starvation. For these parameters baseline values after 1 week of starvation were: triglycerides: 138–230 mg dl?1; ALP: 58–125 U L?1; AST: 15–127 U L?1; and LDH 61–677 U L?1. Plasma glucose is only responsive to longer starvation periods, remaining relatively stable during the first week of starvation, and ranging from 59 to 196 mg dl?1. 相似文献
683.
Jun Li Fawzia Bardag-Gorce Joan Oliva Jennifer Dedes Barbara A. French Samuel W. French 《Genes & nutrition》2010,5(2):169-179
Chronic ethanol ingestion, achieved by feeding ethanol at a constant rate using intragastric tube feeding, alters the expression of genes in the liver. This is done by epigenetic mechanisms, which depend on the blood alcohol levels at the time of killing. However, acute bolus feeding of ethanol changes gene expression without lasting epigenetic changes. This occurs with histone 3 methylation and acetylation modifications. The gene expression response to an acute bolus of ethanol might be modified by feeding S-adenosylmethionine (SAMe), a methyl donor. In the present study, rats were given a bolus of ethanol (6 g/kg body weight (bw), SAMe (1 g/kg bw), ethanol + SAMe, or isocaloric glucose. The group of rats (n = 3) were killed at 3 and 12 h post bolus, and gene microarray analysis was performed on their liver cells. SAMe reduced the 3 h blood ethanol levels and increased the ALT levels at 3 h. Venn diagrams showed that alcohol changed the expression of 646 genes at 3 h post bolus and 586 genes at 12 h. SAMe changed the expression of 1,012 genes when fed with ethanol 3 h post ethanol bolus and 554 genes at 12 h post ethanol bolus. SAMe alone changed the expression of 1,751 genes at 3 h and 1,398 at 12 h. There were more changes in gene expression at 3 h than at 12 h post ethanol when ethanol alone was compared to the dextrose control. The same was true when SAMe was compared to SAMe + ethanol. Ethanol up regulated gene expression in most functional pathways at 3 h. However, when SAMe was fed with ethanol at 3 h, most pathways were down regulated. At 12 h, however, when ethanol was fed, the pathways were half up regulated and half down regulated. The same was true when SAMe + ethanol was fed. The expression of epigenetically important genes, such as BHMT and Foxn3, was up regulated 3 h post alcohol bolus. At 3 h, SAMe down regulated the expression of genes, such as BHMT, Mat2a, Jun, Tnfrs9, Ahcy 1, Tgfbr1 and 2, and Pcaf. At 12 h, the insulin signaling pathways were half down regulated by ethanol, which was partly prevented by SAMe. The MAPK pathway was up regulated by ethanol, but SAMe did not prevent this. In conclusion, profound changes in gene expression evolved between 3 h and 12 post ethanol bolus. SAMe down regulated these changes in gene expression at 3 h, and less so at 12 h. 相似文献
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685.
dos Santos Jorge Sousa Karolyne Parisi Júlia Risso de Souza Amanda Cruz Matheus de Almeida Erbereli Rogério de Araújo Silva Jonas do Espirito Santo Giovanna do Amaral Gustavo Oliva Martignago Cintia Cristina Santi Fortulan Carlos Alberto Granito Renata Neves Renno Ana Claudia Muniz 《Marine biotechnology (New York, N.Y.)》2023,25(2):259-271
Marine Biotechnology - The inorganic part of marine sponges, called Biosilica (BS), presents an osteogenic potential and the ability of consolidating fractures. Moreover, 3D printing technique is... 相似文献
686.
M. Meneses M.D. Megías J. Madrid A. Martínez-Teruel F. Hernndez J. Oliva 《Small Ruminant Research》2007,70(2-3):292-296
The crude by-product left after industrial processing of artichoke (Cynara scolymus L.) was ensiled in microsilos and sampled at different times. To evaluate its suitability as animal feed, various fermentative, chemical and phytosanitary parameters were determined. The by-product showed a good aptitude for ensilage, having a pleasant smell and good visual characteristics. The DM content was 297 g kg−1, and no effluents were detected. It stabilized after 12 days of ensiling and showed a pH value of 4.1 at the end of the process. Only small losses were detected in its chemical value after the ensiling period. Prometryn was the only phytosanitary product found at day 0 (0.04 ppm a concentration below the maximum amount permitted by law), but was not detected after 12 days of ensilage. It is concluded that the silage by-product can be used as animal feed. 相似文献
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