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21.
Mitochondria are highly dynamic organelles that undergo constant fusion/fission as well as activities orchestrated by large dynamin-related GTPases. These dynamic mitochondrial processes influence mitochondrial morphology, size and function. Therefore, this study was conducted to evaluate the effects of mitochondrial fission inhibitor, mdivi-1, on developmental competence and mitochondrial function of porcine embryos and primary cells. Presumptive porcine embryos were cultured in PZM-3 medium supplemented with mdivi-1 (0, 10 and 50 μM) for 6 days. Porcine fibroblast cells were cultured in growth medium with mdivi-1 (0 and 50 μM) for 2 days. Our results showed that the rate of blastocyst production and cell growth in the mdivi-1 (50 μM) treated group was lower than that of the control group (P < 0.05). Moreover, loss of mitochondrial membrane potential in the mdivi-1 (50 μM) treated group was increased relative to the control group (P < 0.05). Subsequent evaluation revealed that the intracellular levels of reactive oxygen species (ROS) and the apoptotic index were increased by mdivi-1 (50 μM) treatment (P < 0.05). Finally, the expression of mitochondrial fission-related protein (Drp 1) was lower in the embryos and cells in the mdivi-1-treated group than the control group. Taken together, these results indicate that mdivi-1 treatment may inhibit developmental competence and mitochondrial function in porcine embryos and primary cells.  相似文献   
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为实现小麦赤霉病瘪粒快速识别,本研究使用主成分分析(Principal component analysis,PCA)结合最大类间方差法(Otsu)对小麦高光谱图像进行背景分割,以赤霉病瘪粒识别正确率为评价指标,探究判别分析方法与竞争性自适应权重取样法(Competitive adaptive reweighted sampling,CARS)的最佳组合方式.结果显示,基于全谱段构建的偏最小二乘判别分析(Partial least squares discrimination analysis,PLS-DA)和支持向量机判别分析(Sup-port vector machine discriminant analysis,SVM-DA)模型预测精度相同,外部验证集健康籽粒和赤霉病瘪粒识别正确率分别为95.2%和100.0%;基于CARS筛选的8个特征波长构建的CARS-PLS-DA模型外部验证集健康籽粒和赤霉病瘪粒识别正确率均为100.0%,预测精度高于CARS-SVM-DA模型,可有效实现赤霉病瘪粒的快速识别.研究结果将为谷物仓储和加工过程中赤霉病瘪粒高通量快速识别提供理论依据和技术支撑.  相似文献   
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Bovine somatic cell nuclear transfer (SCNT) is an important and powerful tool for basic research and biomedical and agricultural applications, however, the efficiency of SCNT has remained extremely low. In this study, we investigated the effects of cathepsin B inhibitor (E-64) supplementation of culture medium on in vitro development of bovine SCNT embryos. We initially used three concentrations of E-64 (0.1, 0.5, 1.0 μm), among which 0.5 μm resulted in the highest rate of blastocysts production after in vitro fertilization (IVF), and was therefore used for further experiments. Blastocyst development of SCNT embryos in the E-64 treatment group also increased relative to the control. Moreover, the cryosurvival rates of IVF and SCNT blastocysts were increased in E-64 treatment groups when compared with the control. On the other hand, we found that IVF and SCNT blastocysts derived from E-64-treated groups had increased total cell numbers and decreased apoptotic nuclei. Furthermore, assessment of the expression of apoptosis-related genes (Bax and Bcl-xL) in bovine IVF and SCNT blastocysts treated with E-64 by real-time RT-PCR analysis revealed suppressed expression of the pro-apoptotic gene Bax and stimulated expression of the anti-apoptotic gene Bcl-xL. Taken together, these finding indicate that addition of E-64 to embryo culture medium may have important implications for improving developmental competence and preimplantation quality in bovine IVF and SCNT embryos.  相似文献   
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Impact of the 1999 earthquake on mountain stream fishes in Taiwan   总被引:1,自引:0,他引:1  
LEE-SHING  FANG  I-SHIUNG  CHEN  KWEE SIONG  TEW  CHIAO-CHUAN  HAN  TSAI-FU  LEE  I-MING  CHEN 《Fisheries Science》2002,68(2):446-448
  相似文献   
28.
台湾雨量站的密度高居全世界前3名,然而雨量站往往由于设站时间不一致,或因天灾人祸而导致数据遗失;因此各水文观测站之降雨数据具模糊特性。降雨事件的特性,大致可区分为3个重要因子;降雨量、降雨时间及形状因子。常用之统计值为总降雨量、平均降雨量、最大降雨量、最小降雨量、中值降雨量、降雨延时、尖峰达到时间、偏态指标及峰态指标等9个物理量。研究以统计量及模糊理论为基础,分析屏东县气象局1992-2007年31个雨量站之总降雨量大于100mm,降雨延时3h以上之降雨事件(1177场)。研究结果显示:屏东县大于100mm之降雨,具长延时、高狭峰之特性;就气象站而言,气象站C0R38之暴雨事件,最接近整体降雨特性。  相似文献   
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A 9-month-old bitch was presented with respiratory distress 7 days after a road traffic accident. Radiographs showed a severe hydrothorax and moderate ascites. The removal of bile-stained fluid by thoracentesis reduced the dyspnoea. A diaphragmatic and a hepatic duct rupture were found and repaired at laparotomy. A biliary peritonitis and pleuritis was present. A blood bilirubin of 67 μmol/1 and elevated serum enzymes were present prior to surgery. These changes were largely reversed once the leakage was stopped.  相似文献   
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A diagnosis of dicoumarol toxicity in a herd of Friesian cattle was made following investigation of the deaths of three mature cows and eleven yearling heifers. Affected stock had been fed wrapped, bailed silage containing approximately 90% sweet vernal grass ( Anthoxanthum odoratum ). Sweet vernal grass contains coumarin, which can be converted to dicoumarol, a vitamin K antagonist, through the action of moulds. Most deaths were preceded by lethargy, severe anaemia and subcutaneous and internal haemorrhage. Dicoumarol toxicosis was suspected based on clinical signs, necropsy findings and prolonged prothrombin and activated partial thromboplastin times. Dicoumarol analysis of blood from affected animals and silage confirmed the diagnosis.  相似文献   
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