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51.
研究了乌苏里鸣螽的生物学特性。该虫在河北省秦皇岛市 1年发生 1代 ,以滞育卵在土内越冬 ,翌年 3月下旬~ 6月上旬孵化为若虫。若虫共 7龄 ,1龄期 1 3~ 2 9d ,2龄期 8~ 2 0d ,3龄期 7~ 1 3d ,4龄期 6~ 9d,5龄期 6~ 9d ,6龄期 5~ 1 5d ,7龄期 1 2~ 1 7d。 6月下旬~ 8月中旬羽化为成虫 ,雌成虫产卵自 7月上旬至 9月下旬结束。成虫平均寿命 81 2 5d。  相似文献   
52.
Neuronal apoptosis mediated by the mitochondrial apoptosis pathway is an important pathological process in cerebral ischemia–reperfusion injury. 14,15-EET, an intermediate metabolite of arachidonic acid, can promote cell survival during ischemia/reperfusion. However, whether the mitochondrial apoptotic pathway is involved this survival mechanism is not fully understood. In this study, we observed that infarct size in ischemia–reperfusion injury was reduced in sEH gene knockout mice. In addition, Caspase 3 activation, cytochrome C release and AIF nuclear translocation were also inhibited. In this study, 14,15-EET pretreatment reduced neuronal apoptosis in the oxygen–glucose deprivation and re-oxygenation group in vitro. The mitochondrial apoptosis pathway was also inhibited, as evidenced by AIF translocation from the mitochondria to nucleus and the reduction in the expressions of cleaved-caspase 3 and cytochrome C in the cytoplasm. 14,15-EET could reduce neuronal apoptosis through upregulation of the ratio of Bcl-2 (anti-apoptotic protein) to Bax (apoptosis protein) and inhibition of Bax aggregation onto mitochondria. PI3K/AKT pathway is also probably involved in the reduction of neuronal apoptosis by EET. Our study suggests that 14,15-EET could suppress neuronal apoptosis and reduce infarct volume through the mitochondrial apoptotic pathway. Furthermore, the PI3K/AKT pathway also appears to be involved in the neuroprotection against ischemia–reperfusion by 14,15-EET.  相似文献   
53.
视觉通路的研究在神经科学、 仿生应用和医学治疗上都具有十分重要的意义。西方蜜蜂Apis mellifera作为神经生物学研究的重要模式生物已被广泛地应用于视觉通路的研究。蜜蜂的视觉器官包括1对复眼和3只单眼, 复眼是形成视觉的主要感觉器官。视叶是蜜蜂传递和处理视觉信息的主要神经构造, 它包括视神经节层、 视髓质层、 视小叶和前视结节4个等级的神经纤维网。复杂的视觉信息在经过大脑的各级神经时被分离, 以许多空间隔离的并行连续的视觉通路传递和加工, 然后汇集到高级脑中枢, 部分甚至与其他感觉模态的信息相整合, 最终输出有效信息来调控蜜蜂的各种行为。本文按照信息在视叶中逐级传递的顺序对蜜蜂复眼的视觉通路研究进展进行综述。  相似文献   
54.
High temperature will cause animal tissues or cells damage. Rosmarinic acid (RA) is a good antioxidant and health care product, but the roles of RA in muscle cells damage and the mechanisms which caused by high temperature is still unknown. In this study, the roles of RA on hyperthermia-induced apoptosis and damage of C2C12 muscle cells were investigated. C2C12 cells were cultured in medium with different concentration (0, 25, 50, 100 µM) RA and treated in 42 °C high temperature to induce cellular apoptosis and damage. Then, these cells were analyzed effect of different dose of RA on cells apoptosis and damage. The results indicated that RA has protective effect on heat-stress induced cellular damage, and the cells have the higher cell viability at the dose of 50 µM RA by MTT assay. Hochest33342/PI double staining showed that the cellular apoptosis of C2C12 cells were decreased in the presence of selected 50 µM RA. Malondialdehyde formation and reactive oxygen species levels were also decreased significantly, but cellular superoxide dismutase activity was increased significantly in the presence of RA even in the condition of 42 °C. Meanwhile, Caspase-3 mRNA expression, Caspase-3 activity, and Bax/Bcl-2 ratio were reduced significantly, but the mRNA expression of Hsp72 was increased significantly in those hyperthermia-induced C2C12 cells in the presence of 50 µM RA. Taken together, the results at least discovered that RA has protective effects on hyperthermia-induced cellular apoptosis and damage of muscle cells by change the expression of stress-genes and increasing intracellular antioxidant capability.  相似文献   
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56.
长春花悬浮细胞培养体系对脱氢表雄酮的生物转化   总被引:1,自引:0,他引:1  
利用长春花(Catharanthus roseus (L.) G. Don)悬浮细胞培养体系对脱氢表雄酮进行了生物转化,通过柱层析及制备薄层层析进行分离纯化,并利用核磁共振氢谱、碳谱以及ESI等仪器分析手段进行了化合物的结构鉴定, 分离到13个转化产物,并对其中的9个进行了结构鉴定,它们分别是:androst-4-ene-3,17-dione (Ⅰ)、 6a-hydroxyandrost-4-ene-3,17-dione (Ⅱ)、 6a,17b-dihydroxyandrost-4-en-3-one (Ⅲ)、 6b-hydroxyandrost-4-ene-3,17-dione(Ⅳ)、 17b-hydroxyandrost-4-en-3-one (Ⅴ)、 15a, 17b-dihydroxyandrost-4-en-3-one (Ⅵ), 15b,17b-dihydroxyandrost-4-en-3-one (Ⅶ)、 14a-hydroxyandrost-4-ene-3,17-dione (Ⅷ)和17b-hydroxyandrost-4-ene-3,16-dione (Ⅸ)。所鉴定的9个化合物均为首次通过生物转化的方法从长春花悬浮细胞培养体系中分离得到。  相似文献   
57.
采用PAGE和SDS-PAGE以及Western blot 的方法,分析了粘虫Mythimna separata幼虫、蛹及成虫体内的储存蛋白。结果表明,粘虫体内存在两种储存蛋白,其中一种为SP-1,即幼虫特异性储存蛋白,从6龄粘虫幼虫的2日龄开始出现在血淋巴中,到末日龄时达到峰值,停止取食后从血淋巴中消失;另一种为SP-3,在化蛹时开始出现在脂肪体中,一直到成虫期仍可持续表达,因此属于持续性储存蛋白。SP-1为分子量约94 kD和100 kD的2种亚基组成的蛋白质,而SP-3为分子量约94 kD的1种亚基组成的蛋白质。SP-1含8.16%的芳香类氨基酸,3.06%的甲硫氨酸。经苦皮藤素Ⅴ亚致死剂量处理5龄粘虫幼虫后的6龄2、3、4日龄粘虫幼虫体内储存蛋白的含量明显低于对照组,对5日龄后粘虫处理组和对照组体内储存蛋白的含量及雌性成虫产卵量没有明显影响。  相似文献   
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59.
Neoascarophis sinensis n. sp. collected from the whitespotted conger Conger myriaster (Brevoort) (Anguilliformes: Congridae) in the Yellow and East China Seas, is described using both light and scanning electron microscopy. The new species is characterised mainly by the body size (8.5–10.5 mm in the males, 9.5–14.0 mm in the females), the location of the vulva (near equatorial region of the body), the non-bifurcate deirids, the lengths of the vestibule (40–50 µm in the males, 30–60 µm in the females) and glandular oesophagus (2.5–3.1 mm in the males, 3.1–3.5 mm in the females) and the morphology and length of the spicules (left spicule 400–410 µm, right spicule 130–150 µm). Neoascarophis sinensis n. sp. is the first species of Neoascarophis Machida, 1976 reported from the anguilliform fish and is also the only species of this genus found in the Chinese waters.  相似文献   
60.
从驯化后的活性污泥中筛分、诱变出一株性能较好的异养硝化菌JZ1-1.经形态及生理生化特性分析,鉴定菌株JZ1-1为胶样菌属(Colloides sp.).分别考察了碳源、C/N、pH、溶解氧、温度和铵态氮初始浓度对JZ1-1硝化性能的影响.结果表明:菌株对柠檬酸钠的利用较好;C/N为10 ~14、30℃、pH 6-9和转速150 r·min-1以上有利于铵态氮的降解;菌株对中高浓度铵态氮废水(100 mg·L-1≤铵态氮浓度≤500 mg·L-1)的降解效果显著.经5次继代培养,菌株的稳定性较好.  相似文献   
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