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41.
将经直接消化的斑马鱼头肾细胞或经短暂培养的尾鳍细胞核移植到同种成熟具核卵子中 ,移核卵可发育到原肠晚期 ;将移核卵发育成的囊胚细胞核作供体进行第 2次核移植 ,受体卵可发育到尾芽期或肌肉感应期。流式细胞仪测定 DNA含量表明 ,受体卵发育形成的囊胚细胞 DNA含量与正常囊胚细胞 DNA含量相同 ,由此可知 ,移核卵中的雌原核没有参与移核胚胎的发育。 相似文献
42.
Estradiol, or 17-β-estradiol (E2), the most potent naturally occurring estrogen, is involved in the hormone-immune system interaction in both mammals and fish. However, in vivo studies are largely limited, and little is known about whether E2 exerts similar effects on both female and male zebrafish (Danio rerio). Here, we show exposure of both sexes of D. rerio to 20 nmol/L E2 resulted in a significant increase in Vg1 expression, but caused little damage to the hepatocytes, suggesting that this is the optimum E2 concentration. Also, exposure to 20 nmol/L E2 for 20 days caused a marked increase in plasma IgM levels, but had little influence on the peripheral leukocyte density, providing the first evidence of a hormone-immune system interaction in this species. 相似文献
43.
激素诱导欧氏六线鱼性腺发育的初步研究 总被引：3，自引：1，他引：2
随着鱼类成为人工养殖对象,人们越来越希望养殖鱼类能在人为控制下成熟和产卵,从而打破自然环境下的繁殖周期,为养殖生产提供更多的、适合生产需要的苗种,本研究采用LRH-a(促性腺释放激素类似物),17β-雌二醇及以生理盐水作为对照组,使用腹腔注射的方法,对欧氏六线鱼的性腺发育进行诱导实验,旨在探讨激素对鱼类性腺发育的影响。1 材料和方法1996年9～10月间,取网箱暂养的欧氏六线鱼39尾,随机取7尾以观察实验前六线鱼的性腺发育状况,逐尾称体重,解剖取出生殖腺和内脏,称量生殖腺重和净重,计算性腺指数,并求出其平均值,♀:0.64±0.10,♂:0.… 相似文献
44.
纤维蛋白溶解系统是凝血系统的重要组成部分,对于维持血液的流动性和血管的完整性起着至关重要的作用。作为纤溶系统中心组分的纤溶酶原在其激活剂的作用下转变为活性形式的纤溶酶,进而降解纤维蛋白原,并能溶解血栓。纤溶酶也参与金属蛋白酶类和脂氧合酶类激活作用,还与细胞许多迁移相关的生理和病理过程相关诸如癌症、血管增生、卵子成熟、胚胎发生、伤口愈合以及病原侵入相关。本文简要概述了纤溶酶原和纤溶酶的结构、功能及其进化的研究进展。 相似文献
45.
In this study, we isolated a polysaccharide from Branchiostoma belcheri (PBB) by enzymatic protein hydrolysis and alcohol precipitation. We investigated the effects of PBB supplementation on DNA
oxidation and growth of the transplanted tumor cells Sarcoma (S180) in mice. Sixty healthy Kunming mice weighing between 18 and 25 g were randomly assigned to 6 groups, each consisting of
10 animals. All the mice, except for the blank control group, were inoculated with S180 sarcoma cells into the axilla of the
left foreleg. PBB was given to mice by gavage at doses of 0 (model control), 25, 50, or 100 mg/kg b.w. in 0.2 ml saline for
30 days. The fifth group of S180-mice was given cytoxan (50 mg/kg) by peritoneal injection as a positive control group. The animals had free access to food
and water. The mice were sacrificed after the final treatment and blood was quickly collected. Spontaneous and oxidized DNA
damage of peripheral lymphocytes induced by H2O2 were analyzed by SCGE. O6-methyl-guanine (O6-MeG) was measured by high-performance capillary zone electrophoresis. The average tumor weights (0.856–1.118 g) of the three
PBB groups were significantly lower than that of the model control group (1.836 g) (p<0.05). The tumor inhibition ratios of the PBB groups were 39.1%–53.4% and similar to the cytoxan positive group (57.5%).
There were no significant differences in spontaneous DNA damage in peripheral lymphocytes among the groups. The oxidative
DNA damage induced by 10 μmol/L H2O2 in the 50 and 100 mg/kg b.w. groups were 246.1 AU and 221.7 AU, respectively, both of which were significantly lower than
that in the model group (289.0 AU; p<0.05). The plasma concentrations of O6-MeG in the 25, 50, and 100 mg/kg supplemented groups were 2.09 μmol/L, 1.86 μmol/L, and 1.63 μmol/L, respectively, all of
which were significantly lower than that of the model group (2.67 μmol/L; p<0.05). These results indicated that PBB may have antioxidative activity and thus reduce oxidation-induced DNA damage. 相似文献
46.
载脂蛋白D(ApoD)属于脂蛋白家族,目前对ApoD的研究集中在基因表达、组织分布和具体功能上,而对其包括调控区在内的基因组结构分析相对较少,而该部分内容对进一步了解和阐明ApoD蛋白功能有重要意义.本文从生物信息学角度对分属于原生动物、无脊椎动物、头索动物和脊椎动物类群的10种动物ApoD的基因结构及调控区的调控元件的分析及比较,发现:(1) ApoD基因结构从原生动物草履虫到原口动物再到后口动物海胆的进化过程中不保守,但在分析的几种脊椎动物中相当保守;(2) 文昌鱼ApoD基因扮演从无脊椎动物到脊椎动物承上启下的角色,代表脊椎动物ApoD基因原型;(3) 调控区大多数调控元件为不同动物共有,说明ApoD功能及其表达调控在进化中的保守性;(4) ApoD基因个别调控元件是随着物种进化而出现并开始发挥相关作用,如SF-1;还有个别的调控元件在进化过程中还没有发现其规律,这可能说明ApoD的某些功能因物种不同存在一定差异. 相似文献
47.
48.
The distribution and ultrastructure of pigment cells in skins of normal and albino adult turbots were examined with transmission electron microscopy (TEM). Three types of pigment cells of melanophore, iridophore and xanthophore have been recognized in adult turbot skins. The skin color depends mainly on the amount and distribution of melanophore and iridophore, as xanthophore is quite rare. No pigment cells can be found in the epidermis of the skins. In the pigmented ocular skin of the turbot, melanophore and iridophore are usually co-localized in the dermis. This is quite different from the distribution in larvae skin. In albino and white blind skins of adult turbots, however, only iridophore monolayer still exists, while the melanophore monolayer disappears. This cytological evidence explains why the albino adult turbot, unlike its larvae, could never resume its body color no matter what environmental and nutritional conditions were provided. Endocytosis is quite active in the cellular membrane of the iridophore. This might be related to the formation of reflective platelet and stability of the iridophore. 相似文献
49.
In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid (IMI) to the gill cell line of flounder (FG) that collected in the gill of Paralichthys olivaceus, was examined by 3 widely used endpoint bioassays: NR (neutral red), MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) and TCP (total cell protein). The result shows that the IMI increased at concentrations ≥0.5 μg/ml. The IC50 value of NR, MTT, and TCP was 41.86, 38.46, and 39.08 μg/ml, respectively. The ultrastructural observation revealed that the mitochondria of the cells exposed to 60 μg/ml IMI for 48 h were severely damaged, swollen or disrupted, while their nuclei and rough endoplasmic reticulum (RER) remained normal. This would suggest that the mitochondria are probably the primary target of IMI. 相似文献
50.
Evaluation of the damage in fish spermatozoa cryopreservation 总被引：4，自引：0，他引：4
Cryodamages occur during sperm cryopreservation. Cryopreservation of fish sperm usually results in marked decrease in sperm quality, such as swelling or disruption of the plasma membrane, mitochondrial dysfunction, diminished sperm motility, impaired velocity, shorter motility period, denaturation, and release of some enzymes from spermatozoa. In this paper, damages in morphology, physiology, biochemistry and metabolism, and genetic integrity of fish semen after cryopreservation are discussed. New approaches in assessment of fish thawed sperm quality such as computer assisted sperm analysis, flow cytometic analysis combined with fluorescent probes and single cell gel electrophoresis are also briefly reviewed. 相似文献