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81.
共培养对延边黄牛重组胚体外发育的影响   总被引:1,自引:1,他引:0  
以新鲜的颗粒细胞作为供核细胞,以延边黄牛MⅡ期去核的卵母细胞作为受体进行体外培养.使用CR1aa培养液培养时卵裂率(83.7%)显著高于TCM-199液和mSOF液组(76.9%和77.4%),但在重组胚的早期发育各阶段都不存在统计学差异(p>0.05).以CR1aa和TCM-199为基础液时,输卵管上皮细胞和颗粒细胞共培养在卵裂率及重组胚的各阶段发育率都有显著提高(p<0.05).结果表明:CR1aa培养液适用于延边黄牛重组胚的体外培养,以CR1aa液 输卵管上皮细胞和TCM-199液 颗粒细胞共培养的形式效果更好(p<0.05).  相似文献   
82.
【目的】探讨输卵管上皮细胞和基质细胞的体外分离培养方法及在激素刺激下基质细胞对上皮细胞的作用。【方法】通过差速贴壁法体外分离纯化兔输卵管上皮细胞和基质细胞;免疫组织化学染色和免疫荧光染色方法鉴定上皮细胞和基质细胞的类型和纯度;并在无胎牛血清的DMEM/F12培养液和含体积分数15%胎牛血清的DMEM/F12培养液中,分别添加不同浓度的雌激素(17β-E2)和孕激素(P4),比较上皮细胞和基质细胞的增殖情况及其对上皮细胞/基质细胞共培养的影响。【结果】体外成功地分离到兔输卵管上皮细胞和基质细胞;兔输卵管上皮细胞经鼠抗人细胞角蛋白单克降抗体(anti-CK18)免疫组织化学染色后呈阳性,细胞质呈棕色,免疫荧光染色检测其纯度在98%以上;兔输卵管基质细胞经鼠抗人波形蛋白单克降抗体(anti-Vimentin)免疫组织化学染色后呈阳性,细胞质呈棕色,免疫荧光染色检测其纯度在95%以上。17β-E2和P4均能促进兔输卵管上皮细胞和基质细胞的增殖,使其数量明显增加。基质细胞与上皮细胞共培养,上皮细胞增殖较快。【结论】差速贴壁法能够获得纯度较高的输卵管上皮细胞和基质细胞,在17β-E2和P4共同作用下,少量基质细胞能促进上皮细胞生长。  相似文献   
83.
以作物[粳稻(Oryza sativa L.subsp.japonica Kato)、籼稻(Oryza sativa L.subsp.sativa)、小白菜(Brassica rapa L.ssp.pekinensis)和空心菜(Ipomoea aquatic Forsk)]-黄颡鱼(Pelteobagrus fulvidraco)共作为例,探索不同类型作物与鱼共作对养殖水体N2O产生和排放的影响。利用静态箱和顶空平衡-气相色谱法,测量水稻/蔬菜-黄颡鱼共作系统N2O排放通量和上覆水与土壤孔隙水N2O浓度。不同作物-鱼共作对养殖水体N2O排放均有显著消减作用。与单养鱼处理相比,籼稻-鱼共作、粳稻-鱼共作、空心菜-鱼共作和小白菜-鱼共作处理N2O排放量分别减少82.1%、69.2%、67.9%和60.3%。稻-鱼共作可以同时减少上覆水和土壤孔隙水中N2O浓度,但菜-鱼共作仅减少上覆水中N2O浓度。稻-鱼共作显著降低养殖水体TN、NH4+-N、NO3--N和底泥NH4+-N、DON浓度,菜-鱼共作仅显著降低养殖水体NO3--N浓度。作物-鱼共作处理显著增加养殖前期底泥中nirK和nosZ基因丰度,对nirS基因丰度没有显著影响。作物-鱼共作处理对鱼产量没有显著影响,但是获得额外的作物产品,显著提高了系统氮素养分利用率。与单养鱼相比,水稻和蔬菜与鱼共作均能显著减少N2O排放,提高养殖系统氮素利用率。籼稻-鱼共作的减排效应要优于其他3种共作处理。  相似文献   
84.
高海拔稻田养鱼与常规粳稻新品种选择试验探索   总被引:1,自引:0,他引:1  
在以往试验的基础上,结合稻田养鱼的成功经验,通过不断完善试验方案,在高海拔养鱼稻田开展了粳稻新品种选择试验。结果为,养鱼稻田新品种比较试验田稻谷产量575.1 kg/667 m^2,鱼产量40.6 kg/667 m^2,周边非养鱼稻田稻谷产量645.2 kg/667 m^2,试验田稻谷价高,养鱼增收1497.3元/667 m^2。  相似文献   
85.
Fowl typhoid and pullorum disease, caused bySalmonella enterica serovars Gallinarum biovarsSalmonella Gallinarum (S. Gallinarum) andSalmonella Pullorum (S. Pullorum), remain large threat to the organic poultry industry. These infections are serious threats to poultry health and overall flock viability especially at their early age. These avian pathogens cause a significant production loss and price increase of poultry products especially organic poultry products due to lack of antibiotics use. As a result, alternative intervention strategies have become an urgent demand of the farmers. Natural antimicrobials from plant products, such as bioactive compounds from berry juice byproducts can play important role in such a situation. In this study, we showed that blackberry and blueberry pomace extracts inhibitedS. Gallinarum andS. Pullorum growth in vitro. Two mg gallic acid equivalent (GAE)/mL blackberry or blueberry pomace extract reduced the growth of both pathogens by more than 5 logs at 24 h in broth. In semisolid poultry fecal medium, which contains poultry gut nutrients available to the gut bacteria, 1.0 mg GAE/mL of both extracts reduced the growth of these pathogens by more than 2 logs at 24, 48, and 72-h time points.S. Gallinarum andS. Pullorum were completely inhibited by 1.0 mg GAE/mL both extracts in water. The growth of probioticLactobacillus plantarum (L. plantarum) was unaffected in the presence of berry pomace extracts in broth but growth stimulation was observed in fecal medium when grown in presence of these extracts at 72 h. Moreover,L. plantarum completely inhibitedS. Gallinarum andS. Pullorum when co-cultured in fecal medium in the presence of 1.0 mg GAE/mL of both pomace extracts. In this study, we conclude that bioactive extracts from berry pomace are potential antimicrobials for organic producers which will modulate poultry gut microflora and improve productivity, product safety, and quality.  相似文献   
86.
共培养系统的体细胞类型和状态对猪胚胎早期发育的影响   总被引:6,自引:0,他引:6  
经体外成熟、受精和培养获得猪胚胎 ,采用体细胞共培养研究了体细胞类型和状态对胚胎早期发育的影响。取体外成熟的不同直径卵泡 (>5 m m,2~ 5 mm)卵母细胞的卵丘团 (颗粒细胞团 ) ,培养铺层后与猪受精卵共培养 ,组间受精卵的卵裂率和发育能力无显著差异 ;根据卵巢的状况对猪输卵管上皮细胞 (POECs)的状态进行分组 ,受精卵和卵巢表面布满卵泡的 POECs共培养 ,卵裂率显著低于卵巢表面有黄体和 /或红体的 POECs共培养组 (P<0 .0 5 ) ,虽然各组间 3~ 4-细胞的发育率无显著差异 ,但卵巢表面有红体和卵泡的 POECs共培养组的 >4-细胞的发育率显著高于卵巢表面布满卵泡的 POECs共培养组 (P<0 .0 5 ) ;受精卵在共培养系统和非共培养系统中的卵裂率无显著差异 ,受精卵非共培养系统中 3~ 4-细胞的发育能力显著低于颗粒细胞共培养组 (P<0 .0 5 ) ,极显著低于 POECs共培养组 (P<0 .0 1) ,无能力突破 4-细胞继续发育 ,与颗粒细胞单层、POECs单层共培养的受精卵 >4-细胞的发育率分别为 2 4.0 %、5 3.8% ,差异显著 (P<0 .0 5 )。结果表明 ,共培养系统对胚胎体外发育的作用 ,一方面与体细胞类型有关 ,另一方面也受输卵管上皮细胞状态的影响  相似文献   
87.
针对不同物种采用不同方法培养小鼠、山羊和鸡输卵管上皮细胞(OECs)并检测上皮细胞纯度,在此基础上比较了它们支持小鼠胚胎发育的能力。结果表明,3种细胞都能很好地生长,培养的细胞几乎全为上皮细胞(Vi-mentin单克隆抗体检测显示,小鼠、山羊和鸡OECs的阳性细胞率分别为2.4±0.3、1.3±0.3和1.8±0.4)。昆明白小鼠原核胚与小鼠、山羊和鸡OECs共培养,发育到囊胚的比例分别为61.7%、57.2%和56.2%,差异不显著(P>0.05)。说明鸡和山羊OECs能很好地支持小鼠胚胎发育。  相似文献   
88.
The purpose of the study was to evaluate whether a period of co-culture with bovine oviduct epithelial cells (BOEC) could improve the tolerance of bisected bovine embryos to freezing and thawing. Day 6 embryos were bisected and the resulting demiembryos were stained with Hoechst 33342 and cell counts were made by counting intact blastomere nuclei. Of these, 11 were stained as freshly manufactured demiembryos, 25 after co-culture for 24 h with BOEC and 37 stained after 24 h co-culture and freezing and thawing. The staining revealed, that there was no significant difference in cell count of demiembryos that were stained immediately after bisection, compared to those, that were co-cultured for a 24 h period. Also, the co-cultured/frozen/thawed demiembryos had a significant decrease in cell numbers compared to the non-frozen demiembryos. We conclude, that a 24 h period of co-culture with BOEC does not result in appreciable cellular proliferation in demiembryos and therefore instead of improving the survival of frozen/thawed demiembryos by giving them opportunity to multiply their cell number and thus make them more resistant to cell damage, rather compromised the viability of cryopreserved demiembryos.  相似文献   
89.
Using bio-guided fractionation and based on the inhibitory activities of nitric oxide (NO) and prostaglandin E2 (PGE2), eight isoquinolinequinone derivatives (1–8) were isolated from the marine sponge Haliclona sp. Among these, methyl O-demethylrenierate (1) is a noble ester, whereas compounds 2 and 3 are new O-demethyl derivatives of known isoquinolinequinones. Compound 8 was assigned as a new 21-dehydroxyrenieramycin F. Anti-inflammatory activities of the isolated compounds were tested in a co-culture system of human epithelial Caco-2 and THP-1 macrophages. The isolated derivatives showed variable activities. O-demethyl renierone (5) showed the highest activity, while 3 and 7 showed moderate activities. These bioactive isoquinolinequinones inhibited lipopolysaccharide and interferon gamma-induced production of NO and PGE2. Expression of inducible nitric oxide synthase, cyclooxygenase-2, and the phosphorylation of MAPKs were down-regulated in response to the inhibition of NF-κB nuclear translocation. In addition, nuclear translocation was markedly promoted with a subsequent increase in the expression of HO-1. Structure-activity relationship studies showed that the hydroxyl group in 3 and 5, and the N-formyl group in 7 may be key functional groups responsible for their anti-inflammatory activities. These findings suggest the potential use of Haliclona sp. and its metabolites as pharmaceuticals treating inflammation-related diseases including inflammatory bowel disease.  相似文献   
90.
李聪  成永旭  管勤壮  奚业文  李嘉尧 《水产学报》2018,42(11):1778-1786
为改善克氏原螯虾在稻—虾共作模式下对稻田中丰富自然资源的利用效率,本研究通过在饲料中添加碳源(麸皮、葡萄糖)调节饲料"碳/氮"(C/N)分别为8,12,16三个组别进行投喂,利用稳定性同位素技术分析各组克氏原螯虾的食性。结果显示,(1)不同C/N投喂组中不同规格成虾肌肉中的δ13C和δ15N值均较本底显著降低,成虾肌肉的δ13C值随投喂饲料C/N的增加而下降,B组不同规格成虾肌肉的δ15N值均较其他两组高。同一C/N投喂处理组中,1级小规格成虾肌肉的δ13C和δ15N值均为最高。(2)通过食性分析,组A中不同规格的克氏原螯虾的第一食物来源均为饲料,占比38.03%~44.17%,组B中饲料仍为不同规格克氏原螯虾的第一食物来源,但是占比下降为22.13%~25.35%,组C中1级小规格成虾中有机碎屑为第一食物来源,占19.93%,2级中规格成虾及3级大规格成虾的第一食物来源饲料进一步下降为18.85%和19.40%,组B及组C中浮游动物、藻类、喜旱莲子草等天然饵料食物来源占比均较组A显著增加。研究表明,通过优化C/N的投喂模式,可以提高克氏原螯虾对于稻田天然饵料的利用率,避免饲料的过度使用和浪费,有利于实现对稻田资源的合理利用。  相似文献   
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