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排序方式: 共有298条查询结果,搜索用时 15 毫秒
81.
欧李试管苗生根与移栽技术的研究 总被引:2,自引:0,他引:2
对欧李试管苗进行生根与移栽试验结果表明,欧李试管苗生根适宜的培养基配方为:MS+IAA3.0mg/L+PP3330.05mg/L+蔗糖20g/L+琼脂7g/L,培养23d,生根率达80%以上。移栽时用灭过菌而且通气透水性强的栽培基质为好,移栽成活率达80%以上。 相似文献
82.
Cultured beef is a method where stem cells from skeletal muscle of cows are cultured in vitro to gain edible muscle tissue. For large-scale production of cultured beef, the culture technique needs to become more efficient than today’s 2-dimensional(2D) standard technique that was used to make the first cultured hamburger. Options for efficient large-scale production of stem cells are to culture cells on microcarriers, either in suspension or in a packed bed bioreactor, or to culture aggregated cells in suspension. We discuss the pros and cons of these systems as well as the possibilities to use the systems for tissue culture. Either of the production systems needs to be optimized to achieve an efficient production of cultured beef. It is anticipated that the optimization of large-scale cell culture as performed for other stem cells can be translated into successful protocols for bovine satellite cells resulting in resource and cost efficient cultured beef. 相似文献
83.
Consumer acceptance of cultured meat is expected to depend on a wide diversity of determinants ranging from technology-related perceptions to product-speciifc expectations, and including wider contextu... 相似文献
84.
Genetic variation of wild and cultured populations of the Kuruma prawn Marsupenaeus japonicus (Bate 1888) using microsatellites 总被引:1,自引:0,他引:1
The microsatellite DNA technique was used to detect the genetic variations between wild and cultured populations of Kuruma prawn Marsupenaeus japonicus Bate 1888. All the six microsatellite loci screened in this study showed high polymorphism for their PIC (0.6701–0.8989), which was much more than the standard value of 0.5. A total of 73 alleles were observed over six loci from 93 shrimps. The mean number of allele locus ranged from 9.83 (cultured) to 11.83 (wild). The number of effective alleles varied from 6.86 (cultured) to 8.58 (wild). The average of observed heterozygosity (Ho) of populations varied from 0.6935 (cultured) to 0.7370 (wild), and that of expected heterozygosity (He) was 0.8169 (wild) and 0.8209 (cultured). Tests of Hardy–Weinberg showed that these loci deviated significantly or highly significantly in one or both populations. Compared with the wild population, the cultured population showed little reduction in genetic variation. The total number of alleles (71, 59) was not significantly (P=0.296) different between wild and cultured populations. The paired‐samples t test of observed heterozygosity and expected heterozygosity implied that there was no significant difference (P=0.572 and 0.891 respectively) between wild and cultured populations. However, some rare allele loss might have occurred in the cultured population. A total of 14 unique alleles were found in the wild population, but only two unique alleles were observed in the cultured population. Therefore, there is a need to monitor genetic variability of cultured population, and to improve the hatchery program for the conservation of wild Kuruma prawn resources. 相似文献
85.
采用聚丙烯酰胺凝胶电泳(PAGE)和RAPD方法对厦门养殖斑节对虾(Penaeus monodon Fabricius)群体的遗传多样性进行分析。9种同工酶共检测到21个座位,其中多态座位13个,多态座位比例为61.90%,预期杂合度0.151,观察杂合度0.120,Hardy—Weinberg遗传偏离指数(d)为-0.208,存在杂合子缺失。经x^2拟合度检验,多数座位偏离Hardy—Weinberg平衡,表明群体未达到随机交配。14个10bp引物共获得了83个标记,单个引物获得的标记数为2~11个,平均每个引物扩增出5.93个座位,其中多态标记数68个,多态位点比例为81.93%,杂合度为0.246,基因多样性为0.260,Shannon’S信息指数为0.397。两种方法均表明该斑节对虾养殖群体的遗传多样性水平较高,但可能已有近交衰退发生。 相似文献
86.
Yoshi -Nori Nakamura Masashi Ando Manabu Seoka Ken-ichi Kawasaki Yasuyuki Tsukamasa 《Fisheries Science》2007,73(5):1155-1159
ABSTRACT: Using the dorsal ordinary muscle (DOM) of cultured Pacific bluefin tuna (body length [BL]: 47.5–81.8 cm, body weight [BW]: 2.1–13.5 kg, n = 15), the changes of proximate compositions and myoglobin (Mb) content with growth were investigated. There was a positive correlation ( r = 0.9832, P < 0.05) of BL and BW in cultured tuna. The protein contents of the DOM of cultured tuna decreased ( P < 0.05) and the lipid contents had a tendency to increase (not significantly) with growth. The meat color changed from pink to red with growth. In addition, the Mb contents of the DOM of cultured tuna increased ( P < 0.05) from 1.0 mg/g (minimum BW fish) to 3.8 mg/g (maximum BW fish) with growth. These results indicate that the increase of the Mb content in the DOM of cultured tuna is not caused by the restriction of exercise and overfeeding between 2.1 kg and 13.5 kg of BW. 相似文献
87.
AIM: To study apoptotic injury induced by reactive oxygen species-hydrogen peroxide (H2O2) on cardiac myocytes.METHODS:Cultured rat neonatal cardiac myocytes were treated with H2O2 of various concentration to observe apoptotic injury of cardiomyocytes by agarose gel electrophoresis, Giemsa-stained smears of cell, and flow cytometry, meanwhile lactate dehydrogenas (LDH) and malondialdehyde(MDA) were determined to assess the effect of H2O2 on lipid peroxidation and permeability of the plasma membrane. RESULTS: 5 mmol/L H2O2 caused cultured cardiomyocytes apoptotic morphological characteristics, including nucleosomal DNA fragmentation in myocytes by agarose gel electrophoresis (DNA ladder), cell shrinkage, nuclear condensation, and chromatin margin by Giemsa-stained cell smears, and aneuploid peak(AP)-apoptotic bodies occurrence by flow cytometry.CONCLUSIONS: H2O2-induced apoptosis in myocytes was a time-and concentration-dependent process. Treatment with low concentration of H2O2(<1 mmol/L) only caused cardiomyocyted early biochemical changes, such as increase of free radicals level and membrane permeability ,which were pro-apoptotic injurious features. High concentration of H2O2 (>10 mmol/L) rapidly induced a necrotic form of death characterized by smeared patterns of DNA digestion on agarose gel electrophoresis and lethal membrane disruption (as measured by LDH release). Exposure of 5~10 mmol/L H2O2 induced cardiomyocytes apoptosis concurrently with biochemical changes of LDH and MDA increase in the medium. 相似文献
88.
对高浓度THF作用下污水处理厂曝气池回流污泥的pH、溶氧、可培养微生物连续测定6周,观察到回流污泥的pH随着THF浓度的增加和培养时间的延长而上升;四氢呋喃的存在可极大地抑制回流污泥中微生物的好氧呼吸强度,导致氧的消耗减少,且培养4周时,回流污泥中溶氧显著高于其他培养时段时的溶氧;在含有THF的回流污泥中,可培养细菌的数量在培养4周时出现峰值,可培养放线菌的数量在培养3周时出现峰值,可培养真菌的数量未出现明显峰值。 相似文献
89.
研究了在促进剂Cu2+和抑制剂2,4-D及光的作用下,对产色素培养细胞紫草宁形成的影响。对4,15,25,35和45d的紫草培养细胞的电镜观察和细胞超微结构分析的结果表明,15d加促进剂Cu2+的新疆紫草培养细胞形成的色素颗粒(紫草宁)最多,4d和加抑制剂2,4-D的培养细胞中均无明显的色素颗粒。 相似文献
90.
Macro‐geographical differences influenced by family‐based expression on cultured pearl grade,shape and colour in the black‐lip ‘pearl oyster’ Pinctada margaritifera: a preliminary bi‐local case study in French Polynesia
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Chin‐Long Ky Carole Blay Vaite Aiho Philippe Cabral Gilles Le Moullac Cédrik Lo 《Aquaculture Research》2017,48(1):270-282
In French Polynesia, the aquaculture of Pinctada margaritifera is carried out in numerous grow‐out sites, located over three archipelagos (Gambier, Society and Tuamotu). To evaluate the impact of macro‐geographical effects of these growing sites on pearl quality traits, five hatcheries produced families were used as homogeneous donor oysters in an experimental graft. The molluscs were then reared in two commercial locations: Tahaa Island (Society) and Rangiroa atoll (Tuamotu). At harvest, eight pearl quality traits were recorded and compared: surface defects, lustre, grade, circles, shape categories, darkness level, body and secondary colour and visual colour categories. Overall inter‐site comparison revealed that: (1) all traits were affected by grow‐out location except for lustre and round shape, and (2) a higher mean rate of valuable pearls was produced in Rangiroa. Indeed, for pearl grade, Rangiroa showed twice as many A‐B and less reject samples than Tahaa. This was related to the number of surface defects (grade component): in Rangiroa, twice as many pearls had no defects and less pearls had up to 10 defects. Concerning pearl shape, more circled and baroque pearls were found in Tahaa (+10%). For colour variation, 10% more pearls have an attractive green overtone in Rangiroa than in Tahaa, where more grey body colour were harvested. Lustre does not seem to be affected by these two culture site (except at a family scale). This is the first time P. margaritifera donor family have been shown to vary in the quality of pearls they produce depending on their grow‐out location. 相似文献