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151.
152.
本试验以206小麦为母本,二棱大麦旱燕3号和六棱大麦原早1号为父本进进杂交。结果表明,两个组合早期的胚胎发育基本上是正常的,前者成胚率为8.75%,后者为16.8%。胚乳核最早于授粉后3天开始形成细胞。当胚乳细胞充满囊后,很快就转入迅速解体,胚随即停止生长,没有能够进一步分化出器官来。胚乳于授粉15天后,几乎全部败育,胚亦相继夭亡。胚胎发育过程中的不正常现象普遍存在。主要是极核受精过程遭受破坏;合子和初生胚乳核发育停滞;原胚虽能正常发育而胚乳没有形成;胚乳细胞过早形成和迅速解体等。讨论了杂交不孕和胚乳败育的原因。同时,提出了幼胚离体培养的适宜时间。 相似文献
153.
以走马胎(Ardisia gigantifolia)幼嫩茎段为外植体, 通过腋芽增殖的方式进行组织培养和快速繁殖研究。结果表明, 培养基MS+1.0 mg·L -1 6-BA+0.2 mg·L -1NAA和MS+0.5 mg·L -1 ZT均可用于腋芽的诱导和前期继代培养, 诱导率分别为89.3%和85.7%; 芽增殖最佳培养基为MS+0.5 mg·L -16-BA+0.1 mg·L -1ZT+0.1 mg·L -1NAA, 增殖系数为4.3倍; 根诱导最佳培养基为1/2MS+1.5 mg·L -1 IAA+1.0 mg·L -1 NAA, 生根率达92.3%, 且根系发达, 植株健壮; 生根苗在混合基质园土:泥炭:珍珠岩=3:1:1 (v/v/v )中移栽成活率为82%。该研究建立了走马胎种苗的组织培养快速繁殖技术体系, 且可应用于规模化生产。 相似文献
154.
借助二次通用旋转组合设计法研究了麦草栽培姬菇配方的数学模型,以探讨利用麦草替代棉籽壳的新配方.试验结果得出了配料的取值范围及最佳栽培配方,即麦草79%,麸皮15%,玉米粉4%,过磷酸钙1%,黄豆饼粉1%.在实际生产中很有应用价值. 相似文献
155.
畜禽遗传资源冷冻保存中的取样方法探讨 总被引:1,自引:0,他引:1
本文基于遗传学和数理统计原理,提出了运用冷冻生殖细胞的方法长期保存畜禽遗传资源时,冷冻生殖细胞的4种取样方法,并推证了其误差公式和最低保存数量的估计公式。最后通过实例对公式的实际应用作了说明和讨论分析。 相似文献
156.
157.
我国汉族人群的乙二醛酶Ⅰ遗传多态性 总被引:1,自引:0,他引:1
用琼脂糖平板凝胶电泳技术分析了我国六个城市的汉族共1238人的红细胞乙二醛酶I的遗传多态性。每个汉族人群的受检人数和GLO1*1基因频率分别为:郑州200人(0.1023),哈尔滨195人(0.1103),呼和浩特210人(0.1259),贵阳204人(0.1373),兰州210人(0.1476),西安199人(0.1508)。中国不同地区汉族人群之间的GLOI基因频率分布存在显著性差异,但这种差异明显小于中国不同少数民族之间的差异。 相似文献
158.
Previous studies from our laboratory have suggested that, in addition to an effect on spermatozoa in the testis, cyclophosphamide may have an adverse effect on spermatozoa after they leave the testis, during epididymal transit. To elaborate on this post-testicular effect on germ cells and to determine at which site(s) in the epididymis germ cells are most sensitive to cyclophosphamide treatment, three experiments were undertaken. First, the time course of the effect of treatment of male rats with cyclophosphamide on the outcome of their progeny was determined. Male rats were treated daily by gavage with saline or one of two doses of cyclophosphamide (6.8 mg/kg or 10.0 mg/kg) for 1, 4, or 7 days. At the end of each treatment period, males were mated to assess the effect on pregnancy outcome. No effect was observed on pre-implantation loss at any time among any of the groups, but there was a time-dependent and dose-related increase in post-implantation loss. Post-implantation loss was significantly increased after 4 days of treatment and reached nearly 40% after 7 days of drug exposure (10.0 mg/kg). Second, the effect of treatment with single high doses of cyclophosphamide was studied. Male rats were treated with a single dose of cyclophosphamide (10, 30, or 70 mg/kg) and bred 1 day and 4 days post-treatment. No significant change in pre-implantation loss was observed at either time point; no change in post-implantation loss was found after 1 day post-treatment. However, a significant increase in post-implantation loss was observed in the two high-dose groups 4 days post-treatment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
159.
160.
Momčilo Mihailović Paul Lindberg Ivan Jovanović Duŝan Antić 《Biological trace element research》1992,33(1-3):71-77
The selenium (Se) contents in common cereals in endemic and nonendemic areas in Serbia are very low. Plasma Se levels of both
patients and healthy subjects, were also low, reflecting low Se intakes. Patients with Balkan endemic nephropathy (BEN) had
significantly lower (p<0.05) plasma Se levels than healthy individuals, both from regions close to endemic areas, and from Belgrade. Mean plasma
Se of BEN patients was slightly but insignificantly higher in samples taken immediately after dialysis than in those taken
before, suggesting that very little of the Se present in plasma is dialyzable. Plasma SeGSH-Px activities before and after
hemodialysis in both BEN and Nonendemic chronic renal failure (NCRF) patients were not significantly different, but BEN patients
had lower enzyme activities than those with NCRF and healthy controls. In BEN patients, a significant correlation between
plasma Se and SeGSH-Px activity was found.
NCFR patients were with diagnoses: TBC of kidneys, chronic glomerulonephritis, chronic pyelonephritis, and polycystic kidneys. 相似文献