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排序方式: 共有186条查询结果,搜索用时 15 毫秒
81.
Using three varieties of Brassica campestris, Hauarad (708), Maoshan-3 (714) and Youbai (715),as the maternal plants and one variety of Brassica oleracea Jingfeng-1 (6012) as paternal plants, crosses were made to produce interspecific hybrids through ovary culture techniques.The ovaries from the cross between B. campestris × B.oleracea (708 × 6012 and 714 × 6012) were cultured and ovary culture was more effective in terms of obtained seeds when ovaries were cultured in vitro at 9 d after pollination (DAP). While for the cross of 715 × 6012, it was better when ovaries in vitro cultured at 12 DAP. Among three cross combinations, the cross of 714 × 6012 showed the best response and 43 seeds per ovary were obtained. Among the media studied, the ovaries from the cross of 708 × 6012 cultured on MS media supplemented with 3.0 mg L-1 BA × 0.1 mg L-1 NAA showed better response, and its rate of seeds per ovary reached 44.0%.While the ovaries from the other two crosses (714 × 6012 and 715 × 6012) showed the best response when cultured on B5 media supplemented with 3.0 mg L-1 BA + 0.2 mg L-1 NAA, and the rates of seeds per ovary reached 72.0 and 60.0%, respectively. All seeds obtained from the three cross combinations were cultured on the MS media supplemented with 1.0 mg L-1 BA + 0.05 mg L-1 NAA,and the seeds from the cross of 715 × 6012 showed the best germination response and the percentage of germinations reached 66.7%. The regenerated plantlets were obtained from these seedlings after cultured on the MS media supplemented with 0.05 mg L-1 NAA. Cytological study showed that these regenerated plants were all true hybrids of B.campestris × B.oleracea. 相似文献
82.
González-Morán MG 《Domestic animal endocrinology》2007,33(2):154-166
The effect of the luteinizing hormone (LH) on the oogenesis of ovaries from newly-hatched chicks treated in vivo on days 13, 15, and 17 of embryonic development was analyzed. Changes in oogonial proliferation, meiotic prophase, degeneration of germ cells, and primordial follicular organization were determined. Results indicate that the total number of germ cells was not affected by the LH treatment, but significant differences existed in the number of oogonia and oocytes between the ovaries of control and LH-treated chicks. LH treatment increased the percentage of oocytes and diminished the percentage of oogonia. The mitotic activity of oogonia and degeneration of germ cells decreased, but the number of follicles during development increased in LH-treated ovaries. These findings suggest that LH treatment might trigger a cascade of endocrine events, resulting in inhibition of oogonial proliferation and induction of the meiotic prophase and follicle formation. 相似文献
83.
三种多胺在苹果开花及坐果初期的生理作用 总被引:31,自引:2,他引:31
研究了苹果开花过程中花药、幼果(花托和子房)和贮藏花粉内源腐胺(Put)、亚精胺(Spd)、精胺(SPin)的含量变化及外源3种多胺对花粉萌发、雌蕊寿命和坐果的影响。结果表明:在开花过程中,花药中3种多胺的含量逐渐降低,花粉中的含量在贮藏期间和荫芽率同步降低;3种多胺浴液浸泡的花粉,其萌发率和花粉管长度极显著提高和增长;从蕾期到第一次生理落果,幼果多胺含量呈下降趋势,但受精幼果比未受精幼果的下降速度缓慢;第一次生理落果期,幼果内源多胺含量降到最低点;用3种外源多胺喷布花蕾,均延长了雌蕊寿命,增强了受精能力,提高了坐果率。 相似文献
84.
85.
本研究系采用中西兽医结合的方法,首次应用国产LRH-A穴位注射后海穴、百会穴和催情穴(任选一穴)治疗因卵巢机能失调所造成的不孕症奶牛共177例,总有效率达73.6~100%,与肌肉注射疗法比较,提高疗效10.7%左右,用药量比肌肉注射节省2/3~4/5,取得了满意效果。在探索其治疗机理方面,测定了血浆中孕酮(P)和17β一雌二醇(E_2)的含量变化,提供了一定依据。 相似文献
86.
应用免疫细胞化学方法对白血病抑制因子(leukemiainhibitoryfactor,LIF)、白血病抑制因子受体(leukemiainhibitoryfactorreceptor,LIFR)和gp130在月经周期猕猴卵巢内的表达进行了研究。结果表明:LIF、LIFR和gp130在猕猴卵巢内的表达量随月经周期的不同而变化,LIF及其受体在增殖期卵巢内的表达量高于分泌期的卵巢。LIF及其受体在原始卵泡、腔前卵泡和有腔卵泡的卵细胞内表达量均较高,在颗粒细胞、卵泡膜、卵巢生殖上皮和卵巢基质中有少量表达,而在闭锁卵泡、退化的黄体和卵巢髓质中未见表达。LIF及其受体在猕猴卵巢内的表达可能受卵巢分泌的类固醇激素所调控,LIF可能通过自分泌或旁分泌的方式在猕猴卵泡发育及排卵等过程中起重要作用。 相似文献
87.
Background
The effects of seminal plasma on the presence of the cytokines transforming growth factor (TGF)-β1, interleukin (IL)-10 and IL-6 in ovarian follicles and follicular fluid were studied shortly after insemination in gilts.Ovaries from gilts were sampled 5–6 h after insemination with either seminal plasma (SP), fresh semen in extender (Beltsville thawing solution, BTS), spermatozoa in extender (Spz), or only BTS (control).Results
Immunohistochemical (IHC) labeling of TGF-β1, IL-10 and IL-6 was evident in the ovarian oocytes and granulosa cells independent of stage of follicular development (antral follicles). Theca interna cells were labeled to a high degree in mature follicles. No consistent differences between treatment groups could be observed for any of the cytokines.In follicular fluid, high concentrations of TGF-β1 were found while the levels of IL-10 and IL-6 were low. There were no differences between treatment groups.Conclusions
Our results show a presence of the cytokines TGF-β1, IL-6 and IL-10 in oocytes, granulosa and theca cells, as well as in the fluid of mature follicles suggesting a role of these cytokines in intra-ovarian cell communication. However, treatment (SP, fresh semen in BTS, spermatozoa in BTS or BTS) did not influence the IHC-labeling pattern or the levels of these cytokines in follicular fluid shortly after insemination. 相似文献88.
以色素万寿菊雄性不育株未授粉子房为外植体,比较研究子房发育期、高低温处理和生长调节剂组合对愈伤组织诱导和分化的影响。结果显示:发育6~10 d,花丝刚好露出花萼,顶部呈圆柱状的花蕾愈伤组织诱导效果最好,为79.2%;低温预处理3 d,高温培养5 d有利于愈伤组织诱导;MS+2,4-D 0.5 mg/L+NAA0.5 mg/L+6-BA 0.5 mg/L+KT 0.5 mg/L为愈伤组织诱导最佳培养基,诱导率高达85.8%;NAA 1.0 mg/L+6-BA3.0 mg/L为不定芽分化适宜培养基,分化率达77.6%;1/2MS+NAA 0.2 mg/L为生根适宜培养基,生根率93.5%。本研究可为建立高效单倍体培养体系以及单倍体育种技术提供基础性资料。 相似文献
89.
抑制消减杂交技术筛选鹅产蛋期差异表达基因 总被引:1,自引:0,他引:1
[目的]鉴定筛选鹅产蛋与就巢差异表达基因。[方法]应用抑制消减杂交技术构建鹅产蛋与就巢鹅卵巢组织双向cDNA文库,获得差异表达基因。[结果]从双向文库随机挑选单菌落进行PCR验证,结果表明文库质量良好。选取654个阳性克隆进行测序分析,获得641条表达序列标签(ESTs)。对ESTs进行去除载体序列、质量检测、聚类及拼接,经Blast比对,有166条ESTs找到与之匹配的同源序列,其中92个是功能基因。[结论]比较就巢与产蛋SSH文库,发现产蛋特异性基因文库中参与物质能量代谢、细胞防御的基因较多,而在就巢SSH库中参与细胞凋亡、信号转导及细胞结构的基因出现频率较高。该结果对进一步研究鹅卵泡发育及繁殖力分子标记筛选打下了基础。 相似文献
90.
A. Supriya K. Raghuveer I. Swapna M. K. Rasheeda T. Kobayashi Y. Nagahama Aparna Dutta Gupta K. C. Majumdar B. Senthilkumaran 《Fish physiology and biochemistry》2005,31(2-3):267-270
In the present study, thiourea-induced thyroid hormone depletion and thyroxine (T4) ‘overdose’ were used as a strategy to understand the influence of thyroid hormones on ovarian recrudescence of juvenile
(3-months-old), immature (8-months-old) and adult (1-year-old) air-breathing catfish, Clarias gariepinus. Thiourea-induced thyroid hormone depletion in juvenile catfish impaired ovarian development, but no significant effect was
observed in immature catfish and during late stage of ovarian recrudescence of mature catfish. T4 treatment in females undergoing late stages of ovarian recrudescence induced rapid oocyte growth by promoting its early entry
into maturational phase as evident from the presence of more number of vitellogenic and post-vitellogenic follicles, decrease
in aromatse immunoreactivity and reduced estradiol–17β levels. Hence, thyroid hormones have an important role to play during early stages of ovarian development and vitellogenesis
of catfish and also indicating that thyroid has a stage dependent effect on ovary. 相似文献