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81.
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   
82.
观察得知,茶壶枣果实形状个体之间存在着较大差异,茶壶枣的果实不同于骏枣等品种,是由子房、蜜盘、花丝残留组织共同膨大发育形成,而不是单纯由子房膨大发育形成;茶壶枣由于花芽分化不完善,花丝难以与蜜盘或子房分离,开花后花药脱落,留在蜜盘上的花丝组织残迹随蜜盘一起膨大发育而形成果实上的肉状突起。  相似文献   
83.
【研究目的】为了探讨镉对性未成熟鸡卵巢发育的毒性机制,从分子水平阐述镉中毒的发病机理,增强人类环境保护意识,避免畜、禽镉中毒的发生。【方法】在饲料中加入140mg/kgCdCl2、210mg/kgCdCl2建立亚慢性镉中毒模型,分别在试验20d、40d、60d取卵巢称重,进行Na -K -ATPase,Mg2 -ATPase和Ca2 -ATPase活性检测。【结果】对照组卵巢组织内Na -K -ATPase,Mg2 -ATPase和Ca2 -ATPase活性随日龄增加呈上升趋势,各时间点酶活性比较差异不显著;加镉组卵巢组织内Na -K -ATPase,Mg2 -ATPase和Ca2 -ATPase活性随日龄增加呈降低趋势,与对照组比较差异显著或极限著,且呈一定的时间-剂量效应。【结论】镉能够抑制性未成熟鸡卵巢发育,降低卵巢组织ATPase活性,二者存在一定相关性。  相似文献   
84.

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   
85.
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   
86.
小麦花粉管通道法转基因研究   总被引:6,自引:1,他引:6  
为了培育抗穗发芽的种质资源,以13个小麦品种(品系)的植株体为受体材料,用花粉管通道及子房注射法进行了硫氧还蛋白反义基因(Anti-TrxS,与穗发芽抗性有直接关系)的遗传转化。花粉管通道法共处理小花2036朵,收获T0代种子1616粒,结实率为79.4%,将T0代种子大田点播成株行,T1代共出苗1424棵,出苗率为88.1%。对T1代苗按品种和处理组合的方式进行抽样检测,抽样株系取10个单株分别提取叶片基因组DNA,然后将单株叶片DNA等量混合,进行株系基因组DNA的PCR检测。检测结果为31个株系中有16个株系呈阳性反应。子房注射法共转化豫麦49、豫麦70、豫麦18、郑新991和95519等5个小麦品种(品系)的小花1206朵,收获种子89粒,结实率为7.4%,T1代共出苗41棵,出苗率为46.1%。对郑新991T1代株系(12棵幼苗的叶片基因组DNA混合样)进行PCR检测,电泳结果呈阳性反应。  相似文献   
87.
Gossypol is a polyphenol isolated from the seed, roots and stem of cotton plant (Gossypium sp.) It has been associated with adverse effects on female reproduction, but recently also shown having promising effects against several malignancies. Its mechanisms of action are however still not fully understood. This study was therefore conducted to investigate the effect of 5 or 25 μg/mL gossypol on swine granulosa cell steroidogenic activity, redox status and Vascular Endothelial Growth Factor (VEGF) production. Study demonstrated that gossypol significantly (P < 0.001) inhibited granulosa cell estradiol 17β and progesterone production, an effect that could be at least partially mediated by an increase (P < 0.05) of nitric oxide and superoxide anion production as a consequence of superoxide dismutase inhibition. Moreover, gossypol stimulates (P < 0.001) VEGF production. In conclusion, study has demonstrated effecs of gossypol on swine granulosa cell function in vitro. Effects on female swine fertility can not be excluded.  相似文献   
88.
鸡生殖器官的组织学特点   总被引:5,自引:0,他引:5  
通过对5例健康成年罗曼鸡的生殖器官的组织学观察,结果表明:1)鸡睾丸曲细精管生精上皮形成多个细胞柱,各团细胞柱独立完成精子的发生;2)卵巢的的间质内可见到大量成堆分布的嗜酸性粒细胞,这种现象可能与机体的防御能力有关;3)在输卵管的子宫-阴道连接部的粘膜皱襞内存在有精子寄生腺,腺体内的分泌物可较长时间的保持精子的活力。  相似文献   
89.
细胞因子是一类具有广泛生物学效应的可溶性多肽.动物卵巢的多种组织中都有IL-1、TNF等细胞因子及其受体存在,因此它们在卵巢生殖活动中所起的作用越来越被人们重视.细胞因子可通过自分泌或旁分泌途径影响卵泡、黄体形态和功能.  相似文献   
90.
Body condition scoring (BCS) is widely used to evaluate the nutritional status of livestock (cows, ewes, sows). In intensive systems, rabbit does are generally inseminated 11 days post partum and, due to a hormonal antagonism and an energy deficit caused by concurrent lactation and pregnancy, they show low fertility. The aim of this investigation was to assess an in vivo method for scoring the body condition of does by verifying the association with the body fat depots, the chemical composition of body tissues, the ovarian status, the hormonal response and the reproductive performance. The evaluation of BCS, involving 66 multiparous lactating does inseminated at 11 days post partum, was based on the test of bone protrusions and fullness of muscle of the loin, rump and hind leg. The traits were subjectively scored using 0, 1 and 2 for poor, intermediate and good condition, respectively. For calculating an aggregate BCS, the hind leg score was omitted, because it is less correlated with the real body condition. Adding the respective score (0–2) of the loin and rump regions, 5 classes of BCS were obtained (0–4). This aggregate BCS was highly correlated with the body fat depots (r = 0.79), the ether extract content of muscle samples of Obliquus abdominis (r = 0.87) and Biceps femoris (r = 0.84), and the ether extract of the empty body (r = 0.84). There was a lower correlation with the body weight (r = 0.45). The increase of BCS corresponded to higher lipid content in the body parts considered, especially the Obliquus abdominis (from 2.0 to 10.0%) and fat depots (from 10.6 to 107.7 g/doe). BCS was not related to ovulation rate or embryo production, but was correlated with sexual receptivity and fertility.Plasma FSH and LH concentrations were determined by RIA, 48, 24, 0 h before and 1 h after GnRH administration and artificial insemination. Animals with extreme body condition scores (BCS ≤ 1 or BCS = 4) showed lower plasma FSH levels (20.0 vs. 34.5 ng/mL) than does with optimal body condition (2 ≤ BCS ≤ 3) and their preovulatory LH surge, released after GnRH administration, was less evident (16.9 vs. 20.3 ng/mL). The poor reproductive performance of does with extreme BCS could be explained by this pituitary activity. On day 11 post-partum, a high number of does (71.2%) had extreme BCS and showed a lower sexual receptivity (37.2% vs. 80.0%) and fertility rate (50.9% vs. 86.6%) than does in optimal condition. On these results, the possibility of applying an in vivo method for scoring the body condition of lactating rabbit does appears promising for use in on-farm reproductive management.  相似文献   
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