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51.
中间锦鸡儿硬枝扦插试验 总被引:2,自引:0,他引:2
以中间锦鸡儿为材料进行了硬枝扦插试验,在珍珠岩和粗沙2种不同的基质上进行扦插,分别采用不同浓度的吲哚丁酸(IBA)、奈乙酸(NAA)、ABT1#、ABT2#生根粉进行处理。试验表明:粗沙硬枝扦插较为理想,平均生根率较珍珠岩提高14.1%;不同激素种类对中间锦鸡儿硬枝插穗生根情况影响极显著,珍珠岩基质上扦插,以ABT1#100 ppm和200 ppm生根效果最佳;粗沙基质上扦插,处理浓度以IBA 1000 ppm、ABT1#500 ppm、ABT2#500 ppm对中间锦鸡儿硬枝扦插生根效果最佳。 相似文献
52.
AIM: To investigate the effects of gonadotropin-releasing hormone (GnRH) analogue on the growth of breast cancer cell lines MCF-7 and MDA-MB-231 in vitro and to explore the related mechanisms with PI3K/Akt or ERK/MAPK pathways. METHODS: The proliferation of human breast cancer cell lines MCF-7 and MDA-MB-231 treatment with triptorelin was detected by MTT assay and the distribution of the cell cycle was determined by flow cytometry. The phosphorylation of the ERK1/2 and Akt was evaluated by Western blotting. RESULTS: Triptorelin inhibited the proliferation of MCF-7 cells at concentration of 10-5 mol/L after treated for 192 h or at concentration of 10-4 mol/L after treated for 168 h and 192 h. Triptorelin inhibited the proliferation of MDA-MB-231 cells at concentration of 10-4 mol/L after treated for 192 h (P<0.05).Treatment with triptorelin for 192 h at concentration of 10-4 mol/L had no statistical significance effect on phosphorylation of ERK1/2 and Akt(P>0.05).CONCLUSION: Inhibitory effect of GnRH analogue triptorelin on human breast cancer cells is not just the connection with the down-regulation of pituitary hormone, but also a direct inhibitory effect. The role may not be involved in the activation of ERK/MAPK and PI3K/Akt signaling pathways. 相似文献
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几年来,广西象州县的多个牛人工授精品改点的受胎率,黄牛为40%~50%,水牛为30%~40%,在这样的情况下,牛的受胎率有待提高。人绒毛膜促性腺激素在母牛体内具有促进卵泡发育、排卵的作用;利用人绒毛膜促性腺激素的这一特性,在母牛发情时肌肉注射,然后进行输精,观察对母牛的受胎率的影响,是否能够提高牛人工授精工作的效益。结果显示,在牛人工授精工作中使用了人绒毛膜促性腺激素,能够提高受胎率,也提高了工作效益。 相似文献
55.
Paolo Borghetti Roberta SaleriLuca Ferrari Marina MorgantiElena De Angelis Valentina FranceschiEzio Bottarelli Paolo Martelli 《Comparative immunology, microbiology and infectious diseases》2011,34(2):143-155
The objective of this paper was to study the changes of some cytokines and neuroendocrine hormones in vaccinated and unvaccinated pigs that were naturally infected by a PRRSV-1 (porcine reproductive and respiratory syndrome virus) heterologous field strain. We analyzed gene expression of pro-inflammatory (TNF-α, IL-1β, MCP-1, IL-6), pro-immune (IFN-γ) and anti-inflammatory cytokines (IL-10) in PBMC, as well as hormonal (GH and cortisol) levels in blood samples of pigs obtained in a field trial previously reported [Martelli P, Gozio S, Ferrari L, Rosina S, De Angelis E, Quintavalla C, et al. Efficacy of a modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine in pigs naturally exposed to a heterologous European (Italian cluster) field strain: clinical protection and cell-mediated immunity. Vaccine 2009;27:3788-99]. All vaccinated pigs showed an increase in pro-inflammatory and pro-immune cytokine gene expression with respect to controls and a prompt increase in GH that could be consistently associated with pro-inflammatory cytokines in sustaining innate immunity; moreover, the higher levels of cortisol indicates the activation of the hypothalamus-pituitary-adrenal (HPA) axis response. In contrast, unvaccinated pigs showed down-regulation of the cortisol and GH responses, and the pro-inflammatory and pro-immune cytokines remained at a basal or low level, with an increase of TNF-α and IL-6 in association with a higher level of IL-10 in the late phase of natural infection. The associated trends of pro-inflammatory and anti-inflammatory cytokines together with the cortisol level demonstrate that a previous vaccination promotes an early immune responsiveness in pigs and a more efficient control of inflammation in the late phase of infection with a heterologous PRRSV isolate; both events could sustain clinical protection. 相似文献
56.
鸵鸟主要性激素分泌规律的研究 总被引:2,自引:2,他引:0
本研究旨在观察鸵鸟一年中激素分泌规律与发情行为的相关性,为采精和输精掌握最准确的时间,采用放射免疫分析法(RIA)测定样品中促卵泡刺激素(FSH)、雌激素(E2)和睾酮(T)的浓度水平。结果表明:①雌鸵鸟血浆内FSH水平在一年之中呈现波动式变化,从11月开始上升,12、2、7月中出现3个明显的分泌波峰,峰值分别为114.354、130.168和144.375 mIU/mL,6月中旬达到全年中最低22.312 mIU/mL;②E2水平在1~5月都呈缓慢上升趋势,在7月突然下降到最低(18.874 pg/mL),9月达全年最高峰(367.285 pg/mL);③雄鸵鸟血浆睾酮(T)浓度从1~6月一直呈上升趋势,6月达到较高水平(121.473 ng/dL),8月达到全年中最低(77.166 pg/dL),到10月中旬达到全年最高(138.562 ng/dL);鸵鸟血浆内FSH、E2及T的浓度水平在一年之中呈现波动式变化与发情表现趋于一致。 相似文献
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AIM: To establish a method for determining the differential expression of proteins in human endometrium during the implantation window and to analyze the correlation between altered expression of the proteins and endometrial receptivity. METHODS: A comparative proteomic strategy in a combination of two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was adopted to search the proteomic alternations in the endometria of pre-receptive pre-receptive [day 2 after luteinizing hormone surge (LH+2 d)] state versus the endometria of receptive (LH+7 d) state. Validation of annexin IV was performed by Western blotting. RESULTS: Approximate 2 555±98 polypeptide spots were revealed by densitometry analysis of the 2D protein maps in LH+2 d and LH+7 d endometrial tissues resolved in the linear range of pH 3~10 on the 2D gel, in which 31 proteins were found to be significantly changed, including 17 proteins up-regulated and 14 proteins down-regulated in LH+7 d samples. These 31 identified proteins were classified into 6 functional categories of the correlation with implantation process: cell migration or assimilation, enzymic activity, signal transduction and gene regulation, immunoregulation, vascularization, and blood clotting or fibrinolysis system. The same expression trend of annexin IV was confirmed by Western blotting. CONCLUSION: Human endometrium has a differential proteomic repertoire during the window of implantation. The 6 functional categories of differentially expressed proteins in the receptive endometrium indicate that they play an important role in transforming of the endometrium during the receptive state. 相似文献
59.
《Scandinavian Journal of Forest Research》2012,27(1-4):465-479
Two “classical” theories, both originating in Elias Melin's laboratory in Uppsala, have tried to explain the regulation of ectomycorrhiza formation. The carbohydrate theory, formulated by E. Björkman in 1942, identifies root carbohydrate concentrations as regulatory, while these are in turn considered to be strongly influenced by plant mineral nutrition and light conditions. The hormone theory, expounded by V. Slankis in the 1960s, claims auxin of fungal origin to be the key regulator, influencing root carbohydrate status, while the fungus itself may, to some extent, be affected by mineral nutrition. Both theories have been subject to much discussion and have led to further work, without ever having been conclusively proven experimentally. Recent results in Uppsala and elsewhere have shed new light on several of the key issues. The development of research in this field since 1942 is critically reviewed in light of later data, and a unifying theory is sketched on the basis of E. Hacskaylo's proposal from 1969 to reconcile contradictory results. 相似文献
60.
丛枝菌根真菌对番茄植株内源激素含量的影响 总被引:3,自引:0,他引:3
于温室盆栽条件下对番茄(Lycospersicon esukurentamu)幼苗接种丛枝菌根(AM)真菌摩西球囊霉(Glomusmosseae)、地表球囊霉(Glomus versiforme)、根内球囊霉(Glomus intraradices)、幼套球囊霉(Glomus etunicatum)或珠状巨孢囊霉(Gigaspora margarita)10d后定期采样,应用间接酶联免疫吸附分析法(ELISA)测定各处理番茄植株根和叶片内源激素吲哚乙酸(IAA)、赤霉素(GA)、玉米素核苷(ZR)和脱落酸(ABA)含量。接种20d G.mosseae处理的番茄根系菌根侵染率高达68.5%,显著高于其他接种处理;供试AM真菌显著增加了番茄植株鲜重、株高、地上部和地下部干重、其根或叶内IAA、GA、ZR和ABA含量均显著高于不接种对照,以G.mosseae处理的根或叶中IAA、GA、ZR和ABA含量最高。 相似文献