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121.
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   
122.
早杂7号是以J138-1-5-6-1-2为母本,以Z2-3-5-8-1为父本配制而成的早熟瓠瓜一代杂种。田间长势中等,早熟性优;商品瓜长35cm左右,横径6.0cm,单瓜质量0.6kg左右;瓜形匀称,瓜皮翠绿有光泽,品质好,VC含量高,坐果率高。适应性强,特别适合浙江、山东、福建等地保护地早熟栽培,也适合保护地秋延后栽培和露地栽培。  相似文献   
123.
小麦7D染色体数量性状基因定位和效应估计的研究   总被引:10,自引:0,他引:10  
李维明 Worl.  AJ 《作物学报》1996,22(6):641-646
综合应用方差分析法、区间定位法和联合定位法将控制抽穗期、有效穗数、小穗数、50粒重和单穗产量等5个性状的6个数量性状基因座(QTL)定位在小麦7D染色体上。其中控制粒重的QTL有2个。这些QTL集中分布在着丝粒附近和染色体长臂的末端两个区域。效应估计结果表明多数QTL的效应是微效的,控制同一个性状(粒重)的两个QTL的效应几乎相等。比较3种QTL定位法的分析结果,方差分析简单有效,且当染色体上只有  相似文献   
124.
We developed some wheat-Th. intermedium translocation lines,Yw642, Yw443 and Yw243, etc., showing good BYDV resistance from L1by induced homoeologous pairing using CS ph mutant. Characterization ofthese wheat lines was carried out by GISH and RFLP analysis. The resultsof GISH showed that the lines, YWw42, Yw443 and Yw243, etc., arehomozygous wheat-Th. intermedium translocation lines, in which thechromosome segments of Th. intermedium were transferred to thedistal end of a pair of wheat chromosomes. RFLP analysis indicated that thetranslocation chromosome of the wheat lines is T7DS · 7DL-7XL. Thebreakpoint of the translocation is located on the distal end of 7DL, betweenXpsr965 and Xpsr680 about 90–99 cm from the centromere. The BYDVgene is located on the distal end of 7XL around Xpsr680, Xpsr687 andXwg380. The RFLP markers of psr680, psr687 and wg380 werecosegregated with the BYDV resistance respectively and could be used formolecular assisted selection (MAS) in wheat breeding program for BYDVresistance.  相似文献   
125.
Molecular marker analysis can be an effective tool when searching for new fire blight resistance donors. It can speed up the breeding process as well, even though many of the available markers linked to fire blight resistance QTLs have not yet been tested by screening a large number of cultivars. The aim of this study was to search for alternate sources of the three major QTLs of fire blight resistance; FBF7, FB_MR5 and FB_E, as well as to test the efficiency of some markers linked to minor QTLs. Altogether, nine primer pairs were used on 77 genotypes including new Hungarian cultivars and old apple cultivars from the Carpathian basin. Several marker alleles of FB resistance QTLs have been detected in the screened genotypes, most importantly the alleles coupling with FB_MR5 in the old cultivars ‘Kéresi muskotály’, ‘Szabadkai szercsika’ and ‘Batul’. We propose these cultivars as the first available resistance donors of FB_MR5 instead of the crabapple Malus × robusta 5. The results also bring new information regarding the resistance alleles of new Hungarian cultivars and selections.  相似文献   
126.
In the common bean crop in Brazil, the requirement of the value for cultivation and use trials is that these experiments must be conducted over two years in three locations per region. Information in regard to the necessary number of years to ensure precision in cultivar recommendation and the influence of evaluated years in the estimation of the GE interaction are still scarce. Using grain yield of five check varieties assessed over 11 years in three sowing seasons per year, the aims of this study are as follows: to measure the relative contribution of the GE interaction, evaluating the implication of the number of years in the estimates of the GE interaction, and infer how many years are needed to ensure precision in cultivar recommendation. For instances, analysis of variance was carried out involving all environments and also combinations of years. The results showed that the GE interaction was greater than all other cross‐effects involving lines. The use of at least two years allows good coincidence in cultivar recommendation compared to the whole period. Increasing the evaluation time is a good strategy, especially when it is difficult to grow three different sowing seasons.  相似文献   
127.
GA1,3,4,7酶联免疫检测法(ELISA)的建立   总被引:11,自引:1,他引:11  
用碳二亚胺法将赤霉素A4与卵清蛋白连接,形成GA4-OVA复合物用于包板,利用GA4-Me与GA4-0VA对兔抗GA4-PAbs竞争结合反应,建立了GA1,3,4,7间接酶闻免疫检测法。其灵敏度,检测范围和最小检测样品量分别为45pg,0.2-200ng和50-500mg,样品的平均回收率为97%,批内和批间的变异系数分别为4.2%和4.8%。  相似文献   
128.
The 7DL.7Ag translocation from Lophopyrum elongatum that carries Lr19, a leaf rust resistance gene, was found to be associated with a significant increase in grain yield under irrigated, disease‐free conditions, but a generally lower yield under moisture stress conditions. These studies, however, involved a limited number of genetic recipients and environments, and the effect of the translocation on physiological traits was not considered. We examined the translocation effect in six different recipient genotypes and under five environmental conditions, including drought and heat stress. The increase in grain yield under irrigated conditions was associated with a higher rate of biomass production in the 7DL.7Ag lines and may be attributed to higher sink strength. Effect of the translocation on physiological traits was noted only under heat stress and was not associated with difference in yield. Under moisture stress conditions, 7DL.7Ag lines yielded less than their corresponding recipients, possibly because of a longer growing cycle. It is concluded that the effect of the 7DL. 7Ag translocation may very much depend on the phenological adaptation of the recipient genotype and the translocation may be useful for enhancing yield, mainly under favourable conditions.  相似文献   
129.
夏播大豆品种的生育期特性与农艺性状的关系分析   总被引:2,自引:0,他引:2  
从 339个大豆品种中选取生育期小于 1 0 0d的 1 0 3个品种进行生育期结构特性与农艺性状的分析。结果表明 :①R1最长的为华北品种 ,最短的为外国品种 ;②R7最长的为东北品种 ,最短的为南方品种 ;③R1与生育前期即营养生长阶段 ,高纬地区长于低纬地区 ;R7与生育后期即生殖生长阶段 ,低纬地区长于高纬地区 ;④R1、生育前期长的品种 ,单株荚数、单株粒数多 ,株高较高 ;R7、生育后期长的品种 ,百粒重高 ;⑤筛选出一批对光温不敏感的品种  相似文献   
130.
The present study was aimed to investigate the possible interaction of the standardized extract of Acorus calamus (AC) with Cytochrome P450 enzyme, quantitative determination of the α-asarone in the AC rhizome was performed by RP-HPLC method. In vitro interaction of the plant extract was evaluated by CYP450-carbon monoxide complex (CYP450-CO) assay. Effect on individual isoforms such as CYP3A4 and CYP2D6 isozymes were analyzed through fluorescence product formation and respective IC50 values were determined. CYP450-CO assay showed moderate interaction potential. Extract showed higher IC50 values (46.84 ± 1.83-32.99 ± 2.21 μg/ml) comparing to the standard inhibitors and lower IC50 value than α-asarone (65.16 ± 2.37-42.15 ± 2.45 μg/ml).  相似文献   
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