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91.
CsFAD7基因转化烟草的研究 总被引:1,自引:0,他引:1
以"革新一号"烟草种子为试材,采用根癌农杆菌介导的烟草叶盘转化法将来源于黄瓜的脂肪酸去饱和酶基因(FAD7)转入烟草,并在附加300mg/L氨苄青霉素(Amp)的MS+0.1mg/L NAA+1.0mg/L 6-BA的培养基上诱导植株分化,再生芽在附加300mg/L Amp和100mg/L卡那霉素(Kan)的MS培养基上生根,获得再生植株。结果表明:Kan阳性植株经PCR检测筛选,得到转基因阳性植株,证明异源FAD基因已转入烟草基因组中。T1代经PCR-South-ern检测证明转化基因可以遗传;转基因烟草在低温胁迫下生长较好,叶绿素荧光参数F0值下降不大,Fv/Fm值保持较高,表现了对低温的耐受能力,脂肪酸分析表明,该基因可以使烟草叶片的亚麻酸含量比例升高。 相似文献
92.
Immunohistochemical characterization of canine prostatic carcinoma and correlation with castration status and castration time 总被引:2,自引:0,他引:2
K. U. Sorenmo M. Goldschmidt F. Shofer C. Goldkamp J. Ferracone 《Veterinary and comparative oncology》2003,1(1):48-56
The purpose of this study was to characterize canine prostate cancer using immunohistochemical staining specific for acinar and urothelial/ductal tissue and correlate these results with the dogs' castration status/castration time. Seventy dogs with prostate cancer were included, 71% were castrated and 29% were intact. Compared with an age‐matched control population, castrated dogs were at increased risk of prostate cancer, odds ratio 3.9. Immunohistochemical staining was performed on 58 cases. Forty‐six of the 58 stained positive for cytokeratin 7 (CK 7) (ductal/urothelial origin) and one of the 58 stained positive for prostate‐specific antigen. Dogs with CK 7‐positive tumours were younger when castrated than dogs with CK 7‐negative tumours, 2 versus 7 years (P = 0.03); dogs castrated at ≤2 years of age were more likely to be CK 7‐positive (P = 0.009). These results show that most canine prostatic carcinomas are of ductal/urothelial, androgen‐independent origin. This is consistent with the epidemiological findings, showing increased risk in castrated dogs. Canine prostate cancer may, therefore, not be a realistic model for the human disease. 相似文献
93.
Seedling crops of gazania, geranium, marigold, mimulus, pansy, verbena and vinca were grown to 60% anthesis in three greenhouse temperature regimes: (a) 26 °C day/6 ± 3 °C night (LT), with a 16.5 °C mean daily temperature (MDT), (b) 26 °C day/17 ± 4 °C night, with a 21 °C MDT, and (c) variable day/night temperatures in response to heating and cooling by a phase change material energy storage module (PCM) with an 8 ± 2 °C night and a 16 °C MDT. Crops bloomed from 2 to 17 days earlier in the 26 °C/17 °C greenhouse. The morphological characteristics of all cultivars of gazania, mimulus, pansy and verbena, geranium and vinca were similar regardless of greenhouse temperature regime. Marigold diploid and triploid cultivars and mimulus were morphologically more variable than the other bedding plant species. Crops grown in the PCM and LT greenhouses had virtually identical morphological characteristics and bloomed in about the same number of days. Plant height was not affected by DIF environments in the greenhouses. The PCM and LT greenhouses had a similar MDT, but the distribution of numbers of hours of mean daily temperatures was different. 相似文献
94.
本文介绍了在现代教育思想和教育理论的指导下,结合教学实践,对中等职业学校技工学校机械类焊接专业的专业课<焊工工艺学)CA1课件的设计和制作进行了分析和研究,利用Macromedia公司的多媒体制作软件Authorware7,02设计和制作<焊工工艺学>多媒体教学课件的过程. 相似文献
95.
血清4型鸭疫里默氏杆菌在我国的发现及其病原特性研究 总被引:9,自引:3,他引:6
本文首次报道了血清4型鸭疫里默氏杆菌在中国的发现。1994年1月至2000年10月,从全国28个省(市、自治区)不同代次(原种、祖代、父母代和商品代)的5-90日龄患有典型鸭疫里默氏杆菌病的病死鸭分离到146株血清4型的鸭疫里默氏杆菌。对其病原学特性进行研究的结果表明,血清4型的鸭疫里默氏杆菌在我国鸭群感染分布的范围极广,分离菌株对雏鸭具有很强的致病性,对小鼠无致病性,各在分离菌株表现出一致的形态特征和非常相似的生理生化特性;各地分离菌株耐药谱很广,但对头孢类药物(如头孢拉啶、头孢克洛等)和利福平却普遍高度敏感。用分离菌株制备的灭活疫苗免疫雏鸭具有良好的免疫原性。 相似文献
96.
Savlík M Polácková L Szotáková B Lamka J Velík J Skálová L 《Research in veterinary science》2007,83(1):20-26
Basal activities of certain pheasant hepatic and intestinal biotransformation enzymes and modulation of their activities by anthelmintics flubendazole (FLBZ) and mebendazole (MBZ) were investigated in subcellular fractions that were prepared from liver and small intestine of control and FLBZ or MBZ treated birds. Several oxidation, reduction and conjugation enzyme activities were assessed. In the liver, treatment of pheasants by FLBZ or MBZ caused very slight or no changes in monooxygenase activities and conjugation enzymes. More significative changes were detected in small intestine. Metyrapone and daunorubicin reductase activities were increased by both substances in the liver. This is the first evidence that certain benzimidazoles modulate reductases of carbonyl group. With respect to the relatively slight extent of the changes caused by FLBZ or MBZ we can assume that repeated administration of therapeutic doses of both FLBZ and MBZ has probably no serious influence on pheasant biotransformation enzyme system. 相似文献
97.
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
98.
AIM: To observe the neuritogenic actions of botulinum neurotoxin serotype A heavy chain (BoNT/A HC) on cultured Neuro-2a cells and to investigate the related signaling mechanisms for the effect of BoNT/A HC. METHODS: Neuro-2a cells were treated with different doses of BoNT/A HC (0.01, 0.1, 1 and 10 nmol/L), and then the cells were harvested at 24 h, 48 h and 72 h of BoNT/A HC exposure for detecting the neurite length and the percen-tage of the cells with neuronal processes by immunofluorescence staining. The most efficient dose of BoNT/A HC was chosen for exposure to Neuro-2a cells as the above. Whole cell protein was harvested at different time points for detecting the protein levels of phosphorylated ERK1/2 (p-ERK1/2) and phosphorylated Akt (p-Akt) by Western blot. RESULTS: Low doses of BoNT/A HC stimulated the neurite outgrowth, and increased the percentage of the cells with neurites compared with the negative controls (P<0.05), especially in the group with 1 nmol/L of BoNT/A HC treatment. Meanwhile, the phosphorylation of ERK1/2 and Akt was increased after treated with BoNT/A HC. There was an increasing tendency for the phosphorylation of ERK1/2 after the exposure of the cells to BoNT/A HC. The obvious increase in p-ERK1/2 was seen from 60 min to 5 h with 1 nmol/L of BoNT/A HC treatment (P< 0.05), and the increased protein level of p-Akt was mainly observed at 15 min and 60 min (P<0.05). CONCLUSION: BoNT/A HC stimulates the neuritogenesis. The neuritogenic mechanism of BoNT/A HC on Neuro-2a cells might be realized by activation of the phosphorylation of ERK1/2 and Akt. 相似文献
99.
100.
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
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