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41.
 本研究对利用真空渗入法获得的转bar基因及pinⅡ基因菜薹,进行了外源基因的遗传及表达情况分析。结果表明通过该方法获得的转基因植株,外源基因能够稳定遗传。bar基因在 代的分离大部分符合孟德尔遗传规律,但也有不符合的群体;pin II基因在 代中稳定表达,但各个株系之间的表达水平差异较大,因而各个株系的抗虫效果也具有显著差异,即使具有相同外源基因拷贝数的各个株系,其PIN I/蛋白表达量和抗虫效果也具有显著差异。  相似文献   
42.
AIM: To investigate inhibition of K562 cell growth by antisense drug targeted VEGF mRNA. METHODS: X7, 20-mer antisense sequences were selected, synthesized and modified with phosphorothioate. The drug was transfected into K562 cells in the present of lipofection. Cell growth was assayed by trypan blue dye exclusion assay and MTT. The level of VEGF protein in the media was determined by ELISA. The morphology of apoptotic cells were observed by Giemsa staining, and the propotion of apoptotic cells was detected by flow cytometry. RESULTS: The antisense drug inhibited growth of K562 and downregulated expression of VEGF protein significantly, compared with Scrambed control group and showed dose-dependent relation. Signs of apoptosis of K562 cells were not observed. CONCLUSION: Inhibition of K562 cell proliferation, but not cells apoptosis induction is the mechanism of inhibing growth of K562 cells by antisense drug targeted VEGF mRNA. At same time, VEGF has function of promoting K562 cell proliferation, and VEGF mRNA may be a new target attached by drugs.  相似文献   
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LI Shu-guo  ZENG Qiu-tang 《园艺学报》2004,20(12):2232-2235
AIM: This study was designed to investigate the secretion of VEGF and its receptor (flt-1 or flk-1/KDR) protein by cultured bovine thoracic aortic endothelial cells treated with various insulin concentrations. METHODS: Endothelial cells was isolated from bovine thoracic aorta, and cultured in serum-free medium, then incubated with different insulin concentrations (30 mU/L, 300 mU/L, 3 000 mU/L). The level of VEGF and its receptor (flt-1 or flk-1/KDR) protein were detected by immunohistochemical staining. RESULTS: As compared with no insulin group, the expression of VEGF protein in low insulin concentration (30 mU/L and 300 mU/L) groups were significantly increased (P<0.01). The expression of VEGF protein in high insulin concentration (3 000 mU/L) group was significantly decreased (P<0.05). Howerer, no difference of the expression of VEGF receptor (flt-1 or flk-1/KDR) protein among all groups (P>0.05) was observed. CONCLUSION: Low concentration insulin up-regulates the VEGF protein expression while high concentration insulin down-regulates the VEGF protein expression in bovine thoracic aortic endothelial cells, but insulin had no directly effect on the VEGF receptor (flt-1 or flk-1/KDR) protein expression in bovine thoracic aortic endothelial cells.  相似文献   
45.
AIM: To study the expression of vascular endothelial growth factor (VEGF) in inflammatory mucosa of lacrimal sac. METHODS: Immunohistochemical S-P method was used to examine the expression of VEGF in the mocusa from 12 patients with chronic dacryocystitis and 8 volunteers. RESULTS: The positive rates of VEGF expression in different parts of the mocusa were: basal lamina: 44.3%±7.6%; surface epithelium: 16.9%±4.6%; connective tissue: 15.2%±4.9%, all normal mocusa of 8 cases were negative. There was a significant difference between the two groups (P<0.01), a significant difference among each part of the chronic inflammatory mocusa of lacrimal sac. CONCLUSION: VEGF may play an important role in hyperplasia of inflammatory mucosa of lacrimal sac.  相似文献   
46.
AIM: The effects of YIGU capsule on proliferation and IGF-I mRNA protein expressions in osteoblasts were studied. METHODS: (1) Forty 12-month old Sprague-Dawley female rats were divided randomly into four groups (YIGU capsule high dose group, medium dose group and low dose group; saline group), the drug-containing serum and control serum were prepared. (2) The new-born Sprague-Dawley rat osteoblasts were cultured with different YIGU capsule drug-containing serum at different concentrations and different exposure time. MTT method was used to observe proliferation of osteoblasts. (3) RT-PCR method was used to measure the relative IGF-I mRNA levels and ELISA method was used to measure IGF-I secretion at different exposure time. (4) ELISA method was used to measure IGF-I secretion at different exposure time. RESULTS: (1) Proliferation of osteoblasts was more than the control groups after 48, 72 and 96 h, respectively (P<0.01); (2) The relative IGF-I mRNA levels and IGF-I protein expression were higher than those in control group after 48, 72 and 96 h, respectively (P<0.01 or P<0.05). CONCLUSIONS: It was suggested that YIGU capsule drug-containing serum promoted proliferation, IGF-I mRNA and protein expression. These results may be parts of the mechanisms of YIGU capsule to prevent and treat osteoporosis.  相似文献   
47.
SUN Fen-yong  PAN Qiu-hui  HONG An 《园艺学报》2004,20(12):2316-2319
AIM: To further investigate the role of PKARⅠβ in the growth-promoting effects of shuang long Jiegu pill (SLJGP), a Chinese medicine, on cultured osteoblasts. METHODS: pcDNA- antiPKARⅠβ, a recombinant expressing the antisense sequence of PKARⅠβ, was constructed and transformed HFOB1.19 by lipofectin. MTT was undertaken to assess the cell growth with the treatment of high dosage of SLJGP containing serum. RESULTS: Antisense gene blocked the growth-promoting effects of SLJGP containing serum on HFOB1.19. CONCLUSION: The function of SLJGP is closely related to cAMP-dependent protein kinase A.  相似文献   
48.
应用提取的鼠脂肪细胞膜分别免疫羊和鸡 ,所产生的抗血清用于 Wistar大鼠被动免疫。实验 1: 组腹腔注射羊正常血清 , 组腹腔注射羊抗鼠脂肪细胞膜抗血清 ,剂量均为 1m L /只 ,连续注射 4 d。结果表明 ,羊抗鼠脂肪细胞膜抗血清免疫促进了大鼠体增重 ,降低了体脂沉积 ,与对照组相比 ,7周末体重增加 6 .35 % (P<0 .0 5 ) ,饲料摄入增加6 .85 % (P<0 .0 1) ,料重比 (F/G)提高 4 5 .0 0 % (P<0 .0 5 ) ;肾周、附睾、网膜脂肪垫重量分别降低 2 3.92 % (P<0 .0 5 )、34.4 5 % (P<0 .0 5 )、0 .98% ,脂肪总量降低 2 0 .92 %。实验 2 :1组腹腔注射鸡正常血清 ,2组腹腔注射鸡抗鼠脂肪细胞膜抗血清 ,剂量均为 1m L/只 ,连续注射 4 d。结果表明 ,鸡抗鼠脂肪细胞膜抗血清免疫对大鼠的生长发育产生了不利影响 ,7周末 ,免疫大鼠平均体重较对照组减少 4 0 g(P<0 .0 5 ) ,饲料摄入显著降低 (P<0 .0 1) ;对体脂的沉积和血液中 TG和 FFA的影响没有规律 ,且无统计学意义  相似文献   
49.
运用免疫组织化学超敏 SP法对山羊胎儿脊髓发育中神经生长因子 (nerve growth factor,NGF)及其高亲和力受体 Tr KA的表达及其功能进行了系统的研究和探讨。结果显示 ,山羊胎儿脊髓灰质中存在 NGF及其受体 Tr KA,于 6周龄胚就可检测到 ,随胚龄增加 ,其表达范围及免疫反应着色程度逐渐增强。 NGF主要分布于腹角和背角的神经细胞 ,反应产物主要定位于胞质和突起 ;Tr KA的分布主要以腹角及胶状质为主 ,反应产物主要定位于胞核 ,后期胞质及突起也可见到阳性反应。在山羊胎儿脊髓白质中也可观察到 NGF及 Tr KA免疫阳性反应 ,其发育后期更为显著 ,阳性反应主要分布于神经胶质细胞核、神经纤维的轴索及雪旺氏细胞。结果提示 ,NGF不仅对交感和感觉神经元的发育起作用 ,而且还与腹角运动神经元的发育有关  相似文献   
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