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排序方式: 共有206条查询结果,搜索用时 46 毫秒
1.
肾上腺皮质肿瘤(Adrenocortical Tumor,ACT)是一种常见的肿瘤,存在于人体的内分泌系统中,并且是引发肾上腺皮质癌(Adrcnocortical Carcinoma,ACC)进而导致死亡的主要原因.经典的"Weiss系统"在诊断明确性上存在种种无法解决的问题,但随着科技水平的发展,人们开始探索新的途径来鉴别ACT的良恶性,于是开始有了影像学和分子生物学技术等特异性的检查方法,从而进一步增强了诊断的明确性.现通过对比的方式,探究肾上腺皮质肿瘤(Adrenocortical Tumor,ACT)影像学检查和分子生物学技术检查的结果,从而能更准确地鉴别其良恶性. 相似文献
2.
应用反义RNA技术抑制甜瓜成熟过程中内源乙烯的合成,从而培育耐贮运品种是解决甜瓜延熟保鲜难题的可行新方法。根据GenBank中甜瓜、黄瓜ACC合成酶基因氨基酸保守序列设计引物,从成熟的薄皮甜瓜(齐甜1号)果肉组织中提取总RNA,经RT-PCR扩增得到约0.7kb的ACC合成酶cDNA片段,将其克隆到质粒载体pGEM-TEasy中,测序表明,该基因为777bp,编码258个氨基酸;从番茄(东农706)叶片组织中提取总DNA,经PCR扩增得到约2.2kb的E8基因片段,将其克隆到质粒载体pGEM-TEasy中,测序表明,该基因为2192bp;以pCAM2301为起始植物表达载体,pCAM-GT为中间载体,成功构建了果实特异启动子(E8)调控薄皮甜瓜ACC合成酶cDNA反义表达载体,采用冻融法将其转入根癌农杆菌LBA4404,得到了完整的Ti质粒表达载体系统。 相似文献
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4.
LU Xin-xing YANG Jin-li WANG Hai-rong WANG Gui-chao GAO Ai-wu ZHANG Li-min HOU Xian-zhi 《中国畜牧兽医》2015,42(12):3202-3209
To study the effect of nutrient restriction and compensation on weight,serum indexes and gene expression of chest fat adipokine in Mongolian lamb,thirty male lambs were randomly divided into control group (20.26 kg± 3.63 kg) and feed restricted group (21.29 kg±3.00 kg).The experiment lasted for 120 days,including 60 days for feed restriction and 60 days for compensatory feed.At the end of each stage,five lambs from each group were slaughtered and chest fat was collected.Serum concentration of triglycerides,non-esterified fatty acids (NEFA),total cholesterol were measured.Quantitative Real-time PCR were used to determine Adiponectin,Visfatin,PPAR-γ and ACC genes expression.The results showed that:①The lamb body weight of restricted group kept maintain level and that of control group showed a increase tendency.During the compensatory period,the average daily gain (ADG) of restricted group was significantly higher than control group (P< 0.05).②During the restriction period,serum triglycerides concentration of lambs in restricted group was significantly decreased at day 30 and 60 (P< 0.05),and NEFA concentration was significantly increased at day 30 (P< 0.05).After 60 days of nutritional compensation,all serum parameters we tested were not significantly different between restrict group and control group (P >0.05).③During the restriction period,PPAR-γ and ACC gene expression in restricted group were significantly lower than that of control group (P< 0.05),while no significant differences were found during the compensation period (P>0.05).Adiponectin and Visfatin genes expression in chest fat was not significantly changed throughout the experiment (P >0.05).We could know that nutritional restriction reduced fatty acid synthesis and adipocyte differentiation ability,adipose tissue was mobilized energy metabolism,and total cholesterol was recoveried growth on the compensation.However,the ACC and PPAR-γ genes in restricted group were significantly decreased with the body weight increased rapidly during the compensatory stage.Adiponectin and Visfatin were not significantly different between restricted and compensatory stages. 相似文献
5.
Altaf QadirErrol W. Hewett Peter G. LongDavid R. Dilley 《Postharvest Biology and Technology》2011,62(3):314-318
Premature softening and tissue senescence occur in kiwifruit infected with Botrytis cinerea. While ethylene production is enhanced in infected fruit and B. cinerea produces ethylene on defined media in vitro the source of ethylene in this pathosystem is unclear. Ethylene production by B. cinerea was enhanced when methionine or ∝-keto-methylthiobutyric acid (KMBA) was added to a defined (modified Pratts) medium. Although 1-aminocyclopropane-1-carboxylic acid (ACC) did not stimulate ethylene production, ∝-aminooxyacetic acid (AOA) was inhibitory suggesting a role for a pyridoxal phosphate mediated enzyme reaction down stream from the methionine/KMBA stimulated ethylene biosynthetic pathway. Cobalt chloride (Co2+) was inhibitory, but after a 4-d lag period ethylene production from B. cinerea cultures containing methionine and Co2+ reached the same level as those without Co2+. [U 14C] methionine was converted to 14C-ethylene with high efficiency indicating that it is a direct precursor, while [2,3 14C]-ACC did not yield radioactively labelled ethylene. These results suggest that the ethylene biosynthetic pathway in B. cinerea does not involve ACC as a precursor and that the enzyme responsible for synthesising ethylene is similar to, but different from, ACC oxidase from higher plants. The ethylene biosynthetic pathway in B. cinerea is yet to be determined. 相似文献
6.
间隙升温处理对芒果内源多胺和ACC含量的影响 总被引:8,自引:1,他引:8
紫花芒果在冷害低温中贮藏,对其进行间隙升温处理。结果表明:芒果发唾冷害以后,其内源SPD和SPM含量显著增加,但内源PUT和CAD含量的变化不显著;冷害还导致了ACC的累积。间隙升温处理显著地减轻了芒果的冷害,延迟了多胺及ACC含量的上升。 相似文献
7.
经反应红120亲和层析纯化的小麦胆色素原脱氨酶(Porphobilinogen deaminase,PBGD,EC.4,3,1,8),在SDS-PAGE和IEF-PAGE上均显示一条带,表明已PBGD纯化至均一,它的亚基分子量36KD,pI为4.8。酶活性染色呈一条带,表明无同工酶存在。PAGE显示两条带,证明小麦幼苗中存在酶与底物结合的中间物。脲梯度电泳呈现之字形,在4mol/L的脲浓度下可使酶 相似文献
8.
反义ACC氧化酶基因的导入对番茄乙烯生成的抑制作用 总被引:14,自引:0,他引:14
将反向克隆的ACC氧化酶基因通过Ti质粒导入到番茄基因组中,转基因番茄植株叶片和果实中ACC氧化酶活性和乙烯产生速率均受到显著抑制,显示出反义基因能抑制靶基因(ACC氧化酶)的表达。子代抗性标记基因的分离结果表明呈单基因遗传。 相似文献
9.
黄河蜜甜瓜1-氨基环丙烷1-羧酸合成酶基因片段的克隆和反义载体的构建 总被引:3,自引:0,他引:3
从伤诱导的黄河蜜甜瓜(Cucumismelocv.Huanghemi)成熟果实的中果皮组织中分离总RNA,经反转录和PCR扩增得到974bp的cDNA片段,克隆到质粒载体pGEM-3zf,经测序与Genbank中甜瓜1-氨基环丙烷1-羧酸合成酶(1-amino-cyclopropane-1-carboxylieacidsynthase,ACS)基因同源性为99%。克隆片段经双酶切消化,反向插入到植物表达载体pBI121的35S启动子和NOS终止子之间,构建成ACS基因的反义表达载体。 相似文献
10.
PG,ACC,乙烯对番茄果实成熟的影响 总被引:14,自引:0,他引:14
番茄果实在成熟过程中硬度下降迅速,PG活性急剧上升,表现出显著的负相关;用ACC和乙烯利处理绿熟期果实,结果乙烯促进了正常番茄和alc番茄果实成熟进程,其PG活性也升高,而外源乙烯和ACC不影响nor基因突变体果实的成熟进程。ACC和PG无直接关系。 相似文献