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71.
【目的】克隆玉米Zea mays淀粉合成酶SSⅡa启动子,并分析其功能,为进一步研究和应用SSⅡa启动子奠定基础。【方法】通过NCBI上公布的玉米基因组序列,在网站Maize GDB上BLAST查找到SSⅡa 5'侧翼序列,利用PCR方法从玉米B73中克隆SSⅡa启动子;通过Plant Care在线分析启动子顺式作用元件,用特异性引物分别克隆出长度为1 407、867、633、483和365 bp的片段,与植物表达载体p CAMBIA3301连接,构建5种5'缺失体的植物表达载体,命名为P1、P2、P3、P4和P5。用农杆菌介导法转化拟南芥Arabidopsis thaliana,获得转基因拟南芥。【结果】以玉米B73基因组DNA为模板,用特异性引物SSⅡa F/SSⅡaR进行扩增,得到2 526 bp序列;除草剂筛选的阳性拟南芥植株PCR验证均检测出gus基因;GUS组织化学分析表明,5种类型启动子构建的表达载体在成熟期叶片、果荚中均显蓝色;gus基因定量分析表明,成熟期5种转基因拟南芥叶片中,gus基因表达量P1最高,其他基本一致;种子中gus基因表达量P1和P2相近,且高于P3、P4和P5。【结论】成功克隆玉米SSⅡa启动子;构建的5种SSⅡa启动子缺失体表达载体在转基因拟南芥中均具有活性,长度为1 407 bp(P1)和867 bp(P2)的启动子具有胚乳特异性。 相似文献
72.
Sung PJ Li GY Su YD Lin MR Chang YC Kung TH Lin CS Chen YH Su JH Lu MC Kuo J Weng CF Hwang TL 《Marine drugs》2010,8(10):2639-2646
Two new 12-hydroxybriarane diterpenoids, designated as excavatoids O (1) and P (2), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1 and 2 were established on the basis of extensive spectral data analysis. Excavatoid P (2) is the first metabolite which possesses a 6β -chlorine atom in briarane analogues. 相似文献
73.
南疆不同品种绵羊MSTN基因克隆及其组织表达谱分析 总被引:2,自引:0,他引:2
本研究旨在对山区型和田羊、平原型和田羊、卡拉库尔羊的MSTN基因进行组织表达谱分析。参考GenBank上(登录号:NM_001009428.1)绵羊MSTN基因序列设计引物,采用RT-PCR技术克隆绵羊MSTN基因序列,进行组织表达谱分析。结果表明:MSTN基因在各品种绵羊不同组织中表达的差异较大,MSTN在各品种绵羊的肌肉、肾脏和脾脏中都有表达,其中肌肉中表达量最高,其次是肾脏和脾脏;MSTN在山区型、平原型和田羊的心脏中表达丰度较低,而在卡拉库尔羊心脏中则几乎无表达;MSTN在山区型、平原型和田羊的肝脏中几乎无表达,而在卡拉库尔羊肝脏中则有一定量表达;MSTN在山区型和田羊、平原型和田羊与卡拉库尔羊的肺脏中则都无表达。 相似文献
74.
Essential regulation of CNS angiogenesis by the orphan G protein-coupled receptor GPR124 总被引:1,自引:0,他引:1
Kuhnert F Mancuso MR Shamloo A Wang HT Choksi V Florek M Su H Fruttiger M Young WL Heilshorn SC Kuo CJ 《Science (New York, N.Y.)》2010,330(6006):985-989
The orphan G protein-coupled receptor (GPCR) GPR124/tumor endothelial marker 5 is highly expressed in central nervous system (CNS) endothelium. Here, we show that complete null or endothelial-specific GPR124 deletion resulted in embryonic lethality from CNS-specific angiogenesis arrest in forebrain and neural tube. Conversely, GPR124 overexpression throughout all adult vascular beds produced CNS-specific hyperproliferative vascular malformations. In vivo, GPR124 functioned cell-autonomously in endothelium to regulate sprouting, migration, and developmental expression of the blood-brain barrier marker Glut1, whereas in vitro, GPR124 mediated Cdc42-dependent directional migration to forebrain-derived, vascular endothelial growth factor-independent cues. Our results demonstrate CNS-specific angiogenesis regulation by an endothelial receptor and illuminate functions of the poorly understood adhesion GPCR subfamily. Further, the functional tropism of GPR124 marks this receptor as a therapeutic target for CNS-related vascular pathologies. 相似文献
75.
KN Galvo M Frajblat WR Butler SB Brittin CL Guard RO Gilbert 《Reproduction in domestic animals》2010,45(5):e207-e211
Our objectives were to determine the effects of early ovulation on fertility and uterine health of dairy cows. Four hundred and forty‐five Holstein cows (185 primiparous and 260 multiparous) from five herds were used. Blood samples were collected at 21, 35 and 49 days in milk (DIM) and cows were considered to be cyclic at 21 DIM (Cyc21) if serum progesterone (P4) concentration was above 1 ng/ml, cyclic by 49 DIM (Cyc49) if P4 concentration was above 1 ng/ml at 35 or 49 DIM, or not cyclic (NotCyc) if P4 concentration was below 1 ng/ml at all sample times. Endometrial cytology for diagnosis of subclinical endometritis was examined at 49 DIM in a subset of 414 cows. Cows in the group Cyc21 had increased hazard of insemination, for the first service, compared with cows in Cyc49 [hazard ratio (HR) = 1.40; 95% CI = 1.10–1.79; p = 0.006] and NotCyc (HR = 2.07; 95% CI = 1.52–2.82; p < 0.001). Cows in the Cyc49 group also had increased hazard of insemination compared with cows in the NotCyc group (HR = 1.47; 95% CI = 1.13–1.93; p = 0.005). Median days to insemination were, respectively, 71, 76 and 96 for cows in Cyc21, Cyc49 and NotCyc groups. Cows in Cyc21 had greater first service pregnancy per AI than Cyc49 [38.6 vs 28.1%; adjusted odds ratio (AOR) = 1.67; 95% CI = 1.01–2.75; p = 0.04] and NotCyc (38.6 vs 23.6%; AOR = 2.08; 95% CI = 1.08–4.00; p = 0.03). Pregnancy per AI was similar in Cyc49 and NotCyc cows (28.1 vs 23.6%; AOR = 1.25; 95% CI = 0.70–2.24; p = 0.45). Cows in Cyc21 had increased hazard of pregnancy up to 300 DIM compared with Cyc49 (HR = 1.52; 95% CI = 1.17–1.96; p = 0.002) and NotCyc (HR = 1.98; 95% CI = 1.41–2.78; p < 0.001). Cows in Cyc49 tended to have increased hazard of pregnancy compared with NotCyc (HR = 1.31; 95% CI = 0.96–1.77; p = 0.09). Median days to pregnancy were, respectively, 103, 147 and 173 for cows in Cyc21, Cyc49 and NotCyc groups. Cows in the Cyc21 group had decreased prevalence of subclinical endometritis compared with cows in the NotCyc group (29.9 vs 43.7%; AOR = 0.53; 95% CI = 0.29–0.97; p = 0.04); however, the prevalence did not differ from the Cyc49 group (29.9 vs 39.1%; AOR = 0.68; 95% CI = 0.41–1.14; p = 0.15). Cyc49 cows had similar prevalence of subclinical endometritis compared with NotCyc cows (AOR = 0.77; 95% CI = 0.46–1.29; p = 0.32). Early postpartum ovulation was associated with improved uterine health and fertility. 相似文献
76.
77.
Effects of Vibrio harveyi on plasma clotting protein (coagulogen) of white shrimp Litopenaeus vannamei 下载免费PDF全文
Wen‐Hsiao Chuang Ping‐Chung Liu Yu‐Chun Chien Yu‐Chen Wu Kuo‐Kau Lee 《Aquaculture Research》2016,47(11):3464-3476
Blood clotting exhibits various important functions, including the prevention of body fluid loss and invasion of pathogens in shrimp. The effects of pathogenic Vibrio harveyi on plasma of white shrimp (Litopenaeus vannamei) in vitro and in vivo were investigated in this study. The clotting protein (coagulogen) in plasma of white shrimp pre‐incubated with extracellular products (ECP) of V. harveyi was found apparently decreased and fast‐migrated in crossed immunoelectrophoresis (CIE) gels. In addition, the coagulogen had been degraded to many low molecular‐weight protein bands in plasma pre‐incubated with ECP on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) gels. When pre‐challenged with bacterial cells and ECP of V. harveyi, the white shrimp began to die at about 30 and 16 h respectively. Moreover, plasma coagulogen was decreased more obvious in shrimp challenged with ECP than that with bacterial cells as visualized in CIE gels, and total plasma protein in both group of shrimp were all decreased. Haemolymph withdrawn from moribund shrimp pre‐challenged with V. harveyi or its ECP was observed unclottable. However, the addition of clotting factors (transglutaminase and/or Ca2+) to these unclottable plasma could apparently promote their re‐clotting ability as jelly‐like solid observed in microtubes. The recovery of clotting ability of plasma from moribund shrimp was due to the reformation of coagulogen (200 kDa) after adding the two clotting factors as shown on CIE and SDS‐PAGE gels. The present results suggest that the infection of V. harveyi in white shrimp may not only degrade coagulogen but also influence the presence of transglutaminase and Ca2+ ion. 相似文献
78.
Hsu YL Chen CY Lin IP Tsai EM Kuo PL Hou MF 《Journal of agricultural and food chemistry》2012,60(3):852-861
4-Shogaol is one of the phytoconstituents isolated from dried red ginger, which is commercially available to consumers. Some active constituents from ginger have been found to have anti-inflammatory and antioxidant effects, but studies on 4-shogaol have been relatively rare. This is the first report describing the antimetastasis activities of 4-shogaol and the possible mechanisms. This study determined that 4-shogaol inhibits the migration and invasion of MDA-MB-231 and causes mesenchymal-epithelial transition (MET). In addition, 4-shogaol suppresses the activation of NF-κB and cell migration and invasion induced by TNF-α. Furthermore, 4-shogaol has been shown to inhibit the phosphorylation of IκB and the translocation of NF-κB/Snail in MDA-MB-231. This study shows that RKIP, an inhibitory molecule of IKK, is up-regulated after 4-shogaol treatment and prolongs the inhibitory effects of 4-shogaol. Inhibition of RKIP by shRNA transfection significantly decreases the inhibitory effect of 4-shogaol on the NF-κB/Snail pathway, together with cell migration and invasion, whereas overexpression of Snail suppresses 4-shogaol-mediated metastasis inhibition and E-cadherin upregulation. Finally, the animal model revealed that 4-shogaol effectively inhibits metastasis of MDA-MB-231 in mice. This study demonstrates that 4-shogaol may be a novel anticancer agent for the the treatment of metastasis in breast cancer. 相似文献
79.
PD Duh ZT Chen SW Lee TP Lin YT Wang WJ Yen LF Kuo HL Chu 《Journal of agricultural and food chemistry》2012,60(32):7866-7872
Antiproliferative activity and apoptosis induction of ethyl acetate of Eucalyptus citriodora resin (EAEER), and its major bioactive compound in melanoma B16F10 cells were investigated. 6-[1-(p-Hydroxy-phenyl)ethyl]-7-O-methyl aromadendrin (HEMA), a flavanol derivative, was isolated from EAEER and identified on the basis of its mass and NMR spectra. The results from MTT assay showed high antiproliferative effects of EAEER and HEMA on B16F10 cells. Moreover, EAEER- and HEMA-induced cell apoptosis was association with the decrease in the mitochondrial transmembrane potentials (Δψ(m)), increase in Bax/Bcl-2 ratio, and activation of caspase-3. Cells treated with EAEER and HEMA generated intracellular reactive oxygen species (ROS) and nitric oxide (NO), indicating that ROS and RNS play important roles in the induction of apoptosis in B16F10 cells. Taken together, EAEER and its major bioactive compound, HEMA, inhibited the proliferation of B16F10 cells via apoptosis and may be a potential antimelanoma agent. 相似文献
80.
Computerized color separation system for printed fabrics by using backward-propagation neural network 总被引:1,自引:0,他引:1
Textile production must be coupled with hi-tech assistant system to save cost of labor, material, time. Therefore color quality control is one very important step in any textiles, however excellent the fabric material itself is, if it lacks good color, then it may still result in dull sale. Therefore, this paper proposes a printed fabrics computerized color separation system based on backward-propagation neural network, whose primary function is to separate rich color of printed fabrics pattern so as to reduce time-consuming manual color separation color matching of current players. What it adopted was RGB color space, expressed in red, green, and blue. Analyze color features of printed fabrics, use gene algorithm to find sub-image with same color distribution as original image of printed fabrics yet smaller area, for later color separation algorithm use. In terms of color separation algorithm, this paper relied on supervised backward-propagation neural network to conduct color separation of printed fabrics RGB sub-image, and utilized PANTONE® standard color ticket to do color matching, so as to realize accurate color separation. 相似文献