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991.
黄金梨引自韩国,经过10 a的系统观察、区域试验、综合性状鉴定和棚架栽培技术研究,该品种在辽宁地区表现良好,果实近圆形,平均单果重356.2 g,果皮黄色,果皮薄,肉质细嫩、多汁,果肉白色,石细胞少,果心小,可食率高,味甜,可溶性固形物12.1%,总糖8.39%,总酸0.16%,Vc 5.62mg/100g,硬度8.68kg/cm2,品质极上;果实9月上旬成熟,较耐贮运,常温下可贮藏20~30d.幼树2a见果,4 a丰产.在辽宁熊岳以南地区发展前途广阔.  相似文献   
992.
在有机管理方式下,茶翅蝽Halyomorpha halys (St(.a)l),已上升为苹果园主要害虫,成为防治的重要难题之一.2007年在北京昌平地区有机苹果园中,通过枝干调查、杀虫灯诱集对茶翅蝽的发生情况进行调查,明确其发生及迁移规律,为茶翅蝽的控制提供依据.在控制策略上,以重点消灭第一代成虫为主,灵活运用各种植保措施.  相似文献   
993.
高山反季节栽培珍稀菇试验   总被引:1,自引:0,他引:1  
杏鲍菇、真姬菇、鸡腿菇3个珍稀菇均属中低温型菌类,市场前景看好。通过高山反季节栽培珍稀菇试验得出,利用高海拔地区的自然条件,可选择3种菇的最佳栽培时间及烂菇、病虫害发生等的气象调控管理办法,为山区建立珍稀菇无公害生产基地,提供了科学的气象依据和技术借鉴。  相似文献   
994.
试验旨在研究中国荷斯坦奶牛真核生物翻译延伸因子1D(eukaryotic translation elongation factor 1 delta,EEF1D)基因的多态性及其与产奶性状的相关性。利用Sequenom MassARRAY SNP分型技术对宁夏地区1 252头中国荷斯坦奶牛EEF1D基因的多态性进行了检测,并对其多态位点不同基因型和组合基因型与产奶性状进行了关联分析。结果显示,EEF1D基因的5'侧翼区存在2个SNPs位点,即EEF1D-1和EEF1D-3;经检测发现,EEF1D-1存在2种基因型,EEF1D-3存在3种基因型。χ2检验表明,中国荷斯坦奶牛在EEF1D-1位点偏离Hardy-Weinberg平衡状态(P < 0.05),在EEF1D-3位点未偏离Hardy-Weinberg平衡状态(P > 0.05);EEF1D-1和EEF1D-3位点多态信息含量(PIC)分别为0.10和0.28,分别呈现低度多态和中度多态。在试验群体中,EEF1D-1位点对乳脂率和乳蛋白率性状的效应均达到极显著水平(P<0.01),对305 d产奶量性状的效应达到显著水平(P<0.05);EEF1D-3位点对305 d产奶量、乳脂率和乳蛋白率性状的效应均达到极显著水平(P<0.01);EEF1D基因的优势基因型组合GG-AG和GG-GG个体乳脂率均显著高于GG-AA组合个体(P<0.05)。说明EEF1D基因可以作为影响中国荷斯坦奶牛产奶性状的候选基因用于标记辅助选择。  相似文献   
995.
AIM: To establish and validate a novel model of cultured cells for imitating intermittent hypoxia. METHODS: In a chamber with experiment cabin and simulated air control cabin, the frequency and duration of the intermittent hypoxia model according to the time of hypoxia and reoxygenation were evaluated. The A549 cells were randomly divided into 7 groups, named as control (Con) group, 6 h intermittent hypoxia (6IH) group, 9 h intermittent hypoxia (9IH) group, 6 h simulated air control (6AC) group, 9 h simulated air control (9AC) group, 4 h sustained hypoxia (4SH) group, 6 h sustained hypoxia (6SH) group, respectively. When the model was established, the cellular morphology was observed under inverted microscope. The mRNA expression of hypoxia-inducible factor (HIF)-1α was detected by real-time PCR. The protein expression of HIF-1α was analyzed by immunohistochemistry. RESULTS: The intermittent hypoxia cycle (5% O2 60 min-20% O2 30 min for 6 cycles) was established. The damaged A549 cells were observed in 6IH group, 9IH group and 6SH group. Compared with 6IH group, the expression of HIF-1α at mRNA and protein levels was significantly increased in 9IH group (P<0.05). The expression of HIF-1α at mRNA and protein levels in 6IH group and 9IH group was higher than that in 4SH group and 6SH group, respectively (P<0.05). No significant difference among the control group, 6AC group and 9AC group was found. CONCLUSION: The model (5% O2 60 min-20% O2 30 min for 6 cycles) can simulate the pathological process of obstructive sleep apnea hypopnea syndrome. This model is suitable for studying intermittent hypoxia in adherent cells.  相似文献   
996.
AIM: To explore the effect of atorvastatin on the expression of α-SMA and TGF-β1 in the adventitia of ApoE-/- mice with atherosclerosis, and to investigate the underlying mechanism of atorvastatin therapy. METHODS: Male ApoE-/- mice (n=40) at 6-weeks of age were used to establish the atherosclerosis model by feeding with high fat diet. The mice were randomly divided into model group and atorvastatin group. In atorvastatin group, the mice were lavaged with atorvastatin at dose of 20 mg·kg-1·d-1. The mice in model group were given normal saline. C57BL/6 mice of the same age served as control group, feeding with ordinary food. The mice were respectively sacrificed at the time points of 10 and 15 weeks after feeding with different diets. The ascending aorta was removed for serial sectioning. Some sections were performed with Movat staining in order to observe the morphological changes of the tissues, and to measure the relative atherosclerotic plaque area and the thickness of the adventitia. Some sections were stained with Sirius red to identify the collagen synthesis. Immunohistochemistry assay was prepared to observe the expression of α-SMA and TGF-β1 in the adventitia at different time points. The expression of TGF-β1 at mRNA and protein levels in the thoracoabdominal aorta was measured by RT-qPCR and Western blot.RESULTS: Compared with model group, the formation of plaque in atorvastatin group significantly descended. Meanwhile the adventitial thickness and collagen synthesis also decreased. The results of immunohistochemical staining showed that compared with 10 weeks-model group, α-SMA and TGF-β1 in 15 weeks-model group was increased. The expression of α-SMA and TGF-β1 in atorvastatin group decreased significantly compared with model group. The expression of TGF-β1 at mRNA and protein levels in model group were higher than those in control group. They decreased in atorvastatin group compared with model group. Compared with 10 weeks-model group, the mRNA and protein of TGF-β1 in 15 weeks-model group were increased.CONCLUSION: Atorvastatin modulates adventitial fibroblast phenotype differentiation by suppressing expression of TGF-β1 and intervenes atherosclerotic development in ApoE-/- mice.  相似文献   
997.
DREB2A基因对苜蓿遗传转化的研究   总被引:11,自引:4,他引:7  
盛慧  朱延明  李杰  柏锡  才华 《草业科学》2007,24(3):40-45
以黑龙江紫花苜蓿Medicago sativa主栽品种:肇东苜蓿、敖汉苜蓿、公农1号和公农2号为受体材料,系统地探讨了除菌剂种类和浓度以及卡那霉素筛选浓度等,建立了高效的苜蓿再生体系和遗传转化体系;分别构建了由诱导型启动子rd29A和组成型启动子E12调控的DREB2A基因的2个植物表达载体pB2A29A和pB2AE12;采用农杆菌介导法进行遗传转化,获得大量转基因抗性植株并进行了分子生物学(PCR和Southern blot)检测.结果表明,DREB2A基因已整合到苜蓿基因组中.  相似文献   
998.
板栗产业发展现状、问题与对策   总被引:9,自引:0,他引:9  
板栗属壳斗科栗属坚果类植物,其组织成分中含有大量淀粉,还含有蛋白质、脂肪、B族维生素等多种营养素,并具多种药用价值,素有“干果之王“‘铁杆庄稼“之美称.中国板栗品质优良,其显著特点是品位独特、色泽艳丽,对病虫害具有较强的抵抗能力.尤其在欧美和日本栗遭受栗疫病、墨水病的毁灭性打击下,我国板栗深受消费者的青睐.发展板栗产业,既有利于开发山区资源,发挥山区优势,增加山区人民的经济收入,又有利于丰富果品种类,满足市场和人们生活的需要.……  相似文献   
999.
就世界可可近半个世纪的价格变化,主要生产国的生产、贸易和主要消费国的消费进口等情况进行了较详尽的综述  相似文献   
1000.
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