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21.
An agglutination test based on colored silica nanoparticles (colored SiNps) was established to detect serotypes of Pseudomonas aeruginosa. Monodisperse colored SiNps were used as agglutination test carriers. The colored SiNps were prepared through reverse microemulsion with reactive dyes, sensitized with 11 kinds of mono-specific antibodies against P. aeruginosa, and denoted as IgG-colored SiNps. Eleven kinds of IgG-colored SiNps were individually mixed with P. aeruginosa on a glass slide. Different serotypes of P. aeruginosa could be identified by agglutination test with evident agglutination. The P. aeruginosa could be detected in a range from 3.6 × 105 to 3.6 × 1012 cfu mL?1. This new agglutination test was confirmed to be a specific, sensitive, fast, easy-to-perform, and cost-efficient tool for the routine diagnosis of P. aeruginosa.  相似文献   
22.
Eight experiments were carried out in Denmark to determine the yield loss of spring barley due to Cirsium arvense in farmers' fields and to suggest and evaluate a novel approach for quantifying C. arvense infestation in large plots. Literature about the competitive ability of C. arvense is old, scattered and inconclusive, and existing models for estimating crop yield loss are based on data from North America. This study showed that C. arvense coverage could be quantified from unmanned aerial vehicle imagery using a manual image analysis procedure. This gave similar results as scoring the coverage. Yield loss of spring barley due to C. arvense infestation assessed at harvest was given by Y = 100·(1−exp(−0.00170·X)) where Y is the percentage of crop yield loss and X is the percentage of C. arvense coverage. The yield loss was much lower than estimates from models that have been developed in North America. It is speculated that the main reason for this is the later emergence of C. arvense than the crop due to lower soil temperatures in spring. Grain moisture increased linearly with C. arvense coverage: M = 0.0310·X where M is the proportional (%) increase in grain moisture and X is the proportion (%) of C. arvense coverage. Automated image analysis procedures are needed to estimate C. arvense coverage on field scales, and further experiments are needed to reveal whether the low competitive ability of C. arvense found in this study is representative for Northern Europe.  相似文献   
23.
红星302 是以抗病、耐低温弱光材料01-61 为母本,以01-23 为父本育成的串番茄一代杂种,无限生长类型,果实串收,果色亮红,果实椭圆形,酸甜适口,品质佳,VC 含量为364 mg · kg-1,可滴定酸0.44%,可溶性糖4.25%,平均单果质量30.79 g,硬度为11.40×105 Pa。单株结果数约为53个,产量4 900 kg ·( 667 m2-1 左右,高抗蕨叶病毒病、青枯病,适宜河北地区冬季日光温室和早春保护地栽培。  相似文献   
24.
从视觉艺术的角度研究食用菌品牌形象的设计。通过讨论品牌名称、标志物和文字等食用菌品牌视觉要素,提出了食用菌品牌形象的视觉艺术价值设计原则。食用菌品牌形象的视觉艺术价值体现在品牌设计的多个方面,创新的视觉艺术能让食用菌品牌形象真正体现艺术的价值。  相似文献   
25.
基于CNN的小麦籽粒完整性图像检测系统   总被引:3,自引:0,他引:3  
为了快速、准确识别小麦籽粒的完整粒和破损粒,设计了基于卷积神经网络(CNN)的小麦籽粒完整性图像检测系统,并成功应用于实际检测中。采集完整粒和破损粒两类小麦籽粒图像,对图像进行分割、滤波等处理后,建立单粒小麦的图像数据库和形态特征数据库。采用LeNet-5、AlexNet、VGG-16和ResNet-34等4种典型卷积神经网络建立小麦籽粒完整性识别模型,并与SVM和BP神经网络所建模型进行对比。结果表明,SVM和BP神经网络所建模型的验证集识别准确率最高为92. 25%; 4种卷积神经网络模型明显优于两种传统模型,其中,识别性能最佳的AlexNet的测试集识别准确率为98. 02%,识别速率为0. 827 ms/粒。基于AlexNet模型设计了小麦籽粒完整性图像检测系统,检测结果显示,100粒小麦的检测时间为26. 3 s,其中,图像采集过程平均用时21. 2 s,图像处理与识别过程平均用时为5. 1 s,平均识别准确率为96. 67%。  相似文献   
26.
AIM:To explore the effect of pidotimod on the renal function in IgA nephropathy (IgAN) rat model, and to further study whether this effect is related to the inhibition of inflammatory response. METHODS:The SD rats (n=36) were randomly divided into control group, IgAN model group, IgAN with prednisone treatment group and IgAN with pidotimod treatment group, with 9 rats in each group. The IgAN model was induced by consecutive oral administration of bovine gamma globulin (BGG) for 8 weeks followed by injection of BGG through tail vein for 3 d. After the IgAN model was established, the drug was continuously used for 4 weeks. At the end of the treatment, the urine protein, serum creatinine and blood urea nitrogen were examined by an automated analyzer. IgA deposition in the renal tissues was observed by immunofluorescence staining. The mRNA expression levels of renal fibrosis markers transforming growth factor-β1 (TGF-β1) and fibronectin 1 in the renal tissues were detected by RT-qPCR. The mRNA and protein levels of pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-6 in the renal tissues were determined by RT-qPCR and Western blot, respectively. RESULTS:No significant difference of the body weight was observed in different groups. Compared with control group, the content of urine protein, serum creatinine and blood urea nitrogen were significantly increased (P<0.01), whereas those were reversed by pidotimod treatment. The results of immunofluorescence staining showed that pidotimod inhibited IgA deposition in the IgAN rats. Pitomod treatment inhibited the mRNA expression levels of renal fibrosis markers TGF-β1 and fibronectin 1, and the mRNA and protein levels of pro-inflammatory cytokines IL-1β and IL-6 in the renal tissues of IgAN rats. CONCLUSION:Pidotimod alleviates IgAN progression in rats by inhibition of inflammatory response.  相似文献   
27.
AIM: To investigate the effects of astragaloside IV (AS-IV) on chemokine receptor 4 (CXCR4) and stromal cell-derived factor 1α (SDF-1α) in endothelial progenitor cells (EPCs) and its mechanism. METHODS: Rat bone marrow-derived EPCs were cultured in vitro. The proliferation, adhesion, migration, apoptosis and tube formation capacity of EPCs treated with AS-IV and AMD3100, a specific blocker of CXCR4, were observed. The effects of AS-IV on the expression of SDF-1α/CXCR4 at mRNA and protein levels and the protein level of p-CXCR4 in the EPCs were determined. RESULTS: AS-IV significantly enhanced the proliferation, adhesion, migration and tube formation abilities of EPCs, reduced the apoptosis of EPCs, and up-regulated the mRNA and protein expression of SDF-1α and CXCR4 and the p-CXCR4 protein level in the EPCs. On the other hand, AMD3100 blocked the up-regulating effect of AS-IV on the mRNA and protein expression of CXCR4 and the p-CXCR4 protein level in the EPCs, but did not affect the effect of AS-IV on the expression of SDF-1α. CONCLUSION: AS-IV might enhance the biological function of EPCs by regulating the expression of SDF-1α/CXCR in EPCs.  相似文献   
28.
AIM: To explore the role of DNA methylation of microRNA-30a-5p(miR-30a-5p) promoter region in hepatic injury. METHODS: Four-week-old normal mice and cystathionine β-synthase (CBS) single gene knockout mice were used and divided into normal (CBS+/+, n=12) group and single gene knockout (CBS+/-, n=12) group, and the mice were fed with high methionine diet for 8 weeks. HL-7702 hepatic cells were routinely cultured in vitro and divided into control group, homocysteine (Hcy) group and Hcy+5-azacytidne (AZC) group. Serum Hcy, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured by automatic biochemical analyzer. The levels of ALT and AST in the cells culture medium were determined by the microplate method. Hepatic injury in the mice were observed with HE staining. Cell viability staining was used to measure the viability of hepatocytes. RT-qPCR was used to detect the expression of miR-30a-5p in the liver tissues and hepatocytes. The correlation between the expression of miR-30a-5p and serum ALT and AST levels was analyzed by Pearson correlation analysis. DNA methylation level of miR-30a-5p promoter region in the liver tissues and hepatocytes was detected by nested landing methylation-specific PCR (nMS-PCR). RESULTS: Compared with the CBS+/+ mice, the serum levels of Hcy, ALT and AST in the CBS+/- mice were significantly increased (P < 0.05). HE staining showed the hepatocyte swelling and nuclear fragmentation and dissolution. The expression level of miR-30a-5p in the liver tissues was decreased (P < 0.01). Besides, the expression level of miR-30a-5p in the mice was negatively correlated with serum ALT and AST levels (r2=0.4557, P=0.0003, r2=0.4626, P=0.0003), and the DNA methylation of miR-30a-5p promoter region was increased (P < 0.01). In the HL-7702 cells, compared with control group,the ALT and AST levels were increased in Hcy group (P < 0.05, P < 0.01), and the cell viability was remarkablely decreased. DNA methylation of miR-30a-5p promoter region was increased (P < 0.01), which decreased after treated the cells with AZC (P < 0.05), while the expression level of miR-30a-5p in the cells was increased (P < 0.05). CONCLUSION: Hypermethylation of miR-30a-5p promoter region may play an important role in hepatic injury.  相似文献   
29.
寿研梦扬是由母本CSVHPM1407001和父本CSVHPF1407002配制而成的羊角椒一代杂种。植株长势旺盛,连续坐果能力强;果实长羊角形,果长25~30 cm,果肩宽3~4 cm;青熟果黄绿色,老熟果红色;外表光亮,商品性好,耐贮运;单果质量100 g左右,辣味浓,宜鲜食;田间对病毒病、炭疽病和疫病的抗性强于对照喜洋洋。保护地栽培鲜椒产量可达12 840 kg·(667 m~2)~(-1)左右。适宜山东、河北等地区早春、秋延保护地种植。  相似文献   
30.
黑甜糯玉米新品种黑甜糯639的选育   总被引:1,自引:0,他引:1  
黑甜糯639是以糯玉米自交系HNF为母本,以甜玉米自交系D91为父本配制而成的黑甜糯玉米一代杂种。生育期为91 d(天),株高263 cm,穗位151 cm,雄穗主轴与分枝角度中等,一级分枝18~23个,果穗筒型,籽粒黑紫色,甜糯籽粒比例为1∶3,籽粒可溶性糖含量为12.5%,支链淀粉占总淀粉含量的98.1%,口感佳。高抗丝黑穗病、茎腐病、大斑病,抗穗腐病和矮花叶病,平均每667 m~2鲜穗产量900 kg左右。适宜在山西省鲜食糯玉米主产区种植。  相似文献   
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