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101.
李正丽  陈松 《园艺学报》2017,44(8):1623-1624
‘老农908’是F1代鲜食辣椒新品种。果长15.28 cm,果宽1.63 cm,果实线形,青熟果绿色,老熟果鲜红色,味辛辣,平均单果鲜质量14.14 g,平均鲜椒产量25 878.3 kg·hm~(-2)。抗逆性强,结果性强,适合贵州辣椒种植区及省外气候条件相似的地区栽培。  相似文献   
102.
The present study investigated the effects of simulated transport stress on morphology and gene expression in the small intestine of laboratory rats. Sprague Dawley rats were subjected to 35 °C and 0.1×g on a constant temperature shaker for physiological, biochemical, morphological and microarray analysis before and after treatment. The treatment induced obvious stress responses with significant decreases in body weight (< 0.01), increases in rectal temperature, serum corticosterone (CORT), serum glucose (GLU), creatine kinase (CK) and lactate dehydrogenase (LDH) levels (< 0.01), as well as expression of Hsp27/70/90 mRNA (< 0.05; < 0.01). The rat jejunum was severely damaged and apoptotic after mimicking transport stress, which may mainly be related to cell death, oxidation reduction and hormone imbalance determined by microarray analysis. The bioinformatics analysis from the present study would provide insight into the potential mechanisms underlying transport stress-induced injury in the rat small intestine.  相似文献   
103.
We analyzed the nucleotide sequences of the G-L (glycoprotein-large protein) intergenic non-coding region of 33 strains of the rabies virus (RABV) isolated in South Korea in 1998-2010 and compared the sequences with those of previously reported non-Korean strains. The similarities of the nucleotide sequences of the G-L region among all Korean RABV isolates ranged from 97.1 to 100%. Based on the phylogenetic analysis of the G-L region, the Korean RABV isolates were classified into three distinct subgroups with high similarity and were most closely related to the non-Korean NeiMeng1025C isolate, which was isolated from a rabid raccoon dog in eastern China, suggesting that the Korean RABV isolates originate from a rabid raccoon dog in northeastern Asia. Our results indicated that G-L region, as a useful phylogenetic indicator, is equivalent to the nucleoprotein (N) or glycoprotein (G) gene for study of RABV molecular epidemiology and that the Korean RABV isolates showing a few substitutions in the G-L region are continuously circulating in South Korea.  相似文献   
104.
Xu Q  Song X  Xu L  Yan R  Shah MA  Li X 《Veterinary parasitology》2008,156(3-4):319-323
A fusion DNA vaccine co-expressed Eimeria tenella TA4 and chicken IL-2 (chIL-2) was constructed and its efficacy against E. tenella challenge was observed. TA4 gene of E. tenella and chIL-2 gene were cloned into expression vector pcDNA3.1 and pcDNA4.0c in different forms, producing vaccines pcDNA3.1-TA4-IL-2, pcDNA3.1-TA4 and pcDNA4.0c-IL-2. The expression of aim genes in vivo was detected by RT-PCR and western blot. Animal experiment was carried out to evaluate the immune efficacy of the vaccines. Results indicated these DNA vaccines were successfully constructed and the antigen genes could be expressed effectively in vivo. The animal experimental results showed that DNA vaccines could obviously alleviate cecal lesions, body weight loss and increase oocyst decrease ratio. The ACI of pcDNA3.0-TA4-IL-2 group was 192, higher than that of pcDNA3.1-TA4 group. The results suggested that TA4 was an effective candidate antigen for vaccine and co-expression of cytokine with antigen was an alternative method to enhance DNA vaccine immunity.  相似文献   
105.
两种一步法RNA提取试剂的比较   总被引:2,自引:0,他引:2  
RNA的提取在生物医学研究和临床检测上应用广泛。本文分别用进口Invitrogen公司生产的以及我们自己研制的一步法RNA提取试剂,提取大肠杆菌RNA、鸡肌肉组织RNA和尿囊液RNA,通过核酸电泳和荧光定量RT-PCR进行比较。结果表明用我们自己研制的和进口的试剂提取的RNA都不含有DNA;这些RNA都可以作为模板进行RT-PCR检测,并且在数量上相互之间没有明显差异。说明我们自己研制的一步法RNA提取试剂可以取代进口试剂。此外,本文还讨论了此类试剂一些评定方法。  相似文献   
106.
In this study, we tried to optimize the porcine semen extender conditions to maximize the differences between live X chromosome-bearing (X) spermatozoa and to Y chromosome-bearing (Y) spermatozoa without a decline in the fertility rate at different pH conditions during storage. We observed the viability of X and Y boar spermatozoa in acidic (pH 6.2), original (pH 7.2), and alkaline condition (pH 8.2) for 5 days to investigate the effect of storage conditions on the X to Y spermatozoa ratio. The functional parameters of spermatozoa were also examined to evaluate sperm quality. Sperm motility was preserved at pH 7.2 and pH 6.2 for 3 days, while sperm motility at pH 8.2 decreased significantly after 2 days. Non-capacitated spermatozoa increased while capacitated spermatozoa decreased during storage. Sperm viability decreased significantly duration-dependent under all pH conditions, but there was no significant difference during storage at pH 6.2 and 7.2. The X: Y ratio of live spermatozoa in acidic condition was maximized (1.2:1) without affecting the sperm function and fertility-related protein expression after 2 days compared to original conditions. Moreover, insemination of sows using acidic extender increased the number of female pups on days 1 and 2 of preservation. These results indicate that the production of female offspring may increase when acidic BTS is used for 2 days without affecting the success rate of AI. Above all, this method is simple and economical compared to other methods.  相似文献   
107.
家蚕GH18家族几丁质酶的系统进化和BmChi的时期表达分析   总被引:2,自引:0,他引:2  
昆虫GH18家族几丁质酶主要参与昆虫蜕皮、细胞增殖和免疫等生理过程。为了系统开展家蚕GH18家族基因的研究,通过多物种几丁质酶的系统进化分析鉴定了8个家蚕GH18家族成员,并根据含有糖苷水解酶18(Glyco_18)催化结构域和几丁质结合结构域的不同将其分为6类,其中,各物种的CHT5具有典型几丁质酶结构。家蚕GH18家族成员中,BmChiR-1具有5个Glyco_18催化结构域和6个几丁质结合结构域,其它7个成员均只有1个Glyco_18催化结构域,BmCHT12还有1个ChitnaseA_N端结构域。8个家蚕GH18家族成员的基因分布在7条染色体上。通过半定量RT-PCR调查家蚕CHT5基因Bm-Chi在家蚕各发育时期的转录表达模式,该基因在蜕皮、化蛹、羽化等发育时期均有高水平表达,推测BmChi在蚕体旧表皮几丁质的降解过程中发挥重要作用。  相似文献   
108.
本文简要介绍了涕灭威的活性及其作用机制,详细分析了其在国内外登记管理、食品中涕灭威残留及其风险评估、土壤中涕灭威归趋及其对水体的影响研究进展.  相似文献   
109.
Liu F  Liu H  Jia Q  Wu X  Guo X  Zhang S  Song F  Dong H 《Phytopathology》2006,96(10):1052-1059
ABSTRACT HpaG(Xooc), produced by Xanthomonas oryzae pv. oryzicola, is a member of harpin group of proteins that stimulate plant growth, hypersensitive cell death (HCD), and pathogen defense. The protein contains two copies of the glycine-rich motif (GRM), a characteristic of harpins, and a cysteine, which is absent in other harpins. Genetic modification generated the pro-tein mutants HpaG(Xooc)MG (MG) by deleting GRMs and HpaG(Xooc)C47T (C47T) by replacing cysteine with threonine. When applied to tobacco plants, C47T and MG were 1.2- and 1.7-fold stronger, respectively, than HpaG(Xooc) in inducing HCD, which occurred consistently with expression of the marker genes hin1 and hsr203. The proteins markedly alleviated infection of tobacco by Tobacco mosaic virus and Arabidopsis and tomato by Pseudomonas syringae. Treating tobacco plants with HpaG(Xooc), C47T, and MG decreased the viral infection by 58, 81, and 92%, respectively. In Arabidopsis and tomato plants treated with HpaG(Xooc), C47T, or MG, P. syringae multiplication was inhibited; bacterial population multiplied in 5 days in these plants were ca. 160-, 1,260-, or 15,860-fold smaller than that in control plants. So pathogen defense was induced in both plants. Defense-related genes Chia5, NPR1, and PR-1a were expressed consistently with resistance. In response to HpaG(Xooc), C47T, and MG, aerial parts and roots of tomato plants increased growth by 15 and 53%, 25 and 77%, and 46 and 106%, relative to controls. The expansin gene, EXP2, involved in the cell expansion and plant growth was expressed coordinately with plant growth promotion. These results suggest that the presence of GRM and cysteine in HpaG(Xooc) represses the effects of the protein in plants.  相似文献   
110.
小火蚁是中国大陆新发现的重要外来入侵害虫, 目前对该虫的传入来源和在我国的适生区范围尚不明确?为明确我国小火蚁适生区范围, 有效防控该虫在我国的扩散和蔓延, 本研究通过该虫全球已有的分布数据, 采用最大熵模型对其适生区进行了预测?研究表明, 最大熵模型预测小火蚁适生区精度较高?预测结果显示, 我国小火蚁的潜在适生区主要分布于南方, 其中, 高适生区分布在台湾?海南?云南南部边境?广西西南局部?福建西南部?广东南部及其沿海地区?预测结果与该物种现有地理范围的生态条件一致?年降水量对小火蚁的适生性影响最大, 理论年降水量为2 040 mm时小火蚁分布的概率最高?随着全球气候变暖, 未来我国小火蚁的适生区有向北扩大的趋势, 但主要适生区还是以南方为主?  相似文献   
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