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1.
本文是基于意法半导体(ST)新推出的一款高性能Cortex TM-M4内核的ARM芯片STM32F407ZGT6,进行的双CAN总线设计。在开发过程中采用了ST提供的可视化图形界面开发工具STM32Cube进行底层驱动的配置,简化了设计工作。但由于该工具链接的固件库函数存在传递参数错误,使得CAN总线无法接收数据,本文对该库函数进行了更正。  相似文献   
2.
强继业  郭华春 《种子》2003,(4):29-30
应用3 2 P研究“合作 88”马铃薯对磷素营养的吸收和分布规律 ,结果显示 :马铃薯对磷素营养的吸收率随植株的生长而增加。吸收率与栽培生长时间呈显著正相关。磷素主要分布为茎 >根 >叶 ,随生育期茎中含量相对增加 ,而叶中含量相对减少 ,根的不变。  相似文献   
3.
本文介绍了ISPM32号标准框架下基于有害生物风险的商品分类管理的总体思路和我国现行的植物检疫措施,比较了我国现行检疫措施与ISPM32号标准的区别,提出了基于检疫风险的植物产品动态分级管理模型,以期为建立适合我国国情的植物检疫分类管理体系,推进植物检疫措施规范化、标准化、国际化提供参考。  相似文献   
4.
秦芋32号(原代号:康0102-5)是2000年以秦芋30号作母本,89-1优系作父本,有性杂交获得实生种子,经育种圃、鉴定圃选育而成。2011年3月申报国家农作物品种审定委员会待审,2011年10月通过审定。2007~2009年参加国家级马铃薯品种中晚熟西南组繁种及区域试验;2010年国家西南组生产试验平均产量1 443 kg/667 m2,比对照米拉增产12.5%。块茎干物质含量18.5%、淀粉含量11.8%,Vc含量14.2 mg/100 g,还原糖含量0.29%,粗蛋白含量2.1%。抗病性接种鉴定:中抗PVX和PVY,抗晚疫病。  相似文献   
5.
Pseudomonas fluorescens strain PfG32R, a potential biocontrol agent against soilborne pathogens, frequently loses its antifungal activity and ability to produce enzymes. To characterize genetically the instability of these bacterial functions, we analyzed gacS and gacA genes of PfG32R and three spontaneous mutants of PfG32R (NR1, NR9, and ASW6), which had lost their ability to produce proteases and antifungal activities. The gacS and gacA sequences of PfG32R had 77%–89% and 78%–87% homology, respectively, with several known gacS and gacA homologues. All three spontaneous mutants were subjected to complementation analysis. Introduction of clones containing an intact gacS of PfG32R and another P. fluorescens strain Pf-5 as well as strain tea632 of P. syringae pv. theae complemented all three mutants restoring protease and antifungal activities, indicating a mutation in gacS. In sequencing analysis, the mutants had a deletion or change in amino acids in the conserved sensor kinase domains of GacS. The three mutants maintained both their antibacterial activity against Ralstonia solanacearum and Clavibacter michiganensis ssp. michiganensis and siderophore production, indicating that they are not controlled by the GacS/GacA system. The sequences reported in this article have been deposited in the DDBJ database under accession numbers AB219364 and AB219365.  相似文献   
6.
羊痘研究概况   总被引:9,自引:2,他引:9  
羊痘病毒基因组庞大,约有150 kb,包括中间编码区和两端相同的反向末端重复序列;绵羊痘病毒和山羊痘病毒基因组彼此十分相似,约有96%的核苷酸完全相同.p32蛋白是目前世界各地分离鉴定的所有羊痘病毒株共有的且特异性很强的结构蛋白,在诊断和预防方面具有重要的应用价值.虽然羊疸从临床症状和宿主特异性上很客易做出诊断,但进一步的实验室确诊还是必要的,现已有多种检测方法和诊断试剂.控制该病最有效的方法是使用疫苗对易感动物进行免疫接种.文章从病原学、诊断和预防控制等方面对羊痘进行综述.  相似文献   
7.
我国家具业的发展状况与思考   总被引:2,自引:0,他引:2  
介绍了我国家具业的发展,对我国家具业的市场容量、产品结构、所用材料及现有问题进行了分析和思考,并提出了解决办法。  相似文献   
8.
Root distribution of the wild jack tree (Artocarpus hirsutus) was determined by selective placement of 32P at various depths and lateral distances from the tree, in Kerala, India. In eight-and-a-half-year-old trees growing on a lateritic site, absorption of 32P from a lateral distance of 75 cm and 30 cm depth was much greater than from 150 and 225 cm lateral distance and 60 and 90 cm depth. Root activity declined with increasing depth and lateral distance. Most of the physiologically active roots were concentrated within a radius of 75 cm and 30 cm depth, although the tap root might reach even deeper. Possibly, surface accumulation of feeder roots may cause considerable overlap of the tree and crop root zones in intercropping situations. However, as the tree roots seldom extend beyond 2.25 m laterally from the trunk, the effect of overlapping root zones and the associated competitive effects may not be a serious problem for intercropping during the first few years (<10 years after planting) of tree growth.  相似文献   
9.
为了开发出一种可行的羊痘基因疫苗,尝试用羊P32基因与CD58基因建立共表达载体.试验根据GenBank中收录的羊痘病毒(GPV)P32和羊CD58基因组序列,设计了扩增GPV P32基因和CD58基因的特异性引物,运用PCR技术从GPV中扩增出P32基因,从羊的外周血中扩增出CD58基因,并将其分别克隆到pMD18-T载体,测序正确.将P32基因去掉后端疏水区一段与CD58基因先后克隆至载体pBudCE4.1,并转化大肠埃希菌JM109,提取质粒通过酶切鉴定和测序正确,且读码框正确.说明成功获得了真核共表达质粒pBudCE4.1/CD58/P32.  相似文献   
10.
Repeated injections of salmon pituitary extract (20 mg per fish per week) induced vitellogenesis in feminized, cultivated Japanese eels (Anguilla japonica). Oocytes were attained at the migratory nucleus stage after 11 or 12 injections. Addition of 17,20-dihydroxy-4-pregnen-3-one (DHP) into the incubation medium induced germinal vesicle breakdown (GVBD) in the oocytes at the migratory nucleus stage. An injection of DHP (2 µg g-1 BW), given 24h after an injection of salmon pituitary extract (20 mg fish-1), succeeded in inducing maturation and ovulation in females which contained occytes at the migratory nucleus stage. Most fish ovulated 15–18h following the DHP injection. Eggs that were ovulated within 15h after the DHP injection showed high fertility and hatchability, but eggs ovulated 18 or 21h after the DHP injection, showed considerably lower fertility and hatchability. A delay between ovulation and stripping of the eggs rapidly decreased both the fertility and hatchability within 6–9h after ovulation, indicating that artificial fertilization must be carried out immediately after ovulation. Repeated injections of human chorionic gonadotropin (hCG) at a concentration of 1 IU g-1 BW week-1 induced spermatogenesis, spermiation, and the acquisition of potential for sperm motility in cultivated males. Most males spermiated after the fifth or sixth injection of hCG, and the milt weight gradually increased and remained constant (1–2 g) from the 11th to 31th injection. Sperm motility peaked 24h after each weekly injection, and decreased from the 3rd day after the injection. Potassium ions are an essential constituent for the maintenance of motility in the eel spermatozoa. Artificial seminal plasma containing 15.2 mM KCl is applicable as a milt diluent. Using these techniques developed for female and male eels, we have succeeded in obtaining many fertilized eggs from cultivated eels.  相似文献   
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