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1.
除草剂谷友对谷田杂草的除草效果及对谷子安全性的影响   总被引:12,自引:0,他引:12  
以冀谷19为试材,研究了44%谷友(单嘧.扑灭)WP对谷田杂草的田间防效及对谷子安全性的影响。结果表明:44%谷友最佳使用剂量为1 800 g/hm2。在该剂量下,除草效果较好,且对谷子生产安全,谷子产量与人工锄草基本相同,但较50%扑灭津WP(药剂对照)增产显著。  相似文献   
2.
Specific harmful organisms whether singly or associated with plants shall not be introduced into the European Community. All activities which would involve these organisms are not allowed. The authorities can make under defined requirements an exception for activities for trial or scientific purposes and for work on varietal selections. The responsible body has to determine conditions which must be satisfied in the case of introductions, movements or activities, in order to ensure that there is no risk of harmful organism spreading. The legal basis is the Commission directive 95/44/EC transferred into German legislation by the Pflanzenbeschauverordnung.  相似文献   
3.
The use of specific immunoglobulin heavy chain variable region (VH) genes has been associated with increased patient survival in human B-cell lymphomas (hBCL). Given the similarity of human and canine BCL (cBCL) in morphology and clinical treatment, we examined the choice of VH in cBCL and determined whether VH gene selection was a distinct feature associated with survival time in dogs. VH gene selection and mutational status in 52 cBCL, including 29 diffuse large B-cell lymphomas (cDLBCL, the most common subtype of cBCL), were analyzed by comparison with the 80 published canine germline VH gene sequences. We further examined the prognostic impact of the subgroups defined by these features on canine survival. We found that VH1-44 was preferentially expressed in the majority of the 52 cBCLs (60%) as well as in the majority of the cDLBCL subset (59%). VH1-44 gene expression was associated with a statistically better overall survival (p = 0.039) in cBCL patients, as well as in the cDLBCL subset of patients (p = 0.038). These findings suggest that VH gene selection in cBCL is not random and may therefore have functional implications for cBCL lymphomagenesis, in addition to being a useful prognostic biomarker.  相似文献   
4.
利用“川麦42”ד川农16”构建的重组自交系群体(127个株系),对抽穗期、株高、穗长、千粒重等10个农艺性状进行了研究,结果表明,各性状在RIL群体中呈连续变异,分布频率基本符合正态分布,同时存在双向超亲分离现象。此外,对群体中农艺性状突出的株系进行了分析,6个株系表现为产量超高亲20%,19个株系的综合性状均较好。  相似文献   
5.
河北省谷田杂草综合防控技术研究   总被引:2,自引:0,他引:2  
春播谷田杂草发生有3个峰期,夏播谷田杂草发生仅1个峰期。综合防控技术方案为:44%单嘧.扑灭WP的最佳剂量为1 800 g/hm2,播后苗前进行土壤处理;整地要平整、紧实;土壤含水量要求达到15%;药后不喷灌,或避开有中到大雨的天气用药。这样药效持续期在45 d以上,能有效控制谷田杂草危害,确保谷子安全生长。  相似文献   
6.
小麦抗叶锈基因Lr44的AFLP分子标记   总被引:1,自引:0,他引:1  
Lr44基因来源于小麦的一个近缘种一斯佩耳特小麦,与Lr33连锁,尚未在生产中广泛使用。该基因在我国小麦资源谱中苗期和成株期抗叶锈良好,具有较大的应用潜力。目前尚未见到关于Lr44基因分子标记的报道。  相似文献   
7.
[目的]在细胞水平上探讨Dehydroheliobuphthalmin (Dehy)与Lapatinib(Lap)联合应用(Dehy+ Lap)的潜在抗肿瘤机制.[方法]利用MTT,Western Blotting等方法以EGFR (wild-type)细胞NCI-H441和EGFR(mutant)细胞NCI-H197...  相似文献   
8.
谷田杂草化学防除面临的问题及发展趋势   总被引:18,自引:0,他引:18  
结合谷田杂草发生状况、化学除草以及谷子生产现状,综合分析了谷田化学除草应注意的事项、存在的主要问题和对策,探讨了谷田化学除草和除草剂的发展趋势。谷田化学除草的发展趋势为以高效除草剂44%谷友(单嘧.扑灭)WP为主导,以44%单嘧.扑灭WP+懒谷3号+间苗剂为主要模式,逐渐过渡到以灭生性除草剂+抗除草剂谷子品种为主要模式。谷田杂草治理向综合防治方向发展。  相似文献   
9.
AIM: To evaluate the relationship between epithelial cell adhesion molecule (EPCAM)/cluster of differentiation 44 (CD44)/cluster of differentiation 24 (CD24) expression and the clinicopathological characteristics/prognosis in 95 gastric cancer patients. METHODS: The expression levels of EPCAM, CD44 and CD24 were detected using the two-step method of immunohistochemistry in 95 gastric cancer patients who underwent surgical excision and were pathologically diagnosed as gastric cancer. RESULTS: There were 56 EPCAM-positive patients (58.95%), 41 CD44-positive patients (43.16%) and 56 CD24-positive patients (58.95%). Thirty patients were both EPCAM and CD44 positive (31.58%), 45 patients were both EPCAM and CD24 positive (47.37%), 32 patients were both CD44 and CD24 positive (33.68%), and 25 patients were EPCAM, CD44 and CD24 positive (26.32%). EPCAM expression was correlated with age, depth of tumor infiltration and WHO histological classification. CD44 expression was correlated with BORRMANN and WHO histological classification as well as CEA value. CD24 expression was correlated with the depth of infiltration, location of the tumor, WHO histological classification and viscera invasion. All positive expression of EPCAM, CD44 and CD24 was correlated with the depth of infiltration, location of the tumor and WHO histological classification (P<0.05). The difference of survival rate between EPCAM positive group and negative group was observed, and the CD44 positive group and negative group had the same result (P<0.05 and P<0.01, respectively). The difference of survival rate between EPCAM+CD44+CD24+ group and EPCAM-CD44-CD24- group was statistically significant (P<0.05). The difference of survival rate between EPCAM-CD44+CD24+ group and EPCAM-CD44-CD24- group was also significant (P<0.05). CONCLUSION: The positive rates of EPCAM, CD44 and CD24 expression are high in gastric cancer tissues and these 3 proteins can be used as primary screening targets.  相似文献   
10.
RSTA14-44 基因是中国协和医科大分子生物学试验室在研究中获得的一个新基因,全长 1124 bp,可读编码框自 100bp~684 bp,编码 194 个氨基酸,预测其编码蛋白质分子量为 21.8 KDa。构建了包含 RSTA14-44 cDNA 全部编码框的 pET30a(+)-14 表达载体质粒,经过聚丙烯酰氨凝胶电泳纯化,免疫家兔制备了抗 RSTA14-44 抗体。Western免疫印迹分析表明,该抗体具有较高的反应性和特异性,适合用作 RSTA14-44 蛋白的进一步研究。  相似文献   
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