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排序方式: 共有140条查询结果,搜索用时 15 毫秒
1.
研究了国产替米考星注射用药对人工感染多杀性巴氏杆菌病猪的治疗效果,用断奶仔猪进行试验,为临床使用提供了依据.结果表明,替米考星治疗急性猪肺疫效果确实, 推荐剂量为10 mg/kg体重.  相似文献   
2.
AIM: To investigate expression of CD44s in lung cancer and it's clinical significance. METHODS: A total of 117 primary lung cancer from patients were examined for CD44s expression by immunohistochemical staining. RESULTS: CD44s mostly expressed in non-small cell lung cancer (NSCLC) but not in small ecll lung cancer (SCLC), and squamous cell carcinoma(SCC) showed much stronger expression of CD44s than adenocarcinoma(ADC)(P<0.05). In comparison of the lung cancer with/ without lymph node metastasis, the latter showed stronger expression of CD44s(P<0.01). According to TNM, there was a distinct statistic difference between early stage and advanced stage(P<0.05). CONCLUSION: CD44s might be a better indicant in histological classification of lung cancer, lymph node metastasis, clinical stage and prognosis.  相似文献   
3.
Leaf rust, caused by the fungus Puccinia triticina, is one of the most damaging rust diseases of wheat in Russia. Populations of Ptriticina were monitored in seven regions of Russia from 2001 to 2018, with a total of 5,191 single urediniospore isolates from bread wheat (Triticum aestivum) being analysed. Populations have changed significantly in all regions since 2012, after 2 years of drought (2010–2011). Regional collections of Ptriticina were also significantly different between the two periods 2001–2009 and 2012–2018, with changes along two geographic gradients from West Siberia to the north-west and south-west (North Caucasia) of the European part of Russia. All tested isolates were avirulent to resistance gene Lr9 in 2001–2009 but, since 2010, virulence to Lr9 has occurred and annually increased in the Asian part of Russia (Ural and West Siberia) due to deployment of cultivars with the Lr9 gene. Virulence to Lr2a and Lr15 was considerably lower in Dagestan (6%–33%) and all European regions (35%–67%) than in Asian regions (84%–96%). During 2001–2009, virulence on Lr1 was also lower in Dagestan (33%) and the European regions (50%–77%) than in Asia (91%–96%); however, by 2012–2018, nearly all isolates were virulent on Lr1. Remarkable changes were observed in frequencies of Ptriticina races defined by their virulence/avirulence to Lr1 and Lr2a genes. We postulate the Ptriticina population in Dagestan is specific to that area and pathogen populations in European and Asian parts of Russia are distinct.  相似文献   
4.
小麦抗叶锈病Lr35基因同源序列RGA1侧翼序列的扩增与分析   总被引:1,自引:0,他引:1  
利用小麦抗叶锈病近等基因系材料TcLr35,根据已扩增出的Lr35相关基因组DNA片段RGA1设计3对特异性引物,通过热不对称交错PCR技术获得2个有效扩增片段,将目的片段回收纯化,连接到pGEM-TEasy载体,转化EcoliDH5α感受态细胞中,经EcoRⅠ酶切,验证插入片段,选择合适菌液测序。获得了2条侧翼序列,长度分别为511bp和614bp,与RGA1重叠区分别为293bp和509bp,分别向3'端和5'端延长了208bp和100bp,拼接后序列为915bp。经BLASTn同源性比较与小麦抗叶锈病基因Lr21同源性为93%(score值为674,E值为0.0),与含有Lr10基因的450Kb大片段重叠群同源性为90%(score值为260,E值为7e-66),该研究为克隆Lr35目的基因奠定了基础。  相似文献   
5.
Amplified fragment length polymorphism (AFLP) analysis was carried out in Thatcher, near isogenic lines (NILs) carrying different genes conferring resistance against wheat leaf rust, and TcLr45 x Thatcher F2 progenies were used to develop markers for Lr45 gene. Sixty AFLP primer combinations were screened and most of them provided clear amplification products, 31 primer combinations displayed polymorphism of TcLr45 in 23 NILs. Two AFLP markers closely linked to the gene Lr45 were acquired: P-AGG/M-GAG261 bp, which was found closely linked to the Lr45 locus at a distance of 0.6 cM on one side, and P-ACA/M-GGT105 bp, which was found at a distance of 1.3 cM on the other side. The specific bands were cloned and subsequently sequenced. The 261-bp fragment produced by P-AGG/M-GAG showed 86% similarity with the sequence of Vulgare Hart I gene; the 105-bp fragment produced by P-ACA/M-GGT showed 96% similarity with the phosphatidylserine decarboxylase gene of the Triticum monococcum. Both included an open reading frame (ORF).  相似文献   
6.
黑农 4 4属于高脂肪、高产品种 ,其基础与亲本的遗传有关 ,在后代选择上主要是按着母本哈85 - 6 437(黑农 37)生态类型选择。不同密度穴播比条播增产 ,在 15~ 2 5万株 /hm2 时穴播较条播增产 0 .9%~ 13.1% ,同时脂肪含量提高 ;黑农 4 4主要栽培要点是 :密度 2 0~ 2 5万株 /hm2 ,采用穴播 ,种肥施磷酸二铵 15 0~ 187.5kg/hm2 ,实行通透管理 ,防治病虫草害。  相似文献   
7.
150个小麦品种(系)抗叶锈基因Lr35分子鉴定   总被引:11,自引:1,他引:11  
小麦抗叶锈基因Lr35是成株抗性基因,在二叶期即表现连续抗性,被认为是有用的抗病资源。本研究利用以PCR为基础的STS、SCAR分子标记技术,对150个小麦品种(系)进行了分析,检测出8个小麦品种(6068,白蚰包,中麦9,早洋,碧玛1号,小偃7631,东方红3号和Madsen)含有Lr35基因。结合室内接种鉴定技术 (叶锈菌株为对Lr35无毒力的99-8-11-5),结果表明,这8个小麦品种虽在分子水平上含有Lr35基因,但在侵染类型上具有一定差异,其中东方红3号表现对菌株的亲和性。  相似文献   
8.
宁夏小麦品种慢锈基因Lr34/Yr18的分子检测   总被引:1,自引:0,他引:1  
Lr34/Yr18是重要的小麦慢叶锈/慢条锈基因,可用于小麦锈病抗性改良。为了明确Lr34/Yr18基因在宁夏小麦中的分布特点,利用STS标记csLV34对111份宁夏小麦品种中慢锈基因Lr34/Yr18的等位变异进行了分子检测,并且进行了成株期条锈病抗性鉴定。结果表明,20份材料携带Lr34/Yr18基因,占18.0%。不同来源的小麦品种中Lr34/Yr18基因分布频率不同,农家品种中分布频率最高,占90.9%;引进品种中所占比例为14.3%;育成品种中所占比例最低,仅占7.7%。含有Lr34/Yr18基因的品种对条锈病具有较好的抗性,可作为今后宁夏小麦抗锈病育种的重要抗源。  相似文献   
9.
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   
10.
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   
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