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1.
自交系9804和9909杂交配制成杂交一代干椒,植株生长旺盛,座果力强,较抗病毒病和疫病,果实指形,纵长17~19cm,横径1.2cm,青熟果绿色,老熟果鲜红色,单果重8.3g,味辣,品质佳,中熟品种,从定植到采收55d(天),一般每667m^2产1500~1900kg。  相似文献   
2.
为了进一步研究前期发现的除草先导化合物2-仲丁氨基-5-(2-氯吡啶-4-基)-1,3,4-噻二唑(BCPT)的结构-活性关系并提高其除草活性,设计并合成了一系列N-(1-甲氧羰基)乙基-N-[5-(2-氯吡啶-4-基)-1,3,4-噻二唑-2-基]酰胺类化合物。其苗后除草活性测定结果表明,所有化合物的活性都远低于BCPT本身。说明BCPT可能具有与传统酰胺类除草剂不同的作用机制。  相似文献   
3.
芝麻是我国重要的特色优质油料作物。提高芝麻单产水平是实现我国粮油安全生产的重要举措。为建立芝麻高产高效栽培模式,本研究以耐密植黑芝麻新品种豫黑芝1号为试验材料,在3个产区(漯河、信阳和三门峡),开展了不同栽培密度(12万株/hm2、15万株/hm2、18万株/hm2、21万株/hm2)下豫黑芝1号产量及产量相关性状变化分析。结果显示,豫黑芝1号在不同产区的生育期差异明显;种植密度对豫黑芝1号的株高、有效果节数、主茎果轴长、单株蒴果数、千粒重和单株产量等性状变化程度不同;对小区产量及单株产量影响显著。在21万株/hm2密度下,豫黑芝1号单产水平最高达到1463.33 kg/hm2(三门峡)。研究为芝麻高产高效生产提供了技术支持。  相似文献   
4.
观察补中益气丸对糖尿病大鼠胃组织MuC1、COX-1、COX-2、cNOS、iNOS不同病程表达变化及其相互作用的影响、大鼠随机分为正常组。模型组和中药组,采用STZ腹腔注射结合乙醇灌胃的方法建立糖尿病大鼠胃黏膜损伤模型.检测胃组织NO、PGE2、6-ketoPC-F1d、MuCl、COX-1、cOX2、cNOS和iNOs随病程的表达变化及其相互作用。结果显示,糖尿病大鼠出现胃黏膜损伤和胃肠功能紊乱,胃组织MUC1、COX2、iNOS发生显著变化.MUC1随病程进展逐渐降低,iNOs和COX-2表现为早期活性降低,晚期活性升高,PGE2、6-keto—PGF1d和NO随病程显著升高,相关分析发现.COX1与cNOS呈显著正相关,与iNOS呈著负相关。补中益气丸能调节MUC1、COX-2、iNOS的表达及其相互作用,阻止胃黏膜损伤。结果表明,STZ腹腔注射结合乙醇灌胃的方法可成功诱导糖尿病大鼠胃黏膜损伤模型,iNOS与COX2可能为相互协作和相互介导的关系,在糖尿病胃黏膜损伤方面起重要作用,补中益气丸通过升高MUC1、降低iNOS和COX-2的表达及其相互作用,阻止胃黏膜损伤和糖尿病的发展。  相似文献   
5.
Anatid herpesvirus 1 (AHV-1) CH virulent strain was first isolated from an infected duck and it was found that this virus strain could induce cytopathic effect (CPE) in duck embryo fibroblast (DEF). Following AHV-1 infection, DEF showed morphological changes such as cell rounding, improved refractivity and detachment from the culture surface. However, its pathological characteristics were not adequately known. Related studies were performed and the results showed that syncytium formation could be observed as the other type of CPE in AHV-1 infection. Hematoxylin-eosin staining and 4’, 6-diamidino-2-phenylindole (DAPI) staining of infected DEF were each used to visualize the shape and distribution of chromatin within nuclei and nuclear fragmentation was observed. Chromatin condensation and margination, as well as formation of apoptotic bodies were observed by transmission electron microscopy (TEM). DNA ladder formation was detected in AHV-1 infected cells and apoptosis of the infected DEF was also detected by flow cytometry analysis of Annexin V-FITC/PI staining method. Therefore, it was suggested that AHV-1 virulent strain can induce syncytium and apoptosis in DEF. Syncytium formation and apoptosis observed in this study may contribute to the elucidation of AHV-1 pathogenesis.  相似文献   
6.
J.J. Hu  Y.C. Tian  Y.F. Han  L. Li  B.E. Zhang 《Euphytica》2001,121(2):123-127
The performance of insect-resistant transgenic poplar trees (Populusnigra) expressing a Cry1Ac gene from Bacillus thuringiensis subsp. Kurstaki HD-1 against poplar defoliators was evaluated in the field at the Manas Forest Station in Xinjiang Uygur Autonomous Region during1994–1997. The results showed that the average percentage of highly damaged leaves on the transgenic trees was 10% while that on the control trees in nearby plantations reached 80–90%. The average number of pupae per m2 of soil at 20cm depth in transgenic poplar plantation was 18 which was only 20% of that found in the non-transgenic control field. The number of pupae and the leaf-damage on transgenic trees described above are all far below the threshold set for chemical protection measures. The non-transformed poplar trees grown in the same plantation with the transgenic trees were also protected indicating that cross protection occurred between these two kinds of trees. Insect-resistant transgenic poplar trees have a potential application value in afforestation. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
7.
Progress made in the in situ gynogenesis technique since 1990 now allows production of a high number of maize (Zea mays L.) doubled-haploid (DH) lines. The aim of the study was to compare DH lines versus selfing lines for testcross performance. DH and single-seed descent (SSD) lines were produced from random S1 progenies of a broad-base population. For grain yield, kernel moisture, plant height, ear height and leaf length, the three population means were similar. Except for kernel moisture, the genetic variance of DH lines was nearly twice as high as the genetic variance of S1 families, as expected. On the other hand, genetic variance among SSD lines was only 1.5 times higher than the genetic variance of S1 families. This lower variance could be due to a selection bias in the method of production of SSD lines. However, for all traits, heritability of SSD or DH lines was higher than heritability of S1 families. Epistasis effects in DH progenies were not significant. The consequence was a high correlation between S1 testcross progenies and DH or SSD testcross progenies, meaning that the S1 testcross value can be used to select the best families from which DH lines will be extracted. As a whole, the observed variation in DH lines appeared to be more in accordance with the observed variation among S1 families than with the observed variation among SSD lines.  相似文献   
8.
FANG Yong  HOU Qi  LU Yu 《园艺学报》2013,29(3):442-448
AIM:To explore the inhibitory mechanism of isorhapontigenin (ISO) on the proliferation, migration and invasion of UMUC3 bladder cancer cells. METHODS:Human UMUC3 bladder cancer cells were pretreated with ISO, and the proliferation of the cells was observed under phase-contrast microscope and by ATPase assay. The expression of cyclin D1 was determined by RT-PCR and Western blotting. The cell cycle alteration was detected by flow cytometry, and the cell migration was examined by wound-healing assay. RESULTS:Over 20 μmol/L of ISO significantly inhibited the proliferation of UMUC3 cells with the IC50 of (22.5±2.8) μmol/L. The mRNA and protein levels of cyclin D1 in UMUC3 cells were markedly decreased after treatment with ISO. Exposure of UMUC3 cells to low dose (5 μmol/L) of ISO led to significant induction of G0/G1 growth arrest at both 12 h (58.82%) and 24 h (63.94%), compared with the negative control cells (47.33%) without inducing obvious apoptosis. ISO at dose of 5 μmol/L also markedly inhibited the cell migration. CONCLUSION:ISO significantly exhibits inhibitory effects on the proliferation and migration of human bladder cancer cells by down-regulation of cyclin D1 expression accompanying with G0/G1 cell cycle arrest.  相似文献   
9.
"头顶云雾脚踩霜,荞麦粑粑萝卜汤"这曾是旧光明村人生活的真实写照。光明村位于漾濞彝族自治县东部,苍山西坡腹地,居住着彝、汉、白、傣、傈僳5个民族,少数民族人口占总人口的65.04%。    相似文献   
10.
Since cattle are widely infected by bovine viral diarrhea virus (BVDV) in India, we searched for pestivirus infection in yaks. Of 71 pure and crossbred yaks from Himalayan region, pestivirus antigen was detected by Ag-ELISA in three animals. Pestivirus in leukocyte and cell culture isolated virus samples originating from positive yaks was also confirmed by RT-PCR using panpestivirus specific primers selected from 5'-untranslated region (5' UTR). The 5' UTR, N(pro) and E2 regions were sequenced and used for genetic typing. Phylogenetic analysis revealed that pestiviruses detected in three Himalayan yaks were similar genetically, belonging to BVDV-1. Antigenic characterisation of yak pestivirus also confirmed the typing as BVDV-1. This is the first report on the identification of BVDV type 1 in yaks.  相似文献   
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