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排序方式: 共有365条查询结果,搜索用时 15 毫秒
351.
352.
M K Biswas M Hossain R Islam 《中国马铃薯》2005,19(6):321-325
In vegetatively propagated crops,once system ati-cally infected w ith a viral disease,the pathogen canpassed from one generation to the next[1].Especially inpotato,contam ination by a pathogen can severely re-duce the total yield of the crop[2].Traditionally,potatovarieties have been and still m aintained in a fieldgene bank.M aintenance of potato germ plasm in thefield is a m ajor consum er of tim e,m anpower andspace aside from diseases and environm ental stresses.The m ajor disadvantage of … 相似文献
353.
小麦叶片的衰老会导致产量的损失,而叶绿素降解是小麦叶片衰老的明显特征,分析小麦叶绿素降解过程中脱植基反应的相关基因叶绿素酶(TaCLH)和脱镁叶绿素水解酶(TaPPH)在春性小麦叶片衰老过程中的作用,为解析小麦叶绿素降解的分子机制提供参考。以10个春性小麦品种为参试材料,对衰老过程中TaCLH和TaPPH的相对表达量进行测定,结合不同品种在开花后不同时期的相对叶绿素含量(SPAD)、功能绿叶面积(GLAD)和叶绿素荧光参数的变化规律,研究叶片衰老过程中TaCLH和TaPPH与SPAD、GLAD和叶绿素荧光参数的相关关系。结果表明,TaPPH的相对表达量与GLAD、SPAD及叶绿素荧光参数[ETR、Fv/Fm、Y(Ⅱ)]等生理指标之间存在极显著负相关关系,与TaCLH相对表达量存在极显著正相关关系,表明TaPPH在春小麦叶绿素降解过程的脱植基反应中起主要作用。 相似文献
354.
Miyoshi T Tsuji N Islam MK Kamio T Fujisaki K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1471-1473
RNA interference (RNAi) has been recently exploited to determine gene function by degrading specific mRNAs in several eukaryotic organisms. We constructed a double stranded RNA (dsRNA) from a previously cloned Haemaphysalis longicornis serine proteinase (HlSP) gene to test the importance of the function of the HlSP gene product during blood-feeding. Growth of unfed ticks treated with HlSP dsRNA was significantly inhibited compared to that of PBS-treated ticks. This inhibition was supported by the level of HlSP mRNA. HlSP may play a crucial role for blood-feeding in these ticks. This is the first report on gene silencing of a functional serine proteinase in hard ticks. 相似文献
355.
Uddin MJ Nuro-Gyina PK Islam MA Tesfaye D Tholen E Looft C Schellander K Cinar MU 《Veterinary immunology and immunopathology》2012,147(3-4):211-222
The Toll-like receptor (TLR)4 is critical for the recognition of Gram-negative bacterial lipopolysaccharide (LPS) but in porcine peripheral blood mononuclear cells (PBMCs) it may cooperate with other TLRs and lead to the production of inflammatory cytokines. Therefore, we analyzed TLR1-10 mRNA expression in porcine PBMCs stimulated with LPS over time (1-48 h) by using quantitative real-time PCR and cytokine proteins level by ELISA in culture supernatant. TLR1-10 mRNA was detectable in porcine PBMCs. When compared with the control (non-stimulated), TLR1 mRNA were increased (p<0.05) at 3 h after challenge with 1 μg/ml LPS, whereas TLR1 and TLR2 mRNA were increased (p<0.01) at 6 h after challenge with 10 μg/ml LPS. TLR4 increased (p<0.001) at 3h after challenge with LPS and remained constant. TLR5 and TLR6 mRNA increased (p<0.05) at 9 h and 1 h after of LPS stimulation, respectively. The mRNA of CD14 and MD2 were increased (p<0.001) at 1h after LPS stimulation. Additionally, at most of the time analyzed, the mRNA expression increased with the dose of LPS. The LPS concentration had influence (p<0.05) on all the TLRs expression except TLR10; whereas time had effect (p<0.05) on all TLRs expression except TLR2, 3, 6 and 10. When compared to the control, the cytokines IL1b, IL8 and TNFα proteins were increased (p<0.001) immediately at 1 h after LPS stimulation and remained constant till 48 h. IL12b was increased (p<0.001) 12 h after challenge with 10 μg/ml of LPS. Although IL8 level was the highest, the higher (p<0.05) expression of all these inflammatory cytokines indicate that upon interacting with TLRs, LPS exerted inflammatory response in PBMCs through the production of Th1 type cytokines. The production of cytokines was influenced (p<0.001) by both the dose of LPS and the stimulation time. Hence, the porcine PBMCs are likely able to express all members of TLRs. 相似文献
356.
Efrem Bechere David D. Fang Hirut Kebede Robert G. HardinIV Md. S. Islam Ping Li Jodi Scheffler 《Euphytica》2017,213(7):160
Cotton cultivars with reduced fiber-seed attachment force have the potential to be ginned faster with less energy. The objective of this study was to identify quantitative trait loci (QTL) for net ginning energy requirement (NGE), and its relationship with other fiber quality traits in upland cotton. Two cotton lines, TAM 182-34 ELS and AR 9317-26, with significant differences in NGE and fiber-seed attachment force, were crossed and 285 F2 plants derived from a single F1 plant were planted in the field and leaf samples collected for DNA marker analysis (Population A). Individual F3 plants and the two parents were planted in replicated progeny rows. The cotton was ginned on a 10-saw laboratory gin stand. Electrical power used by the gin was measured and recorded with a Yokogawa CW121 power meter. Fiber quality attributes were measured using a high volume instrument. A total of 455 SSR marker loci were used to construct a linkage map. Two QTLs were identified for NGE on chromosomes 12 and 20, associated with markers CIR148 and DPL0600, explaining 14 and 8.8% of the phenotypic variation, respectively. NGE shared the same genomic region with fuzz percent on chromosome 12. Population B, consisting of 260 F2 progeny from the reciprocal cross AR 9317-26 X TAM 182-34 ELS, was used to confirm these QTLs by analyzing SSR markers mapped on Chrs 12 and 20. These QTLs (qNGE-c12 and qNGE-c20) were confirmed and appeared stable. Further validation of significantly associated markers on different populations is necessary prior to implementation in marker-assisted selection. 相似文献
357.
在孟加拉锡尔赫特地区Khasia部落家庭园地或其周围,对基于槟榔叶农林复合系统的文化产业与经济管理技术进行了调查研究。Khasia是一个受教育较普及的社区;该区家庭平均大小为7.68人,男女比率为141:100;家庭园地里物种丰富。在槟榔农林复合系统中共有15个木材品种,22个园艺种,6个药用植物种,以及13个一年生作物种(包括一些叶用蔬菜),7个香味料植物种和5个竹类种。Khasia也是一个经济繁荣区,最小家庭月收入57美元。槟榔收益是当地居民收入的重要来源。该区95.45%的家庭涉及槟榔农事。槟榔人工林年平均收入约为1157美元/公顷,此农林复合生产项目的收益.投入比率为4.47。槟榔人工林区内物种丰富度较高,对维持农林复合系统可持续性以及系统内生物多样性保护具有重要意义。图2表3参19。 相似文献
358.
Nahar Sharmin Hasan Md. Faruk Sikdar Biswanath Islam Md. Asadul 《Journal of Crop Science and Biotechnology》2021,24(5):521-531
Journal of Crop Science and Biotechnology - The present investigation was carried out to investigate the effects of rhizosphere bacteria on growth and rice yields. Also, isolation and... 相似文献
359.
The mildew reactions of the second generation of doubled haploid (DH) plants, derived from anther culture of crosses among three spring barley lines carrying different Mla mildew resistance alleles and the cv. ‘Pallas’, were analyzed by using a set of three European and one Israeli mildew isolate. The results indicated, (1) a significant level of distortion segregation in favour of resistant DH genotypes, which was possibly due to linkage of mildew resistance genes on chromosome 5 with genes for plant regeneration and (2) various degrees of dominance for the different resistance genes studied as well as the possible action of modifier genes. 相似文献
360.
Hyun Ah Jung Md. Nurul Islam Chan Mee Lee Hyong Oh Jeong Hae Young Chung Hee Chul Woo Jae Sue Choi 《Fisheries Science》2012,78(6):1321-1329
In the present study, we investigated the antidiabetic potential of fucoxanthin via the inhibition of rat lens aldose reductase (RLAR), human recombinant aldose reductase (HRAR), advanced glycation end-product (AGE) formation, protein tyrosine phosphatase 1B (PTP1B), and α-glucosidase. Fucoxanthin displayed potent inhibitory activity against AGE formation and HRAR and RLAR activity. In addition, fucoxanthin showed potent inhibitory activity against PTP1B. However, it did not show α-glucosidase inhibitory activity below 200 μM. In addition, our kinetic study revealed that fucoxanthin competitively inhibited RLAR, while it showed mixed-type inhibition against PTP1B. In order to confirm enzyme inhibition, we predicted the 3D structure of PTP1B using Autodock 4.0 to simulate the binding of fucoxanthin. Docking simulation results demonstrated that three residues of PTP1B (Phe30, Phe52, and Gly183) interact with the two hydroxyl groups of fucoxanthin. In addition, the binding energy was negative (?7.66 kcal/mol), indicating that the three hydrogen bonds may stabilize the open form of the enzyme and potentiate tighter binding to the active site of PTP1B, resulting in more effective PTP1B inhibition. The results of the present study therefore clearly demonstrate the promising potential of fucoxanthin as a therapeutic intervention for the management of diabetes as well as diabetes-associated complications, which could be explored further. 相似文献