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排序方式: 共有138条查询结果,搜索用时 15 毫秒
41.
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寄生原虫是一类单细胞真核生物,是人和动物疾病的重要病原之一,给人类健康和畜牧业发展造成了严重的危害。DNA解旋酶是一类参与几乎所有生物DNA代谢的重要解旋酶,目前原虫DNA解旋酶的研究主要集中在恶性疟原虫,且被报道的DNA解旋酶多为人类或酵母的同源物,其保守基序与人类、酵母等都存在差异,是研究抗原虫药物的重要潜在靶标。笔者主要综述了经典解旋酶的保守结构域及其功能特点,介绍了各个解旋酶的极性与偏好底物等生化特性,汇总了已报道原虫DNA解旋酶的种类。目前报道的DNA解旋酶大多集中在恶性疟原虫,其中疟原虫含18种,利士曼原虫含3种,布氏锥虫和兔脑原虫均含2种,弓形虫含1种。同时介绍了目前原虫中较为引人关注DNA解旋酶:RecQ家族、DEAD-box家族、UvrD解旋酶家族和RuvB家族的功能研究进展,其中DEAD-box家族中有3种疟原虫特异性解旋酶PfPSH1/H2/H3并未在宿主人类中发现相似物,另一种解旋酶UvrD则与人类、小鼠、秀丽隐杆线虫等无同源性,而与细菌、真菌等同源性较高。笔者对原虫DNA解旋酶的基本特性和功能进行综述,阐述了目前原虫DNA解旋酶的研究进展及其作为药物靶标的可能... 相似文献
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用自选及从省内外引进的13个自交系(其中有5个自交系具有贵州地方血缘),按Griffing完全双列杂交方法四组配78个杂交组合,进行了田间试验。估算了这些自交系产量性状的一般配合力效应。结果表明,自交系大013﹑交51、5003的一般配合力较高。 相似文献
45.
Specific chromosome defect associated with human small-cell lung cancer; deletion 3p(14-23) 总被引:25,自引:0,他引:25
J Whang-Peng C S Kao-Shan E C Lee P A Bunn D N Carney A F Gazdar J D Minna 《Science (New York, N.Y.)》1982,215(4529):181-182
A specific, acquired chromosomal abnormality (deletion 3p) has been found in at least one chromosome 3 in 100 percent of the metaphases in 12 of 12 cell lines cultured from human small-cell lung cancer tissue and in 2-day tumor culture specimens from three patients. Analysis of the shortest region of overlap shows the deletion to be 3p(14-23). This specific change was not seen in five of five lung cancer cell lines other than small-cell lung cancer or in two lymphoblastoid lines cultured from cells of small-cell lung cancer patients whose tumors had the 3p deletion. 相似文献
46.
High levels of intracellular bombesin characterize human small-cell lung carcinoma 总被引:25,自引:0,他引:25
T W Moody C B Pert A F Gazdar D N Carney J D Minna 《Science (New York, N.Y.)》1981,214(4526):1246-1248
"Small cells" or "oat cells" characterize a virulent form of lung cancer and share many biochemical properties with peptide-secreting neurones. The neuropeptide bombesin is present in all small-cell lines examined, but not in other lung cancer cell lines, suggesting that bombesinergic precursor cells in lung may give rise to this disease. 相似文献
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Minna Nurminiemi Sten Madsen Odd Arne Rognli Âsmund Bjørnstad Rodomiro Ortiz 《Euphytica》2002,127(1):123-132
Variation in agronomic and quality characteristics was investigated in 220 Nordic spring barley cultivars across distinct
environments (6 locations during 3 years) in the Nordic Region of Europe. The objectives of this research were to determine
the importance of the genotype by environment interaction in all characteristics evaluated and to establish the relationship
among different stability statistics for grain yield. Combined analysis of variance across locations indicated that both environments
and genotype by environment interactions influenced significantly the cultivar phenotypes for all characteristics, irrespective
of their type (row number) or earliness. The first two interaction principal component axes of the additive-main-effects-and-multiplicative-interaction
(AMMI) model accounted together between 35% and 75% of the total genotype-by-environment interaction for all characteristics.
Grain yield was, on average, higher in 2-row than in 6-row cultivars, which were significantly earlier in heading and grain
maturity than the former. However, in some of the most northern locations, 6-row barley cultivars significantly outyielded
on average 2-row barley lines. The genotype by location interaction variance (σ2
GL) accounted by each genotype was significantly associated to the deviation from regression (Tai's λ) while the coefficient
of regression (β) was significantly correlated to the IPCA1 and IPCA2 of the AMMI model in 2-row, 6-row and early barley cultivars.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
49.
Rodomiro Ortiz Minna Nurminiemi Sten Madsen Odd Arne Rognli Åsmund Bjørnstad 《Euphytica》2002,126(2):283-289
Accurate assessments of genetic gains ensuing from plant breeding for the most important agronomic characteristics in Nordic
spring barley (Hordeum vulgareL.) are not available. Hence this research was aimed to determine the rate of genetic improvement in the Nordic barley breeding
pool. This study included 90, 2-row spring barley cultivars released (1942–1988) and29, 6-row spring barley cultivars released(1930–1991)
adopted by Nordic farmers that were tested in four Nordic locations for three consecutive years. Relative genetic gain owing
to plant breeding was 13% in2-row barley and 34% in 6-row barley for grain yield. The absolute gain for this characteristic
was 13 ± 3 kg ha-1 year -1 in 2-row barley, and22 ± 3 kg ha-1 year-1 in6-row barley. Improved yield was achieved in Nordic barley by reducing plant height(0.20 ± 0.04 cm year-1 for 2-rowbarley and 0.16 ± 0.06 cm year-1for 6-row cultivars), thereby reducing significantly lodging (0.5 ± 0.1%year-1 and 0.4 ± 0.1year-1), and increasing significantly the harvest index (0.0008 ± 0.0002year-1 and 0.0018 ± 0.0002year-1). Additionally, in 2-row spring barley cultivars resistance to powdery mildew (0.19 ± 0.08% year-1)and thousand-kernel weight (0.07 ±0.03 g year-1) were also significantly enhanced, whereas hectoliter weight was improved (0.06 ± 0.02 kg year-1)in 6-row barley cultivars in the period investigated.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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