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Fusarium wilt and root-knot are important diseases of tomato. The use of chemical is becoming less appealing because of the health implications. Also, the chemicals required are often not within the reach of farmers in most of the developing part of the world. This research is aimed at finding an alternative mode of control. Tomato variety Roma VF inoculated with Meloidogyne and Fusarium were treated with 2 g/kg soil neem seed powder in the screenhouse and 2 Mg ha ? 1 in the field. An untreated and Furadan treated plot in the field served as control. Neem seed powder significantly reduced the disease severity of Fusarium and root-knot in both screenhouse and field. Results suggest the possible use of neem seed powder for control of the root-knot nematodes - Fusarium wilt disease complex.  相似文献   
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In an attempt to understand ribosome-induced GTP hydrolysis on eEF2, we determined a 12.6-Å cryo-electron microscopy reconstruction of the eEF2-bound 80S ribosome in the presence of aluminum tetrafluoride and GDP, with aluminum tetrafluoride mimicking the γ-phosphate during hydrolysis. This is the first visualization of a structure representing a transition-state complex on the ribosome. Tight interactions are observed between the factor's G domain and the large ribosomal subunit, as well as between domain IV and an intersubunit bridge. In contrast, some of the domains of eEF2 implicated in small subunit binding display a large degree of flexibility. Furthermore, we find support for a transition-state model conformation of the switch I region in this complex where the reoriented switch I region interacts with a conserved rRNA region of the 40S subunit formed by loops of the 18S RNA helices 8 and 14. This complex is structurally distinct from the eEF2-bound 80S ribosome complexes previously reported, and analysis of this map sheds light on the GTPase-coupled translocation mechanism.  相似文献   
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Argentavis magnificens , the largest known flying bird, had a wingspan of over 6 m with a mass of 80 kg. Its enormous size suggests that it was not a powerful flapper. The wing shape is inferred as more like that of large extant birds that soar relatively slowly on thermals over land than of large pelagic birds that soar over water. Its high wing loading would have allowed it to fly in moderate to strong winds that must have been prohibitive for the largest known contemporary thermal soarers. The high wing loading would have been ill-suited to flight under poor thermal conditions, but it would have been useful in slope-soaring on uprising air current against hillsides. We propose that Argentavis had a large home range that included a nesting area in the mountains of western and northwestern Argentina, and a feeding area in the Pampas.  相似文献   
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Emphysema and liver cirrhosis can be caused by the Z mutation (Glu342Lys) in the serine protease inhibitor α1-antitrypsin (α1AT), which is found in more than 4% of the Northern European population. Homozygotes experience deficiency in the lung concomitantly with a massive accumulation of polymers within hepatocytes, causing their destruction. Recently, it was proposed that Z-α1AT polymerizes by a C-terminal domain swap. In this study, small-angle x-ray scattering (SAXS) was used to characterize Z-α1AT polymers in solution. The data show that the Z-α1AT trimer, tetramer, and pentamer all form ring-like structures in strong support of a common domain-swap polymerization mechanism that can lead to self-terminating polymers.  相似文献   
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目的:研究慢性肾病(CKD)患者血清可溶性细胞粘附分子-1(soluble intercellular adhesionmolecule-1,sICAM)的变化与临床意义。方法:用双抗体夹心ELISA方法,对52例CKD患者及20例健康对照人群的sICAM-1水平进行检测分析。52例CKD患者中,其中27例为CRF血液透析患者;25例肾功能正常CKD患者。结果:CKD组患者sICAM-1水平明显高于对照组(105.42±61.95)(P<0.01);肾功能正常CKD组和CKD-CRF组sICAM-1水平均显著高于对照组(P<0.01);CRF组sICAM-1水平明显低于肾功能正常CKD组(P<0.01);但高于对照组(84.80±19.61/164.08±70.66/54.61±5.48)(P<0.01)。结论:sICAM-1水平在慢性肾脏病中明显升高,CRF组病人sICAM-1水平低于CKD肾功能正常患者,提示透析过程中可能有sICAM溢出,吸附并丢失入透析液中(1),或可能是肾纤维化为主的病变使sICAM-1表达下降。  相似文献   
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