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751.
752.
Plants require substantial resistance against freezing and pathogens for overwintering. These two traits are acquired through
cold acclimation. In contrast to freezing tolerance, molecular basis of disease resistance acquired through cold acclimation
is poorly understood. Recent studies have suggested that pathogenesis-related (PR) proteins that are secreted into the apoplast
during cold acclimation are responsible for the disease resistance. Interestingly, some of the cold-induced PR proteins display
both antifungal and antifreeze activities, suggesting a dual function in protecting plants from overwintering stresses. The
signaling pathway for cold-induced disease resistance is currently unknown but can be independent of pathogen-induced defense
mechanisms. 相似文献
753.
Y Kiso Y Fujiwara T Kimura A Nishitani K Akaji 《International journal of peptide and protein research》1992,40(3-4):308-314
An efficient method for solid phase peptide synthesis was developed, which consists of N alpha-selective deprotection by dilute methanesulfonic acid, in situ neutralization and rapid coupling reaction using benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP) or 2-(benzotriazol-1-yl)oxy-1,3- dimethylimidazolidinium hexafluorophosphate (BOI) reagent. Selective removal of the N alpha-Boc group by dilute methanesulfonic acid was of more advantage than removal by TFA in terms of stability of semipermanent protecting groups and suppression of undesired side reactions. The use of in situ neutralization and rapid coupling method reduced intramolecular aminolytic cyclization by shortening exposure of the deprotected nucleophilic amino group. A successful synthesis of porcine brain natriuretic peptide (pBNP) has been achieved using this efficient solid phase peptide synthesis scheme. 相似文献
754.
Drug susceptibilities of isolates of varicella-zoster virus in a clinical study of oral brovavir 总被引:3,自引:0,他引:3
Susceptibilities to brovavir [1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)-uracil] and acyclovir of clinical isolates of varicella-zoster virus obtained from 58 patients with herpes zoster, included in a clinical trial of oral brovavir, were tested by a plaque reduction method. All 101 isolates were significantly susceptible to brovavir; 50% effective dose of brovavir for these isolates ranged between 0.6-4.0 ng/ml (average: 1.29 ng/ml). Brovavir was about 3,000 times more potent than acyclovir against these isolates. No marked change in the susceptibility of isolates from these patients during treatment with brovavir was observed. 相似文献