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311.
Background
Helical membrane proteins (HMPs) play a crucial role in diverse cellular processes, yet it still remains extremely difficult to determine their structures by experimental techniques. Given this situation, it is highly desirable to develop sequence-based computational methods for predicting structural characteristics of HMPs. 相似文献312.
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Ceratapion basicorne (Coleoptera: Apionidae) is a prospective biological control agent of yellow starthistle (Centaurea solstitialis, Asteraceae: Cardueae), which is an important invasive alien weed in the western United States. Previous studies have shown that it is possible for this insect to oviposit on and complete development on safflower (Carthamus tinctorius) under no-choice laboratory conditions; however, it has never been reported as a pest of safflower. Field experiments were conducted at three sites in eastern Turkey during 3 years to evaluate the risk of attack on safflower by this insect in its native range. At two sites where C. basicorne was the only apionid observed, no safflower plants were attacked despite high attack rates on yellow starthistle test plants (48–98% of plants infested). At a third site, where C. basicorne and three other species in the same genus; C. scalptum, C. orientale, and C. onopordi were present, 8–26% of safflower plants were infested, but none of the insects reared from safflower during 3 years were C. basicorne. Other authors have reported rearing C. basicorne from field-collected plants of only Ce. solstitialis, Ce. cyanus, Ce. depressa, and Cnicus benedictus. Our results indicate that C. basicorne does not attack safflower under field conditions and that its introduction would not pose a risk to this crop. 相似文献
316.
An interactive effect of nitric oxide and 24-epibrassinolide (EBL) or 28-homobrassinolide (HBL) was investigated in Lycopersicon esculentum Mill. cv. K-21. Seeds prior to sowing were exposed to sodium nitroprusside (SNP) (0, 10−5 M or 1 M), a nitric oxide donor, for 8 h, and the resulting seedlings were subsequently sprayed with 10−8 M EBL or HBL at 30-day stage. The analysis of plant samples after 24 h of the EBL or HBL spray showed that the lower SNP
concentration (10−5 M) favored the growth, pigment content, photosynthetic and enzymatic activities, and also improved the antioxidant system.
However, 1 M SNP had inhibitory impact on most of the indices, except the antioxidant system. Brassinosteroids (EBL or HBL),
on the other hand, had a stimulatory impact on the aforementioned indices. The inhibitory effect of SNP (1 M) was neutralized
by the application of BRs, where EBL was more effective than HBL. 相似文献