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181.
CaMBP-10 is a novel plant endogenous calmodulin-binding protein with important physiological functions. The partial cDNA sequence of this protein was cloned using RT-PCR. The deduced peptide (designated PCBP10) is composed of 74 amino acid residues containing a basic amphiphilic alpha-helix typical for calmodulin-binding proteins. PCBP10 shows very high amino acid sequence homology with plant nonspecific lipid-transfer proteins (nsLTPs). Sequence analysis also reveals that PCBP10 has similar amino acid composition to plant nsLTPs, and seven of the eight conserved cysteine residues are found in PCBP10. Furthermore, the secondary structure features of PCBP10 are very similar to those of plant nsLTPs. In addition, there are striking resemblances between CaMBP-10 and plant nsLTPs in their biochemical and physical properties. Our results suggest that CaMBP-10 is a novel member of the plant and nsLTP gene family, and the Ca(2+)/CaM regulative system may also play roles in lipid metabolism, defense reactions, and the adaptation of plants to natural environment.  相似文献   
182.
Sequence analysis is the basis of bioinformatics, while sequence alignment is a fundamental task for sequence analysis. The widely used alignment algorithm, Dynamic Programming, though generating optimal alignment, takes too much time due to its high computation complexity O(N(2)). In order to reduce computation complexity without sacrificing too much accuracy, we have developed a new approach to align two homologous sequences. The new approach presented here, adopting our novel algorithm which combines the methods of probabilistic and combinatorial analysis, reduces the computation complexity to as low as O(N). The computation speed by our program is at least 15 times faster than traditional pairwise alignment algorithms without a loss of much accuracy. We hence named the algorithm Super Pairwise Alignment (SPA). The pairwise alignment execution program based on SPA and the detailed results of the aligned sequences discussed in this article are available upon request.  相似文献   
183.
《Inorganica chimica acta》2006,359(4):1050-1054
A novel series of inorganic–organic intercalation compounds were prepared by intercalating of alkylviologen dications into the layered vanadium pentoxide in the system of two phases of the liquid and the solid, and characterized by the techniques of X-ray diffraction (XRD), FT infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and UV/vis diffuse reflectance spectroscopy (DRS).  相似文献   
184.
《Developmental cell》2023,58(5):361-375.e5
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185.
He  Ziying  Peng  Yisheng  Guan  Dongsheng  Hu  Zhan  Chen  Yujuan  Lee  Shing Yip 《Plant and Soil》2018,429(1-2):425-436
Plant and Soil - A dominant species of steppe in northern China, Stipa grandis, is gradually being replaced by S. krylovii due to climate change events. The aim of this study was...  相似文献   
186.
Ovoviviparity is reported for the genus Palumbina of Thiotrichinae. The females of eight species were found to retain a hatched first instar larva or a fully developed embryo in the oviduct (vestibulum), which suggests that the females may deposit larvae or mature eggs that are ready to hatch. In the mature embryos, the mandibles and a head capsule were visible and enclosed in chorion. Taking this into consideration, the embryos may contain sufficient nutrition for development within the eggshell, which indicates an ovoviviparous reproduction. The embryos in the oviduct were not dissolved while the early-stage embryos in the anterior portion of the abdomen were destroyed by the treatment of KOH. Therefore, the formation of chorion likely takes place in the oviduct. The female reproductive system of Palumbina displayed typical morphology of ditrysian Lepidoptera although it showed minor variations among the species. The paired reservoirs of the colleterial gland were rather reduced in the species that carried larvae. We assume that this might be related to the ovoviviparous reproductive physiology. The lagena of the spermatheca was present or absent, and if present, the shape and the size were various even in the same species. The species without lagena had a numerous thorn-like structures on the utriculus. The function is possibly related to the maintenance of sperm, but the correlation between the structure and the absence of the lagena remains unclear. Further detailed studies are required to reveal the comprehensive mechanism of the ovoviviparous reproduction in Palumbina.  相似文献   
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Abstract  Five insect growth regulators (IGRs) with juvenile hormone (JH) activity including fenoxy-carb, methoprene, NC-170, NC-184 and NC-196 were selected to study on the relationship between IGRs and feeding behaviour of the fourth instar larvae of Calospilos suspecta (Warren) and the fifth instar larvae of Ostrinia furnacalis Guenee, by topical and dietary applications as well as "diet column" methods. The results indicated that the antifeeding indices of methoprene, fenoxycarb, NC-170, NC-184, NC-196 and toosendanin against the fifth instar larvae of Ostrinia furnacalis in no-choice test were -37. 7, 14. 6, -12. 3, 10. 9, 14. 7 and 62. 2% respectively. Methoprene could stimulate the two species of insects to feed, whereas fenoxycarb had some antifeeding activity, and the effects of all the tested chemicals were different. Therefore, disturbances of IGRs with JH activity on insect feeding behavioural response may be one of the mechanisms of action not to be ignored. Moreover, by comparing "diet column" method with "faeces weight" method, it was suggested that the two methods might be applied in bioassay of antifeeding behaviour.  相似文献   
190.
An improved, forthright, and highly efficient one-pot synthesis of a wide range of pharmaceutically exciting diverse kind of functionalized 2-amino-3-cyano-4H-pyrans and especially bis-pyrans compounds is developed using piperazine as a low-cost and environmentally benign commercially available basic catalyst in aqueous media. The attractive features of this process are simple procedure, short reaction times, high yields, no column chromatographic separation and commercial availability and recyclability of the catalyst. Also, piperazine can catalyze the synthesis of the target compounds on a larger scale. Furthermore, rational mechanism was suggested via GC-Mass analysis of the trapped intermediates.  相似文献   
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