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421.
Male large odorous frogs(Odorrana graminea)have been shown to have a rich vocal repertoire and their calls contain harmonics that extend into the ultrasonic range,much like calls of male O.tormota,a sympatric species.Whereas vocalizations of male O.tormota exhibit nonlinear characteristics and contain individual signatures,it is unclear whether or not those of O.graminea do.We carried out an extensive study of the vocalizations of male O.graminea with the goal of investigating whether they:(1)contained nonlinear phenomena(NLP),(2)carried individual signatures.We recorded and analyzed 1770 vocal calls from nine males.Their calls were classifiable into two distinct categories(one-note calls and multi-note calls).Of these,one-note complex/steep-frequency modulation call was the most abundant call-type.These calls showed diverse frequency modulation patterns,and abundant presence of NLP.Various basic spectral and temporal pa ra meters of such calls were individually distinct.Kruskal-Wallis Analysis of Rank test showed that the calls from individual males differed significantly.Subsequent discriminant function analysis(DFA)showed that 54.7%of the calls could be correctly assigned to individual.These results suggested that male O.graminea might be able to discriminate neighboring frogs from strangers acoustically.However,further research is necessary to demonstrate this capacity behaviorally. 相似文献
422.
Jiang-Li DONG Bo ZHOU Gang SHENG Tao WANG 《植物学报(英文版)》2005,47(8):978-987
Elevated expression of the rotavirus VP6 antigen in transgenic plants is a critical factor in the development of a safe and effective rotavirus vaccine. Using codon optimization, a gene that encodes the inner capsid protein VP6 of the human group A rotavirus was synthesized (sVP6). The VP6 and sVp6 genes were transformed into tobacco (Nicotiana tabacum L.) plants using Agrobacterium tumefaciens. The expression level of the sVP6 gene in transgenic plants was 3.8-34-fold higher than that of controls containing the non-modified VP6 gene, accounting for up to 0.34% of the total soluble protein (TSP). Then, BALB/ c female mice that had been gavaged weekly with 10 mg TSP containing 34 p.g VP6 protein, in which VP6-specific serum IgG and mucosal IgA antibodies were investigated. The severity and duration of diarrhea caused by simian rotavirus SA-11 challenge were reduced significantly in passively immunized pups, which indicates that anti-VP6 antibodies generated in orally immunized female mice can be passed onto pups and provide heterotypic protection. An edible vaccine based on the VP6 of human rotavirus group A could provide a means to protect children and young animals from severe acute diarrhea. 相似文献
423.
Hui ZHU ZuoMin ZHOU Ran HUO XiaoYan HUANG Li LU Min LIN LiRong WANG YaDong ZHOU JianMin Ll and JiaHao SHA*LaboratoeProductivedicine Naliingdical Universl NaangsuChina 《Acta biochimica et biophysica Sinica》2004,(3)
The selective degradation of many short一lived or
abnormal Proteins in eukaryotic cells 15 carried out by the
ubiquitin system.In this Pathway,Proteins are targeted
for degradation by covalent ligation to ubiquitin,a highly
conserved 76一resid… 相似文献
424.
Suppression of angiotensin Ⅱ stimulated responses in aortic vascular smooth muscle cells of experimental cirrhotic rats 总被引:1,自引:0,他引:1
ZHANG RU GUO LIANG WANG PI LI ZHANG YING XIONG WEN BO ZHANG XING PENG WANG DE LING YIN QING JING 《Cell research》1999,(2)
INTRODUCTIONLivercirrhosisisoftencomplicatedbyhyperdynamiccirculation,whichischaracterizedbyadecreaseinarterialbloodpressureandperipheralvascularresistanceandanincreaseincardiacoutputandsplanchnicbloodnow[1].Thesehaemodynamicdisturbancesareproposedtocontributetothedevelopmelltofportalhypertension,retentionofsodiumandwater,ascitesformationandcorrelatewithprognosisoflivercirrhosis[2].Ithasbeensuggestedthatprimaryarterialvasodilationmayinducethishyperdynamiccirculation[3].Buttheunderlyingmec… 相似文献
425.
WANG ZeFeng 《中国科学:生命科学英文版》2015,(4):407-408
<正>One of the most exciting findings in RNA biology is the discovery of numerous circular RNAs(circ RNA)in mammalian genome.Once being considered as low abundance splicing byproducts,circ RNAs are surprisingly abundant 相似文献
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WU Qian) LI Rui) SUN Le) LIU Jing ) FANG Ai ) LIU Wen-Su ) LI Long ) YANG Meng) WANG Xiao-Qun) 《生物化学与生物物理进展》2016,(4):9
Changes of cerebral cortex size and brain volume have experienced evolutionary expansion across mammals, which is the cellular base of neuronal network complexity. The existence of cortex folding, allowing huge area of cortex to fit into a relatively small cranial space, is one of important evolutionary features in primate. The adult human CNS contains approximately 86.1 billion neurons and equal number of glial cells. Among which, human cerebral cortex consists of roughly 16.34 billion neurons. Based on algorithm analysis, approximately 3.86 million projection (excitatory/pyramidal) neurons are generated per hour during prenatal cortical neurogenesis in human. Such an incredible fast speed of neurogenesis suggests that human neocortex development requires strictly organized molecular regulations and cellular processes. Here we discuss the molecular and cellular characteristics of mammalian cerebral cortex expansion and the related disease. 相似文献
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