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排序方式: 共有1213条查询结果,搜索用时 31 毫秒
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Yue Chen Huan Wang Taibai Xu Peng Zhou Junsong Pan Weiwei She Weiwei Zhang 《Phyton》2023,92(4):1059-1070
Fruit spine is an important quality trait of cucumber. To better understand the molecular basis of cucumber spine development and function, RNA-Seq was performed to identify differentially expressed genes (DEGs) in fruit spines of different development stages, namely, 8 days before anthesis (SpBA8), anthesis (SpA) and 8 days after anthesis (SpAA8). Stage-wise comparisons obtained 2,259 (SpBA8 vs. SpA), 4,551 (SpA vs. SpAA8), and 5,290 (SpBA8 vs. SpAA8) DEGs. All the DEGs were classified into eight expression clusters by trend analysis. Among these DEGs, in addition to the Mict, Tril, CsTTG1, CsMYB6, NS, and Tu genes that have been reported to regulate fruit spine formation, we found that the CsHDG11, CsSCL8, CsSPL8, CsZFP6 and CsZFP8 may also be involved in spine development in cucumber. Our study provides a theoretical basis for further research on molecular mechanisms of spine development in cucumber. 相似文献
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Many soft bodied coelenterates are highly deformable or contractile. In the absence of hard skeletal elements, the epithelia are subjected to mechanical forces which cause a wide range of structural changes in the component epithelial cells. What kinds of structural change occur and how are the cells adapted to them? These questions are addressed with reference to cell surface area, cell membranes, cell junctions and epithelial cilia.
相似文献15.
Sharon B. Emerson 《Journal of evolutionary biology》1991,4(4):671-678
Differences in forelimb length between male and female frogs and between amplexing and non-amplexing males have been interpreted to be the results of sexual selection on forelimb length. The causal feature of the forelimb that has been posited to cause such selection is the observation that non-amplexing males attempt to disrupt breeding by prying amplexing males from females. A biomechanical model of forelimb function suggests that total length per se may not be the most appropriate measure to use. There are more functionally significant aspects of forelimb morphology, such as lever arm lengths, that should influence amplexing ability and may make measures of overall forelimb length misleading. This example highlights the relevance of functional analysis to current questions in evolutionary biology that rely on postulated roles for morphological structures under selection. 相似文献
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Summary Using techniques for enhanced microtubular preservation, including albumin pretreatment (Gray, 1975), occipital cortex of rats was studied electron microscopically at various ages of development. A close structural relationship was seen between microtubules, sacs of SER and the postsynaptic thickening in primordial spines and with the dense plate material of spine apparatuses. Stereoscopic preparations in addition show a more complicated substructure than previously described for the plate. Microtubules may contribute to the formation of the plate of the spine apparatus which in turn is associated with the postsynaptic thickening of the mature spine. Possible functional correlates are discussed.Dr. L.E. Westrum is an affiliate of the CDMRC at the University of Washington and a recipient of a Burroughs-Wellcome (USA) — Wellcome Trust (U.K.) Research Travel Grant. The research was also supported in part by NIH Grants NS 09678, NS 04053 (NINCDS) and DE 04942 (NIDR), DHHS 相似文献
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Dorian Salin Pierre-Jean Arnoux Kambiz Kayvantash Michel Behr 《Computer methods in biomechanics and biomedical engineering》2016,19(14):1578-1582
In the field of biomechanics, the offer of models which are more and more realistic requires to integrate a physiological response, in particular, the controlled muscle bracing and the reflexes. The following work aims to suggest a unique methodology which couples together a sensory and motor loop with a finite element model. Our method is applied to the study of the oscillation of the elbow in the case of a biceps brachial stretch reflex. The results obtained are promising in the purpose of the development of reactive human body models. 相似文献
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Whole-body fields were tested for their efficacy in preventing the osteopenia caused by tail suspension in mice. The fields had fundamental frequencies corresponding to the upper range of predicted endogenous impact-generated frequencies (0.25–2.0 kHz) in the long bones. Three distinct whole-body EMFs were applied for 2 weeks on growing mice. Structural, geometric, and material properties of the femora, tibiae, and humeri of suspended mice were altered compared to controls. Comparison of suspended mice and mice subjected to caloric restriction indicates that the changes in caloric intake do not explain either the suspension or the field-induced effects. In agreement with past studies, rather, unloading appears to cause the suspension effects and to be addressed by the EMFs. The EMF effects on bone properties were apparently frequency dependent, with the lower two fundamental frequencies (260 and 910 Hz) altering, albeit slightly, the suspension-induced bone effects. The fields are not apparently optimized for frequency, etc., with respect to therapeutic potential; however, suspension provides a model system for further study of the in vivo effects of EMFs. © 1995 Wiley-Liss, Inc. 相似文献
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