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1.
Adventitious shoot primordia were formed on horseradish hairy root cultured in dark. Plantlet formation frequency from the primordia was higher than that from root fragments. Culture for 26 days provided the adventitious shoot primordia, which had the highest potential for plantlet formation (53% explants at 40 days). Benzyladenine supplementation in the dark caused primordium enlargement, but did not increase the number of primordia formed. After adventitious shoot primordia were encapsulated with calcium alginate, kinetin supplementation (2.0–4.0 M) increased the shoot formation frequency (65–80% explants at 20 days) in the light, but also promoted the undesirable formattion of multiple shoots. Supplementation with naphthaleneacetic acid (0.27–5.4 M) in the calcium alginate beads in light enhanced the root emergence from primordia without inhibition of plantlet formation when the encapsulated beads were put on the agar-medium without naphthaleneacetic acid.  相似文献   
2.
Makino  Wataru  Suzuki  Hiromichi  Otake  Yurie  Ban  Syuhei  Urabe  Jotaro 《Limnology》2023,24(3):151-159
Limnology - Chydorus sphaericus (O.F. Müller, 1776) (Crustacea: Cladocera) sensu stricto is distributed in Europe: C. sphaericus-like organisms in other regions represent a group of...  相似文献   
3.
张石宝  魏兆祥   《广西植物》1997,17(2):162-165
本文对观赏植物异色芋(ColocasiaheterochromaH.LietZ.X.Wei)在昆明栽培环境下的生物学特性进行总结,为商品化栽培异色芋提供了理论依据,为其分类也提供了一定的有益补充。结果表明:一年生植株不开花,根茎也不产生分枝;二年生植株开花率为73.6%,根茎平均分枝3.6条。异色芋3月上旬开始萌动,7月中旬抽花梗,8月上旬开花,11月份地上部分枯萎,因此在昆明异色芋生育期约260d。  相似文献   
4.
The sense of agency is the attribution of oneself as the cause of one’s own actions and their effects. Accurate agency judgments are essential for adaptive behaviors in dynamic environments, especially in conditions of uncertainty. However, it is unclear how agency judgments are made in ambiguous situations where self-agency and non-self-agency are both possible. Agency attribution is thus thought to require higher-order neurocognitive processes that integrate several possibilities. Furthermore, neural activity specific to self-attribution, as compared with non-self-attribution, may reflect higher-order critical operations that contribute to constructions of self-consciousness. Based on these assumptions, the present study focused on agency judgments under ambiguous conditions and examined the neural correlates of this operation with functional magnetic resonance imaging. Participants performed a simple but demanding agency-judgment task, which required them to report on whether they attributed their own action as the cause of a visual stimulus change. The temporal discrepancy between the participant’s action and the visual events was adaptively set to be maximally ambiguous for each individual on a trial-by-trial basis. Comparison with results for a control condition revealed that the judgment of agency was associated with activity in lateral temporo-parietal areas, medial frontal areas, the dorsolateral prefrontal area, and frontal operculum/insula regions. However, most of these areas did not differentiate between self- and non-self-attribution. Instead, self-attribution was associated with activity in posterior midline areas, including the precuneus and posterior cingulate cortex. These results suggest that deliberate self-attribution of an external event is principally associated with activity in posterior midline structures, which is imperative for self-consciousness.  相似文献   
5.
Otake  Yurie  Kagami  Maiko  Kuriyama  Takeo  Yoshida  Takehito 《Limnology》2019,20(1):29-38
Limnology - While induced defense of aquatic organisms against predators has been considerably studied by both laboratory and field research, our understanding is still limited about, for example,...  相似文献   
6.
Journal of Plant Research - Soybean (Glycine max) roots establish associations with nodule-inducing rhizobia and arbuscular mycorrhizal (AM) fungi. Both rhizobia and AM fungi have been shown to...  相似文献   
7.
Human neuroblastoma GOTO cell lines were established that stably express recombinant human lysosomal protective protein/cathepsin A (PPCA) cDNA by transfection. Intracellular cathepsin A (acid serine carboxypeptidase) activity increased four-fold compared with in those of the parent and mock-transfected cell lines. The immunoreactive 54 kDa precursor/zymogen and mature 32/20 kDa two-chain forms were produced in the cells. The amount of the latter form expressed in the GOTO cells was significantly larger than those in the PPCA-overexpressing CHO cell lines previously established. The intracellular proteins showed a typical lysosomal granular distribution and the glycosylated 54 kDa precursor was secreted into the culture medium without the addition of an alkalizing agent. The PPCA-overexpressing cell lines also retained the ability to differentiate bi-directionally as well as the parent cells; into neuronal cells on induction by dibutyryl cAMP in serum-free medium and into Schwannian cells on induction by bromodeoxyuridine. During the course of differentiation into neuronal and Schwannian cells, the intracellular cathepsin A activity further increased two and five times, respectively, which was associated with an increase in the expression of the 32/20 kDa two-chain form. The glycosylated precursor proteins were taken up via the mannose 6-phosphate receptors, and the cathepsin A, alpha-neuraminidase and beta-galactosidase (beta-Gal) activities deficient in the fibroblasts derived from a patient with PPCA deficiency (galactosialidosis) were restored. These results suggest that the bi-directional differentiation of GOTO cell lines stably expressing the recombinant human PPCA gene could be a model system for analyzing the functions of PPCA in peripheral neuronal cells and Schwannian cells as well as the recombinant PPCA could be a useful source for enzyme replacement therapy (ERT) for galactosialidosis patients.  相似文献   
8.
For evolution and maintenance of the social system of insect colonies, investment in the sterile caste should be adequately controlled in response to environmental cues. Recent developments using artificial diet rearing techniques have revealed an underlying mechanism of caste control in a gall-forming aphid, Tuberaphis styraci, which has a soldier caste in the second instar. Statistical analyses of field-collected galls detected a significant positive correlation between aphid density and soldier proportion in the natural colonies of T. styraci. Artificial diet experiments showed that soldiers are produced under crowded conditions. Detailed experiments demonstrated that soldiers are produced in a density-dependent manner rather than in a colony size-dependent manner. From these results, it was concluded that aphid density is the crucial cue that triggers soldier production in T. styraci. This study provides, to our knowledge, the first experimental demonstration of an environmental factor involved in aphid soldier differentiation.  相似文献   
9.
10.
In this study, the influences of initial settings, i.e. initial conformations, configurations and docking parameters, on docking results were investigated. The conformations used in the study were generated by the CAMDAS program. After the conformational search calculations, five structures were selected from the conformer groups according to their conformation energies and root mean square deviations against crystal structures; for example, the lowest energy conformer, as well as the closest and farthest conformers to the crystal structure, was retrieved. Several docking parameter settings were used (default, high speed, generating 50 poses). In this study, docking calculations were conducted using the GOLD, eHiTS, AutoDock, AutoDock vina, FRED and DOCK programs. The success rates of GOLD, eHiTS and FRED were better than those of AutoDock, AutoDock vina and DOCK. The docking results using the farthest conformations were worse than those obtained using other conformations, indicating that some conformation search for the ligand molecule should be performed before the docking calculations.  相似文献   
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