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71.
Do Quang Binh László E. Heszky Gabor Gyulai Anikó Csillag 《Plant Cell, Tissue and Organ Culture》1992,29(2):75-82
Cells of a 2-year-old suspension culture of rice (Oryza sativa L.), grown under 1.5% NaCl stress for 3 months, gave rise to plants through embryogenesis in different saline conditions. The high regeneration potential (59.6%) on salt-free medium decreased rapidly with increasing concentration of salt in the regeneration medium. At 1.25% NaCl, healthy shoots were developed in 14.9% of the cultures. Under 1.5% salt stress, embryo formation and embryo germination (6.1%) was observed but further development into plants was inhibited. Cells not pretreated with salt produced plants at a low frequency (2.6–4.2%) both in salt-free and low saline condition (0.75–1% NaCl). Cells pretreated for 3 months with 0.75% salt did not give rise to plants on all tested media. Plants regenerated from the salt-stressed cultures were transferred to soil and grew to maturity in a greenhouse.Abbreviations BA
6-benzyladenine
- CH
casein hydrolysate
- 2,4-D
2,4-dichlorophenoxyacetic acid
- NAA
1-naphthaleneacetic acid 相似文献
72.
The UDP-Glc:glycoprotein glucosyltransferase is a soluble protein of the endoplasmic reticulum. 总被引:7,自引:1,他引:6
N-linked oligosaccharides devoid of glucose residues are transiently glucosylated directly from UDP-Glc in the endoplasmic reticulum. The reaction products have been identified, depending on the organisms, as protein-linked Glc1Man5-9GlcNAc2. Incubation of right side-sealed vesicles from rat liver with UDP-[14C]Glc, Ca2+ ions and denatured thyroglobulin led to the glucosylation of the macromolecule only when the vesicles had been disrupted previously by sonication or by the addition of detergents to the glucosylation mixture. Similarly, maximal glucosylation of denatured thyroglobulin required disruption of microsomal vesicles isolated from the protozoan Crithidia fasciculata. Treatment of the rat liver vesicles with trypsin led to the inactivation of the UDP-Glc:glycoprotein glucosyltransferase only when proteolysis was performed in the presence of detergents. The glycoprotein glucosylating activity could be solubilized upon sonication of right side-sealed vesicles in an isotonic medium, upon passage of them through a French press or by suspending the vesicles in an hypotonic medium. Moreover, the enzyme appeared in the aqueous phase when the vesicles were submitted to a Triton X-114/water partition. Solubilization was not due to proteolysis of a membrane-bound enzyme. The enzyme could also be solubilized from C. fasciculata microsomal vesicles by procedures not involving membrane disassembly. About 30% of endogenous glycoproteins glucosylated upon incubation of intact rat liver microsomal vesicles with UDP-[14C]GLc could be solubilized by sonication or by suspending the vesicles in 0.1 M Na2CO3. These and previous results show that the UDP-Glc:glycoprotein glucosyltransferase is a soluble protein present in the lumen of the endoplasmic reticulum. In addition, both soluble and membrane-bound glycoproteins may be glucosylated by the glycoprotein glucosylating activity. 相似文献
73.
In the present work a linear model for a pair of antogonistic muscles is analysed. Each constituent muscle in this model is identical to ones considered previously (Stein and Ouztöreli, 1976). Analytical properties of the antagonistic muscles and dynamics of the system are described and some numerical results are discussed. The natural modes of the system are determined by a fourth order polynomial, which most commonly has one pair of conjugate complex roots and two negative real roots. The filtering of neural inputs through the active state properties of the muscle increases the order of the system to fifth order for these inputs.This work was partly supported by the National Scientific and Engineering Research Council of Canada Grant NRC-A4345 and by the Medical Research Council of Canada Grant MRC-MT-3307 through the University of Alberta 相似文献
74.
M. Namik Oğuztöreli 《Biological cybernetics》1982,44(1):1-8
In a recent work (Ouztöreli, 1980) a mathematical model for studying the neural activities in a vertebrate retina has been investigated, where the basic network contains five interconnected neurons: a receptor cell, a bipolar cell, a horizontal cell, an amacrine cell, and a retinal ganglion cell. More recently, in (Ouztöreli and O'Mara, 1980) the basic network has been extended to a larger network containing twelve neurons. In both of these works, the performances of the basic and extended models were discussed under different structural and processing conditions with constant inputs by using the results of one of our earlier work (Ouztöreli, 1979). In the present paper we investigate by simulations the responses of the basic retinal network to piecewise constant and periodic inputs. The step and frequency responses of the extended retinal network will be discussed in a forthcoming paper.This work was partially supported by the Natural Sciences and Engineering Research Council of Canada under Grant A-4345 through the University of alberta 相似文献
75.
Nineflavonoids: a dihydrochalcone,a flavone,four 3-methylflavonols,a flavanone, a 3-methylflavanonol and a flavan were isolated from the roots of Derris araripensis. Eight of these compounds are reported for the first time. Structures were established by spectral analysis and chemical degradation. 相似文献
76.
Electrophoretic patterns of acetylcholinesterase (acetylcholine hydrolase, EC 3.1.1.7) from rat erythrocyte were studied. The enzyme was solubilized by the following treatments: a) Triton X-100, b) sodium deoxycholate, or c) ultrasonic irradiation. When the erythrocyte membrane was solubilized by Triton X-100 at concentrations higher than 0.3%, by 10 mM sodium deoxycholate, or by ultrasonic irradiation for more than 5 min, a single band of acetylcholinesterase activity appeared in the gel. Two bands of activity were stained in the gel when the membrane was solubilized by Triton X-100 at concentrations between 0.1--0.2%, or by ultrasound for 5 min. Electrophoretic patterns of acetylcholinesterase from rats fed a fat-sufficient diet were similar to those for the enzyme from animals fed a fat-free diet. The recombination of lipids with the enzyme eluted from the gels confirmed the "phenotypic allosteric desensitization phenomenon". 相似文献
77.
Halil Erhan Eroğlu Ahmet Aksoy Ergin Hamzaoğlu Ümit Budak Sevil Albayrak 《Cytotechnology》2009,59(1):65-72
Helichrysum Mill. (Asteraceae) species have been used in folk medicine for thousands of years in the world. The in vitro cytogenetic
effects in human lymphocytes of nine Helichrysum taxa used in Turkey folk medicine were investigated. Blood samples were obtained from healthy donors, non-smoking volunteers,
which were incubated and exposed to increasing concentrations of methanol extracts of Helichrysum taxa (0.01, 0.05, 0.1, 0.5 and 1 mg/mL). The inhibitory effects of H. stoechas (L.) Moench subsp. barrelieri (Ten.) Nyman, H. armenium DC. subsp. armenium, H. armenium DC. subsp. araxinum (Kirp.) Takht., H. plicatum DC. subsp. plicatum, H. compactum Boiss. and H. artvinense P.H.Davis & Kupicha on the mitotic index and replication index indicate that these taxa can have genotoxic and mutagenic
effects. They should therefore not be used freely in alternative medicine although their antiproliferative activity may suggest
anticarcinogenic properties. Increase effects of H. stoechas subsp. barrelieri, H. armenium subsp. armenium, H. armenium subsp. araxinum, H. chasmolycicum P.H.Davis, H. plicatum subsp. plicatum, H. compactum and H. artvinense on the micronucleus rates showed that these taxa can have genotoxic and carcinogenic effects. 相似文献
78.
79.
Dinh Chuong Nguyen Duy Thanh Tran Thi Luu Luyen Doan Do Hwan Kim Nam Hoon Kim Joong Hee Lee 《Liver Transplantation》2020,10(8)
A novel hybrid of small core@shell structured CoSx@Cu2MoS4 uniformly hybridizing with a molybdenum dichalcogenide/N,S‐codoped graphene hetero‐network (CoSx@Cu2MoS4‐MoS2/NSG) is prepared by a facile route. It shows excellent performance toward the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline medium. The hybrid exhibits rapid kinetics for ORR with high electron transfer number of ≈3.97 and exciting durability superior to commercial Pt/C. It also demonstrates great potential with remarkable stability for HER and OER, requiring low overpotential of 118.1 and 351.4 mV, respectively, to reach a current density of 10 mA cm?2. An electrolyzer based on CoSx@Cu2MoS4‐MoS2/NSG produces low cell voltage of 1.60 V and long‐term stability, surpassing a device of Pt/C + RuO2/C. In addition, a Zn‐air battery using cathodic CoSx@Cu2MoS4‐MoS2/NSG catalyst delivers a high cell voltage of ≈1.44 V and a power density of 40 mW cm?2 at 58 mA cm?2, better than the state‐of‐the‐art Pt/C catalyst. These achievements are due to the rational combination of highly active core@shell CoSx@Cu2MoS4 with large‐area and high‐porosity MoS2/NSG to produce unique physicochemical properties with multi‐integrated active centers and synergistic effects. The outperformances of such catalyst suggest an advanced candidate for multielectrocatalysis applications in metal‐air batteries and hydrogen production. 相似文献
80.
Masahiko Saito Tomohiro Fukuhara Satoshi Kamimura Hiroyuki Ichikawa Hiroyuki Yoshida Tomoyuki Koganezawa Yutaka Ie Yasunari Tamai Hyung Do Kim Hideo Ohkita Itaru Osaka 《Liver Transplantation》2020,10(7)
Controlling the energetics and backbone order of semiconducting polymers is essential for the performance improvement of polymer‐based solar cells. The use of fluorine as the substituent for the backbone is known to effectively deepen the molecular orbital energy levels and coplanarize the backbone by noncovalent interactions with sulfur of the thiophene ring. In this work, novel semiconducting polymers are designed and synthesized based on difluoronaphthobisthiadiazole (FNTz) as a new family of naphthobisthiadiazole (NTz)–quaterthiophene copolymer systems, which are one of the highest performing polymers in solar cells. The effect of the fluorination position on the energetics and backbone order is systematically studied. It is found that the dependence of the solar cell fill factor on the active layer thickness is very sensitive to the fluorination position. It is thus further investigated and discussed how the structural features of the polymers influence the photovoltaic parameters as well as the diode characteristics and bimolecular recombination. Further, the polymer with fluorine on both the naphthobisthiadiazole and quaterthiophene moieties exhibits a quite high power conversion efficiency of 10.8% in solar cells in combination with a fullerene. It is believed that the results would offer new insights into the development of semiconducting polymers. 相似文献