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Unrolling due to blue light (B) irradiation of the second leavesdetached from 8-day-old rice (Oryza saliva L.) seedlings wassimilar to that reported previously for nondetached leaves.The effect of B was counteracted by irradiation with red light(R). The counteracting effect of R was reversed by subsequentirradiation with far-red light (FR). When the detached leaf was irradiated with B passed througha 1-mm-wide slit 5, 8, 10, 12 or 15 mm from the leaf tip, irradiation10 mm from the leaf tip was the most effective. The effect of a 1 mm-wide-B irradiation 10 mm from the leaftip was counteracted by a 1 mm-wide-R irradiation at the sameposition, but not by irradiations at the other points. The counteractingeffect of R was reversed by a 1 mm-wide-FR irradiation at thesame position. This suggests that the excitation or the reactionof the B photoreceptor(s) is affected directly by the PFR formof phytochrome. The dose-response curve for the unrolling caused by B showeda simple Bunsen-Roscoe relation without two peaks, which differsfrom that for the phototropism in Avena caused by B. (Received August 21, 1980; Accepted December 20, 1980) 相似文献
44.
The physiological action of CCC for leaves of Kyoho grapes wasstudied. Leaves from the lower to upper positions of the primaryshoots and (primary) lateral shoots showed uneven photosyntheticactivities with peaks. The photosynthetic activity of each leaffrom both shoots was increased by treatment with CCC, whereasrespiratory activity was not affected with CCC. In the primaryshoots, CCC treatment increased the contents of chlorophylla and b in the leaves, but in the lateral shoots only chlorophyllb contents were increased. Dry weights of the leaves from thelateral shoots increased with CCC, but those of leaves locatedin the vicinity of nodes bearing the fruit clusters varied slightlyor were almost the same as the dry weight of non-treated leaves.Leaf thickness was increased by CCC and paralleled the variationin dry weight. The leaf area was decreased by CCC. (Received April 19, 1980; ) 相似文献
45.
Elongation of oligonucleotides in the 3'-direction with activated mononucleotides and their analogs using RNA ligase. 总被引:4,自引:4,他引:0
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E Ohtsuka T Miyake K Nagao H Uemura S Nishikawa M Sugiura M Ikehara 《Nucleic acids research》1980,8(3):601-610
P1-Adenosine 5'-P2-2',3'-ethoxymethylidene nucleosides [A(5')ppN(Em)] from four common nucleosides have been prepared and used for single addition of nucleotides to elongate oligonucleotide chains in the 3'-direction in RNA ligase reaction. U-U-C, T-U-C and A-C-C were used as acceptors. Structural dependence in these acceptors was found to be smaller compared to joining reactions between oligonucleotides. Adenosine analogs including 8-bromo-, 2'-fluoro-, 2'-azido-, 8,2'-O-cyclo-, 8,2'-S-cyclo-adenosine, arabinosyladenine and 2'-deoxyadenosine were added to the 3'-end of A-C-C by adenylation chemically followed by joining with RNA ligase. Symmetrical 5'-pyrophosphates of 8-bromo-, 2'-fluoro- and 2'-azido-adenosine were not recognized as donor substrates. 相似文献
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Summary Active transport of orthophosphate byChlorella ellipsoidea was observed at 25 °C under fluorescent light, about 3 klux. Influx and efflux of phosphate, and extra- and intracellular phosphate concentrations were measured in order to assess phosphate permeability in the cells. The permeability ranged from 10–3 to 10–4
mlQ/mg cell min (or 10–7 to 10–8cm/sec). 相似文献
48.
We studied how value for instrumental action is discounted by predicted effort and delay. The monkeys were trained to perform instrumental trials that required a bar release when a visual target changed from red-to-green. There were two trial conditions. In delay trials, after the monkeys performed one instrumental trial correctly a reward was delivered 0–7 seconds later. In work trials, the monkeys had to perform 0, 1, or 2 additional instrumental trials to obtain a reward. The lengths of trials in delay matched the time it took to complete work trials. The length of delay or number of trials was indicated by a visual cue presented throughout the trial. Our hypothesis was that the monkeys would all show temporal discounting of reward in the delay trials, and that in the work trials the monkeys’ performance might reflect an additional cost due to working. The error rate increased linearly as remaining cost increased for all 8 monkeys. For 4 monkeys the error rate was significantly larger in work trials than in delay trials (effort sensitive monkeys). For the other 4 monkeys there was no significant difference in error rate (effort insensitive monkeys). Since the error rate has an inverse relation with value for action, these results suggest that value is discounted hyperbolically by effort as well as by delay. Error rates generally increased as the testing sessions progressed and the total reward accumulated (i.e., effect of reward devaluation). The relative impact of delay and effort on error rates was reasonably stable within subjects. Thus, within the monkey population there seems to be a significant dichotomy in the sensitivity governing whether working is more costly than waiting, possibly arising from a constitutional or genetic trait. 相似文献
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Fujishiro Miyuki Yahagi Shoichi Takemi Shota Nakahara Mio Sakai Takafumi Sakata Ichiro 《Molecular biology reports》2021,48(7):5513-5518
Molecular Biology Reports - Pyridoxine (PN), one of the vitamers of vitamin B6, plays an important role in the maintenance of epidermal function and is used to treat acne and rough skin. Clinical... 相似文献