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61.
ATPase, especially the Ca2$-dependent enzyme, in the chromatinfraction isolated from nuclei of pea seedlings was activatedby bovine brain calmodulin and by protein that was judged tobe calmodulin from its Ca2$-dependent activation of NAD kinase.This calmodulin-dependent ATPase activity was blocked by calmodulin-specificinhibitors. (Received July 11, 1983; Accepted October 24, 1983) 相似文献
62.
A determinate scheme for modeling the mechanical effects of muscle contractions in a musculoskeletal system, using the direct-stiffness method of structural analysis, is described. Data concerning skeletal geometries, connective tissue passive mechanical properties, and muscle lines-of-action and cross-sectional areas are incorporated to make the model specific for studies of muscle actions in the human trunk. Several illustrative examples of model trunk responses to muscle contractions are presented and discussed. 相似文献
63.
The association of absorbed aluminium (Al) with nuclei in Alaskapea roots was shown by zonal centrifugation of isolated nuclei.In nuclei, 73% of the total incorporated Al was detected inthe DNP fraction. Furthermore, Al in DNP was found to be boundspecifically to DNA by gel filtration of dissociated DNP. (Received March 19, 1977; ) 相似文献
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65.
Summary The asymmetric hydrolysis of N-acetyl-1-methyl-3-phenypropylamine (MPAc) by microorganisms was investigated. Various bacteria belonging to the genera Bacillus, Agrobacterium, Corynebacterium, Arthrobacter, Brevibacterium, Cellulomonas, Acinetobacter, Nocardia and Rhodococcus showed this hydrolysing activity and yielded (S)-1-methyl-3-phenylpropylamine (MPPA). Using washed cells of N. erythropolis IAM 1440, 15.1 mg/ml of (S)-MPPA was formed, with a 38.8% conversion yield and high stereoselectivity (97.9% enantiomeric excess), in an organic solvent-water diphase system. The same (S)-amine and (S)-1-phenylethylamine were also produced in good yields from the valeryl and isovaleryl derivatives of MPPA, and N-acetyl-1-phenylethylamine, respectively. 相似文献
66.
Stereospecific Reduction of Ethyl 2′ -Ketopantothenate to Ethyl D-(+)-Pantothenate with Microbial Cells as a Catalyst
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Michihiko Kataoka Sakayu Shimizu Yukiko Doi Hideaki Yamada 《Applied microbiology》1990,56(11):3595-3597
A novel enzymatic process for the synthesis of D-(+)-pantothenic acid through the asymmetric reduction of the 2′ -ketopantothenate ester is described. Candida macedoniensis AKU 4588 was found to convert ethyl 2′ -ketopantothenate (80 mg/ml) almost specifically to ethyl D-(+)-pantothenate (>98% enantiomeric excess), with a molar yield of 97.2%. 相似文献
67.
Inphase interactions among EEG signals recorded using eight electrodes were investigated. The inphase interaction parameters are presented in two ways: (1) matrix form in which the number of inphase interactions are tabulated; and (2) histogram in which the number of inphase interactions are plotted pair-wise between two sites as a function of phase delays in milliseconds. The highest number of interactions occurs between 0 and 8 ms in normal brains. The values of interaction parameters are enhanced by various activities. For example, inphase interaction parameters increase in the motor area in the right hemisphere if the EEG is recorded during repeated left fist clenching. Inphase interactions are drastically altered by the presence of a tumor. We studied the inphase interactions of the EEG of a patient having an occipital tumor. The interaction parameters are greatly diminished in this area, indicating a severe impairment of neuronal communications between both hemispheres in the occipital region. The confidence limits of the changes in inphase interaction parameters during fist clenching are tested statistically using the Student's t test. The test shows that the interaction parameters increase, in general, with 1–5% confidence limits in respective cortex areas as a result of fist clenching. 相似文献
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69.
Increase in Alkaline Phosphatase Activity in Cucumber Roots during Calcium Starvation 总被引:1,自引:0,他引:1
Alkaline phosphatase activity in cucumber roots increased withcalcium deficiency. However, acid phosphatase was scarcely affectedby the treatment. Re-addition of calcium not only suppressedthe continuous increase in alkaline phosphatase activity butalso reduced the already formed activity. Alkaline phosphatase activity increased with a deficiency ofcalcium, phosphate, minor elements and iron in this order. Eithercycloheximide or actinomycin D completely suppressed the increasein the activity caused by calcium deficiency. (Received April 16, 1981; Accepted July 17, 1981) 相似文献
70.
Hideaki Yamada Toru Nagasawa Haruyuki Ohkishi Bunsei Kawakami Yoshiki Tani 《Biochemical and biophysical research communications》1981,100(3):1104-1110
Synthesis of D-cysteine from 3-chloro-D-alanine and hydrogen sulfide is catalyzed by highly purified 3-chloro-D-alanine hydrogen chloride-lyase from . The synthetic reaction proceeds optimally at pH 8.5, as a function of enzyme concentration and incubation time. The enzymatically synthesized D-cysteine was isolated from the large scale reaction mixture and identified by physicochemical means. 相似文献