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21.
22.
Expression in Escherichia coli of chemically synthesized gene for the human immune interferon. 总被引:6,自引:0,他引:6 下载免费PDF全文
S Tanaka T Oshima K Ohsuye T Ono A Mizono A Ueno H Nakazato M Tsujimoto N Higashi T Noguchi 《Nucleic acids research》1983,11(6):1707-1723
A 454 base pair fragment of double stranded DNA consisting of a gene for a human immune interferon (hIFN-gamma), initiation and termination signals plus appropriate restriction endonuclease sites, was totally synthesized. The synthesis involved preparation of 62 oligodeoxyribonucleotides by rapid, solid phase procedures, and enzymatic ligation of the oligonucleotides. This synthetic gene was expressed in E. coli under the control of the lac UV5 promoter. The product has antiviral activity which was acid labile and completely neutralized by antiserum to hIFN-gamma but not by antiserum to hIFN-alpha or hIFN-beta. Molecular weight of hIFN-gamma produced by E. coli was estimated to be about 32,000 and 17,000 by gel filtration and SDS-polyacrylamide gel electrophoresis respectively. 相似文献
23.
Yasuhiro Noguchi Ineko Tawara Kaio Kondo Hideo Nigi Toshio Tanaka 《Primates; journal of primatology》1969,10(3-4):273-283
The electrocardiograms of 157 healthy Japanese monkeys (Macaca fuscata), covering a wide range of ages in both sexes, were recorded under light pentobarbital (Nembutal) anesthesia. Although results were generally similar to those reported for other macaque species, some quantitative differences were observed.The heart rate was about 160 per minute in all monkeys examined; the P-Q interval was 0.11±0.06 sec.; the duration of QRS was 0.04±0.01 sec.; the Q-T interval was 0.24±0.06 sec. The mean axis of QRS was +59° and the pattern of the QRS complex was qR type in most cases.The comparison with the human electrocardiogram shows that the heart rate ofM. fuscata is about twice that of man, while the P-Q, QRS, and Q-T intervals were about one-half of those found in human subjects. In the monkey, however, the P wave was sharp and the T wave flat.In order to estimate the effect of anesthesia on the electrocardiogram, the records of several monkeys before, during, and after intravenous administration of barbiturates were compared. Although some animals showed extrasystoles after barbiturate was administered, generally no essential changes were noted in the records, except for the retardation of the rate and proportional prolongation of intervals.This work was presented at the 10th Annual Meeting of the Primate Research Association held in Inuyama, March 13, 1966. 相似文献
24.
25.
Nucleotide sequence of the chromosomal gene coding for the aminoglycoside 6-adenylyltransferase from Bacillus subtilis Marburg 168 总被引:2,自引:0,他引:2
Gene aadK of Bacillus subtilis is 855 bp long and codes for aminoglycoside 6-adenylyltransferase. 相似文献
26.
The cell cycle block and lysis of an activated T cell hybridoma are distinct processes with different Ca2+ requirements and sensitivity to cyclosporine A 总被引:13,自引:0,他引:13
M Mer?ep P D Noguchi J D Ashwell 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(11):4085-4092
Stimulation of transformed T cells leads to both lymphokine secretion and inhibition of spontaneous growth. Studies performed with an Ag-specific T cell hybridoma demonstrated that growth inhibition is an early (within 1 h) manifestation of activation. Experiment in which extracellular Ca2+ was chelated or in which cyclosporine A was included indicated that activation-associated growth inhibition is a two-step process. The first phase is the establishment of a G1/S cell cycle block; it does not require extracellular Ca2+ and is not prevented by the addition of cyclosporine A. The second phase is cell lysis. It can be detected 4 to 6 h after activation, requires the presence of extracellular Ca2+, and is prevented when stimulation occurs in the presence of cyclosporine A. The observation that both Ca2+ depletion and cyclosporine A prevented IL-2 secretion at all time points indicates that the pathways leading to lymphokine secretion and the G1/S block diverge early in the course of the cellular response, and establish the cell cycle block as a distinct activation event with unique characteristics. 相似文献
27.
Souhei Sugita Misako Namima Toshitaka Nabeshima Koichi Okamoto Hiroshi Furukawa Yasuhiro Watanabe 《Neurochemistry international》1996,28(5-6):545-550
For the purpose of studying a role of immediate early genes in psychotomimetic-induced behavioral excitation, we experimentally enhanced the locomotor activity of mice by acute administration of phencyclidine and examined the expression and localization of the c-Fos-like and c-Jun-like immunoreactivities in brain regions. A single injection of phencyclidine (5.0 mg/kg, i.p.) significantly increased not only the locomotor activity but also the expression of c-Fos-like immunoreactivity in several brain regions, particularly in the parietal cortex, hippocampal dentate gyrus, piriform cortex and hypothalamus. Interestingly, the c-Fos-like immunoreactivity in the parietal cortex continued to increase for 1 week after the phencyclidine injection. These results indicate that phencyclidine, even injected only once, can induce the persistent expression of c-Fos or c-Fos-related protein(s) in the mouse brain, and also suggest the possibility that such a c-Fos expression may underlie the behavioral and/or psychotomimetic effects of phencyclidine. 相似文献
28.
Neutral red (NR) in the culture medium entered the vacuolesof a green alga, Micrasterias pinnatifida, at a higher rateat pH 8 than at pH 5. NR remained soluble in vacuoles of cellscultured at pH 5, while it precipitated and formed granulesin cells cultured at pH 8. The vacuoles of cells cultured atpH 8 contained fibrils, but those of cells cultured at pH 5did not. The amount of NR that entered the cells was markedlyreduced by the addition to the medium of nigericin at 10-5M,monensin at 10-5M, bafilo-mycin A1 at 10-5M, or ammonium chlorideat 50 mM. The formation of NR granules in vacuoles were stronglyinhibited and the disorganization of NR granules were acceleratedby the addition of nigericin at 10-5M, or bafilomycin A1 at10-5M to the culture medium. The possibility is discussed thatNR which enters vacuoles might become positively charged (NRH+)by protons brought into vacuoles by proton pumps and that NRH+might combine with some negatively charged macromolecules toform aggregates or granules. (Received April 18, 1996; Accepted May 27, 1996) 相似文献
29.
To clarify the way in which the light available for growth affectsrespiration in leaves of sun and shade plants, we examined therespiratory properties of mature leaves of Spinacia oleraceaL., a sun species, and of Alocasia macrorrhiza (L.) G. Don.,a shade species, that had been grown at various irradiances.In leaves of S. oleracea, the respiratory rates, on a dry massbasis, decreased with time during the night, and the higherwas the growth irradiance during the day, the higher was therespiratory rate. The marked decreases in the respiratory rateduring the night were accompanied by decreases in the concentrationof carbohydrates in the leaves. By contrast, the respiratoryrates of leaves of A. macrorrhiza were virtually constant throughoutthe night and the absolute rates were lower than those of S.oleracea even though the absolute value of the concentrationof carbohydrates and its decrease at night resembled to thosein S. oleracea. The maximum activities of respiratory enzymeswere also similar to those in S. oleracea. However, the leavesof A. macrorrhiza contained less soluble protein than thoseof S. oleracea. These results suggest that, in S. oleracea,the concentration of carbohydrates might determine the respiratoryrate while such is not the case in A. macrorrhiza. The lowerrespiratory rates in A. macrorrhiza might be due to a lowerdemand for ATP. (Received November 29, 1995; Accepted February 15, 1996) 相似文献
30.
Koike Hiroyuki; Yoneyama Koichi; Kashino Yasuhiro; Satoh Kazuhiko 《Plant & cell physiology》1996,37(7):983-988
Interactions of externally added plastoquinone (PQ) derivatives(PQ0-PQ3) with the photosystem II (PSII) acceptor side wereinvestigated in PSII membrane fragments prepared from spinachby measuring the photoreduction rates of PQ derivatives at variousPQ concentrations, and the following results were obtained. From the kinetic analysis, all the PQ derivatives (PQ0-PQ3)except PQ3 were shown to accept electrons at two sites (theQB site and the PQ site) as in the case of Synechococcus vulcanusPSII particles with benzoquinone derivatives [Satoh et al. (1995)Plant Cell Physiol. 36: 597]. Affinities of PQ derivatives at the QB site increased as thelength of the isoprene side chain got longer, while those atthe PQ site were not very much different for all the PQ derivativestested in this study. The inhibitory effect of DCMU was noncompetitive, and, therefore,the affinity of PQ3 for the PQ site was determined while thatfor the QB site could not be estimated presumably due to itsfairly high affinity to the site. Based on the results obtained using PQ derivatives, the mechanismof interaction of an authentic PQ, PQ9, at the QB site is discussed. (Received May 2, 1996; Accepted July 24, 1996) 相似文献