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71.
Genetic Manipulation of the Extent of Desaturation of Fatty Acids in Membrane Lipids in the Cyanobacterium Synechocystis PCC6803 总被引:1,自引:0,他引:1
Wada Hajime; Gombos Zoltan; Sakamoto Toshio; Murata Norio 《Plant & cell physiology》1992,33(5):535-540
The desA gene of the cyanobacterium, Synechocystis PCC6803,is responsible for the desaturation of fatty acids at the 相似文献
72.
To investigate the reactions involved in the biosynthesis of vindoline from tabersonine, the bioconversion products formed when the latter compound was fed to cell suspension cultures of Catharanthus roseus were isolated and characterized. Two biotransformation products of tabersonine were isolated and shown to be lochnericine, which is formed by epoxidation of tabersonine at positions 14, 15, and lochnerinine, the 11-methoxylation product of lochnericine. The bioconversion ratio of the main biotransformation product, lochnericine, reached a value of 80.6% within three days. 相似文献
73.
James H. Resau Kosaku Sakamoto John R. Cottrell Eric A. Hudson Stephen J. Meltzer 《Cytotechnology》1991,7(3):137-149
Organ explant culture models offer several significant advantages for studies of patho-physiologic mechanisms like cell injury, secretion, differentiation and structure development. Organs or small explants/slices can be removed in vivo and maintained in vitro for extended periods of time if careful attention is paid to the media composition, substrate selection, and atmosphere. In the case of human tissues obtained from autopsy or surgery, additional attention must be paid to the postmortem interval, temperature, hydration, and cause of death. Explant organ culture has been effectively utilized to establish outgrowth cell cultures and characterize the histiotypic relationships between the various cell types within an organ or tissue.J. Resau is a visiting scientist at the NCI-LMO-DCE in Frederick, MD 21702, U.S.A.K. Sakamoto is a visiting scientist from the Department of Surgery, Gunma University School of Medicine, Maebashi, Japan 相似文献
74.
75.
Organomercurial-volatilizing bacteria in the mercury-polluted sediment of Minamata Bay, Japan. 总被引:2,自引:2,他引:0 下载免费PDF全文
A total of 4,604 bacterial strains isolated from the sediments of Minamata Bay and nearby low-level-mercury stations (control stations) were screened for the ability to volatilize mercury from inorganic and organic mercurial compounds. The strains that volatilize mercury from several kinds of organomercurials were found only in the sediments of Minamata Bay. 相似文献
76.
An extra idic(15p)(q11) chromosome in Prader-Willi syndrome 总被引:4,自引:0,他引:4
Using a nonfluorescent AT-specific oligopeptide antibiotic, Distamycin A, on DAPI fluorescent banding of human chromosome (DA-DAPI) as described by Schweizer et al. (1978), we have detected an additional idic(15p) chromosome in a patient with typical Prader-Willi syndrome. On the basis of the evidence available in previous studies and of our own present results, we suspect that the fundamental genetic error in the syndrome is not caused by a chromosome aberration but by a gene aberration on chromosome 15. 相似文献
77.
This study was designed to investigate the oxytocin (OT) specific binding receptors in 20,000 x g pellets of nonpregnant, first trimester and term human myometria. The receptor analysis was done using the lower uterine segment at term and the lower portion of the anterior uterine body in nonpregnant and first trimester subjects, and no difference was found in the myometrial receptor concentrations in the various uteri. The mean +/- S.D. values of the receptor dissociation constants were 3.33 +/- 0.50, 2.71 +/- 1.03 and 1.87 +/- 0.30 nM and the number of binding sites was 0.30 +/- 0.10, 0.50 +/- 0.10 and 1.50 +/- 0.50 pmol/mg protein at each stage studied, indicating that the gestational increase of uterine sensitivity to OT is due to the increase in myometrial OT binding sites as well as its binding affinity. Further, myometrial OT binding before and after the onset of labor was studied and a marked decrease in total myometrial OT binding was noticed; 35.6 +/- 13.0% before and 20.2 +/- 5.0% after. This decrease was thought to be due to the decrease in the number of binding sites from 1.50 +/- 0.50 to 0.74 +/- 0.21 pmol/mg protein after the onset of labor (p less than 0.01). No changes were found in the dissociation constants. Thus it seems that OT and its receptor coupling triggers labor or is involved in the early steps of labor. 相似文献
78.
As a continuation of previous papers [Biopolymers (1976) 15 , 879; (1978) 17 , 1508], the low-frequency dielectric relaxation of DNA solutions was studied with a four-electrode cell and the simultaneous two-frequency measurement. Below a critical concentration, the dielectric relaxation time agrees with the rotational relaxation time estimated from the reduced viscosity and is almost independent of DNA concentration Cp, and the dielectric increment is proportional to Cp. The critical concentration is approximately 0.02% of DNA for molecular weight Mr 2 × 106 and 0.2% for Mr 4.5 × 105 in 1 mM NaCl. Dielectric relaxations are compared for samples before and after deproteinization, and the protein contamination is found to have a minor effect on the dipole moment of DNA. The effect of a mixed solvent of water and ethanol on the dielectric relaxation of DNA is well interpreted in terms of changes in viscosity and the dielectric constant of the solvent, assuming that the relaxation arises from rotation of the molecule with a quasi-permanent dipole due to counterion fluctuation. 相似文献
79.
K Yamamoto K Itoh S Yoshida K Saito Y Sakamoto A Matsuda T Saito T Kuzuya 《Endocrinologia japonica》1979,26(2):255-261
Using B-mode ultrasonography, an attempt was made to measure the volume of extraocular muscles and retrobulbar fat in 31 patients (62 orbits) with Graves' disease. None of the patients had exophthalmometric measurements greater than 21 mm or had eye symptoms. The mean value of muscle volume of Graves' patients was significantly larger than that of normal controls (6.48 +/- 2.70 cm3 and 3.25 +/- 1.30 cm3, respectively, p less than 0.001). All of the patients had extraocular muscle swelling, although 2 of them had no extraocular muscle change for their unilateral eye. The extraocular muscle volume increased as the degree of the proptosis increased. The fat volume tended to increase in parallel with the degree of the proptosis. In the Graves' group with obvious proptosis (Hertel reading: 19--21 mm), the fat volume increased more significantly than in any other group. The ratio of extraocular muscle volume to retrobulbar fat volume was significantly higher in Graves' disease, but it did not increase as the degree of the proptosis increased. A significant correlation between proptosis and muscle volume plus fat volume was observed. No significant difference of the extraocular muscle volume was observed between the patients untreated and treated with antithyroid drugs. The data show a uniform enlargement of the extraocular muscles in Graves' disease and also suggest an involvement of increased retrobulbar fat volume in a group of obvious exophthalmos. The degree of the proptosis is in aclose proportion ot the quantitative change of the orbital soft tissue. 相似文献
80.