Author Keywords: Vegetation; natural covering; green covering; field survey; urban area 相似文献
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1.
1-O-Octadecyl-2-acetyl-sn-glycerol 3-phosphate (octadecylacetyl-GP) and its deacetylation product were used as a model of phosphatidic acid and its lyso derivatives, respectively. The binding, transbilayer movement, and intermembranous transport, which should be related to its metabolism in guinea pig peritoneal polymorphonuclear leukocytes, were studied. The albumin extraction procedure (Tokumura, A., Tsutsumi, T., Yoshida, J., and Tsukatani, H. (1990) Biochim. Biophys. Acta 1044, 91-100) was used for studying the transbilayer movement of [3H]octadecylacetyl-GP. The binding, translocation, and metabolism of octadecylacetylglycerol, a dephosphorylated product of octadecylacetyl-GP, in polymorphonuclear leukocytes were also investigated for comparison. The translocation of octadecylacetyl-GP was dependent on temperature, but not on its concentration (in the range of 1-100 nM). The rate of translocation of octadecylacetyl-GP was much slower than that of octadecylacetylglycerol. Treatment of polymorphonuclear leukocytes with N-ethylmaleimide did not affect the translocation of octadecylacetyl-GP. These results suggest that the transbilayer movement of octadecylacetyl-GP is driven by a diffusion process, not by a carrier protein. From these findings, the process of translocation of octadecylacetyl-GP is concluded to be a rate-limiting step in its metabolic conversion to triglyceride, phosphatidylethanolamine, and phosphatidylcholine. 相似文献
2.
Y Tsutsumi S Kakumu T Wakita K Yoshioka T Ishikawa 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(6):2389-2393
To evaluate the relative immunogenicity of and the mechanism for production of antibody to hepatitis B core (HBc) and hepatitis B e (HBe) Ag, we investigated the in vitro anti-HBc and anti-HBe production by PBMC from 25 patients with chronic active hepatitis (CAH) (15 with HBeAg and 10 with anti-HBe) and 12 ASC (5 with HBeAg and 7 with anti-HBe) in the presence of PWM, rHBcAg, or purified HBeAg. PWM-stimulated culture produced higher titer anti-HBc (mean % inhibition +/- SD = 73 +/- 23%, p less than 0.001) than anti-HBe (34 +/- 17%). HBcAg stimulation elicited greater anti-HBc response (43 +/- 26%, p less than 0.001) than did HBeAg for anti-HBe (26 +/- 12%). Both HBcAg and HBeAg induced equivalent anti-HBe response. Anti-HBc production in response to HBcAg was higher in CAH patients (51 to 55%) than in asymptomatic carriers of hepatitis B surface Ag (22 to 28%) irrespective of their HBeAg/anti-HBe status, but reflecting serum anti-HBc value. Similar findings were noted in HBeAg-stimulated anti-HBe production for the two patient groups. In HBeAg- and anti-HBe-positive CAH, HBcAG-stimulated anti-HBc production was similar in T (1.4 x 10(6)) and B (0.6 x 10(6)) cells coculture, and B cells (2 x 10(6)) alone culture. However, in the HBeAg-stimulated culture, T plus B cells produced significantly higher titer anti-HBe than B cells alone did. These results indicate that HBcAg has a relatively higher immunogenicity in terms of antibody production as compared to HBeAg. Furthermore, HBcAg was shown to function as a T cell-dependent and -independent Ag, whereas HBeAg is T cell-dependent during chronic hepatitis virus B infection in man. 相似文献
3.
Shin-ichiro Kurimoto Kyoko Suzuki Mamoru Okasaka Yoshiki Kashiwada Olimjon K. Kodzhimatov Yoshihisa Takaishi 《Phytochemistry letters》2012,5(4):729-733
Five new eudesmane- (1–5), two new guaiane- (6 and 7) and one new germacrane-type (8) sesquiterpene lactone glucosides were isolated from the H2O-soluble fraction of the roots of Ferula varia. Their structures were elucidated by extensive spectroscopic analyses. The absolute configuration of 1 was determined by modified Mosher's method. 相似文献
4.
Winged bean Kunitz chymotrypsin inhibitor (WCI) is encoded by a multigene family and accumulation of its mRNA is restricted in mid-maturation stage seeds and tuberous roots. In this paper, we analyzed the accumulation of mRNA derived from each WCI gene using a novel method: sequence-specific termination analysis. The results demonstrated that the accumulation of each WCI mRNA was differentially regulated in winged bean plants. 相似文献
5.
Sakayu Shimizu Keiko Inoue Yoshiki Tani Hideaki Yamada 《Biochemical and biophysical research communications》1981,103(4):1231-1237
The preparation of highly purified medium chain acyl-CoA synthetase (Acid: CoA ligase, AMP-forming (EC 6.2.1.2)) from the cell extracts of is described. The enzyme is inducibly formed in the cells of the microorganism, when it is grown with butyrate as a major carbon source. The purified enzyme is homogeneous on disc gel electrophoresis. Its molecular weight is approximately 142,000, and it is possibly composed of 4 identical subunits of approximately 37,000 molecular weight and has isoelectric point of 4.3. The enzyme catalyzes the stoichiometric conversion of butyrate and CoA to butyryl-CoA in the presence of ATP and Mg2+. It also activates fatty acids with carbon chain lengths of 3 to 5 well, but is inactive toward fatty acids with carbon chain lengths of more than 6. The enzyme is sulfhydryl dependent and inactivated by silver and mercury compounds. 相似文献
6.
Increased dithiothreitol-insensitive,type 2 angiotensin II receptors in selected brain areas of young rats 总被引:3,自引:0,他引:3
1. Angiotensin II receptors have been studied by quantitative autoradiography in selected brain areas of young (2-week-old) and adult (8-week-old) rats. 2. In young rats, angiotensin II receptors were present in brain areas which did not express receptors in the adult brain, such as thalamic nuclei, cortical areas, and the cerebellum. 3. Young rats had more angiotensin II receptors in the subfornical organ than adult rats. In the inferior olive, the number of angiotensin receptors in young animals was 10 times higher than that in adult rats. Angiotensin II binding in the inferior olive was insensitive to incubation in the presence of dithiothreitol. 4. Conversely, the number of angiotensin II receptors in the nucleus of the solitary tract was lower in young rats compared to adults. Incubation in the presence of dithiothreitol resulted in a more than 90% inhibition of angiotensin II binding in the nucleus of the solitary tract. 5. Our results indicate the presence of two types of angiotensin II receptor in brain, one sensitive (type 1) and one insensitive (type 2) to the reducing agent dithiothreitol. 6. The expression of type 2 angiotensin II receptors, insensitive to dithiothreitol, is more marked in young rats, indicating a role for this type of angiotensin receptors in brain development. 相似文献
7.
8.
Tadahisa Katayama Akio Ishii Tetsuo Hayashi Jun-ichiro Tsutsumi 《Journal of thermal biology》1993,18(5-6):571-576
1. 1. Three kinds of field survey on different scales were carried out in Fukuoka City in summer to examine the relationship between the quantity of vegetation and air temperature.
2. 2. The field of the largerst scale measurement is across the city.
3. 3. Several parks and shrines of various sizes in the city were selected as other measurement areas.
4. 4. The most detailed measurements are carried out in a park with an area of 1.25 ha located in a down town area of the city.
5. 5. Though the amount of vegetation is expressed in a unique way in each survey, it is clearly found that the greener it is, the lower is the air temperature.
9.
Yoshiki Sakata 《Bioscience, biotechnology, and biochemistry》2013,77(6):355-361
The velocity of the α-β transition was measured in two cases, i.e., when α-crystals stayed in the saturated aqueous solution, and when they were left to stand in an air-bath at various temperatures ranging from 20° to 100°C. And it was deduced from the results of the measurement that this transition is due to the recrystallization of α-crystals into the β-form on the inner surfaces of the crystal and in the bulk of the solution, and the transition on the inner surfaces will be dominant, especially at the initial stage of the transition. 相似文献
10.