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排序方式: 共有503条查询结果,搜索用时 31 毫秒
1.
Ishida Takuya Uehara Yoshitoshi Ikeya Tohru Haraguchi Takashi F. Asano Satoshi Ogino Yohei Okuda Noboru 《Limnology》2020,21(3):403-413
Limnology - Controlling phosphorous (P) loads from rice fields is important for the conservation of aquatic ecosystems, in part because P is relatively concentrated at its sources. Recently, winter... 相似文献
2.
To elucidate the protective effects of glutathione against iron-induced peroxidative injury, changes in the hepatic glutathione metabolism were studied in chronically iron-loaded mice. When the diets of the mice were supplemented with carbonyl iron, iron deposition occurred primarily in the parenchymal cells of the liver. In addition, expiratory ethane production was elevated, suggesting an enhancement in lipid peroxidation. In iron-loaded mice, the total hepatic glutathione contents were higher (6.21 +/- 0.53 mumol/g wet wt.) than in control mice (4.61 +/- 0.31 mumol/g wet wt.), primarily due to an increase in the reduced glutathione contents. The value of oxidized glutathione was also higher (98.5 +/- 8.1 nmol/g wet wt.) than in the controls (60.8 +/- 9.5 nmol/g wet wt.), and the ratio of oxidized glutathione to total glutathione increased. The excretion rate of glutathione from the hepatocytes in iron-loaded mice also increased. These observations suggest that chronic iron-loading of mice stimulates lipid peroxidation and oxidation of glutathione and that peroxidized molecules may be catabolized using reduced glutathione. 相似文献
3.
Masafumi Abe Naoya Nakamura Shirou Fukuhara Takamasa Hayashi Keiki Kawakami Kenkichi Kita Toshifumi Kinoshita Toyoro Ohsato Haruki Wakasa 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):107-113
A new human acute lymphoblastic leukemia (ALL) cell line, designated HBL-3, was established from the bone marrow of a patient
with non-T-ALL. The HBL-3 cell line expressed B4 (CD 19), BA-1 (CD 24) and HLA-DR antigens, but not surface immunoglobulin
(SIg) or cytoplasmic immunoglobulin (CIg). The cell line lacked the common acute lymphoblastic leukemia antigen (CALLA) and
antigenic markers characteristic of T-cell and myeloid cell lineages. The HBL-3 cells had structural rearrangements of both
the homologous chromosome 9s, including a translocation with chromosome 1 which has been reported in a patient with common
ALL. The cell line had rearranged immunoglobulin heavy chain genes but retained germ-line κ light chain genes and germ-line
T-cell receptorβ- and γ-chain genes. The HBL-3 cell line was strongly positive for terminal deoxynucleotidyl transferase (TdT). These findings
indicate that the HBL-3 cell line is derived from the earliest B-cell committed to B-cell lineage. 相似文献
4.
M. J. Avison S. R. Gullans T. Ogino G. Giebisch 《The Journal of membrane biology》1988,105(3):197-205
Summary Addition of glucose or the nonmetabolizable analogue -methyl-d-glucoside to rabbit proximal tubules suspended in a glucoseand alanine-free buffer caused a sustained increase in intracellular Na+ content (+43±7 nmol · (mg protein)–1) and a concomitant but larger decrease in K+ content (–72±11 nmol· (mg protein)–1). A component of the net K+ efflux was Ba2+ insensitive, and was inhibited by high (1mm) but not low (10 m) concentrations of the diuretics, furosemide and bumetanide. The increase in intracellular Na+ content is consistent with the view that the increased rates of Na+ and water transport seen in the proximal tubule in the presence of glucose can be attributed (at least in part) to a stimulation of basolateral pump activity by an increased [Na+]
i
. 相似文献
5.
Comparison of plasma prostanoid levels in the human cord artery in normal and fetal distressed deliveries 总被引:1,自引:0,他引:1
Prostaglandin E2 (PGE2), thromboxane B2 (TXB2; as a stable metabolite of TXA2), prostaglandin F2 alpha (PGF2 alpha) and 6-keto-PGF1 alpha (as a stable end product of prostacyclin) have been measured by using specific radioimmunoassay in the plasma of the cord artery immediately after delivery before the cord was clamped. Plasma prostanoid concentrations in normal deliveries (n = 8, as controls) were 24.8 +/- 2.6 (PGE2), 246.8 +/- 37.0 (TXB2), 122.2 +/- 13.3 (PGF2 alpha) and 82.1 +/- 7.7 (6-keto-PGF1 alpha) respectively (pg/ml, mean +/- s.e). On the other hand, in fetal distressed deliveries showing continuous bradycardia (n = 6), they increased significantly to 275.4 +/- 20.1 (PGE2), 948.6 +/- 102.5 (TXB2), 218.0 +/- 21.4 (PGF2 alpha) and 1498.6 +/- 298.4 (6-keto-PGF1 alpha) respectively (pg/ml, mean +/- s.e, p less than 0.005). However, both PGF2 alpha/PGE2 and TXB2/6-keto-PGF1 alpha ratios declined significantly from 4.70 +/- 0.33 to 0.68 +/- 0.05 and from 3.07 +/- 0.37 to 0.68 +/- 0.12 respectively (mean +/- s.e, p less than 0.005) in the fetal distressed group compared with those of the controls. From these results, it may be concluded that the cord artery, which is known as the patent source for the production of PGE2 and prostacyclin, did exert a sufficiently strong reaction to overcome the undesirable haemodynamic changes to maintain the fetal well-being in utero. 相似文献
6.
High-resolution proton magnetic resonance spectroscopy was used to analyze human cerebrospinal fluid obtained from patients with several neurological problems. The major metabolites measured included glucose, lactate, glutamine, citrate, inositol, acetate, creatine, creatinine, beta-hydroxybutyrate, alanine, and pyruvate. A drug vehicle, propylene glycol, was also measured. Alterations in the cerebrospinal fluid of these metabolites provided information concerning metabolism of the brain. Magnetic resonance spectroscopy offered a simple and rapid means of assessing these and other exogenous and endogenous compounds in diseases affecting the nervous system. 相似文献
7.
What causes the aphid 28S rRNA to lack the hidden break? 总被引:1,自引:0,他引:1
8.
Organic-Solvent-Tolerant Bacterium Which Secretes Organic-Solvent-Stable Lipolytic Enzyme 总被引:4,自引:1,他引:3 下载免费PDF全文
A bacterial strain which could be grown in a medium containing organic solvents and which could secrete lipolytic enzyme was isolated. The stability of the lipolytic activity of the supernatant of the culture increased significantly in the presence of organic solvents such as toluene, cyclohexane, ethanol, and acetone. 相似文献
9.
An EMBL4 recombinant phage which encodes one of the full length of the aphid ribosomal DNA has been isolated from the aphid genomic library. Determination of the complete nucleotide sequence of the aphid 18S rRNA gene revealed that it is 2469 bp with a G + C content of 59%. The aphid 18S rRNA gene studied here is the longest and has the highest G + C content among the 18S rRNA genes examined so far. Evidence provided by the S1 nuclease assay suggests that the aphid 18S rRNA gene examined in this study is not a pseudogene containing an insertion sequence. Based on the nucleotide sequence of the 18S rRNA gene, we constructed a presumed secondary-structure model of the aphid 18S rRNA. In the aphid 18S rRNA, the eucaryote-specific E21 and 41 region are supposed to be longer and more complex than the counterparts of other 18S rRNA. 相似文献
10.