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281.
Recovering useful hydrocarbons from sewage sludge using zirconia-supporting iron oxide catalysts was investigated. Zirconia has activity for decomposing water molecules to generate active oxygen and hydrogen species. These oxygen species spill over to the surface of iron oxide and react with hydrocarbons to produce oxygen-containing organic chemicals such as acetone. Thus, zirconia-supporting iron oxide catalyst has two kinds of active sites on zirconia and on iron oxide. Sewage sludge was hydrothermally liquefied at 573 K in advance, yielding black water containing various hydrocarbons, to enhance the contact of reactant molecules with the catalysts. It was found that the hydrocarbons in the black water converted well to a mixture containing primarily acetone without any carbonaceous residue over zirconia-supporting iron oxide catalysts under the conditions of one atmospheric pressure and superheating steam atmosphere. Furthermore, it was confirmed that acetone was produced continuously from the sewage-derived black water over the catalysts using a bench scale flow reactor.  相似文献   
282.
Expression of lymphokine genes including interleukin 2 (IL-2), interleukin 3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon gamma (IFN-g), tumor necrosis factor (TNF) and lymphotoxin (LT) were sequentially monitored in peripheral blood mononuclear cells by Northern blot analysis after stimulation with phytohemagglutinin (PHA). The pattern of the expression of lymphokine genes following PHA stimulation as categorized into two types. Type 1 was characterized by rapid appearance of mRNA and by early maximum accumulation. Type 2 was characterized by the prolonged expression and late peak time. Lymphokines including IL-2, IL-3 and GM-CSF belong to type 1 and IFN-g, TNF and LT belong to type 2. Since lymphokines in type 1 are known to act on hematopoiesis in a stimulatory manner, whereas type 2 show an inhibitory action, this sequential expression of lymphokines following mitogen stimulation may reflect some biological feedback mechanism.  相似文献   
283.
Nephrosclerosis is the most typical and widespread renal manifestation of hypertension and can be judged as the pathological hallmark of essential hypertension. Nephrosclerosis is an important and frequent cause of progressive renal disease, however, information in the literature on the risk of developing renal failure in the course of essential hypertension is sparse. Traditionally, nephrosclerosis was thought to result from glomerular ischemia. Alternatively, glomerular sclerosis in hypertension may result from glomerular hyperperfusion or hypertension. Studies in experimental models of renal disease have identified a promising intervention with either Ca antagonists or angiotensin-converting enzyme inhibitors. Application of these therapies to patients with nephrosclerosis should await the results of careful clinical trials.  相似文献   
284.
The role of leukocytes in the pathogenesis of cerebrovascular disease, in particular, cerebral ischemic disease has recently become a focus of research. Several studies have reported that a positive correlation between increased functional activities of neutrophils and the risk of cerebral ischemic disease. Granulocyte colony-stimulating factor (G-CSF) is known to be not only a granulocyte proliferating factor but also a potent activator of mature neutrophils. In this study, we measured the serum G-CSF levels in 143 patients with cerebrovascular diseases and in 100 patients with other diseases, using our established enzyme-linked immunosorbent assay (ELISA) for G-CSF The minimal detection level was 20 pg/ml G-CSF. In patients with cerebral infarction, G-CSF could be detected in 18.3% and in patients with cerebral hemorrhage, it could be detected in 9.8% of analyzed samples. On the other hand, 6% of the patients with other diseases had measurable levels of G-CSF. The differences among these three groups were statistically significant according to the chi 2 test (p < 0.01). Our findings that there was a significantly high frequency of elevated levels of G-CSF among patients with cerebrovascular diseases, may indicate that the action of G-CSF as a potent activator of neutrophils plays some role in the occurrence of cerebrovascular disease, in particular, cerebral infarction.  相似文献   
285.
IL-18 is a product of macrophages and with IL-12 strikingly induces IFN-gamma production from T, B, and NK cells. Furthermore, IL-18 and 1L-12 synergize for IFN-gamma production from Th1 cells, although this combination fails to affect Th2 cells. In this study, we show that IL-12 and IL-18 promptly and synergistically induce T and B cells to develop into IFN-gamma-producing cells without engaging their Ag receptors. We also studied the mechanism underlying differences in IL-18 responsiveness between Th1 and Th2 cells. Pretreatment of T or B cells with IL-12 rendered them responsive to IL-18, which induces cell proliferation and IFN-gamma production. These IL-12-stimulated cells had both high and low affinity IL-18R and an increased IL-18R mRNA expression. In particular, IL-12-stimulated T cells strongly and continuously expressed IL-18R mRNA. However, when T cells developed into Th1 cells after stimulation with anti-CD3 and IL-12, they lowered this IL-12-induced-IL-18R mRNA expression. Then, such T cells showed a dominant response to anti-CD3 by IFN-gamma production when they were subsequently stimulated with anti-CD3 and IL-18. In contrast, Th2 cells did not express IL-18R mRNA and failed to produce IFN-gamma in response to anti-CD3 and IL-18, although they produced a substantial amount of IFN-gamma in response to anti-CD3 and IL-12. However, when Th1 and Th2 cells were stimulated with anti-CD3, IL-12, and IL-18, only the Th1 cells markedly augmented IFN-gamma production in response to IL-18, suggesting that IL-18 responsiveness between Th1 and Th2 cells resulted from their differential expression of IL-18R.  相似文献   
286.
We constructed a stable recombinant Marek's disease virus type 1 (rMDV1) expressing the fusion protein (F) of Newcastle disease virus (NDV) by inserting the coding sequence within the US10 gene of MDV1 by homologous recombination and designated this as rMDV1-US10L(F). The NDV-F protein was significantly expressed under control of the SV40 late promoter in cultured cells infected with the rMDV1. To examine the protective efficacy of the rMDV1, specific pathogen-free (SPF) chickens were vaccinated with rMDV1 at one-day-old. Almost all birds (> 95%) were protected from NDV challenge via intramuscular, ocular, intranasal and intratrachial routes at 4 weeks after vaccination. The rMDV1 showed 100% protection against virulent MDV1 challenge in SPF chickens. Antibody responses against NDV-F and MDV1 antigens were observed at least up to 11 weeks after immunization. When the sera from chickens vaccinated with the rMDV1 were examined for the presence of anti-NDV-F antibody on the day of NDV challenge, the vaccinated bird group which did not survive from NDV challenge were found to show lower antibody titers than the surviving group. The rMDV1 also provided sufficient protection against NDV and MDV1 challenges in commercial chickens with maternal antibodies against NDV-F and MDV1 antigens.  相似文献   
287.
The pathogenesis of pelvic endometriosis has been studied by using scanning electron and light microscopy, observing the surface structure of bluish lesions obtained from 26 patients during laparotomy. Paraffin sections included another 17 tissue samples of endometriosis, based on immunohistochemical responses to epithelial membrane antigen, keratin and vimentin. Ultrastructurally, the surface epithelial cells could not be detected in 13 out of 17 pelvic peritoneal endometriosis samples. In one case in which the surface peritoneal cells were seen histologically to dip into the subperitoneal stroma, many surface peritoneal infoldings were observed, and ciliated cells were detected at the edge of these infoldings. Ovarian endometriosis was composed of three types of cells, none of which had any cilia. These findings were observed in continuity with adjacent normal mesothelial cells. No characteristic structure of the endometrial surface was observed for the bluish lesion, but the gland surface of endometriosis located in the subperitoneal stroma initially had ciliated cells. The immunoreactions in both the columnar mesothelial cells with surface peritoneal infoldings and the glands of endometriotic tissues were similar to those of normal endometrial glands, but different from those of normal mesothelial cells. Pelvic endometriosis might originate by a process of metaplasia from the pelvic peritoneum.  相似文献   
288.
This paper describes superconducting magnets coupled with two kinds of disk-type MHD generators. One is coupled with a disk generator in the closed-cycle MHD experimental facility FUJI-1. The other is for a full-scale disk MHD generator. These are split-pair magnets. In the magnet for the FUJI-1 facility, a unique structure which supports the coils against the electromagnetic force has been fabricated and the magnet has been operating stably. During MHD power generation experiments, an induced voltage across the terminals of the coil was measured. A magnitude of the Faraday current in the generator was calculated from this induced voltage. A possible construction of magnetics for a full-scale disk MHD generator is indicated. It is suggested that a high performance of the generator (output power density of 0.3-1 GW/m3) can be obtained with high magnetic field up to 10 T.  相似文献   
289.
EB-cured PCS fibers were heat-treated at 1273–1673 K under a reduced pressure of 1.33 Pa, and subsequently they were exposed to 1773 K in air. The thermal stability and oxidation resistance of the fibers were investigated through TG, XRD analysis, specific resistivity measurement, SEM observation and tensile tests. The oxidation rates at initial stage are thought to be strongly dependent upon the microstructure of the fibers in the as-heat treated state and the presence of water vapor. Incomplete ceramization and the occurrence of active-oxidation during heat-treatment yielded poor oxidation resistance to the fibers. The oxidation caused the grain growth of SiC, drop of resistivity and degradation of strength. The oxidation of the fibers was retarded at later stage. The fibers heat-treated at 1573 K had high strength and high oxidation resistance.  相似文献   
290.
Male Slc:Wistar, Std:Wistar, and Slc:F344/N rats had good acquisition of the conditioned avoidance response (CAR), while that of the male Slc:Wistar/ST, Jcl:Wistar, and Crj:Wistar rats was bad. Reserpine-induced impairment (RII) in CAR was observed 2-72 h after administration of dopaminergic (DAergic) agents in male Slc:Wistar rats. Amitriptyline (5-80 mg/kg, P.O.), imipramine, desipramine, cis-dosulepine, and trans-dosulepine at dose of 40 mg/kg, P.O. showed no antagonism against RII in CAR 20-23 h after reserpine injection (1 mg/kg, S.C.). However, the atypical antidepressive agents sibutramine (5-10 mg/kg, P.O.), bupropion (40 mg/kg, P.O.), and nomifensine (10-40 mg/kg, P.O.) exhibited antagonism against RII in CAR. The calcium channel antagonists flunarizine, nimodipine, and KP-840 at dose of 10 and 100 mg/kg, P.O., the cerebral improving agent indeloxazine (20-80 mg/kg, P.O.), the anticholinergic agent atropine (5-40 mg/kg, P.O.), 5-hydroxy-L-tryptophan (5-HTP) (40 mg/kg, I.P.), a precursor of 5-hydroxytryptamine (5-HT), and (+/-)-threo-dihydroxyphenylserine [(+/-)-threo-DOPS] (20-200 mg/kg P.O.), a norepinephrine (NE) precursor, showed no antagonism against RII in CAR. The DAergic agents methamphetamine (5 mg/kg, P.O.) and amantadine (50-250 mg/kg, P.O.), L-DOPA (200 mg/kg, P.O.), and the DAergic D1/D2 receptor agonist apomorphine (0.1-1 mg/kg, S.C.) showed marked antagonism against RII in CAR. Although the DAergic D1-receptor agonist KF-38393 (0.3-30 mg/kg, I.P.) and the DAergic D2-receptor agonist quinpirole (0.3-10 mg/kg, I.P.) induced only a weak recovery of RII in CAR when they were administered alone, in contrast to a potent synergistic recovery of RII in CAR, which was observed when SKF-38393 (1 mg/kg, I.P.) and quinpirole (1 mg/kg, I.P.) were administered together. These results suggest that the DAergic nervous system rather than the adrenergic or 5-HT nervous system is involved in RII in CAR, and that both the DAergic D1- and D2-mediated nervous systems play important roles in this process.  相似文献   
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