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61.
Intervention studies have shown that the adaptation of fat oxidation to fat intake, when changing the dietary fat content, is not abrupt. This study was conducted to measure the time course of adaptation of oxidation rates to increases in the fat content of the diet, when feeding subjects at energy balance. Twelve healthy, non-obese males and females (age: 26 +/- 2, BMI: 21.4 +/- 0.5, habitual fat intake: 29 +/- 1% energy) consumed a low-fat diet for 6 days (days 1-6) followed by a high-fat diet for 7 days (day 7-13). Days 5-9 and day 13 were spent in a respiration chamber. After adjusting energy intake to 24h energy expenditure on day 5, subjects were in energy balance (range -0.15 to +0.23 kJ/day) on days 6-9 and day 13. Fat balance was zero on day 6 but became positive after changing to the high-fat diet (1.06 +/- 0.15, 0.75 +/- 0.15, and 0.55 +/- 0.14 MJ/day for days 7, 8, and 9 respectively, p. < 0.05), reaching a new balance on day 13, 7 days afterwards. Thus, in case of energy balance, lean subjects are capable of adjusting fat oxidation to fat intake within 7 days, when dietary fat content is increased.  相似文献   
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A 44-year-old woman with stage IV non-Hodgkin's lymphoma (NHL) of the left ovary is described. She had an extended hysterectomy and bilateral salpingo-ophorectomy and thereafter received six courses of combination chemotherapy (cyclophosphamide, adriamycin, vincristine and predonisolone; CHOP). The patient is well with no evidence of recurrence at 12 months after surgery. The literature on primary ovarian lymphoma is reviewed.  相似文献   
65.
Meat ‘reddening’ by bacteria was observed in chilled beef. To identify the reddening bacteria, isolates were inoculated onto beef and the changes in CIE L*a*b* values monitored. As a result, two Pseudomonas spp., including Pseudomonas fragi which is commonly observed in raw meat, were selected and identified as reddening bacteria. The reddening was coincidentally occurred with the appearance of slime, and the increase in thiobarbituric acid-reactive substances (TBARS) was simultaneously suppressed. In myoglobin-containing nutrient broth, it is shown spectroscopically that P. fragi converted metmyoglobin into deoxymyoglobin. It was concluded that the meat reddening was due to the formation of deoxymyoglobin, induced by the very-low-oxygen tension brought about by Pseudomonad’s oxygen consumption: This oxygen depletion simultaneously suppressed TBARS increase.  相似文献   
66.
Hydrogasification of a bituminous and a brown coal was carried out at 1273 K in the presence of nickel catalyst. The action of the catalyst during gasification was investigated using a scanning electron microscope. Contrary to what is found with steam gasification, most of the catalyst particles were spherical, due to the higher temperature. Some particles made pits and disappeared into the char matrix and others agglomerated with each other increasing the diameter of the particles significantly. Although the action of the catalyst on a brown coal was essentially similar to that on a bituminous coal, the catalyst was more homogeneously distributed over the char surface from the brown coal.  相似文献   
67.
Ibogaine (Endabuse) is a psychoactive indole alkaloid found in the West African shrub, Tabernanthe iboga. This drug interrupts cocaine and amphetamine abuse and has been proposed for treatment of addiction to these stimulants. However, the mechanism of action that explains its pharmacological properties is unclear. Since previous studies demonstrated differential effects of psychotomimetic drugs (cocaine and methamphetamine) on neuropeptides such as neurotensin (NT), the present study was designed to determine: (1) the effects of ibogaine on striatal, nigral, cortical, and accumbens neurotensin-like immunoreactivity (NTLI); (2) the effects of selective dopamine antagonists on ibogaine-induced changes in NT concentrations in these brain areas; and (3) the effects of ibogaine pretreatment on cocaine-induced changes in striatal, nigral, cortical and accumbens NTLI content. Ibogaine treatments profoundly affected NT systems by increasing striatal, nigral, and accumbens NTLI content 12 h after the last drug administration. In contrast, NTLI concentrations were not significantly increased in the frontal cortex after ibogaine treatment. The ibogaine-induced increases in NTLI in striatum, nucleus accumbens and substantia nigra were blocked by coadministration of the selective D1 receptor antagonist, SCH 23390. The D2 receptor antagonist, eticlopride, blocked the ibogaine-induced increase in nigral NTLI, but not in striatum and nucleus accumbens. Ibogaine pretreatment significantly blocked the striatal and nigral increases of NTLI resulting from a single cocaine administration. Whereas many of the responses by NT systems to ibogaine resembled those which occur after cocaine, there were also some important differences. These data suggest that NT may contribute to an interaction between ibogaine and the DA system and may participate in the pharmacological actions of this drug.  相似文献   
68.
提出了一种基于平滑冲击驱动原理的精密定位直线微工作台.通过采用微小强磁铁作为摩擦元件,减小了由摩擦元件磨损而产生的摩擦力的变化,从而提高了微工作台的稳定性.设计制作了微工作台样机,并对精密定位工作台的动态特性和静态特性进行了实验研究.结果表明,微工作台体积小(20mm×10 mm×3 mm),可实现6 nm的精确定位,最高驱动速度可达5.4 mm/s,最大行程可达20 mm.  相似文献   
69.
The decomposition of CCl2F2 to CO2 and accompanying halogen fixation by a CaO based material was studied. To improve the low reactivity of CaO, a consequence of its low surface acidity, transition metal oxides were added. Impregnation of metal acetylacetonate followed by removal of the ligand under vacuum was found to be an effective method. This method resulted in the formation of carbonaceous species and the reduction of metal oxide to metal, both of which were thought to initiate the decomposition reaction. The reactivity of these materials (MOx(a)/CaO-vac) was found to be in the following order: M = Ni > Cu > V = Fe > Mn > Co > Ca. In particular, nickel supported on CaO was most effective for the decomposition of CCl2F2. During the preparation, nickel oxide was reduced to the metal phase. CCl2F2 was decomposed to CO2 with a small amount of CO, and halogens were fixed as CaFCl, without significant deactivation at 723 K.  相似文献   
70.
Two-way satellite time and frequency transfer (TWSTFT) is one of the main techniques used to compare atomic time scales over long distances. To both improve the precision of TWSTFT and decrease the satellite link fee, a new software-defined modem with dual pseudo-random noise (DPN) codes has been developed. In this paper, we demonstrate the first international DPN-based TWSTFT experiment over a period of 6 months. The results of DPN exhibit excellent performance, which is competitive with the Global Positioning System (GPS) precise point positioning (PPP) technique in the short-term and consistent with the conventional TWSTFT in the long-term. Time deviations of less than 75 ps are achieved for averaging times from 1 s to 1 d. Moreover, the DPN data has less diurnal variation than that of the conventional TWSTFT. Because the DPN-based system has advantages of higher precision and lower bandwidth cost, it is one of the most promising methods to improve international time-transfer links.  相似文献   
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