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41.
Genetic susceptibility plays an important role in the development of schizophrenic psychoses, and the neural maldevelopment hypothesis is suggested by neuropathological and neuroimaging findings. We investigated the association between a null mutation in the ciliary neurotrophic factor (CNTF) gene and functional psychoses including schizophrenia and schizoaffective disorder. The frequency of mutant allele was significantly increased in patients with schizoaffective disorder, but not in those with schizophrenia in comparison with controls. The CNTF null mutation resulting in CNTF deficiency may confer potential susceptibility to schizoaffective disorder.  相似文献   
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The atomic-bridging type negative oxide charge in SiO2 is investigated using the Fe-contaminated (001) surface of n-type Si wafers. The investigation is done on the basis of a chemical analysis and a method in which the frequency-dependent alternating current (AC) surface photovoltage (SPV) is measured. At room temperature, an AC SPV appears and gradually increases, saturating after approximately one day (with an Fe concentration on the Si surface of 4.0 × 1013 atoms/cm2). The AC SPV eventually becomes inversely proportional to frequency except at very low frequencies (< 10 Hz) corresponding to weak or strong inversion, indicating that the negative Fe induced oxide charge appears in the form of a (FeOSi) network. Also, in Fe-contaminated n-type Si(001) surfaces thermally oxidized at between 550 and 650 °C for 60 min, strong inversion is unquestionably observed, proving that the (FeOSi) network survives and that most of the added Fe has segregated into the region closest to the surface of the thin SiO2 film. At 850 °C and/or for long oxidation times, the AC SPV decreases and ultimately disappears, implying that the (FeOSi) network has collapsed and may have changed into Fe2O3. A model for the metal-induced negative oxide charge in the conventional oxide charge diagram is proposed.  相似文献   
44.
The nitroimidazole-related hypoxic radiosensitizer, pimonidazole (Pmz) was encapsulated in liposome composed of dipalmitoylphosphatidylcholine, cholesterol and dipalmitoylphosphatidylglycerol (molar ratio = 1:1:0.2; diameter = 112.9 nm), and the radiosensitization was evaluated in human melanoma cells HMV-II. Cell proliferation was examined by WST-8 assay after X-ray irradiation in the presence of liposomal Pmz or free-Pmz under hypoxic conditions. On 7th day after X-ray irradiation of 5 Gy, cell proliferation decreased more markedly in the administration of liposomal Pmz than free-Pmz at equivalent Pmz doses. Chromatin fragmentation or nuclear condensation was observed in liposomal Pmz-treated HMV-II cells. Radiosensitization was enhanced dose-dependently along with Pmz amounts of 250-2000 microM contained in liposomal Pmz. Intracellular uptake was more abundant for liposomal Pmz for 60-240 min than for free-Pmz. Thus liposomal Pmz has a potential to overcome radiation resistance in hypoxia, owing to enhanced intracellular uptake by melanoma cells.  相似文献   
45.
The photoassisted degradation (HPLC-UV absorption), dehalogenation (HPLC-IC) and mineralization (TOC decay) of the flame retardants tetrabromobisphenol-A (TBBPA) and tetrachlorobisphenol-A (TCBPA) were examined in UV-irradiated alkaline aqueous TiO2 dispersions (pH 12), and for comparison the parent bisphenol-A (BPA, an endocrine disruptor) in pH 4–12 aqueous media to assess which factor impact most on the photodegradative process. Complete degradation (2.7–2.8 × 10−2 min−1) and dehalogenation (1.8 × 10−2 min−1) of TBBPA and TCBPA occurred within 2 h of UV irradiation, whereas only 45–60% mineralization (2.3–2.7 × 10−3 min−1) was complete within 5 h for the flame retardants at pH 12 and ca. 80% for the parent BPA. Factors examined in the pH range 4–12 that impact the degradation of BPA were the point of zero charge of TiO2 particles (pHpzc; electrophoretic method), particle or aggregate sizes of TiO2 (light scattering), and the relative number of OH radicals (as DMPO–OH adducts; ESR spectroscopy) produced in the UV-irradiated dispersion. Dynamics of BPA degradation (2.0–2.4 × 10−2 min−1) were pH-independent and independent of particle/aggregate size, but did correlate with the number of OH radicals, at least at pHs 4 to 8–9, after which the rates decreased somewhat at pH > 9 with decreasing adsorption owing to Coulombic repulsive forces between the very negative TiO2 surface and the anionic forms of BPA (pKas ca. 9.6–11.3), even though the number of OH radicals continued to increase at the higher pHs.  相似文献   
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Recently, it has been said that deterioration of concrete structures occurs due to migration of ions, such as Cl or Na+, through concrete. In addition, some electrochemical methods which control migration properties through concrete, like desalination or re-alkalization, are becoming more important. However, the mechanisms of ion migration, in electric fields, through concrete are not well understood. Moreover, the effects of mineral admixtures, such as fly ash, silica fume and ground-granulated blast furnace slag on ion migration through concrete have not been closely investigated. From this viewpoint, for the evaluation of mineral admixtures, the properties of chloride ion migration through mortar containing fly ash, silica fume and ground-granulated blast furnace slag have been investigated.  相似文献   
48.
We examined the influence of probe‐tissue distance on the relationship between the deep tissue absorption coefficient and the spatial profile of light intensity by Monte Carlo simulation and in vivo experiments, using noncontact spatially resolved near‐infrared spectroscopy (SRS). These results suggest that noncontact SRS can be reliably used for noncontact measurement of the absorption coefficient and oxygen saturation of deep tissues. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
49.
Treatment of storm-water runoff may be necessary before discharge to surface waters. In urban areas, space constraints limit selection of conventional treatment systems, and alternative systems are needed. This research program involves design and laboratory testing of a small footprint nonproprietary detention basin which consists of pipes and box culvert sections with a specialized inlet and outlet system. This system can be placed below grade near the roadway section as part of the conventional drainage system and does not require additional right-of-way. A mathematical model, based entirely on hydraulic principles, is developed to estimate particle removal efficiency of the rectangular detention basin for the treatment of storm-water runoff by extending ideal horizontal tank theory under the condition in which water level is varied. A physical model was built in 1/5 scale to measure particle removal performance and validates the conceptual model. Experiments were performed for steady inflow conditions with different inflow rates, durations, and suspended sediment concentrations. Measured time series outflow suspended sediment concentrations and particle removal efficiency compare well with calculated results from the conceptual model. The outflow particle-size distribution can also be estimated using the conceptual model.  相似文献   
50.
Conventional anticonvulsants can be classified into three types according to their mechanisms of action: (1) those which act on voltage-dependent Na+ channels such as phenytoin, (2) those which act on T-type Ca2+ channels such as ethosuximide, and (3) those which enhance GABA receptor-mediated inhibitory neurotransmission such as phenobarbital or valproate. However, recent studies on experimental models of epilepsy have suggested that the neural mechanisms underlying experimental epileptogenesis are based on: (1) increments in cellular excitability through changes in the function of Na(+)- or Ca2+ channels, (2) desinhibition or inhibition failure, and (3) enhancement of excitatory amino acid receptor-mediated excitatory neurotransmission. These findings might help us to understand the recently developed anticonvulsants and vice versa. In this review, newly developed anticonvulsants are categorized according to the neural mechanisms underlying epileptogenesis, particularly actions on excitatory and inhibitory neurotransmission.  相似文献   
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