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91.
Our previous studies showed the possibility that activation of the antioxidative function alleviates various oxidative damages, which are related to lifestyle diseases. Results showed that, low-dose X-ray irradiation activated superoxide dismutase and inhibits oedema following ischaemia-reperfusion. To alleviate ischaemia-reperfusion injury with transplantation, the changes of the antioxidative function in liver graft using low-dose X-ray irradiation immediately after exenteration were examined. Results showed that liver grafts activate the antioxidative function as a result of irradiation. In addition, radon inhalation enhances the antioxidative function in some organs, and alleviates alcohol-induced oxidative damage of mouse liver. Moreover, in order to determine the most effective condition of radon inhalation, mice inhaled radon before or after carbon tetrachloride (CCl(4)) administration. Results showed that radon inhalation alleviates CCl(4)-induced hepatopathy, especially prior inhalation. It is highly possible that adequate activation of antioxidative functions induced by low-dose irradiation can contribute to preventing or reducing oxidative damages, which are related to lifestyle diseases.  相似文献   
92.
Nanoparticles are synthesized efficiently from zinc electrode by microwave plasma in liquid. The nanoparticles synthesized from alcohol resulted in pure zinc particles in the shape of spheres or hexagonal cylinders with a production rate of 3.3 g/h, and energy consumption of 267 J/mg for 1 mg. Whereas the nanoparticles synthesized in pure water are composed of Zn and ZnO. The Zn reacts with water through heat or the passage of time to become ZnO, releasing hydrogen gas. An upper disk placed 1 mm away from the electrode along with the bubbles generated simultaneously with the plasma ignition plays a key role in the synthesis of nanoparticles.  相似文献   
93.
The degradation characteristics of n- and p-channel polysilicon thin-film transistors (TFTs) under circuit operation were investigated by using CMOS inverter circuits consisting of n-channel TFTs with a lightly doped drain (LDD) structure and p-channel TFTs with a single-drain (SD) structure. A new test element made it possible to separately evaluate the degradation characteristics of each type of TFT during CMOS inverter operation. In regard to n-channel LDD TFTs, the device degradation is mainly caused by accumulated dc stress under the condition that the gate voltage is near the threshold voltage and the high drain voltage, i.e., the drain-avalanche hot-carrier (DAHC) stress condition. In p-channel SD TFTs, the device degradation is caused by the mutual interaction between DAHC stress and negative-bias-temperature (NBT) stress. Hole injection due to NBT stress is accelerated by DAHC-stress-induced trapped electrons under inverter-circuit operation. The effect is thus enhanced not only by the increase in the number of hole injections but also by the increase in the number of electron injections. It was found that the device characteristics of p-channel TFTs are more rapidly degraded as the rising time of the input pulse becomes shorter. This degradation is caused by the transient increase in the number of hot electrons, which are generated when holes are emitted from the trap states when the p-channel TFTs are turned off.   相似文献   
94.
A 47-year-old woman was admitted to our hospital with a giant spinal arteriovenous malformation (AVM) causing heart failure and thoracic myelopathy. Angiography revealed that the spinal AVM had multiple feeding vessels branching from the 5th through 12th intercostal arteries. The drainage vein flowed to the azygos vein and superior vena cava. The AVM destroyed the 7th thoracic vertebra. The cardiac output was 16.7l/min and the shunt ratio was 64% before treatment. Embolization with cyanoacrylate was performed because the operation was considered to be associated with a significant risk of paraplegia and organ ischemia. The cardiac output decreased to 11.6l/min and the shunt ratio was reduced to 32%. After embolization the patient demonstrated no symptoms of either heart failure or sensory deficits. During embolization, provocative tests using sodium amytal and lidocaine with magnetic stimulation were also performed. The above findings suggest that provocative tests and magnetic stimulation are useful to predict paraplegia, which could result from embolization while, in addition, embolization is considered to be a useful treatment for multiple shunt and nidus in this region.  相似文献   
95.
Device degradation under ac stress in low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs) is analyzed with the density of trap states, electron-emission time, and electron-trapping time as foci. LTPS TFTs are shown to incur greater deterioration of characteristics under ac stress than silicon-on-insulator TFTs. Characteristics are more rapidly worsened as the falling time (t/sub f/) of gate pulses becomes shorter in the range below 1 ms. In addition, the degradation produced by a given number of pulses increases with the duration of the low level of the gate pulse in the range up to 1 ms. These behaviors are due to the slow emission of trapped electrons. On the other hand, the device degradation is independent of the duration of the high level of the gate pulse because the electrons are trapped quickly (in less than 1 /spl mu/s) once the level on the gate becomes high. The U-shaped distribution of trap-state density within the energy gap largely determines the dependence of the ac stress degradation on t/sub f/, since trapped electrons for which the emission time is longer than t/sub f/ are not emitted within the period of transient variation of gate voltage, and the number of electrons emitted after the gate has gone low increases with decreasing t/sub f/. Severe degradation is induced by ac stress conditions that correspond to electron emission from the trap states close to conduction band when the TFT is turned off.  相似文献   
96.
Lipoprotein glomerulopathy (LPG) is a novel disease characterized by proteinuria, lipoprotein thrombi in the glomeruli, and increased concentration of plasma apolipoprotein (apo) E. It is believed that a genetic disorder of apo E may be present and associated with the disease. Three patients with LPG were examined in this study. The patients' DNA sequences were analyzed, and a nucleotide G to C point mutation in exon 4 of the apo E gene was confirmed in each patient. This missense mutation denotes amino acid substitution of the proline residue for arginine residue at position 145 of apo E. This variant (apo E Sendai) may cause a marked molecular conformational change of the apo E. These findings suggest that a novel variant is etiologically related to LPG.  相似文献   
97.
Recently, function-preserving operations have become popular, and pylorus-preserving pancreatoduodenectomy (PPPD) is frequently performed for diseases of the head of the pancreas. However, there are only a few basic studies on the pyloric function after PPPD. Using strain gauge force transducers (SGTs), we studied the pyloric motility of normal and PPPD dogs. We prepared three normal and three PPPD dogs in which the SGTs were implanted onto the antrum and pyloric ring, etc. In conscious dogs, the spontaneous gastrointestinal motility was recorded, and the plasma motilin concentration was measured during the interdigestive state. Following the administration of exogenous Leu13-motilin, the motility was again recorded. The relaxation and opening of the pyloric ring was observed synchronously with intense contractions of the antrum during the phase III of normal dogs. Phase III-like motility was recorded in the PPPD dogs, which was not a typical periodic motility. The plasma motilin concentration of one PPPD dog could be measured, and the motilin levels during the phase III-like motility were higher than during phase I. The phase III-like motility was induced by Leu13-motilin in both normal and PPPD dogs. The phase III-like motility recorded in the PPPD dogs was not a typical periodic one, and this aberrant motility was considered to be one of the causes of delayed gastric emptying. Phase III-like motility was induced by the administration of Leu13-motilin; therefore, it is possible that Leu13-motilin improved the motility of the pyloric ring after PPPD.  相似文献   
98.
Ceruminous glands are modified sweat glands, confined to the skin lining of the cartilaginous part of the external auditory meatus. Tumours arising from these glands are extremely rare. Confusion exists regarding the nomenclature 'ceruminoma' and controversies prevail on the standard way of management. Treatment often involves a multidisciplinary approach, requiring reconstruction after extensive surgical resection. A case report of adenoid cystic carcinoma of ceruminous glands is presented along with discussion of the various pathological types and a review of management.  相似文献   
99.
100.
In this study, we performed immunohistochemical studies using p53 and Ki-67 immunostaining in 48 depressed type adenomas, and compared with protruded type adenomas (n = 28) and depressed type well differentiated mucosal gastric cancers (mcancer: n = 46). Focal and diffuse p53 staining patterns were not noticed in depressed type adenomas and in protruded type adenomas, but were noticed in mcancers (focal: 4.3%, diffuse: 41.3%). Ki-67 positive cells were noticed in surface epithelium in 24.4% of depressed type adenomas, in 21.4% of protruded type adenomas and in 87.0% of mcancers. Ki-67 positive rate in foveolar epithelium (superior, middle, inferior) were noticed in (31.1%, 12.9%, 6.1%) of depressed type adenomas, in (33.4%, 15.4%, 6.9%) of protruded type adenomas and in (33.4%, 31.4%, 20.4%) of mcancers. These results suggest that from the point of immunohistochemistry, depressed type adenomas were similar to protruded type adenomas, but were different from mcancers.  相似文献   
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