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81.
Cytosol prepared from Chinese hamster ovary (CHO)-K1 cells transfected with guinea pig estrogen sulfotransferase (EST) cDNA demonstrated high affinity binding activity for pregnenolone as well as 17 beta-estradiol but failed to bind dehydroepiandrosterone or testosterone. In contrast, cytosol prepared from nontransfected CHO-K1 cells did not demonstrate steroid binding activity. Additionally, the binding activity for pregnenolone and 17 beta-estradiol was dependent on the presence of the cofactor adenosine-3',5'-diphosphate. Pregnenolone and 17 beta-estradiol effectively competed with each other for binding. On the other hand, pregnenolone, which was not sulfonated, did not inhibit the sulfonation of 17 beta-estradiol by expressed EST.  相似文献   
82.
Long-term survival of carcinomas in the body and tail of the pancreas after surgery is still rare. One of the major reasons for unresectability is cancerous invasion to major vessels, such as the common hepatic and splenic arteries. Resection of the involved arteries can increase resectability and thus might increase post-operative survival. The aim of this study was to clarify the importance of the Appleby operation for carcinoma of the body and tail of the pancreas. A Case Report was carried out with a 54 year-old man, had suffered back pain and loss of body weight for six months. Imaging procedures such as US, CT or angiography showed a carcinoma in the body of the pancreas, about 3 cm in size, and both the common hepatic and splenic arteries were invaded by the tumor. The Appleby operation was used for this patient, since firstly there was no invasion to the head of the pancreas, secondly neither the proper hepatic artery nor the SMA was involved, thirdly the root of the CA was free of carcinoma, and finally because clear pulsation of the proper hepatic artery could be felt one or two minutes after occlusion of the CHA, which indicated that resection of the CHA would not lead to hepatic ischemia. The postoperative course was uneventful. His appetite recovered well and his body weight increased to the level before the disease. The patient was relieved from back pain and has returned to work 18 months after the operation, although he had a local recurrence eight months after the operation. In addition, eleven cases with carcinoma of the body and tail of the pancreas were used for a literature review. The average survival time after the Appleby operation is 6.6 months, and four patients are still alive. One patient has survived 13 years after the operation. It was concluded that although the prognosis after Appleby procedure is still not satisfactory that this operation can at least offer patients a better quality of life.  相似文献   
83.
Energy absorbability of foamed rigid materials, polyurethane and glass, was studied under a compressive load. The brittle materials were proved to absorb much energy in a manner similar to ductile materials. A mechanism for such high energy absorption was proposed, based on a fracture model in which crushing of cells initiates at the weakest cell followed by propagation to cells lying in the layer containing the weakest one and lying in a direction perpendicular to the compressive force; then the crushing propagates to another layer under the compressive force after the completion of the first layer crushing. In the period of one layer crushing, the strain energy stored in the period of compression prior to the crushing is temporarily released, and it is stored again in the period of compression after the crushing. The store and release of strain energy is assumed to be repeated until all cell layers are crushed. This mechanism of layer-by-layer crushing allows the cells to absorb strain energy repeatedly, and causes high energy absorption in the brittle foamed material. The calculated energy based on the mechanism agrees well with the observed one.  相似文献   
84.
Forty-two patients with gastric cancer were entered in this study. Forty-one of them were eligible and administered sequential methotrexate (MTX)/5-fluorouracil (5-FU) with 5'-deoxy-5-fluorouridine (5'-DFUR). 5-FU was administered intravenously by drip infusion for 2 hours in 22 cases (group A), and was infused by bolus injection in 19 cases (group B). The treatment schedules were as follows: MTX 100 mg/m2 was given intravenously (i.v.) followed by 5-FU 600 mg/m2 i.v. 2 hours later and leucovorin 15 mg/body i.v. 8 and 20 hours later. This cycle was repeated once a week. 5'-DFUR 1,200 mg/body/day was given orally on 5 consecutive days per week. Three of 20 cases (15%) in group A showed PR, while 5 of 15 cases (33%) in group B showed PR. Median survival time was 2.8 months in group A and 3.7 months in group B. There was, however, no statistical difference. Gastrointestinal toxicity was commonly observed. Leukocytopenia was more severe in group B. Alopecia was more frequently observed in group B (p < 0.025). These results suggested bolus injection of 5-FU was a promising way of administration in sequential MTX/5-FU therapy.  相似文献   
85.
We analyze the dependence of the reconstructed image characteristic on the observation condition in the light-in-flight recording by holography both theoretically and experimentally. This holography makes it possible to record a propagating light pulse. We have found that the shape of the reconstructed image is changed when the observation position is vertically moved along the hologram plane. The reconstructed image is numerically simulated on the basis of the theory and is experimentally obtained by using a 373 fs pulsed laser. The numerical results agree with the experimental result, and the validity of the theory is verified. Also, experimental results are analyzed and the restoration of the reconstructed image is discussed.  相似文献   
86.
87.
BACKGROUND: There are a few patients without detectable atrial contraction despite restoration of atrial rhythm after the maze procedure for atrial fibrillation (AF) associated with mitral valve disease. METHODS: From January 1995 to March 1997, 29 consecutive patients with AF associated with mitral valve disease underwent our modified maze procedure combined with mitral or other valve operations. The causes of mitral valve disease were rheumatic mitral stenosis (n = 22) and nonrheumatic mitral regurgitation (n = 7). The 17 patients with postoperative atrial rhythm were divided into group I with rheumatic mitral stenosis (n = 10), and group II with mitral regurgitation of nonrheumatic origins (n = 7). RESULTS: Seventeen patients regained atrial rhythm, 2 patients had junctional rhythm, and another 10 remained in AF. Between the group of patients with restoration of atrial rhythm and that of patients remaining in AF, significant differences were found in the percentage with rheumatic disease, history of AF, and maximum f-wave voltage. The postoperative peak velocity of the atrial filling wave to peak velocity of early filling wave ratio for the left atrium measured using Doppler echocardiography was 0.25 in group I, which was significantly lower than that (0.42) in group II. CONCLUSIONS: Reconsideration of the indications for the maze procedure for AF associated with rheumatic mitral stenosis may thus be reasonable, particularly for cases in which replacement using a prosthetic valve is necessary, but we believe that patients with nonrheumatic mitral valve disease, especially those able to undergo reconstructive operations, are the best candidates for the maze procedure.  相似文献   
88.
The natural frequencies and response of a circular cylindrical liquid bridge consisting of incompressible and non-viscous liquid has been determined. Three cases of pitching excitations have been treated: synchronous- and counter-excitation of the end discs, as well as the pitching excitation of only one end disc. The contact lines were considered to be anchored at the end discs.  相似文献   
89.
This paper reviews the synthesis and characterization of several transparent glass-ceramics with optical active nanocrystals. Glass-ceramics containing ferroelectric SrxBa1-xNb2O6 nanocrystals with an ellipsoidal shape show optical phase modulations in the presence of alternative electric fields. In the glass-ceramics with Ba2TiSi2O8 (BTS) nanocrystals, BTS crystalline layers with a thickness of approximately 120 nm are formed at the surface and ellipsoidal-shaped crystallites with a diameter of 100–200 nm are dispersed in the glass matrix. Some TeO2-based and GeO2-based glasses show a prominent nanocrystallization. RE-doped CaF2 nanocrystals are patterned in a spatially selected region by laser irradiations. The size, morphology, and dispersion state of nanocrystals should be carefully checked in each glass system and composition. The basic concept for the design of glass system and composition is also discussed. Some data on optical active performances in transparent glass-ceramics with nanocrystals were introduced.  相似文献   
90.
In spent fuel pools at the Fukushima Daiichi Nuclear Power Station (1F), seawater was injected for cooling purposes after the tsunami disaster in March 2011. It is well known that the chloride in the seawater has the potential to cause localized corrosion (e.g., pitting corrosion) in metals. In this study, we evaluated the pitting potentials of zircaloy-2, the material used in the fuel cladding tubes in 1F, as a function of chloride concentration. To accomplish this, we used artificial seawater under gamma-ray irradiation and investigated the effect of radiolysis on pit initiation of zircaloy-2 in water containing sea salt. Changes in the composition of water containing sea salt were analyzed as well, both before and after gamma-ray irradiation. The characteristics of the resultant oxide films formed on zircaloy-2 were evaluated by X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy. The experimental results showed that the pitting potential under irradiation was slightly higher than that under conditions in which no radiation was present, and that the pitting potential decreased with increasing chloride concentration in the presence as well as the absence of radiation. Solution analyses for water containing sea salt showed that hydrogen peroxide was generated by irradiation. The oxide film was composed of zirconium oxide and was made thicker during the irradiation. The higher pitting potential could thus be explained by the capacity of hydrogen peroxide to oxidize the surface and enhance oxide film formation. Under gamma-ray irradiation, the zircaloy-2 surface with an oxide film formed by radiolysis products was found to be resistant to pitting in the presence of chloride.  相似文献   
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