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991.
GB virus C (GBV-C) RNA was detected in five of 18 patients with aplastic anaemia who had received blood transfusions, whereas it was not detected in eight patients who had not received any transfusions. Antibody against hepatitis C virus (anti-HCV) was detected in nine patients in the transfusion group, compared with one of eight who had not received any transfusions. Therefore, the route of transmission of both GBV-C and HCV in these patients appeared to have been multiple blood transfusion. Since all of the GBV-C RNA-positive patients harboured anti-HCV, GBV-C seems to frequently superinfect with HCV. Neither GBV-C nor HCV is likely to have been a causative agent of the anaemia in the cases examined.  相似文献   
992.
This report describes a case in which a 68-year-old male underwent two operations simultaneously for left coronary ostial stenosis and gastric cancer. Successfully performed procedures were a single coronary artery grafting with the saphenous vein to the left anterior descending artery, and a subtotal gastrectomy using the Billroth II method. The postoperative course was uneventful and the patient was discharged from the hospital in good condition after 42 days. At present, one-year postoperative, the patient has been visiting the outpatient clinic in healthy condition.  相似文献   
993.
Vitellogenin of matrotrophic viviparous eelpout (Zoarces elongatus) was purified from estradiol-17 beta (E2) treated immature male sera by gel chromatography and anion exchange chromatography. Isolated vitellogenin has a molecular weight of 540 kDa estimated by gel chromatography. Serum levels of vitellogenin in females were measured during oocyte development and gestation by single radial immunodiffusion. Serum vitellogenin level was low (less than 0.2 mg/ml) during the early vitellogenic period, increased in the late vitellogenic period to a peak level (6.4 +/- 2.1 mg/ml) at the beginning of gestation. After that it rapidly decreased to a low level (0.1 +/- 0.1 mg/ml) during the early gestation period. Levels of vitellogenin remained low throughout the gestation period. Serum E2 levels in females showed increased from 1.3 to 3.0 ng/ml during the late vitellogenic period, and declined to 0.4 ng/ml during the early gestation period. Serum levels of E2 showed good correlation with serum vitellogenin levels, suggesting that the vitellogenin synthesis is controlled by E2 in this species. These results combined with the matrotrophic growth of embryo during gestation suggest that there is a shift in the synthesis of maternal nutritional products for embryos from the yolk to other nutrients.  相似文献   
994.
PURPOSE: There are different techniques of boost irradiation in the treatment of patients with anal carcinoma. A new system of applicators is presented, which can be used for an intracavitary afterloading therapy. MATERIAL AND METHODS: Three different applicators are available, the first with a central catheter (K1), a second with 5 semicircular fixed catheters (K2) and an eccentric shield, a third with 8 circular fixed catheters and a central shield (K3). RESULTS: The adequate choice of applicator and catheters takes into consideration the individual localisation and extension of anal carcinoma in planning therapy. Thus, in circular growing tumors, an irradiation of the whole circumference of the anal canal is possible. In non-circular growing tumors, the dose applied in the non-affected part of the anal canal can be reduced to a quarter of the dose applied at the tumor. CONCLUSION: The new system of intracavitary afterloading therapy is a good alternative to previous techniques of boost irradiation in the treatment of anal carcinoma. By means of this technique, irradiation can be highly individualized, the tumor better included and non-affected sections of the anal canal saved.  相似文献   
995.
The effect of storage temperature on rheological behaviour of four varieties of baby foods was studied. After 24-month storage at 15C and 25C, the constant A in Weltman model increased significantly for the vegetables, meat and fish samples, and decreased significantly for the fruit samples. After 24-month storage at 5C and 15C there were no significant changes in flow behavior index, consistency index and yield stress of the Herschel-Bulkley model for the vegetables, meat, fish and fruit samples. Increase in storage temperature decreased the consistency index and yield stress of the fruit samples.  相似文献   
996.
Nuclear magnetic resonance imaging (MRI), calorimetry, and temperature measurements were used to monitor cylindrical potato sections frozen at -11C and -42C. MRI showed the advance of the nonsymmetric freezing zone and loss of signal intensity as liquid water turned to ice. Differential calorimetry was used to follow heat removal during transient freezing. Measured times to 95% enthalpy change were 24 min (-42C) and 49 min (-11C), as compared to modeled values of 29 min (-42C) and 100 min (-11C). Times to 95% change in the NMR signal, integrated over the area of the image, were 21 min (-42C) and 56 min (-11C). Changes in NMR signal intensity could be correlated with the amount of unfrozen water remaining after a steady-state had been reached. At -42C, NMR indicated 25% unfrozen water remaining as compared to 26% by calorimetry, and 22% by modeling. At -11C, NMR measured 67% unfrozen water remaining as compared to 48% by calorimetry, and 25% by equilibrium modeling.  相似文献   
997.
Resistance of 19 mold and 6 yeast species to 15 commercial disinfectants was investigated by using a suspension method in which the fungicidal effect and germination time were determined at 20 degrees C. Disinfectants containing 0.5% dodecyldiethylentriaminacetic acid, 10 g of chloramine-T per 1, 2.0% formaldehyde, 0.1% potassium hydroxide, 3.0% hydrogen peroxide, or 0.3% peracetic acid were ineffective as fungicides. The fungicidal effect of quaternary ammonium compounds and chlorine compounds showed great variability between species and among the six isolates of Penicillium roqueforti var. roqueforti tested. The isolates of P roqueforti var. carneum, P. discolor, Aspergillus versicolor, and Eurotium repens examined were resistant to different quaternary ammonium compounds. Conidia and vegetative cells were killed by alcohols, whereas ascospores were resistant. Resistance of ascospores to 70% ethanol increased with age. Both P. roqueforti var. roqueforti and E. repens showed great variability of resistance within isolates of each species.  相似文献   
998.
Hinokitiol, a constituent of the wood of Chamaecyparis taiwanensis, was found to induce differentiation of teratocarcinoma F9 cells. When examined by the agar-overlay method, in which expression of plasminogen activator as a differentiation marker protein was detected, this compound exhibited a dose- and time-dependent induction. Induction of differentiation by hinokitiol occurred irreversibly and required its addition for more than 12h. Among its structure-related compounds tested, tropolone and two colchicine-related compounds exerted potent activities comparable to that of hinokitiol. These findings indicate that free tropolone structure in the molecules plays an essential role in inducing differentiation of F9 cells. Hinokitiol showed a strong inhibitory effect of DNA synthesis in very early stages of culture, suggesting that this effect may be responsible for triggering differentiation of F9 cells.  相似文献   
999.
The present study proposes a detection technique for delaminations in a laminated beam. The proposed technique optimizes the spatial distribution of harmonic excitation so as to magnify the difference in response between the delaminated and intact beam. The technique is evaluated by numerical simulation of two-layered aluminum beams. Effects of measurement and geometric noise are included in the analysis. A finite element model for a delaminated composite, based on a layer-wise laminated plate theory is used in conjunction with a step function to simulate delaminations  相似文献   
1000.
In this article, two new smooth robust nonlinear compensators have been developed, respectively, for positional regulation and trajectory tracking of rigid robot manipulators with internal joint stick-slip friction. The proposed controllers can improve not only the positioning accuracy but also the smoothness of motion. No exact knowledge of the friction models is required for the design of the controllers. Furthermore, the tracking controller is also robust with respect to the uncertain link parameters. Using Lyapunov's direct method, we can show that the time-invariant positional regulation controller guarantees the global boundedness stability of the closed-loop system, while the time-varying positional tracking controller guarantees the global asymptotic stability of the closed-loop system. The numerical simulations of the controllers on a two-link robot are presented as illustrations. © 1994 John Wiley & Sons, Inc.  相似文献   
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