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71.
Two red wines with a very high ethanol content were partially dealcoholized by reverse osmosis, so that the influence of this technique on wine color, chemical composition and sensory quality could be studied. No statistically significant differences were found in pH, color intensity, total phenolic index, proanthocyanidin concentration and their mean degree of polymerization between control wines and partially dealcoholized wines (?1 and ?2 vol. %). Some slight but significant differences were found in titratable acidity, anthocyanins, CIELab coordinates and polysaccharides. However, these differences were really quite small and only significant in a few cases. Moreover, a trained panel of tasters had severe difficulty in distinguishing between control and partially dealcoholized wines in triangular tests, and results were statistically significant only in some of the comparisons. It is concluded that this technique can be very useful for the partial dealcoholization of red wines because they hardly alter their composition and sensory characteristics.  相似文献   
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BACKGROUND: Bilateral lung transplantation (BLT) without cardiopulmonary bypass (CPB) may exacerbate reperfusion injury to the initially engrafted lung because of increases in pulmonary flow during implantation of the second graft. METHODS: In a retrospective review of 23 BLT patients, we hypothesized that BLT without CPB injures the first transplanted lung measured by acute and late graft dysfunction compared to the second transplanted lung. Of the 23 BLT, 19 underwent transplantation without CPB while 4 patients were placed on CPB secondary to hemodynamic instability. RESULTS: Acute graft function was assessed by radiographic scoring of lung quadrants (blinded radiologist; 0 = no infiltrate; 1 = infiltrate; maximum = 2 per lung) and by arterial/alveolar oxygen tension ratios (PaO2/ FiO2) ratios. Late graft function was evaluated by quantitative perfusion scan. Lung perfusion was graded as abnormal if less than 50% on the right or less than 45% on the left (Fisher's exact). Radiographic scores were not different between first and second implanted lungs at 1 and 24 hours, PaO2/FiO2 ratios at 1 and 24 hours were 273+/-26 and 312+/-23, respectively, and perfusion scans at 3 and 12 months revealed normal differential blood flow. CONCLUSIONS: These findings suggest no acute or chronic differences occur between the first or second transplanted lung completed without CPB.  相似文献   
74.
Mushroom tyrosinase was immobilized by adsorption onto the totally cinnamoylated derivative of D ‐sorbitol. The polymerization and cross‐linking of the derivative initially obtained was achieved by irradiation in the ultraviolet region, where this prepolymer shows maximum sensitivity. Immobilization of tyrosinase on this support involves a process of physical adsorption and intense hydrophobic interactions between the cinnamoyl groups of the support and related groups of the enzyme. The pH value, enzyme concentration and immobilization time were all important parameters affecting immobilization efficiency; also, enzyme immobilization efficiency correlated well with the tyrosinase isoelectric point. The immobilized enzyme showed an optimum measuring pH of 3.5 and greater activity at acid and neutral pH values than the soluble enzyme. The optimal reaction temperature was 35 °C and the temperature profile was broader than that of the free enzyme or of the enzyme immobilized on other supports. The apparent Michaelis constant of mushroom tyrosinase immobilized on the SOTCN derivative acting on 4‐tert‐butylcatechol (TBC) was 0.40 ± 0.02 mmol dm?3, which was lower than for the soluble enzyme, suggesting that the affinity of this enzyme for this substrate was greater when immobilized than when in solution. Immobilization stabilized the enzyme and made it less susceptible to activity loss during storage at pH values in the range 4–5.5, and the suicide inactivation of the immobilized tyrosinase was null or negligible in a reaction medium with 4‐tert‐butylcatechol at a concentration of 0.4 mmol dm?3. The results show that cinnamic carbohydrate esters of D ‐sorbitol are an appropriate support for tyrosinase immobilization and could be of use for several tyrosinase applications. Copyright © 2005 Society of Chemical Industry  相似文献   
75.
BACKGROUND/AIMS: A prospective study was performed to evaluate the incidence of bile leak after T-tube removal, using 99mTc labelled BULIDA scintigraphy. PATIENTS AND METHODS: Thirty seven patients with choledocholithiasis underwent choledocholithotomy and T-tube drainage. T-tubes were removed on 9--26 postoperative day (mean 13.4 days). RESULTS: Six (16%) patients had scintigraphic evidence of bile leak; 4 patients had leak demonstrated in the early phase only. One patient each had partial persistent leak and complete bile leak. All patients were managed nonsurgically; conservative treatment: (4), percutaneous drainage (PCD) of intra-abdominal collection (1) and endoscopic sphincterotomy and PCD of intra-abdominal collection (1). There was no significant difference in the leak rate when T-tubes were removed at < 2 weeks versus later than 2 weeks (P=.97). CONCLUSIONS: T-tubes should be removed with extreme caution and treatment of symptomatic patients should be guided by clinical and scintigraphic findings.  相似文献   
76.
Thin layer chromatography (TLC) was used to monitor binding of radiolabeled antibodies to cells. Labeled antibodies were reacted with cells and aliquots chromatographed on serum-blocked, ITLC strips. The cell-antibody complexes remain at the origin and unbound antibody migrates with the solvent front. The antibody binding was estimated from the ratio of radioactivity at the origin compared to the total applied. Separations are completed in about 10 min. This method does not use centrifugation or wash steps, and provides an inexpensive and self-contained system to evaluate radioligand binding. Cell binding assay results using this method are approximately the same as those obtained using bead- or cell-type assays.  相似文献   
77.
PURPOSE: The most frequent complication of surgical hemorrhoidectomy is urinary retention. This study evaluates the incidence of urinary retention in a series of patients undergoing surgical hemorrhoidectomy in an ambulatory setting. METHODS: The records of all patients undergoing anorectal surgical operative procedures during the calendar year 1990 were reviewed, with particular emphasis on urinary retention and other postoperative complications. RESULTS: Of 201 patients undergoing full surgical hemorrhoidectomy by Colon and Rectal Clinic, 91 percent had operations performed on an ambulatory basis (discharge less than four hours following surgery). Of these 190 patients, only 1 (0.53 percent) required urinary catheterization during the postoperative period. CONCLUSIONS: The ambulatory setting, when combined with careful patient education and perioperative fluid restriction, allows surgical hemorrhoidectomy to be performed with a very low incidence of urinary retention to the benefit of both patient and surgeon.  相似文献   
78.
Unsaponifiable matter from 19 olive and olive pomace oils were studied by high-resolution13C nuclear magnetic resonance spectroscopy. Their spectra showed characteristic peaks that corresponded to molecular substructures rather than the individual constituents present in the unsaponifiable matter. The presence of squalene and other hydrocarbons, sterols and triterpenic alcohols, in addition to other groups of minor compounds, were observed. Based on the analysis of these spectra, it was possible to distinguish among different grades of olive oils by using stepwise discriminant analysis. This direct method of analysis is suggested to be used in artificial neural networks to define oil identity and quality.  相似文献   
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80.
Because the range of mobile robot sensors is limited and navigation maps are not always accurate, autonomous navigation in dynamic and unknown environments is a big challenge. In this article, we propose two novel autonomous navigation algorithms, which are based on the analysis of three conditions for unobserved and uncertain environments during navigation.

The algorithm for a dynamic environment uses the “known space” and “free space” conditions. It corrects false obstacles in the map when the conventional path is stuck. The navigation algorithm for unknown environments uses the “unknown space” and “free space” conditions. We use the Monte Carlo method to evaluate the performance of our algorithms and the other methods. Experimental results show that our autonomous navigation algorithms are better than the others.  相似文献   

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