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AIM OF STUDY: To measure the effect of specific preoperative information on postoperative anxiety, satisfaction with information, and demand for analgesia, of Chinese males having transurethral resection of the prostate (TURP). DESIGN: A controlled experimental design. The researchers allocated all patients (n = 30) undergoing TURP in a general hospital in Hong Kong, during a 3-month period, to one of two groups. The experimental group (n = 15) received a specific information pamphlet and a general preoperative counselling video. The control group (n = 15) received a video alone. PROCEDURE AND MEASURES: Following ethical approval, a researcher took baseline measures of state and trait anxiety using the Chinese State-Trait Anxiety Inventory (C -STAI). Five days after surgery the researcher administered the C-STAI (A-State), a patients' satisfaction questionnaire, and, recorded requests for analgesia during the first 5 postoperative days. RESULTS: Experimental subjects reported significantly lower anxiety levels post-operatively and a significantly higher level of satisfaction with the preoperative information, than controls. Postoperative demand for analgesia did not significantly differ between groups. CONCLUSIONS: The findings support the importance of providing patients with specific, written preoperative information about their surgery and its effects to minimize their postoperative anxiety levels, and improve their satisfaction with the care provided.  相似文献   
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A simple, rapid, and specific high-performance liquid chromatographic (HPLC) procedure is described for the analysis of the chemical sweetener L-aspartyl-L-phenylalanine methyl ester (aspartame). Using a strong cation exchange column and pressures less than 1000 psig, an analysis can be performed in less than 15 min. The technique has been applied to a wide range of food products and formulations. No interferences were found in the samples studied. Recoveries are quantitative, and the coefficients of variation for replicate analyses are less than or equal to 2.5%.  相似文献   
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The clinical and histological features of oncocytic adenomatous hyperplasia, papillary adenoma, and papillary adenocarcinoma of the oral cavity are described, and the literature is reviewed. Histological features which may be of value in distinguishing between benign and malignant variants are described, and in view of the slow growth rate of most of these tumours, the importance of long-term follow-up is stressed.  相似文献   
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In situ scanning tunneling microscopy (STM) of redox molecules, in aqueous solution, shows interesting analogies and differences compared with interfacial electrochemical electron transfer (ET) and ET in homogeneous solution. This is because the redox level represents a deep indentation in the tunnel barrier, with possible temporary electronic population. Particular perspectives are that both the bias voltage and the overvoltage relative to a reference electrode can be controlled, reflected in spectroscopic features when the potential variation brings the redox level to cross the Fermi levels of the substrate and tip. The blue copper protein azurin adsorbs on gold(111) via a surface disulfide group. Well resolved in situ STM images show arrays of molecules on the triangular gold(111) terraces. This points to the feasibility of in situ STM of redox metalloproteins directly in their natural aqueous medium. Each structure also shows a central brighter contrast in the constant current mode, indicative of 2- to 4-fold current enhancement compared with the peripheral parts. This supports the notion of tunneling via the redox level of the copper atom and of in situ STM as a new approach to long-range electron tunneling in metalloproteins.  相似文献   
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Epstein-Barr virus (EBV) is associated with the development of several B cell malignancies including Burkitt's lymphoma (BL), post-transplant lymphoproliferative disease (PTLD), and AIDS-related lymphomas. The latter two diseases result from EBV-driven B cell proliferation in the absence of normal immunosurveillance and as such, represent a heterogenous family of lymphoproliferative disorders. This article reviews studies on EBV gene expression and antibody development in PTLD and introduces recent information on the levels of EBV+ peripheral blood lymphocytes to discuss possible mechanisms of pathogenesis under varying conditions of immunosuppression.  相似文献   
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