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AG González NL Alvarenga AG Ravelo IA Jiménez IL Bazzocchi NJ Canela LM Moujir 《Canadian Metallurgical Quarterly》1996,43(1):129-132
OBJECTIVE: To calculate and compare the costs of the treatment of varicocele by antegrade scrotal sclerotherapy with other modalities. PATIENTS AND METHODS: A total of 2305 operations using antegrade scrotal sclerotherapy to treat varicocele in childhood and adolescence were analysed for cost factors and compared with different surgical treatment methods for varicocele. RESULTS: Calculation of the pre-, intra- and post-operative costs showed that antegrade scrotal sclerotherapy was the most economically effective of all forms of surgical management for varicocele. CONCLUSIONS: Because antegrade scrotal sclerotherapy is a cost-effective treatment for varicocele, the indications for treatment may be widened to include more men with potential infertility, and thus avoid the need for expensive methods of artificial fertilization. 相似文献
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Hip involvement in ankylosing spondylitis (AS) is a common and disabling problem. The clinical and x-ray records of 87 patients with definite AS (Rome criteria) were examined to define and characterize their hip disease. Clinical hip disease was present in 33 cases (38%), was usually bilateral (91%), and tended to begin early in the disease course; it was the cause of 50% of the Class III and IV disability in the entire study group. Typical findings included regional pain, limitation of motion, muscle atrophy, and flexion contractures. Radiologic hip abnormalities occurred in 42 cases (48%). The radiographic pattern was distinctive when compared to that in two control groups and included axial migration of the femoral head (63%), concentric joint space narrowing (50%), rufflike femoral osteophytosis (36%), and protrusio acetabuli (30%). Eight patients required bilateral hip surgery. Para-articular ossification occurred in 8 of 16 replaced hips; in 5 of 8 hips it caused clinical immobility. This potentially serious complication may limit the usefulness of hip arthroplasty in some AS patients. 相似文献
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IL Woolf N El Sheikh H Cullens WM Lee AL Eddleston R Williams AJ Zuckerman 《Canadian Metallurgical Quarterly》1976,2(6037):669-671
The possible importance of humoral immunity in the pathogenesis of fulminant hepatitis was investigated by comparing 17 patients with fulminant hepatitis type B with 20 patients with severe but non-fulminant disease. Hepatitis B surface antigen (HBsAg) was cleared from the serum significantly faster (P less than 0-001) in those with fulminant hepatitis, and in 41% anti-HBsAg (HBsAb) was detectable by radioimmunoassay (RIA) at presentation. In all 11 sera from patients with fulminant hepatitis that were examined by electron microscopy aggregates of HBsAg and HBsAb were seen. In contrast, HBsAb was never detected by RIA in those with non-fulminant hepatitis, and in only one serum specimen (5%) were aggregates seen on electron microscopy. A significant sex difference between fulminant and non-fulminant hepatitis was observed, 65% of patients with fulminant hepatitis but only 15% of patients with non-fulminant hepatitis being women (P less than 0-01). An enhanced production of HBsAb in fulminant hepatitis, by leading to free HBsAb in portal blood, may cause an Arthus reaction in the sinusoids of the liver with ensuing ischaemic necrosis of hepatocytes. 相似文献
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The potential use of ricin as a biological weapon in food highlights the necessity for the development of food-specific detection methods. Current methods for the detection of ricin consist of various immunoassays, which detect only one subunit of the ricin toxin and therefore may not be indicative of a biologically active molecule. An in vivo assay, such as a mouse bioassay, can indicate the biological activity of the toxin; however, this method is not feasible for laboratories that do not have animal testing facilities. The purpose of this study was to develop an in vitro assay for the detection of biologically active ricin in beverages and liquid foods. Acidic and high-protein beverages were spiked with either purified ricin or ground castor beans and added to cultured human Jurkat cells. After an overnight incubation, the supernatant was tested for lactate dehydrogenase (LDH) activity with a colorimetric assay. LDH was released from the cytosol upon cell damage and was positively correlated with cell death. Ricin was detectable in all the matrices tested, with a sensitivity of 10 to 100 pg/ml. Biologically active ricin was detectable in all the matrices incubated with ground castor bean material. This method provides a confirmatory way to detect biologically active ricin that can be utilized by laboratories lacking animal facilities. 相似文献
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M.B. SÁNCHEZ‐ILÁRDUYA C. SÁNCHEZ‐FERNÁNDEZ M. VILORIA‐BERNAL D.M. LÓPEZ‐MÁRQUEZ L.A. BERRUETA B. GALLO F. VICENTE 《Australian Journal of Grape and Wine Research》2012,18(2):203-214
Background and Aims: During wine ageing, a great variety of reactions take place, resulting in an immense variety of products whose structure sometimes remains unknown. The aim of this work is the study of different fragmentation patterns of flavanol‐anthocyanin derivatives formed along the wine ageing; these patterns are useful for elucidating the different structures of these compounds and other new related ones. Methods and Results: Several wines from the Protected Denomination of Origin Rioja have been studied by an analytical method that combines column chromatography and high‐performance liquid chromatography with diode array and mass and tandem mass spectrometric detections. Thirty‐five coloured flavanol‐anthocyanin compounds formed by direct reaction or by acetaldehyde‐mediated condensation have been identified. For direct reaction derivatives, two different fragmentation patterns (one of them not previously reported) have been observed depending on the position of flavanol in the coloured derivative. Several compounds have been identified in aged wines for the first time to the authors' knowledge, like (+)‐gallocatechin‐cyanidin‐3‐glucoside and (+)‐catechin‐cyanidin‐3‐glucoside Conclusions: The developed analytical procedure has allowed the identification of some compounds for the first time, and two different fragmentation patterns have been observed depending on the position of flavanol in the pigment. Significance of the Study: The establishment of different fragmentation patterns allows the structural elucidation of unknown compounds. 相似文献