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Effective long-term management of urolithiasis depends on identification and manipulation of factors contributing to initial stone formation; identification of these factors depends on accurate identification of the mineral composition of the urolith involved. The purpose of this study was to determine the chemical composition of uroliths obtained from the low urinary tract of dogs in Mexico City. One hundred and five cases of urolithiasis were studied in which stones were surgically obtained from the low urinary tracts of dogs treated in different hospitals. The chemical composition of the uroliths was quantitatively and qualitatively determined by stereoscopic microscopy, IR-spectroscopy, scanning electron microscopy and X-ray microanalysis. Age of animals ranged from 4 months to 14 years, with a median of 5 years. Composition and distribution of the uroliths were struvite 38.1%, calcium oxalate 26.7%, silica 13.3%, urate 7.6%, mixed 11.4%, compounds 1.9%, and cystine 1%. Most uroliths were found in pure breed dogs (75.2%); 23 different breeds were identified, and more than half of the submissions were from breeds of small size. In our study, the frequency of struvite, calcium oxalate, cystine, urates, mixed and compounds stones are in agreement with papers that report on dog populations in America and Europe, but a higher frequency of silica uroliths was observed in Mexico City dogs.  相似文献   
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Hemodialysis induces production of the hepatocyte growth factor (HGF) and decrease of serum hepatitis C virus (HCV) RNA in patients with HCV infection, but it is not known if the hemodialysis schedule or type of membrane affect both the HGF production and HCV viremia. The effects on both parameters of alternate‐day intermittent hemodialysis and short‐daily hemodialysis and high and low flux membranes were investigated in 41 patients treated by hemodialysis. Sixteen (39%) patients were anti‐HCV positive and 11 (69%) had HCV RNA. Twenty‐six patients were on alternate‐day intermittent and 15 on short‐daily hemodialysis. High flux membranes were used for 29 patients and low flux membranes for 12 patients. A decrease in HCV RNA was observed at the end of hemodialysis (8.6 × 105 ± 1.1 × 106 IU/ml vs. 4.4 × 105 ± 7.3 × 105 IU/ml, P = 0.003). The proportion of HCV RNA decrease was similar in patients dialyzed with both schedules and with both types of membranes. The HGF levels increased from 2,605.9 ± 1,428.7 to >8,000 pg/ml at 15 min. At the end of the session, the HGF levels decreased to 5,106.7 ± 2,533.9 pg/ml. The HGF levels at the start of the next session were similar to those at baseline (2,680.0 ± 1,209.3 pg/ml). The increase and dynamics of the HGF levels were similar in patient's hemodialyzed with both schedules and with both types of membranes. These results suggest that changes in HCV RNA and HGF levels during hemodialysis are not influenced by the schedule or type of membrane used. J. Med. Virol. 82: 763–767, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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ABSTRACT: BACKGROUND: The application of new technologies to the education of health professionals is both a challenge and a necessity. Virtual worlds are increasingly being explored as a support for education. Aim: The aim of this work is to study the suitability of Second Life (SL) as an educational tool for primary healthcare professionals. METHODS: Design: Qualitative study of accredited clinical sessions in SL included in a continuing professional development (CPD) programme for primary healthcare professionals. Location: Zaragoza I Zone Family and Community Medicine Education Unit (EU) and 9 health centres operated by the Aragonese Health Service, Aragon, Spain. METHOD: The EU held two training workshops in SL for 16 healthcare professionals from 9 health centres by means of two workshops, and requested them to facilitate clinical sessions in SL. Attendance was open to all personnel from the EU and the 9 health centres. After a trail period of clinical sessions held at 5 health centres between May and November 2010, the CPD-accredited clinical sessions were held at 9 health centres between February and April 2011. Participants: 76 healthcare professionals attended the CPD-accredited clinical sessions in SL. Main measurements: Questionnaire on completion of the clinical sessions. RESULTS: Response rate: 42-100%. Questionnaire completed by each health centre on completion of the CPD-accredited clinical sessions: Access to SL: 2 centres were unable to gain access. Sound problems: 0% (0/9). Image problems: 0% (0/9). Voice/text chat: used in 100% (10/9); 0 incidents. Questionnaire completed by participants in the CPD-accredited clinical sessions: Preference for SL as a tool: 100% (76/76). Strengths of this method: 74% (56/76) considered it eliminated the need to travel; 68% (52/76) believed it made more effective use of educational resources; and 47% (36/76) considered it improved accessibility. Weaknesses: 91% (69/76) experienced technical problems, while; 9% (7/76) thought it was impersonal and with little interaction. 65.79% (50/76) believed it was better than other distance learning methods and 38.16% (29/76) believed it was better than face-to-face learning. CONCLUSIONS: SL is a tool that allows educational activities to be designed that involve a number of health centres in different geographical locations, consequently eliminating the need to travel and making more effective use of educational resources.  相似文献   
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The receptor activity-modifying protein (RAMP)/calcitonin receptor-like (CRL) receptor heterodimer is thought to function as a receptor for either a calcitonin gene-related peptide (CGRP) (CRL receptor/RAMP1) or adrenomedullin (CRL receptor/RAMP2 or -3), depending on the RAMP isoform present. We examined the receptor specificity of adrenomedullin-induced increases in cAMP in human embryonic kidney (HEK)293 cells coexpressing human CRL receptor and human RAMP1 or RAMP2. In cells expressing CRL receptor/RAMP1, adrenomedulin-induced increases in cAMP were comparable to those induced by alpha-CGRP, and the CGRP receptor antagonist alpha-CGRP-(8-37), but not the adrenomedullin receptor antagonist adrenomedullin-(22-52), blocked the adrenomedullin-evoked responses. Cells expressing CRL receptor/RAMP2 responded more selectively to adrenomedullin; in this case, the effect was blocked by adrenomedullin-(22-52) but not by alpha-CGRP-(8-37). Real-time quantitative polymerase chain reaction confirmed that cotransfection of CRL receptor and RAMP1 had no effect on the endogenous expression of RAMP2. Thus, CRL receptor/RAMP1 likely functions as an adrenomedullin receptor as well as a CGRP receptor, which may explain why many of the actions of adrenomedullin are potently antagonized by alpha-CGRP-(8-37).  相似文献   
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Mycosis fungoides (MF) is the most frequent type of cutaneous T-cell lymphoma, whose diagnosis and study is hampered by its morphologic similarity to inflammatory dermatoses (ID) and the low proportion of tumoral cells, which often account for only 5% to 10% of the total tissue cells. cDNA microarray studies using the CNIO OncoChip of 29 MF and 11 ID cases revealed a signature of 27 genes implicated in the tumorigenesis of MF, including tumor necrosis factor receptor (TNFR)-dependent apoptosis regulators, STAT4, CD40L, and other oncogenes and apoptosis inhibitors. Subsequently a 6-gene prediction model was constructed that is capable of distinguishing MF and ID cases with unprecedented accuracy. This model correctly predicted the class of 97% of cases in a blind test validation using 24 MF patients with low clinical stages. Unsupervised hierarchic clustering has revealed 2 major subclasses of MF, one of which tends to include more aggressive-type MF cases including tumoral MF forms. Furthermore, signatures associated with abnormal immunophenotype (11 genes) and tumor stage disease (5 genes) were identified.  相似文献   
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