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71.
We operated on a 34-year-old man with a metastatic tumor that extended from the tricuspid valve to the pulmonary valve and obstructed the right ventricle inflow and outflow tracts. The tumor was removed with preservation of the tricuspid valve. Additional chemotherapy was carried out according to the BEPO (etoposid, eisplatin, bleomycin, vincritin) scheme. Histology revealed metastasis of a choriocarcinoma originating from the right testis. Computed tomography performed after 6 months detected no metastases in the lungs. Magnetic resonance imaging showed a thickened right ventricle free wall and apex. The patient is doing well 18 months postoperatively.  相似文献   
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Micrometastases in the sentinel lymph node (SLN) carry a considerable risk of macrometastases in the non-sentinel lymph nodes (NSLN), resulting in axillary lymph node dissection (ALND). Preoperative ultrasound (US) examination of the axillary lymph nodes combined with a fine-needle aspiration biopsy (FNAB) has been proved to discover metastases in the axillary lymph nodes. The aim of our study was to assess the risk of macrometastases in NSLN in patients with micrometastatic SLN after a preoperative US examination of the axillary lymph nodes. The study included 36 patients in whom, after preoperative axillary US, micrometastases in the SLN were revealed and ALND was subsequently performed. At final histopathology, no macrometastases were discovered in the NSLN. In four patients, additional micrometastases were discovered in the NSLN. In conclusion, the risk of macrometastases in the NSLN in patients with preoperatively ultrasonically uninvolved axillary lymph nodes is minimal.  相似文献   
74.
BACKGROUND: Increasing evidence points to the role of the extracellular Calcium Sensing Receptor (CaSR) as a multimodal receptor responding to diverse physiologic stimuli, such as extracellular divalent and polyvalent cations, amino acids, and ionic strength. Within the kidney, these stimuli converge on the CaSR to coordinate systemic calcium and water homeostasis. In this process, the impact of urinary pH changes on the activity of the CaSR has not yet been defined. We therefore performed the present study to analyze the pH sensitivity of the CaSR. METHODS: To assess the activation state of the CaSR, we developed a new method based on the functional coupling between CaSR activity and gating of calcium sensitive potassium currents mediated by SK4 potassium channels. Two-electrode voltage clamping was used to determine whole cell currents in Xenopus oocytes heterologously expressing rat CaSR and rat SK4 potassium channels. RESULTS: Coexpression of CaSR and SK4 gave rise to potassium currents that were dependent on CaSR-mediated intracellular calcium release, and thereby corresponded to the activation state of the CaSR. In presence of extracellular calcium, ambient alkalinization above pH 7.5 increased CaSR activity. Evaluation of the CaSR calcium sensitivity at various ambient proton concentrations revealed that this effect was due to a sensitization of the CaSR towards extracellular calcium. CONCLUSION: Coexpression with SK4 potassium channels provides a fast and sensitive approach to evaluate CaSR activity in Xenopus oocytes. As disclosed by this novel technique, CaSR activity is regulated by extracellular pH.  相似文献   
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We designed a 24-field array and an on-line control box that selects which and how many of 24 fields will conduct electrical charge during functional electrical stimulation. The array was made using a conductive microfiber textile, silver two-component adhesive, and the conductive ink imprint on the polycarbonate. The control box comprised 24 switches that corresponded one-to-one to the fields on the array. Each field could be made conductive or nonconductive by simple pressing of the corresponding push-button type switch on the control box. We present here representative results of the selectivity of the new electrode measured in three tetraplegic patients during functional electrical stimulation of the forearm. The task was to generate finger flexion and extension with minimal interference of the wrist movement during lateral and palmar grasps. Therapists determined the appropriate pattern that lead to effective grasping, lasting on average 5 min per stimulation channel in the first session. This optimal conductive pattern (size and shape) provided effective finger flexion and extension with minimal wrist flexion/extension and ulnar/radial deviations (<10 degrees). The optimal size and shape of the electrode in all cases had a branched pattern. The selection of the optimal stimulation site was achieved without moving the electrode. The size and shape were reproducible in the same subject from session to session, yet were different from subject to subject. The optimal electrode size and shape changed when subjects pronated and supinated their forearm. The control box includes a program that can dynamically change the number and sites of the conductive fields; hence, it is feasible to use this during functional movements. Subjects learned how to determine the optimal electrode pattern; hence, these electrodes could be effective for home usage.  相似文献   
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About 25% of all liver transplantations in USA are performed for liver disease due to viral hepatitis, 25% of them related to hepatitis B. It is also known that 90%-100% of transplanted persons with proven replicative stage of hepatitis B [HBeAg (+), HBV DNA (+)] develop reinfection of the transplanted liver in the absence of prophylaxis. This percentage is lower (30%-50%) in patients with nonreplicative stage of infection [HBeAg (-), HBV DNA (-)]. The consequence of most transplant infections is death due to the transplanted organ failure. The prophylaxis of infection is possible, however a combination of intravenous hepatitis B hyperimmune gammaglobulin and lamivudin may be too expensive for some transplantation centers in less developed countries. The aim of this article is to recommend prophylaxis and treatment of recurrent hepatitis B in persons with transplanted liver using data of the Consensus Conference on Hepatitis B in Geneva 2002, Canadian Consensus Group for Hepatitis (CASL) and EASL International Consensus Conference on Hepatitis B that should be available for patients in Croatia.  相似文献   
79.
There has been a dramatic improvement in diagnostic procedures and therapy of viral hepatitis in the last 20 years. Improvements in therapy caused an increase in actual cost, however, with significant long-term savings through a decreased cost of treatment of advanced liver disease including liver transplantation. The Croatian National Board for Viral Hepatitis has decided to initiate the organization of consensus conference on viral hepatitis enabling the leading experts in the country to give the best possible recommendations for the diagnosis, prophylaxis and therapy in our circumstances. The Consensus Conference took place in Zagreb in June 2004, with update in March 2005, organized by the Croatian National Board for Viral Hepatitis, Reference Centers of the Ministry of Health for Chronic Liver Diseases, Infectious Diseases and AIDS, Croatian Society of Gastroenterology--Hepatology Section, Croatian Society for Nephrology, Dialysis and Transplantation, and Croatian Institute for Health Insurance. Invited experts provided written reports on the respective subjects that appear in this issue and their recommendations resulting in this consensus statement.  相似文献   
80.
The purpose of the study was to assess the incidence, type and dynamics of electrocardiography (ECG) alterations in patients with haemorrhagic fever with renal syndrome (HFRS) according to different stages of the disease. 79 patients hospitalized at the University Hospital for Infectious Diseases in Zagreb during the large HFRS outbreak in Croatia in 2002 were retrospectively analysed. HFRS diagnosis was confirmed by enzyme-linked immunosorbent assay. A 12-lead resting ECG was obtained. 30 (38%) patients had abnormal ECG findings, most frequently in the oliguric stage. Increased levels of urea and creatinine were observed in all patients with abnormal ECG, along with abnormal chest X-ray in nearly 50% of cases. Sinus tachycardia was the most frequent ECG disorder in the febrile stage, and bradycardia in the oliguric stage. During the course of disease, some other ECG disorders were recorded: bundle branch conduction defects, non-specific ventricular repolarization disturbances, supraventricular and ventricular extrasystoles, prolonged QT interval, low voltage of the QRS complexes in standard limb leads, atrioventricular block first-degree, and atrial fibrillation. Myocarditis was present in 3 patients. In conclusion, abnormal ECG was found in more than one-third of HFRS patients with the most common findings during the oliguric stage. All ECG changes were transient.  相似文献   
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