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61.
BACKGROUND: Increased abdominal pressure is associated with elevations in the intracranial pressure (ICP) and impaired renal function. These adverse effects are potentially important in clinical situations such as severe abdominal trauma and laparoscopic donor nephrectomy. It was hypothesized that the secondary elevation of ICP leads to release of vasoconstrictors, which may affect renal function by decreasing the renal blood flow (RBF). We investigated the effect of laparoscopy on ICP and renal blood flow in a porcine model. MATERIALS AND METHODS: The abdominal pressure of swine (N = 5; 20-25 kg) was gradually increased from baseline to 5, 15, and 25 mm Hg by insufflation of nitrogen into the abdominal cavity. The ICP was measured using a Camino monitor, and RBF was simultaneously measured using a Transonic Doppler probe placed on the renal artery. Results were analyzed using repeated measures ANOVA and the paired t-test. RESULTS: No significant change from baseline was observed in ICP and RBF when the abdominal pressure was 5 mm Hg. However, both ICP and RBF were affected by increasing the abdominal pressure to 15 and 25 mm Hg (P = 0.035 and 0.04 for ICP and P = 0.074 and 0.034 for RBF, respectively). CONCLUSIONS: Low-pressure laparoscopy may reduce the adverse effects of pneumoperitoneum on ICP and RBF. It may be advisable to use low pressures in laparoscopic surgery, especially when changes in ICP or renal perfusion may have significant clinical implications.  相似文献   
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We report the case of a 32 years old male patient with carotid-cavernous fistula caused by head injury who died from massive epistaxis. Treatment assessment of this case is faced with the literature.  相似文献   
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BACKGROUND: Immune reconstitution after hematopoietic stem-cell transplantation (HSCT) occurs gradually. Thus, a variable period of immunodeficiency may be present, leading to immunomediated complications, such as graft-versus-host disease (GVHD) and opportunistic infections. METHODS: To better understand the kinetics of B-cell repertoire reconstitution in children, 49 pediatric patients were analyzed before and after transplantation by immunoglobulin (Ig) HCDR3 fingerprinting, which is a molecular technique that analyzes one of the hypervariable segments of the Ig heavy chain, which provides the amino acid residues that are essential to interact with antigens. RESULTS: In healthy donors, the CDR3 fingerprinting profile shows 16 to 20 bands, and each band corresponds to a particular length of CDR3. This situation is considered polyclonal. Patients analyzed just after transplantation show strong oligoclonality, because only a few CDR3 bands are detected within the first 3 to 6 months. CONCLUSIONS: The authors' data show a significant lag in diversification of the B-cell repertoire, which reaches the polyclonal situation of normal healthy donors approximately 6 months after HSCT. This period may vary depending on the type of transplant (autologous vs. allogeneic) and on the immunosuppressive therapy related to GVHD.  相似文献   
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BACKGROUND: Preoperative procedures are often necessary to localize pulmonary nodules during thoracoscopic resection in order to reduce the necessity of resorting to thoracotomy. The aim of this report is to describe the strategy we developed to limit preoperative techniques without reducing the thoracoscopic success rate of localization.METHODS: Between January 2000 and December 2003, 183 patients underwent video thoracoscopic resection of small pulmonary nodules. The patients were divided into two groups on the basis of the radiological features of the nodule. The subjects in group 1 were operated on directly, and endothoracic ultrasonography was performed when necessary. The subjects in group 2 underwent preoperative radionuclide labeling of the nodule. RESULTS: In group 1, 112 out of 119 nodules (94%) were localized. Twenty-five out of 32 lesions, neither visible nor palpable, were found by endothoracic ultrasonography. In group 2, we localized 62 out of 64 nodules (97%). CONCLUSIONS: Currently, we cannot completely avoid preoperative labeling techniques for thoracoscopic resection of small pulmonary nodules. However, correct patient selection may limit this necessity, without an increased conversion rate to thoracotomy, if endothoracic ultrasonography is available.  相似文献   
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Since etiology and pathogenesis of most systemic and/or isolated vasculitides are unknown, any attempt to make a rational classification of these entities is far from being perfect. Vasculitis may be a primary disease or it may be associated with connective tissue diseases, infectious diseases, neoplasms, drug assumption, allograft rejection and so on. As secondary vasculitides constitute the majority of cases, diagnosis of primary vasculitis is made by exclusion. At the present time, the 1993 Chapel Hill Consensus Conference on Nomenclature of Primary Vasculitides provides a useful guide to clinician and pathologist for evaluating a patient with an idiopathic form of vasculitis. This classification is based on the predominant size of vessels affected and describes the main clinico-pathologic features of the various clearly defined types of systemic vasculitis. Though it suffers from omissions and contradictions, in routine practice it is of great help to distinguish diseases in this intriguing chapter of pathology.  相似文献   
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