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The purpose of this study was to evaluate whether the plasma brain natriuretic peptide (BNP) concentration is a useful marker of right ventricular (RV) overload and whether it has prognostic value as a predictor of death in patients with chronic respiratory disease (CRD). We measured the plasma BNP and atrial natriuretic peptide (ANP) concentrations in 31 consecutive patients with CRD who underwent right-heart catheterization to evaluate pulmonary hypertension. All patients were followed for >12 months. The plasma BNP concentration closely correlated with the mean pulmonary artery pressure and pulmonary vascular resistance (r=0.62, P<0.0005 and r=0. 85, P<0.0001), and showed a weak linear correlation with cardiac output (r=-0.36, P<0.05). During the follow-up period, 5 (16%) end-stage CRD deaths (4 RV heart failure and 1 respiratory infection) and 2 non-end-stage CRD deaths occurred. In a stepwise multivariate Cox proportional-hazards regression analysis including age, sex, BNP, ANP, hemodynamic variables and the ratio of PaO(2) to fraction of inspired oxygen, only BNP (P<0.05) was an independent predictor of end-stage CRD death. The upward and leftward shift in the receiver operating characteristic curve between patients with end-stage CRD death and those without was greater for BNP than for ANP. Our findings suggest that the plasma BNP concentration may be an inexpensive, simple and useful marker of RV overload and end-stage CRD death in CRD patients. These preliminary results need to be confirmed in a large series of CRD patients.  相似文献   
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The pancreatic endocrine tumors are uncommon neoplasms and are classified into non-functional and functional tumors. According to whether the secreted hormones are originated from pancreatic islet cells or not, the tumors are also classified into normotopic and ectopic tumors. Except for insulinoma, more than 60% of them reveal malignant behavior. The presence of endocrine tumor is diagnosed when patients develop a hormone-specific symptom, and the location of tumors are usually diagnosed by a combination of ultrasonography, computed tomography, magnetic resonance imaging and selective angiography. A somatostatin receptor scintigraphy is promising. Nevertheless, these examinations occasionally failed to precisely locate the tumors especially when they are very small and/or multiple. For such cases, both portal venous sampling and arterial provocation test are helpful.  相似文献   
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Background Laparoscopic and robotic surgeries have become popular, and this popularity is increasing. However, the environment in which such surgeries are performed is rarely discussed. Similar to arthrosurgery performed in water, artificial ascites could be a new environment for laparoscopic surgery. This study was performed to determine whether robotic surgery is applicable to complicated suturing underwater. Material and methods A da Vinci Surgical System S was used. A weighted fabric sheet was placed at the bottom of a tank. Identical sets were made for each environment: One tank was dry, and the other was filled with water. The suturing task involved placement of a running silk suture around the perimeter of a small circle. The task was performed eight times in each environment. The task time and integrity score were determined. The integrity score was calculated by evaluating accuracy, tightness, thread damage, and uniformity; each factor was evaluated using a five-point scale. Results Although statistically significant differences were not shown in either task time or integrity score between the underwater and air environments, robotic suturing underwater is not inferior to performance in air. Conclusions The feasibility of robotic suturing underwater was confirmed under the herein-described experimental conditions.  相似文献   
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Objectives: To investigate intraoperative and early postoperative complications of antegrade radical prostatectomy with intended wide resection (aRP) for clinically locally advanced prostate cancer (cLAD) and to compare with those of aRP for clinically localized prostate cancer (cLD). Methods: Between March 1994 and June 2007, 800 consecutive Japanese patients including 625 with cLD and 175 with cLAD underwent aRP and bilateral limited lymphadenectomy. Clinicopathological data including intraoperative and early postoperative complications (within 30 days after operation) were compared between cLD and cLAD groups. Results: No deaths occurred. Operative time and blood loss did not differ significantly between the groups. Intraoperative and early postoperative complications were observed in 11 (1.4%) and 123 (15.4%) of the entire cohort, respectively. Prevalent early postoperative complications were pelvic hematoma, wound infection, urinary retention and lymphocele or prolonged lymph drainage. There were no significant differences in the entire intraoperative and early postoperative complications between the groups. The majority of the early postoperative complications were minor. Conclusions: aRP for cLAD is technically feasible and a safe surgical procedure. If radical prostatectomy could be established as a standard treatment for cLAD in the future, aRP might be valuable as the first step of multimodal treatments.  相似文献   
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Carcinomatous pleuritis, accompanied by pleural dissemination or malignant pleural effusion, is listed as one of the factors limiting adequate surgical treatment. It is relatively easy to peel the parietal pleura of the chest wall and mediastinum during a pleuropneumonectomy, but it is quite difficult to peel the parietal pleura of the diaphragm. A pleuropneumonectomy was conducted with the combined resection of the pericardium and all layers of the diaphragm without opening of the peritoneum through a posterolateral subcostal approach. This approach thus made it possible to perform a complete resection of the diaphragm relatively easily in a reliable manner, and also contributed to a more thorough resection of pleural dissemination without a second thoracotomy.  相似文献   
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