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41.
The effectiveness of transpedicular calcium phosphate cement (CPC) injection as a new treatment for osteoporotic compression fracture of vertebrae was evaluated by measuring the compressive strength and the mode of failure in vertebrae experimentally injected with CPC. Forty-five human cadaver vertebrae were divided into three groups: a control group; group A, in which CPC was injected into the upper half of the vertebral body; and group B, in which CPC was injected into the whole vertebra. The load-displacement curve characteristically had two peaks in group A, and decreased rapidly after failure in group B. The failure site was the cancellous bone immediately below the cranial endplate in the control group, cancellous bone immediately below the CPC injection area in group A, and in the CPC injection area in group B. Although mechanical strength was greatest in those vertebrae in which the entire cancellous bone was replaced with CPC, the compressive strength of the vertebrae was also increased by partial replacement of cancellous bone with CPC injection. In terms of mode of failure and mechanical gradient with adjacent vertebrae, there were several advantages for those vertebrae in which the cranial half of the cancellous bone was replaced with CPC. Received: May 29, 2000 / Accepted: September 20, 2000  相似文献   
42.
BACKGROUND: FR167653 is a potent suppressant of tumor necrosis factor (TNF)-alpha and interleukin-1 (IL-1) production, and was shown to attenuate ischemia and reperfusion (I/R) organ injury in our previous experiment. Because p38 mitogen-activated protein (MAP) kinase has been reported to regulate the production of TNF-alpha and IL-1, we examined the effects of FR167653 in the rat lung I/R model and determined the expression and activation of p38 MAP kinase. METHODS: Experiment 1: After 1 hour of ischemia, p38 MAP kinase, phosphorylated p38 MAP kinase (active form), histologic changes of the lung, and serum levels of TNF-alpha and IL-1beta were examined. Experiment 2: After 2 hours of reperfusion, arterial oxygen content (PaO(2)) and saturation (SaO(2)), serum TNF-alpha and IL-1beta levels, and histologic changes in the lung were examined. Rats were divided into three groups in Experiment 1. In the control group, a saline solution was administered and, in the FR group, 0.1 mg/kg per hour of FR167653 was administered, intravenously throughout the experiment, beginning 30 minutes before ischemia. In the non-ischemic group, samples were taken soon after thoracotomy. The rats were divided into control and FR groups in Experiment 2. RESULTS: Experiment 1: One hour of ischemia induced almost no changes in the lung or serum cytokine levels. Meanwhile, FR167653 markedly attenuated the expression of phosphorylated p38 MAP kinase. Experiment 2: SaO(2) and PaO(2) were improved, serum cytokines were lower, and lung damage was less extensive in the FR group than in the control group. CONCLUSION: FR167653 attenuates I/R injury of the lung and this attenuation is associated with suppression of p38 MAP kinase activation.  相似文献   
43.

Backround  

Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis.  相似文献   
44.
Background/Purpose Endoscopic drainage of pancreatic pseudocysts using transpapillary and transmural approaches has been reported. In this study, endoscopic nasopancreatic drainage (ENPD) and pancreatic stenting were performed in patients with pseudocyst and abscess associated with acute pancreatitis, and the usefulness and problems of the procedures were investigated. Methods After endoscopic retrograde pancreatography was done, ENPD and/or pancreatic stenting were performed in 13 patients with pancreatitis and pseudocyst or abscess that communicated with the main pancreatic duct. Results ENPD was performed in seven patients, and was effective in all five patients with cysts: the cysts disappeared or shrank. However, the condition in the two patients with abscess was unchanged, and percutaneous drainage was performed. Stenting was carried out in six patients, and the cyst disappeared or pancreatitis was improved in all six. The stent was removed from two patients, but no recurrence has been noted so far. Conclusions ENPD and stenting are effective therapeutic choices for acute and chronic pancreatitis and pseudocysts, and they are superior to percutaneous drainage to avoid pancreatic fistula, but they may not be effective for pancreatic abscess. Selection of therapeutic methods corresponding to individual cases is important.  相似文献   
45.
Background Radiofrequency (RF) ablation for the treatment of the section line prior to liver resection has been proposed as a way to reduce blood loss during hepatectomy. Our group compared hepatectomy with and without RF ablation to determine whether this technique actually reduces blood loss during liver resection and whether it affects the perioperative outcome. Method Of 151 patients who underwent a hepatectomy between January 2002 and October 2005 at the Division of Gastrointestinal Surgery in the Department of Surgery of Saitama Medical University, 48 who had a partial hepatectomy or resection of a portion of liver smaller than a single Couinaud segment were included in the study. Twenty patients who had RF-assisted hepatectomy [RF (+) group] and 28 patients who had hepatectomy without ablation [RF (-) group] were studied to compare the rates of intraoperative blood loss and the effects of RF ablation on the perioperative outcome. Results Intraoperative blood loss was significantly reduced in the RF (+) group. In contrast, the alanine aminotransferase activity in the RF (+) group was significantly elevated immediately after the operation. There was no significant difference in the incidence of postoperative complications between the groups, although bile leakage did occur in three RF (+) patients. Conclusions Our results demonstrate that the RF ablation technique can be a useful way to reduce surgical blood loss. In view of its association with severe postoperative liver damage, the technique must be applied with caution. The danger may be especially relevant to patients with chronic liver disease and decreased liver reserve.  相似文献   
46.
OBJECTIVE: Many phase II trials have shown that preoperative chemotherapy for lung cancer is feasible but associated with postoperative morbidity and mortality. However, little is known about the effect of preoperative chemotherapy on surgical stress and postoperative complications associated with surgical intervention. We evaluated the effect of preoperative chemotherapy on perioperative inflammatory cytokine production as a surgical stress marker. METHODS: The study group comprised 38 patients undergoing anatomical lung resection and mediastinal nodal dissection for clinical stage IB/II non-small cell lung cancer during the period October 2001-December 2003. Nineteen patients received a single cycle of cisplatin (80 mg/m(2)) and docetaxel (60 mg/m(2)) chemotherapy prior to surgery (neoadjuvant group), and 19 patients underwent surgery without any previous chemotherapy (control group). White blood cell and neutrophil counts and serum concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), and granulocyte colony-stimulating factor (GCSF) were determined before surgery and on postoperative days 1 and 3. Postoperative complications were reviewed. Differences were assessed by repeated analysis of variance. RESULTS: Serum concentrations of IL-6 and GCSF rose significantly on postoperative days 1 and 3 in the neoadjuvant group in comparison to concentrations in the control group, but white blood cell count, neutrophil count, and CRP did not differ between the groups. No major complication occurred in either group. CONCLUSIONS: A single cycle of cisplatin and docetaxel chemotherapy followed by surgery can exacerbate overproduction of inflammatory cytokines during the perioperative period in lung cancer patients.  相似文献   
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In order to evaluate cardiac contractile reserve, echocardiographic studies were performed on 59 patients with acquired valvular heart disease and 13 patients with atrial septal defect. After epinephrine loading, the 59 patients were classified into three groups. In group I, echocardiographically-obtained left ventricular posterior wall excursion (PWE) remained below 10 mm after the administration of 2 microgram/min epinephrine. This group included patients with PWE below 10 mm after 1 microgram/min epinephrine loading but who could not endure the 2 microgram/min infusion because of significant adverse effects. In group II, PWE was less than 10 mm before the loading, but exceeded 10 mm after the administration of 1 or 2 microgram/min epinephrine loading. In group III, PWE exceeded 10 mm without stress. The conclusions derived from our data are as follows: The PWE and mean left ventricular posterior wall velocity (mPWV) obtained by echocardiography reflect the stroke volume derived from the thermodilution technique. It is possible to estimate the cardiac contractile force in patients who have a paradoxical motion of the interventricular septum, in the preoperative and even in the early postoperative periods. Patients whose PWE and mPWV are less than 10 mm and 35 mm/sec, respectively, after 2 microgram/min loading of epinephrine (group I), are likely to have severe cardiac failure after surgery. Inotropic stimulation is considered to be a very useful indicator for prediction of cardiac contractile reserve. Patients having decreased PWE, mPWV, mVcf and EF before surgery may have arrested recovery in both short- or long-term follow-up. However, surgical treatment is recommended for these patients with low cardiac function, because some improvement can be expected after surgery.  相似文献   
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