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1.
The efficiency of Eurocollins or modified University of Wisconsin (UW) solution (MUW) in preserving rat livers was compared. After cold storage with one of the solutions, the livers were transplanted or perfused by collagenase for isolation of hepatocytes. Five of the 6 rats receiving a graft preserved with MUW versus none of the 6 rat receiving a graft preserved with Eurocollins solution survived 24 h or more. A significantly greater number of hepatocytes were isolated from livers preserved with MUW than from livers preserved with Eurocollins solution. This suggests a better reperfusion of MUW-preserved livers by collagenase resulting from less endothelial injury. LDH release by cultured hepatocytes, ketone body production and stimulation by glucagon were not significantly different between the two groups. These results confirm the superiority of MUW solution over Eurocollins in preserving liver grafts. They suggest that the advantage of MUW solution results from better protection of vascular endothelium rather than of hepatocytes.  相似文献   
2.

Background  

Although training and education have long been accepted as integral to disaster preparedness, many currently taught practices are neither evidence-based nor standardized. The need for effective evidence-based disaster training of healthcare staff at all levels, including the development of standards and guidelines for training in the multi-disciplinary health response to major events, has been designated by the disaster response community as a high priority. We describe the application of systematic evidence-based consensus building methods to derive educational competencies and objectives in criteria-based preparedness and response relevant to all hospital healthcare workers.  相似文献   
3.
OBJECTIVES: To characterize remaining coronary artery motion of beating pig hearts after stabilization with an 'Octopus' using an optical remote analysis technique. METHODS: Three pigs (40, 60 and 65 kg) underwent full sternotomy after receiving general anesthesia. An 8-bit high speed black and white video camera (50 frames/s) coupled with a laser sensor (60 microm resolution) were used to capture heart wall motion in all three dimensions. Dopamine infusion was used to deliberately modulate cardiac contractility. Synchronized ECG, blood pressure, airway pressure and video data of the region around the first branching point of the left anterior descending (LAD) coronary artery after Octopus stabilization were captured for stretches of 8 s each. Several sequences of the same region were captured over a period of several minutes. Computerized off-line analysis allowed us to perform minute characterization of the heart wall motion. RESULTS: The movement of the points of interest on the LAD ranged from 0.22 to 0.81 mm in the lateral plane (x/y-axis) and 0.5-2.6 mm out of the plane (z-axis). Fast excursions (>50 microm/s in the lateral plane) occurred corresponding to the QRS complex and the T wave; while slow excursion phases (<50 microm/s in the lateral plane) were observed during the P wave and the ST segment. The trajectories of the points of interest during consecutive cardiac cycles as well as during cardiac cycles minutes apart remained comparable (the differences were negligible), provided the hemodynamics remained stable. Inotrope-induced changes in cardiac contractility influenced not only the maximum excursion, but also the shape of the trajectory. Normal positive pressure ventilation displacing the heart in the thoracic cage was evident by the displacement of the reference point of the trajectory. CONCLUSIONS: The movement of the coronary artery after stabilization appears to be still significant. Minute characterization of the trajectory of motion could provide the substrate for achieving motion cancellation for existing robotic systems. Velocity plots could also help improve gated cardiac imaging.  相似文献   
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Medifoxamine, an antidepressant agent which has an original chemical structure, has been shown through in vitro studies, utilising radioligand binding in tissue homogenates, to bind with moderately high affinity to 5-HT1c and 5-HT2 receptor subtypes and to 5-HT uptake sites (IC50 950, 980, and 1,500 nM, respectively). It has been shown to bind in vivo to rat brain 5-HT2 receptors after acute treatment with high dose (50 mg/kg, i.e., 133.9 μmol/kg). After 14 days continuous treatment with low dose (20 mg/kg, 53.6 μmol/kg), a decrease in the capacity of [3H]-5-HT uptake and a dose-dependent down-regulation of 5-HT2 receptors in rat cerebral cortex were observed. These results indicate that medifoxamine, which has been shown previously to act through dopaminergic systems, interacts also with central serotonergic neurotransmission and particularly with the 5-HT2 receptors, which could contribute to its antidepressant effect.  相似文献   
6.
Tension pneumomediastinum after severe vomiting in a 21-year-old female.   总被引:1,自引:0,他引:1  
A 21-year-old female with chronic membranoproliferative nephritis was admitted for suspected esophageal disruption and asthma after severe, prolonged vomiting. At the time of admission she presented with dyspnea, tachypnea, arterial hypotension and tachycardia. Physical examination showed discrete signs of ectopic air at the neck and distended cervical veins. CT-scan of the chest showed severe mediastinal emphysema with compression of the right atrium. After cervical mediastinotomy the cardiorespiratory parameters normalized immediately. Esophagoscopy showed multiple longitudinal mucosal tears between 25 and 45 cm; fluoroscopically, there was no leakage of contrast medium. Following conservative treatment the patient recovered completely and was discharged on day 8.  相似文献   
7.
8.
A 88-year-old male patient presented with fever, singultus and retrosternal pain. After 8 days of antibiotic therapy not resulting in clinical improvement, he suddenly developed a pneumopericardium. Contrast swallow and endoscopy showed intrapericardial perforation of a benign gastric ulcer. Excision of the ulcer and suturing of both the stomach and the diaphragm as well as lavage of the pericardium were done over a left thoracotomy. The patient recovered uneventfully.  相似文献   
9.
We report the case of a 51 year-old man who developed candidiasis of the small bowel associated with intestinal perforation. This condition is very rarely recognized ante mortem. Here, the diagnosis was established by pathological examination of a surgically resected specimen of small bowel at the time of surgery. A complete work-up failed to disclose any predisposing condition to digestive candidiasis. Antifungal therapy resulted in complete recovery.  相似文献   
10.
The pulmonary manifestations of varicella are observed more frequently in adults than in children. They make present according to 3 modes: acute, subacute or chronic. The authors report 2 cases of chronic pulmonary manifestations in the form of diffuse, partially calcified micronodular lesions of both lung fields observed in the course of varicella in adults.  相似文献   
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