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81.
1. Phospholipase A2 (PLA2) cleaves phospholipids to produce a lyso-phospholipid and free fatty acid and, in view of the biological activity of the products, PLA2 may play a role in many disease states. Lyso-phospholipids and free arachidonic acid increase in ischaemic myocardium, indicating that ischaemia activates the enzyme. 2. Plasma PLA2 activity was measured in patients with acute myocardial infarction, based on the release of labelled arachidonic acid from Escherichia coli cell membrane. Fourteen males (peak serum creatine phosphokinase (CK) above twice upper normal) were studied on day 1 (within 6 h of chest pain onset), days 2-4, and days 6-9. Normal age matched males (n = 13) were also studied. 3. Plasma PLA2 in patients with uncomplicated myocardial infarction (n = 12) was, initially, 1.14 +/- 0.10 (s.e.m.) nmol/min per mL plasma, similar to that in the normal group (1.52 +/- 0.14). On days 2-4, PLA2 activity increased to 1.94 +/- 0.18 (P less than 0.001) and this activity was correlated with the earlier peak CK level (P less than 0.02). On days 6-9, PLA2 activity was 1.49 +/- 0.13 while in two patients who developed complications and underwent open-heart surgery between the last two measurements, there were further increases to 4.22 and 4.04 nmol/min per mL. 4. The increase in plasma PLA2 in uncomplicated myocardial infarction is likely to be due to release from the damaged myocardium; whether it contributes to pathophysiology is uncertain.  相似文献   
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STUDY OBJECTIVE: To investigate the effects of hypoxia-inducible factor (HIF) inhibitors, flotation agents, barriers, and a surfactant on pneumoperitoneum-enhanced adhesions in a laparoscopic mouse model. DESIGN: Prospective randomized trial (Canadian Task Force classification I). SETTING: Department of Obstetrics and Gynecology, University Hospital Gasthuisberg, Catholic University of Leuven. SUBJECTS: One hundred fourteen female BALB/c mice. INTERVENTIONS: Adhesions were induced during laparoscopy in BALB/c female mice. Pneumoperitoneum was maintained for 60 minutes with humidified CO(2). In 3 experiments the effects of HIF inhibitors such as 17-allylamino 17-demethoxygeldanamycin, radicicol, rapamycin, and wortmanin, flotation agents such as Hyskon and carboxymethylcellulose, barriers such as Hyalobarrier gel and SprayGel, and surfactant such as phospholipids were evaluated. MEASUREMENTS AND MAIN RESULTS: Adhesions were scored after 7 days during laparotomy. Adhesion formation decreased with the administration of wortmannin (p <.01), phospholipids (p <.01), Hyalobarrier Gel (p <.01), and SprayGel (p <.01). CONCLUSIONS: These experiments confirm the efficacy of barriers and phospholipids to separate or lubricate damaged surfaces. They also confirm the role of mesothelial hypoxia in this model by the efficacy of the HIF inhibitor wortmannin.  相似文献   
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Imaging of posttraumatic brachial plexus injury   总被引:3,自引:0,他引:3  
After reviewing a series of 220 patients operated upon between 1975 and 1985 for traumatic brachial plexus injuries, the authors present the results of 103 myelographies, 48 computed tomographies (CT scans) combined with standard myelography, and 25 series of images obtained by magnetic resonance imaging (MRI). To evaluate precisely the type and level of injury, the accuracy of these three techniques was compared with clinical and operative findings. The accuracy of myelography was considered good in 84% of the cases, but 4% were evaluated as false positive results and 12% as false negative or doubtful results. The combined CT scan and myelography reduced the number of doubtful results and accuracy reached 94.25%, but they did not visualize the roots distal to the spinal foramina. MRI correlated well with CT scan images and, in addition, offered visualization of distal radicular injuries. MRI seems a promising diagnostic procedure and should also help to situate nerve grafts and check their viability.  相似文献   
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The British Society for Immunology Spring Meeting, held at the University of Bristol on April 17–19th, 1996, to mark the bicentenary of Edward Jenner's vaccination against smallpox, provided the setting for the recent meeting of the UK Materno-Fetal Immunobiology Group (MFIG). The theme for the MFIG workshop was ‘Cytokines in Reproduction’ and it was attended by over 60 delegates.  相似文献   
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Typical (TPP) and atypical (APP) perfusion patterns (PP) may be seen in ictal SPECT of patients with temporal lobe epilepsy (TLE). APP may pose problem in the lateralization of the epileptogenic zone (EZ). We aimed to investigate predictive variables for the occurrence of TPP and APP. Fifty-one TLE patients were submitted to successful anterior-mesial temporal lobectomy. Univariate (UVA) and multivariate (MVA) analysis were performed upon clinical data, distribution of interictal spikes, and ictal chronology of seizures. From MVA, a final predictive model (FPM) was determined to better predict TPP and APP. Forty patients showed TPP (78.5%) and 11 patients APP (21.5%). Accuracy of ictal SPECT was higher in the unilateral (UIS) than in the bilateral (BIS) interictal spikes group (P = 0.05). FPM showed that patients exhibiting BIS, with shorter proportion of the electrographic seizure occurring after completion of tracer injection, and longer clinical than EEG seizure duration had more APP (P = 0.003). Generalized tonic-clonic seizures did not result in more APP. We concluded that analysis of ictal SPECT in TLE requires the knowledge of TPP and APP, the distribution of interictal spikes on temporal lobes and the ictal chronology of seizures. BIS showed that beyond a more complex epileptogenicity and seizure propagation, they may also lead to APP.  相似文献   
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