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91.
BACKGROUND/AIMS: The aim of this study is to give an audit of the experiences in the Institute of Experimental Surgery, at the University of Szeged, over the past 2 decades in the form of a retrospective study. METHODOLOGY: Between January 1982 and December 2001, 132 patients with benign liver tumor (adenoma: 22; focal nodular hyperplasia: 27; hemangioma: 83) were treated. A total of 112 patients underwent surgery, while 20 asymptomatic cases were merely observed. The mean age, the female/male ratio and the size of the tumor in the adenoma cases were 38.2 years, 20/2 and 7.7cm, while for focal nodular hyperplasia they were 39.4, 24/3 and 6.3cm, and for hemangioma 49.0, 62/21 and 6.5cm. The results were compared and analyzed statistically. RESULTS: Enucleation was performed in 45.4% of the patients, nonanatomical resection in 35.6%, segmentectomy in 7%, lobectomy in 3.8%, extended lobectomy in 1.5%, stitching in 4.5%, exploration in 2.3% and liver transplantation in 0.8%. The mortality was 0.8%. Complications occurred in a total of 23.5% of the cases. CONCLUSIONS: Patients with asymptomatic focal nodular hyperplasia or hemangiomas must be excluded from surgery. Surgery is indicated only when growth or severe complaints are observed. Adenomas must be resected because of the precancerous behavior and the danger of bleeding from a rupture.  相似文献   
92.
OBJECTIVE: Clinical epidemiological and echocardiographic risk factors relating to the development of a left ventricular thrombus were studied retrospectively in patients with acute myocardial infarction. METHODS AND RESULTS: The data on 1833 consecutive patients treated for acute myocardial infarction during a 10-year period were processed retrospectively. Transthoracic echocardiography was performed on each patient 65.0 +/- 5.5 hours after hospital admission. A left ventricular thrombus was detected in 145 patients (7.9%). The patients with acute myocardial infarction and a left ventricular thrombus had significantly lower frequencies of 1) myocardial infarction in their family history (3% versus 11%, respectively), 2) hospital admission within 24 hours from the onset of chest pain (17% versus 50%, respectively), 3) thrombolytic therapy (8% versus 23%, respectively) and 4) current smoking (24% and 35%, respectively) than those without a left ventricular thrombus. In contrast, anterior infarction (81% versus 38%, respectively), left ventricular dilatation (30% versus 19%, respectively), dyskinesis of the left ventricular wall (23% versus 10%, respectively), an aneurysm (22% versus 7%, respectively) and a reduced systolic left ventricular function (ejection fraction < 40%) (28% versus 17%, respectively) were more frequent in the presence of a left ventricular thrombus after myocardial infarction. Multivariate analysis of the results revealed that the presence of anterior myocardial infarction and an aneurysm is associated with significantly increased hazard ratios. On the other hand, early hospitalization and a positive family history of infarction significantly lowered the hazard ratio. The frequency of a left ventricular thrombus was significantly higher in spring and winter. CONCLUSIONS: The results presented in this paper confirm the significant hazard of certain parameters [location of infarction (anterior) and aneurysm] as concerns left ventricular thrombus formation among patients with acute myocardial infarction. Early hospitalization was found to lower the risk of thrombus formation.These echocardiographic and clinical parameters may be useful in the establishment of the individual risk of intracavital thrombus formation and may be of help in everyday medical practice.  相似文献   
93.
Dithiocarbamates (DDTC) are chemicals widely used in the form of pesticides, therapeutic and chelating agents, and scavengers. Since DDTC interfere with SH, Cu, and Zn enzymes due to chelating properties, it was of interest to clarify, in primary culture of type II alveolar pneumocytes, the effect of this compound upon enzymes of glutathione cycle, Cu, Zn-superoxide dismutase, and the membrane structure of cells. DDTC significantly inhibited the activity of superoxide dismutase and the activity of gamma-glutamyl transpeptidase, glutathione reductase, and alkaline phosphatase, whereas an increase in the activity of glutathione peroxidase was found. The membranes of pneumocytes type II were injured. Data show that DDTC adversely affected type II pneumocyte function and structure.  相似文献   
94.
BACKGROUND: Natriuretic peptide levels are associated with cardiac output and ventricular function. We hypothesized that concomitant measurement of the peptide fragments and the hemodynamic parameters could elucidate the associations of these parameters after pediatric cardiac surgery. METHODS: After approval of the institutional review board and parents' informed consent, we investigated the clinical data of eight neonates undergoing correction of transposition of the great arteries. We measured the level of N-terminal fragments of prohormones of atrial and brain natriuretic peptides (NT-proANP, NT-proBNP) preoperatively, postoperatively and 12, 24, 48, and 72 h after arrival in the intensive care unit. The hemodynamic status was assessed by transpulmonary thermodilution at the same time points. Creatinine and other laboratory values were analyzed in the first 48 h postoperatively. RESULTS: NT-proBNP levels were inversely correlated with cardiac index (CI, r = -0.47, P = 0.030), stroke volume index (r = -0.65, P = 0.005), and global end-diastolic volume index (GEDI; r = -0.63, P = 0.011). There was strong inverse correlation between the change of NT-proBNP levels and the change of CI between two consecutive measurements during the postoperative period (r = -0.79, P = 0.001). The NT-proBNP level 12 h after surgery was strongly correlated with the creatinine level of the postoperative 24th hour (r = 0.81, P = 0.014). CONCLUSIONS: NT-proBNP correlated with the hemodynamic parameters and with the severity of renal dysfunction. Therefore, NT-proBNP is a reliable indicator of the circulatory state and the severity of a low output syndrome after arterial switch operation in neonates.  相似文献   
95.
BACKGROUND: Aprotinin is a potent antifibrinolytic drug, which reduces postoperative bleeding and transfusion requirements. Recently, two observational studies reported increased incidence of renal dysfunction after aprotinin use in adults. Therefore, the aim of the study was to investigate the safety of aprotinin use in pediatric cardiac surgery patients. METHODS: Data were prospectively and consecutively collected from 657 pediatric patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The database was assessed with regard to a possible relationship between aprotinin administration and dialysis and between aprotinin and postoperative renal dysfunction [defined as 25% decrease in the creatinine clearance (Ccr) compared with the preoperative value] by propensity-score adjustment and multivariable methods. RESULTS: The incidence of dialysis (9.6% vs 4.1%; P = 0.005) and renal dysfunction (26.3% vs 16.1%; P = 0.019) was higher in patients who received aprotinin; however, propensity adjusted risk ratios were not significant [odds ratio (OR) of dialysis: 1.22; 95% confidence interval (CI) 0.46-3.22; OR of renal dysfunction 1.26; 95% CI: 0.66-1.92]. Aprotinin significantly reduced blood loss in the first postoperative 24 h. The main contributors of renal dysfunction were CPB duration, cumulative inotropic support, age, preoperative Ccr, amount of transfusion and pulmonary hypertension. CONCLUSIONS: Despite the higher incidences of renal dysfunction and failure in the aprotinin group, an independent role of the drug in the development of renal dysfunction or dialysis could not be demonstrated in pediatric cardiac patients undergoing CPB.  相似文献   
96.
The water-soluble N-methoxy-PEG-yl-, N-beta-D-glucopyranosyl- and N-beta-D-maltosylthioureido aglyco-ristocetin were prepared which, in contrast to ristocetin A, did not induce thrombocyte aggregation. The antibacterial activity of N-beta-D-maltosylthioureido aglyco-ristocetin A against MRSA was comparable to that of ristocetin A, while its activity against Enterococcus faecalis (VRE, TSE) is somewhat stronger when compared to those of vancomycin and ristocetin A.  相似文献   
97.
The objective of the study was to investigate the possible association between nausea and vomiting in early pregnancy and congenital abnormalities. The prevalence of medically-recorded severe nausea and vomiting in early pregnancy in cases with congenital abnormalities and their available matched population controls without any defect was compared in the population-based large data set of the Hungarian Case-Control Surveillance System of congenital abnormalities, 1980-1996. Of 22,843 cases with as 25 different congenital abnormality groups, 1,713 (7.5%) cases had mothers with medically recorded and treated severe nausea and vomiting during pregnancy. Of 38,151 matched population controls, 3,777 (9.9%) had mothers with severe nausea and vomiting (adjusted prevalence odds ratio (POR) with 95% CI: 0.74, 0.68-0.79). Five congenital abnormality groups: cleft lip with or without cleft palate (0.50, 0.37-0.70), posterior cleft palate (0.53, 0.32-0.89), renal a/dysgenesis (0.23, 0.06-0.96), obstructive defects of urinary tract (0.32, 0.18-0.58), and cardiovascular malformations (0.68, 0.57-0.81) had mothers with a lower prevalence of severe nausea and vomiting in pregnancy (adjusted PORs with 95% CI included in parentheses). Of 25 congenital abnormality groups, 22 had POR lower than 1. Thus in this study the mothers of cases with congenital abnormalities were 26% less likely to have had severe nausea and vomiting in early pregnancy than the mothers of population controls without congenital abnormalities.  相似文献   
98.
99.
Binding of the metabolic gamma-hydroxybutyrate (GHB) precursor succinate to NCS-382-sensitive [3H]GHB-labeled sites in crude synaptosomal or purified synaptic membrane fractions prepared from the human nucleus accumbens (NA), globus pallidus (GP) and rat forebrain has been shown. This site can be characterized by binding of ethyl hemisuccinate and gap-junction blockers, including carbenoxolone hemisuccinate and beta-GRA. There was no significant binding interaction between GABAB receptor ligands (CGP 55845, (R)-baclofen) and these [3H]GHB-labeled sites. GHB, NCS-382 and succinate binding profile of [3H]GHB-labeled sites in rat forebrain, human NA or GP synaptic membranes were similar. The synaptic fraction isolated from the rat forebrain was characterized by GHB binding inhibition constants: Ki,NCS-382 = 1.2 +/- 0.2 microM, Ki,GHB = 1.6 +/- 0.3 microM and Ki,SUCCINATE = 212 +/- 66 microM. In crude membranes containing mainly extrasynaptic membranes, distinct GHB and GABAB receptor sites were found in the NA. By contrast, extrasynaptic GABAB receptor sites of rat forebrain and GP were GHB- and succinate-sensitive, respectively. The heterogeneity of GABAB sites found in native membranes indicates GABAB receptor-dependent differences in GHB action. Based on these findings, we suggest that succinate (and possibly drugs available as succinate salt derivatives) can mimic some of the actions of GHB.  相似文献   
100.
Succinate (SUC), a citrate (CIT) cycle intermediate, and carbenoxolone (CBX), a gap junction inhibitor, were shown to displace [3H]gamma-hydroxybutyrate ([3H]GHB), which is specifically bound to sites present in synaptic membrane subcellular fractions of the rat forebrain and the human nucleus accumbens. Elaboration on previous work revealed that acidic pH-induced specific binding of [3H]SUC occurs, and it has been shown to have a biphasic displacement profile distinguishing high-affinity (K(i,SUC) = 9.1 +/- 1.7 microM) and low-affinity (K(i,SUC) = 15 +/- 7 mM) binding. Both high- and low- affinity sites were characterized by the binding of GHB (K(i,GHB) = 3.9 +/- 0.5 microM and K(i,GHB) = 5.0 +/- 2.0 mM) and lactate (LAC; K(i,LAC) = 3.9 +/- 0.5 microM and K(i,LAC) = 7.7 +/- 0.9 mM). Ligands, including the hemiester ethyl-hemi-SUC, and the gap junction inhibitors flufenamate, CBX, and the GHB binding site-selective NCS-382 interacted with the high-affinity site (in microM: K(i,EHS) = 17 +/- 5, K(i,FFA) = 24 +/- 13, K(i,CBX) = 28 +/- 9, K(i,NCS-382) = 0.8 +/- 0.1 microM). Binding of the Na+,K+-ATPase inhibitor ouabain, the proton-coupled monocarboxylate transporter (MCT)-specific alpha-cyano-hydroxycinnamic acid (CHC), and CIT characterized the low-affinity SUC binding site (in mM: K(i,ouabain) = 0.13 +/- 0.05, K(i,CHC) = 0.32 +/- 0.07, K(i,CIT) = 0.79 +/- 0.20). All tested compounds inhibited [3H]SUC binding in the human nucleus accumbens and had K(i) values similar to those observed in the rat forebrain. The binding process can clearly be recognized as different from synaptic and mitochondrial uptake or astrocytic release of SUC, GHB, and/or CIT by its unique GHB selectivity. The transient decrease of extracellular SUC observed during epileptiform activity suggested that the function of the synaptic target recognizing protonated succinate monocarboxylate may vary under different (patho)physiological conditions. Furthermore, we put forward a hypothesis on the synaptic activity-regulated signaling between astrocytes and neurons via SUC protonation.  相似文献   
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