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11.
The capacity of a radiofrequency, 13.56 MHz, capacitive hyperthermia system using extensive pre-cooling of the subcutaneous tissue to induce locoregional deep heating has been investigated in 11 patients. Tumour location was presacral in nine--and eccentric towards the lateral side of the pelvis in two patients. For thermometry multiple catheters (mean 2.7) were inserted into the treatment volume. The mean numbers of temperature measuring points per treatment were 9.4 in tumour, 5.5 in muscle and 7.2 in subcutaneous fat. RF energy was applied after 30 min of cooling through two flexible boli perfused with saline water at 5-10 degrees C. Patient tolerance to pre-cooling was very good and after some initial discomfort the patient became rapidly accustomed to the cold water boli. For some patients better temperatures were achieved when the conventional anterior-posterior applicator set-up was replaced by a set-up with an applicator on each lateral side of the patient. As patients can tolerate temperatures within the fat tissue as high as 45.5 degrees C without complaining it appears important to monitor the temperature at the transition of fat to muscle tissue to prevent subcutaneous burns. The study shows that pre-cooling cannot avoid preferential heating at the interface from fat to muscle tissue. In this patient group the quality of the hyperthermia treatment appeared to be rather poor: 60% of the measured tumour temperatures were below 40 degrees D.  相似文献   
12.
In hypoxemic intrauterine growth-retarded fetuses (IUGR) there is a reduction in the incidence of fetal movements and in fetal heart rate variation. A causal relationship with the impairment of fetal oxygenation has been suggested. In 16 IUGR fetuses and in 13 normally grown fetuses maternal hyperoxygenation was applied for 40 min to increase fetal PO2 levels. All IUGR fetuses had abnormal Doppler blood velocity waveforms of the umbilical artery suggesting an impaired uteroplacental exchange. The effect of hyperoxygenation on fetal breathing and body movements and on fetal heart rate was evaluated. In the IUGR fetuses there was a significant increase in fetal breathing and body movements and in heart rate variation during hyperoxygenation as compared to the preceding control period of 40 min. No significant changes in fetal breathing and body movements were found in the normally grown control fetuses. A surprising observation was the increase of the number of heart rate decelerations after discontinuation of the maternal hyperoxygenation. It is concluded that in IUGR fetuses the increase in fetal heart rate variation and the increase in the incidence of breathing and body movements during maternal hyperoxygenation substantiates the relationship between these variables and the oxygenation status of the fetus.  相似文献   
13.
OBJECTIVE--To test in patients with a history of myocardial infarction or stroke the feasibility of four quality of life measurements--the Nottingham health profile (NHP), the heart patients psychological questionnaire (HPPQ), the sickness impact profile (SIP), and the hospital anxiety and depression scale (HAD). DESIGN--Subjects were tested and retested after an interval of 14 days: questionnaires were self assessed. SUBJECTS--Participants were randomly selected from the Rotterdam stroke data bank (stroke patients; n = 16, mean (SD) age 66.0 (11.0) years and from the population based Rotterdam study (myocardial infarction; n = 20, mean (SD) age 72.7 (7.9) years, controls; n = 17, mean (SD) age 72.8 (7.3) years. MEASUREMENTS AND MAIN RESULTS--Mean (SD) administration times for the NHP, HPPQ, SIP, and HAD were 7.9 (3.5), 10.5 (4.3), 21.0 (9.8), and 5.5 (2.8) minutes respectively. On average, the test-retest reliability was good, with Spearman correlations ranging from 0.31 to 0.95. In spite of the limited size of the study, all instruments were able to show differences between the study groups. For instance, median SIP total scores for myocardial infarction and stroke patients were 12.4 (interquartile range 7.0-19.1) and 11.4 (5.9-15.4) respectively, compared with 7.7 (3.7-11.3) in the control group (p values of 0.04 and 0.14 respectively). CONCLUSIONS--This study suggests that use of the four instruments tested may be feasible and reliable for assessing aspects of quality of life in patients with a history of a myocardial infarction or stroke.  相似文献   
14.
To identify high-risk patients with acute myocardial infarction, we compared admission values of two-dimensional echocardiography and hemodynamic monitoring. Left ventricular wall motion score (WMS), left ventricular stroke work index (LVSWI), and pulmonary capillary pressure (PCP) were obtained in 77 patients without clinical signs of heart failure. Progression into Killip grade 3 or 4 was found in 16 of 77 patients (21%) within 32 +/- 6 hours (mean +/- 1 standard deviation) after admission. Mean WMS, LVSWI, and PCP in those patients who developed severe pump failure were significantly different from those who did not: 13.4 +/- 4.9 versus 7.3 +/- 4, 30 +/- 4 versus 46 +/- 11 gm/m2, and 21 +/- 8 versus 12 +/- 6 mm Hg, respectively. Sensitivity of WMS of greater than 7 and LVSWI of less than 35 gm/m2 in predicting Killip grade 3 or 4 was 88% and 94%, specificity was 57% and 87%, positive predictive value was 35% and 65%, and negative predictive value was 95% and 98%. Sensitivity of PCP was low (50%). Early identification of patients developing myocardial rupture or reinfarction was limited by both methods. We conclude that echocardiographic examination on admission in patients with acute myocardial infarction provides an alternative approach for early identification of low-risk patients.  相似文献   
15.
OBJECTIVE: To investigate whether pathological changes in the umbilical artery (UA), ductus venosus (DV) and short-term fetal heart variation are related to perinatal outcome in severe, early intrauterine growth restriction (IUGR). METHODS: This multicenter, prospective, longitudinal, observational study was carried out in the Departments of Fetal Medicine and Obstetrics in Hamburg, Amsterdam, Utrecht and London. In 70 singleton pregnancies with IUGR fetuses, delivered at 26-33 weeks of gestation because of antepartum fetal distress, short-term variation (STV) of fetal heart rate, pulsatility index of the fetal UA (UA PI) and DV pulsatility index for veins (DV PIV) were assessed at least weekly. The final measurement was performed within 24 h of delivery. Standard cut-off levels (2 SD or 3 SD, absent flow or reversed flow) were used and new cut-off levels were calculated by means of receiver-operating characteristics analysis. Adverse outcome was defined as perinatal death, cerebral hemorrhage (> or = Grade II) or bronchopulmonary dysplasia before discharge. The predictive value for adverse outcome was calculated for different cut-off levels of the monitoring parameters, adjusted for gestational age (GA), by multivariate logistic regression analysis. Data were analyzed separately for three different time blocks, namely 8-14, 2-7 and 0-1 days before delivery. RESULTS: Adverse perinatal outcome occurred in 18/70 (26%) infants. During the last 24 h before delivery DV PIV and UA PI were significantly higher and STV lower in the adverse outcome group, while 2-7 days before delivery only DV PIV was significantly higher. Adverse perinatal outcome could be predicted at 0-1 days before delivery by DV PIV at a cut-off of three multiples of the SD (odds ratio (OR) 11.3; 95% CI 2.3-57) and GA (OR 0.4; 95% CI 0.3-0.8), at 2-7 days by DV PIV at 2 SD (OR 3.0; 95% CI 0.8-12) and GA (OR 0.5; 95% CI 0.3-0.8) and at 8-14 days by DV PIV at 2 SD (OR 3.9; 95% CI 0.8-20) and GA (OR 0.5; 95% CI 0.3-0.8). Other parameters did not contribute to the multivariate model. CONCLUSIONS: DV PIV measurement is the best predictor of perinatal outcome. This measurement may be useful in timing the delivery of early IUGR fetuses and in improving perinatal outcome, even when delivery may be indicated at an earlier GA. However, as GA was also an important factor influencing outcome, with poorer outcome at earlier gestation at delivery, this hypothesis needs to be tested in a multicenter, prospective, randomized trial.  相似文献   
16.
An 80-year-old woman was evaluated by transesophageal echocardiography after coronary artery bypass surgery and subsequent cardioembolic stroke. In addition to spontaneous echo contrast demonstrating a counterclockwise rotating blood flow pattern, we observed free vortex ring formation in the left atrium, originating in the left auricle. To our knowledge, this is the first reported case of abnormal free vortex ring type flow pattern in the left atrium.  相似文献   
17.
OBJECTIVE: to determine the societal cost-effectiveness of various management strategies, including both the diagnostic imaging work-up and treatment, for patients with intermittent claudication in The Netherlands. METHODS: a decision-analytic model was used and included probability and quality of life data available from the literature. A cost-analysis was performed in a university setting in The Netherlands. Imaging work-up options included magnetic resonance angiography (MRA), color-guided duplex ultrasound, or intraarterial digital subtraction angiography (DSA) and treatment options were percutaneous transluminal angioplasty with selective stent placement if feasible or bypass surgery. Management strategies were defined as combinations of imaging work-up and treatment options. A conservative strategy with no imaging work-up and walking exercises was considered as reference. Main outcome measures were quality-adjusted life years (QALYs), lifetime costs (euro), and incremental cost-effectiveness (CE) ratios. The base-case analysis evaluated 60-year-old men with severe unilateral intermittent claudication of at least one year duration. RESULTS: the range in QALYs and costs across management strategies that considered angioplasty as only treatment option was small (maximum difference: 0.0033 QALYs and 451 euros). Similarly, the range was small across management strategies that considered angioplasty if feasible otherwise bypass surgery (maximum difference: 0.0033 QALYs and 280 euros). MRA in combination with angioplasty (6.1487 QALYs and 8556 euros) had a CE ratio of 20,000 euros/QALY relative to the conservative strategy. The most effective strategy was DSA in combination with angioplasty if feasible otherwise bypass surgery (6.2254 QALYs and 18,583 euros) which had a CE ratio of 131,000 euros/QALY relative to MRA in combination with angioplasty. CONCLUSION: the results suggest that the imaging work-up with non-invasive imaging modalities can replace DSA for the work-up of patients with intermittent claudication without a substantial loss in effectiveness and a minimal cost-reduction. Management strategies including angioplasty are cost-effective in the Netherlands but although strategies including bypass surgery are more effective, their incremental costs are very high.  相似文献   
18.
Charcot-Marie-Tooth disease caused by mutations of the myelin protein zero gene demonstrates considerable phenotypical variability. We describe a 45-year-old female with a peripheral neuropathy with demyelinating and axonal features, pes cavus and pupillary light-near dissociation. She was heterozygous for two mutations in the myelin protein zero gene (His81Tyr and Val113Phe), both present on the same allele. Our patient shows a less severe phenotype than previously described patients with a His81Arg mutation. Multiple mutations in the myelin protein zero gene, as well as Charcot-Marie-Tooth with pupillary abnormalities have previously been described in rare instances. However, concurrent occurrence of both phenomena is a novel finding.  相似文献   
19.
Transesophageal echocardiography was attempted in 59 pediatric patients with congenital heart disease in the operating room (n = 33) or during heart catheterization or in the intensive care unit (n = 26). Six different commercially available transducers were used with diameters ranging from 7 to 15 mm. Age ranged from 1 day to 16 years, and body weight ranged from 3.7 to 65 kg. Objectives of the study were to determine (1) minimum body weight in which transesophageal echocardiography with various probes is possible, (2) additional diagnostic value, and (3) potential applications. In three cases (one surgical and two nonsurgical) the probe could not be inserted. Minimum body weight was 17 to 20 kg for probes with a diameter of greater than or equal to 13 mm and approximately 12 kg for the 11 mm probes. A 7 mm probe, on the other hand, could be inserted easily in all patients (including a neonate) in whom transesophageal echocardiography was attempted. In 11 of 56 patients, additional diagnostic information was obtained. Thus, transesophageal echocardiography is feasible in the pediatric age group provided that special probes are used in small children. Additional diagnostic information can be obtained, and the technique is of value during cardiac surgery or balloon interventions for evaluation of the efficacy of the procedure and for monitoring ventricular function.  相似文献   
20.
Summary Impairment of skeletal muscle function is the common feature of distinct clinical forms of glycogenosis type II. In the present study, muscle cultures from different patients were used to investigate the cause of clinical heterogeneity and the feasibility of enzyme replacement therapy. The activity of acid -glucosidase appears to be the primary factor in determining the extent of lysosomal glycogen storage in muscle, and thereby the clinical severity of the disease. Neutral -glucosidases do not seem influencial. Correction of the enzymatic defect was achieved in skeletal muscle cultures from patients by administration of a high-uptake form of acid -glucosidase, purified from human urine. The enzyme reaches the lysosomes, including the glycogen storage vacuoles, and the lysosomal glycogen content is reduced to control level. In normal muscle cells 20% of the total cellular glycogen pool is segregated in lysosomal compartments. This percentage is higher than in fibroblasts, which may partly explain why muscles are more prone to store glycogen. The relevance of this study for enzyme therapy is discussed.  相似文献   
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