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41.
PURPOSE: To assess the efficacy and safety of percutaneous catheter drainage combined with alcohol sclerosis in the treatment of postoperative lymphoceles. PATIENTS AND METHODS: Thirteen patients with 14 postoperative symptomatic lymphoceles were treated. Drainage catheters were inserted under ultrasound (n = 13) or computed tomographic (n = 1) guidance. Lymphocele sclerosis was performed by instilling 10-100 mL of absolute alcohol into the lymphocele cavity and aspirating the alcohol after 30 minutes. Sclerosis sessions were carried out one to three times per day, usually three times per week. Catheter sinograms were obtained and prophylactic antibiotics administered. Imaging was repeated if symptoms or signs of recurrence developed. RESULTS: Successful drainage and sclerosis were achieved in all 13 patients. One patient with a recurrence was successfully treated with repeated drainage and alcohol ablation. No adverse effects of alcohol instillation were seen. The mean duration of catheterization was 36 days (range, 17-65 days; median, 30 days). CONCLUSION: Percutaneous drainage combined with alcohol ablation is a safe and effective treatment of postoperative lymphoceles. 相似文献
42.
RJ Mayer RB Davis CA Schiffer DT Berg BL Powell P Schulman GA Omura JO Moore OR McIntyre E Frei 《Canadian Metallurgical Quarterly》1994,331(14):896-903
BACKGROUND: About 65 percent of previously untreated adults with primary acute myeloid leukemia (AML) enter complete remission when treated with cytarabine and an anthracycline. However, such responses are rarely durable when conventional postremission therapy is administered. Uncontrolled trials have suggested that intensive postremission therapy may prolong these complete remissions. METHODS: We treated 1088 adults with newly diagnosed AML with three days of daunorubicin and seven days of cytarabine and randomly assigned patients who had a complete remission to receive four courses of cytarabine at one of three doses: 100 mg per square meter of body-surface area per day for five days by continuous infusion, 400 mg per square meter per day for five days by continuous infusion, or 3 g per square meter in a 3-hour infusion every 12 hours (twice daily) on days 1, 3, and 5. All patients then received four courses of monthly maintenance treatment. RESULTS: Of the 693 patients who had a complete remission, 596 were randomly assigned to receive postremission cytarabine. After a median follow-up of 52 months, the disease-free survival rates in the three treatment groups were significantly different (P = 0.003). Relative to the 100-mg group, the hazard ratios were 0.67 for the 3-g group (95 percent confidence interval, 0.53 to 0.86) and 0.75 for the 400-mg group (95 percent confidence interval, 0.60 to 0.94). The probability of remaining in continuous complete remission after four years for patients 60 years of age or younger was 24 percent in the 100-mg group, 29 percent in the 400-mg group, and 44 percent in the 3-g group (P = 0.002). In contrast, for patients older than 60, the probability of remaining disease-free after four years was 16 percent or less in each of the three postremission cytarabine groups. CONCLUSIONS: These data support the concept of a dose-response effect for cytarabine in patients with AML who are 60 years of age or younger. The results with the high-dose schedule in this age group are comparable to those reported in similar patients who have undergone allogeneic bone marrow transplantation during a first remission. 相似文献
43.
SI Vataev GP Dem'ianenko ES Titkov GA Oganesian 《Canadian Metallurgical Quarterly》1996,32(4):434-439
The wakefulness-sleep cycle characteristics changes in Wistar line rats after unilateral lesions of the neuronal elements of the caudate nucleus head with kainic acid (at sparing the conducting ways going through this structure) were studied. It was shown that in 4 days after acid injection the share of the active wakefulness and light slow-wave sleep is significantly increased, whereas the percentage of the passive wakefulness, deep slow-wave stage, and paradoxal sleep (up to 80%) is reduced. The wakefulness-sleep cycle in rats is completely normalized on the 7th day after injection. The obtained data allow to consider the caudate nucleus as a modulator for wakefulness-sleep cycle, that is the structure involved in the motive activity regulation. 相似文献
44.
Recent reports on the treatment of chylothorax postulate a benefit to ventilator therapy, especially using positive end-expiratory pressure (PEEP). This report describes the use of mechanical ventilation with PEEP in the management of a 24-year-old male motorcyclist who sustained a ligamentous Chance fracture of the thoracic spine at the T6-7 level with bilateral traumatic chylothorax. Treatment of the chylothorax consisted of high PEEP ventilation, bilateral chest tube thoracostomies, and total parenteral nutrition. The chylothoraces resolved within 4 days of treatment and mechanical ventilation was stopped. Ventilator therapy of traumatic chylothorax and the physiologic grounds for its use are discussed. A review of the literature and experimental evidence seem to suggest that ventilator treatment of traumatic chylothoraces is effective. 相似文献
45.
RL Conhaim SD Cooler AM McGrath DA DeAngeles GA Myers BA Harms 《Canadian Metallurgical Quarterly》1998,158(4):1204-1212
Diaspirin crosslinked hemoglobin (DCHb) is a new blood substitute manufactured from human blood. To evaluate its microvascular filtration properties, we infused DCLHb into unanesthetized sheep (10%, 20 ml/kg) and measured the flow and composition of lung and soft tissue lymph. For comparison, we also infused human serum albumin (HSA; 10%, 20 ml/kg). DCLHb raised systemic and pulmonary arterial pressures from baseline values of 83 +/- 7 and 13 +/- 2 mm Hg, respectively, to peak values of 113 +/- 9 and 26 +/- 3 mm Hg (p < 0.05 versus baseline). These increases were significantly greater than those associated with HSA, which raised systemic and pulmonary arterial pressures from baseline values of 86 +/- 4 and 13 +/- 2 mm Hg, respectively, to peak values of 97 +/- 3 and 21 +/- 7 mm Hg (p <= 0.05 versus baseline and versus DCLHb). These differences reflect the known pressor properties of DCLHb. Accordingly, DCLHb raised lung and soft tissue lymph flows to peak values of 12.2 +/- 3.8 and 1.6 +/- 0.7 ml/30 min, respectively, while HSA raised lung and soft tissue lymph flows to peak values of 7.5 +/- 4.8 and 4.6 +/- 1.9 ml/30 min, respectively (p <= 0.05 versus DCLHb). The half-times of DCLHb equilibration from plasma into lung and soft tissue lymph of 1. 0 +/- 0.3 and 2.1 +/- 1.1 h, respectively, were significantly faster than HSA equilibration half-times of 3.1 +/- 0.2 and 3.8 +/- 0.9 h. Filtration differences between DCLHb and HSA appear to be due to the pressor properties DCLHb. 相似文献
46.
GL Alonso DA González D Takara MA Ostuni GA Sánchez 《Canadian Metallurgical Quarterly》1998,1405(1-3):47-54
The sarcoplasmic reticulum Ca-ATPase is fully activated when approximately 1 microM [Ca2+] saturates the two transport sites; higher [Ca] inhibits the ATPase by competition of Ca-ATP with Mg-ATP as substrates. Here we describe a novel effect of EGTA and other chelators, raising the possibility of an additional activating effect of Ca in the sub- or low microM range. Sarcoplasmic reticulum membranes were isolated from rabbit skeletal muscles. The ATPase activity was measured after incubation at 37 degreesC in 3 mM ATP, 3 mM MgCl2, 50 mM MOPS-Tris (pH 7.2), 100 mM KCl, and variable CaCl2, EGTA and calcimycin. In the absence of added EGTA and Ca the ATPase activity is high due to contaminant Ca. The determination of the ATPase activity in the presence of increasing amounts of EGTA, without added Ca, yields a decreasing sigmoidal function. Ki ranged between 20 and 100 microM, depending on the enzyme concentration. Pi production is linear with time for several [EGTA] yielding suboptimal ATPase activities, which are inhibited by thapsigargin. These suboptimal Ca-ATPase activities are inhibited by preincubation of the enzyme in EGTA, at pH 7.2. This effect increases upon increasing EGTA concentration and preincubation time. The inhibitory effect of the previous exposure of the enzyme to EGTA is partially but significantly reverted by increasing [Ca2+] during incubations. Calcimycin and EDTA have similar effects as EGTA when added in preincubations. The effect of calcimycin is fully reverted by optimal [Ca2+] in incubations. The effects of EGTA, EDTA and calcimycin in preincubation are not additive. The results suggest that an additional calcium, lost during preincubations from a site with affinity near 1 microM, is necessary for full activation of the ATPase. 相似文献
47.
BP Imholz W Wieling GA van Montfrans KH Wesseling 《Canadian Metallurgical Quarterly》1998,38(3):605-616
We review the Finapres technology, embodied in several TNO-prototypes and in the Ohmeda 2300 and 2300e Finapres NIBP. Finapres is an acronym for FINger Arterial PRESsure, the device delivers a continuous finger arterial pressure waveform. Many papers report on the accuracy of the device in comparison with intra-arterial or with noninvasive but intermittent blood pressure measurements. We compiled the results of 43 such papers and found systolic, diastolic and mean accuracies, in this order, ranging from -48 to 30 mmHg, from -20 to 18 mmHg, and from -13 to 25 mmHg. Weighted for the number of subjects included pooled accuracies were -0.8 (SD 11.9), -1.6 (8.3) and -1.6 (7.6) mmHg respectively. Subdividing the pooled group according to criteria such as reference blood pressure, place of application, and prototype or commercial device we found no significant differences in mean differences or SD. Measurement at the finger allows uninterrupted recordings of long duration. The transmission of the pressure pulse along the arm arteries, however, causes distortion of the pulse waveform and depression of the mean blood pressure level. These effects can be reduced by appropriate filtering, and upper arm 'return-to-flow' calibration to bring accuracy and precision within AAMI limits. For the assessment of beat-to-beat changes in blood pressure and assessment of blood pressure variability Finapres proved a reliable alternative for invasive measurements when mean and diastolic pressures are concerned. Differences in systolic pressure are larger and reach statistical significance but are not of clinical relevance. Finger arteries are affected by contraction and dilatation in relation to psychological and physical (heat, cold, blood loss, orthostasis) stress. Effects of these phenomena are reduced by the built-in Physiocal algorithm. However, full smooth muscle contraction should be avoided in the awake patient by comforting the patient, and covering the hand. Arterial state can be monitored by observing the behaviour of the Physiocal algorithm. We conclude that Finapres accuracy and precision usually suffice for reliable tracking of changes in blood pressure. Diagnostic accuracy may be achieved with future application of corrective measures. 相似文献
48.
MS Lefcoe GA Fox DJ Leasa RK Sparrow DG McCormack 《Canadian Metallurgical Quarterly》1994,105(3):885-887
Sixty-six supine portable chest radiographs done on the day of bronchoscopy in 62 critical care unit patients suspected of having pneumonia were examined in a blinded fashion by two radiologists. Quantitative culture results obtained from protected brush catheter (PBC) specimens were compared with chest radiograph scores. For one observer, the sensitivity of the chest radiograph for predicting the presence of positive culture results was 0.60, specificity was 0.29, overall agreement was 0.41, positive predictive value was 0.34, and negative predictive value was 0.55. For the second observer, the values were as follows: sensitivity, 0.64; specificity, 0.27; overall agreement, 0.41; positive predictive value, 0.35; and negative predictive value, 0.55. The kappa statistic was calculated at 0.27 indicating marginal interobserver reproducibility. We conclude the portable chest radiograph in the critical care setting is not accurate in predicting the presence of pneumonia when the diagnosis is based on quantitative cultures obtained from protected brush catheter specimens. 相似文献
49.
We report the generation of action potentials in crayfish neurons by magnetic pulses for analytical purposes. A copper wire toroid, containing a ferrite core, was placed around the nerve bundle, and square wave current pulses were sent through the wire to generate a magnetic field. The magnetic field generated an action potential in the neuron that was detected downfield by a pickup microelectrode. The biosensor was used to detect local anesthetics by monitoring the time necessary for complete blockage of the action potential. Techniques for improving the efficiency and lifetimes of neural biosensors are discussed. 相似文献
50.
A Marie-Cardine LR Hendricks-Taylor NJ Boerth H Zhao B Schraven GA Koretzky 《Canadian Metallurgical Quarterly》1998,273(40):25789-25795
It has previously been reported that in resting T-lymphocytes the protein tyrosine kinase p59 constitutively co-precipitates with four phosphoproteins of 43, 55, 85, and 120 kDa, respectively. We have recently cloned the 55-kDa protein that was termed Src kinase-associated phosphoprotein of 55 kDa (SKAP55). Here we demonstrate that the recently characterized SH2-domain-containing leukocyte protein 76-associated phosphoprotein of 130 kDa (SLAP-130) is one of the components of the Fyn complex and that it also co-precipitates with SKAP55 in human T-cells. We establish that SKAP55 and SLAP-130 associate with each other when both molecules are co-expressed in COS cells. By co-transfection of truncated mutants of SKAP55 and SLAP-130 as well as by using the two-hybrid selection system, we further demonstrate that the association between SLAP-130 and SKAP55 is direct and involves the Src homology 3 domain of SKAP55 and the proline-rich sequence of SLAP-130. 相似文献