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81.
82.
Congenital or acquired communication between left ventricle and right atrium is rare and can be easily overlooked as an eccentric tricuspid regurgitation jet. MRI is the ideal modality for accurate diagnosis, providing details for surgical planning about the location and size of the defect.  相似文献   
83.
Assembly effectors are small molecules that induce inappropriate virus capsid assembly to antiviral effect. To identify attributes of hepatitis B virus (HBV) assembly effectors, assembly reaction products (normal capsid, noncapsid polymer, intermediates, and free dimeric core protein) were quantified in the presence of three experimental effectors: HAP12, HAP13, and AT-130. Effectors bound stoichiometrically to capsid protein polymers, but not free protein. Thermodynamic and kinetic effects, not aberrant assembly, correlate with maximal antiviral activity.  相似文献   
84.
Seventeen strains of alcoholic yeasts were screened for petite mutation frequency and killer phenotypes with an objective to develop them as industrial strains. The frequency of petite mutations varied with the strain. Though some strains have shown high frequency mutations, a few strains were found to be genetically stable. The killer property was found to vary with the strains. Interestingly, though some strains proved to be sensitive, some strains were found to be killer strains for marker killer strain also. Thus, the study provides the evidence that the killer principle varies with the strain.  相似文献   
85.
One-stage surgery was successfully performed in a 44-year-old hypertensive man with uncontrolled angina, multiple coarctations of the thoracic and abdominal aorta, and a previous subtotal gastrectomy. There was a gradient of 120 mm Hg between the thoracic and abdominal aorta. A graft was placed retroperitoneally from the infrarenal aorta to the ascending aorta and was followed by a coronary artery bypass graft. Twenty-four months postoperatively, the patient was free of angina, and his hypertension was easily controlled.  相似文献   
86.
Information regarding the effectiveness of chemotherapy in cases of invasive thymoma is limited. Two patients in whom the combination of cyclophosphamide, doxorubicin, and vincristine produced remission of invasive thymoma are described. The durations of remission were eight and seven months, respectively. In both patients, recurrence was observed at the site of bulky disease, and a secondary complete response continuing for 37 months was achieved in one of them with radiation therapy.  相似文献   
87.
Early results of the extracardiac conduit Fontan operation   总被引:12,自引:0,他引:12  
BACKGROUND: Among the modifications of the Fontan operation, the extracardiac approach may offer the greatest potential for optimizing early postoperative ventricular and pulmonary vascular function, insofar as it can be performed with short periods of normothermic partial cardiopulmonary bypass and without cardioplegic arrest in most cases. In this study, we reviewed our experience with the extracardiac conduit Fontan operation, with a focus on early postoperative outcomes. METHODS AND RESULTS: Between July 1992 and April 1997, 51 patients (median age 4.9 years) underwent an extracardiac conduit Fontan operation. Median cardiopulmonary bypass time was 92 minutes and has decreased significantly over the course of our experience. Intracardiac procedures were performed in only 5 patients (10%), and the aorta was crossclamped in only 11 (22%). Intraoperative fenestration was performed in 24 patients (47%). There were no early deaths. Fontan failure occurred in 1 patient who was a poor candidate for the Fontan procedure. Transient supraventricular tachyarrhythmias occurred in 5 patients (10%). Median duration of chest tube drainage was 8 days. Factors significantly associated with prolonged resource use (mechanical ventilation, inotropic support, intensive care unit stay, and hospital stay) included longer bypass time and higher Fontan pressure. At a median follow-up of 1.9 years, there was 1 death from bleeding at reoperation. CONCLUSIONS: The extracardiac conduit Fontan procedure can be performed with minimal mortality and morbidity. Improved results may be related to advantages of the extracardiac approach and improved preservation of ventricular and pulmonary vascular function.  相似文献   
88.
Background Cardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried out to compare mortality and morbidity in the off-pump and on-pump CABG groups. Methods We prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL) pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared. Results OPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12% although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001). Conclusion There was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and hospital stay in OPCAB group.  相似文献   
89.
Velocity-encoded cine (VEC) magnetic resonance (MR) imaging is a valuable technique for quantitative assessment of flow dynamics in congenital heart disease (CHD). VEC MR imaging has a variety of clinical applications, including the measurement of collateral flow and pressure gradients in coarctation of the aorta, differentiation of blood flow in the left and right pulmonary arteries, quantification of shunts, and evaluation of valvular regurgitation and stenosis. After surgical repair of CHD, VEC MR imaging can be used to monitor conduit blood flow, stenosis, and flow dynamics. There are some pitfalls that can occur in VEC MR imaging. These include potential underestimation of velocity and flow, aliasing, inadequate depiction of very small vessels, and possible errors in pressure gradient measurements. Nevertheless, VEC MR imaging is a valuable tool for preoperative planning and postoperative monitoring in patients with CHD.  相似文献   
90.
OBJECTIVE: Following cardiac surgery, patients are transferred from the operating theatre to intensive care. This clinical environment has one nurse per patient and facilities for mechanical ventilation. Patients are kept in this setting until the following day. This practice has been challenged with early extubation of patients. At our institution we have established a fast-track policy including the following features: (1) patient selection; (2) operating list scheduling with fast-track patients first; (3) anaesthetic tailored to early extubation; (4) methodical procedure with warm cardiopulmonary bypass; (5) removal of the arterial line; (6) transfer from intensive care to a separate high dependency unit ('step-down') on the day of operation, where the ratio of nurse to patient is one to three and there are no ventilatory facilities and no invasive monitoring; or (7) to keep these patients on ICU but decrease the nurse to patient ratio. METHOD: The case notes of 572 patients who predominantly had myocardial revascularisation, undergoing this process from July 1996 to July 2000 at our institution were reviewed. RESULTS: Mean EUROSCORE for the study group was 1.42. The 30-day mortality rate for the study group was 0.34%, mean intensive care time was 5 h 52 min, mean time to extubation was 3 h 10 min, mean readmission rate to intensive care was 0.34% and mean hospital stay from day of operation (inclusive) was 5.65 days. This process increased our throughput by 14.6% (compared to standard practices). COMMENT: This study demonstrates that transfer of appropriate patients to a high dependency area from intensive care following cardiac surgery is safe. It allows intensive care beds to be used by more than one patient each day and allows significant cost savings by reducing the nursing ratio per patient.  相似文献   
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