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101.
BACKGROUND: Single-center studies suggest substantial variation in intraaortic balloon pump (IABP) utilization. Our purpose is to examine IABP utilization over time and across medical centers. METHODS: This was a prospective cohort of 29,961 consecutive patients undergoing isolated coronary artery bypass graft surgery, between 1995 and 2000, at 10 centers (eight in northern New England and two in Canada). RESULTS: A total of 2,678 (8.9%) patients received an IABP. The rate of preoperative IABP insertion was 6.3%, and that of intra- or postoperative insertion was 2.6%. During the 6 years, IABP use increased from 7.0% to 10.3% (p(trend) <0.001). Preoperative IABP insertion increased from 5.4% to 7.8% (p(trend) < 0.001). There was no significant increase in intra-/postoperative IABP insertion 1.7% to 3.4% (p(trend) = 0.34). Adjustment for changes in patient and disease characteristics did not substantially alter these results. The rate of IABP use varied substantially by center, from 5.9% to 16.4% (p < 0.001). Adjustment for patient and disease characteristics resulted in variation from 4.8% to 12.8% across the 10 centers (p < 0.001). The adjusted rates of preoperative IABP insertion varied from 3.6% to 13.7% (p < 0.001), and the rates of intra-/postoperative IABP insertion ranged from 1.0% to 5.2% (p < 0.001). There was no significant correlation between the rates of preoperative and intra-/postoperative IABP use (r(s) = 0.085, p = 0.815). CONCLUSIONS: During the 6 years, there was a 47% increase in the rate of IABP utilization. Even after adjustment, there was almost threefold variation in IABP use across centers. This variation likely reflects lack of consensus on the appropriate use of the IABP in CABG patients.  相似文献   
102.
103.
Twenty-two patients with previously treated but progressive stage IV neuroblastoma received combination therapy with vincristine (1.0 mg/m2) followed in 6 hours by bleomycin (15 mg/m2). Therapy was administered twice weekly. No responses were seen in the 19 patients who received four or more doses of the bleomycin-vincristine combination.  相似文献   
104.
Measurements of the nine components of complement in the serums of 16 members of a kindred have established the diagnosis of hereditary deficiency of the second component of complement (C2). The autosomal recessive mode of inheritance resembles that of previously described families with C2 deficiency. Both C2 activity determinations with a stoichiometric haemolytic assay and C2 protein measurements with electroimmunodiffusion against antibody monospecific for C2 detect the heterozygous deficient state. Antigenic analysis, in vitro reconstitution experiments, and the constant ratio of C2 function to C2 protein indicate that the C2 synthesized by heterozygotes is indistinguishable from normal human C2. Studies of neonatal homozygous deficient serum and maternal heterozygous deficient serum show that transplacental passage of C2 does not occur. C2 deficiency in this family is not associated with clinical defects in host resistance.  相似文献   
105.
During the past 10-15 years there has not been a significant improvement in the overall survival of children with metastatic neuroblastoma. From 1971 through 1975, 104 eligible patients were entered on two clinical studies for newly diagnosed cases of stage IV neuroblastoma by the Childrens Cancer Study Group (CCSG). Patient data from both studies were evaluated for activity of cyclophosphamide, imidazole carboxamide, and vincristine and of these same agents plus adriamycin. Response was evaluated by serial measurements of tumor size. Eighty-four patients experienced a complete or partial response. The life-table estimate of median survival on both studies was 11–12 months for all patients and 13-18 months for responders, unchanged from the results of previous CCSG studies. Long-term survival, however, for patients on these studies demonstrates a significant increase compared with results reported from the three previous CCSG studies. Children less than 1 year or greater than 6 years of age at diagnosis showed a significantly improved survival pattern over the intermediate age group. It is suggested that there is a need to consider the induction response pattern and age at diagnosis when planning a maintenance program so that nonresponders can be identified early and considered for treatment with new agents or aggressive multimodal therapy.  相似文献   
106.
107.
BACKGROUND: This study reports one cardiac surgical center's experience with off-pump coronary artery bypass (OPCAB) and compares clinical risk factors and outcomes with a group of patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass at the same institution. METHODS: Data on preoperative risk factors, intraoperative clinical markers, and postoperative outcomes were collected prospectively on all patients undergoing cardiac surgical procedures at our institution. From January 1, 1999, through October 7, 1999, 332 patients underwent OPCAB procedures at our institution. This group was compared with 445 consecutive patients undergoing CABG at the same institution during the period of January 1, 1998, through November 30, 1998. RESULTS: The two groups were similar with respect to preoperative clinical risk factors. Intraoperative data showed OPCAB patients tended to have fewer grafts performed and had a lower frequency of multiple grafts to obtuse marginal vessels. Outcomes showed no differences in the incidence of perioperative stroke, mediastinitis, reexploration for bleeding, pulmonary complications, new renal failure, postoperative atrial fibrillation, or transfusion of blood products. Patients in the OPCAB group had fewer perioperative myocardial infarctions and lower incidence of postoperative low cardiac output syndrome. A higher percentage of OPCAB patients had surgical lengths of stay of 5 days or less. The OPCAB group tended to have a lower in-hospital mortality rate but this difference did not reach statistical significance. CONCLUSIONS: Off-pump coronary artery bypass grafting with revascularization of all coronary artery segments is a safe and effective procedure that can be performed with equal or improved outcomes and shorter surgical lengths of stay compared with CABG with cardiopulmonary bypass.  相似文献   
108.
109.
Possible instabilities during cosmological recombination may produce an epoch of nonlinear density growth and fractal-like structural patterns out to the horizon scale at that epoch (approximately 200 Mpc today). With this motivation, we examine the consequences of the change in effective radiative recombination reaction rate coefficients produced by intense stimulated emission. The proton-electron recombination is considered as a natural laser, leading to the formation of spatially nonuniform distributions of neutral matter earlier than the recombination epoch.  相似文献   
110.
BACKGROUND: Concern about the possible adverse effects of the cardiopulmonary bypass (CPB) pump and advances in retractors and operative techniques to access all coronary segments have resulted in increased interest in off-pump coronary artery bypass (OPCAB) procedures. Four of the Northern New England Cardiovascular Disease Study Group centers initiated OPCAB programs in 1998. We compared the preoperative risk profiles and in-hospital outcomes of patients done off-pump with those done by conventional coronary artery bypass (CCAB) with CPB. METHODS: Between 1998 and 2000, 1,741 OPCAB and 6,126 CCAB procedures were performed at these four medical centers. Minimally invasive direct coronary artery bypass grafting procedures were excluded. Data were available for patient and disease risk factors, extent of coronary disease and adverse in-hospital outcomes. RESULTS: The OPCAB and CCAB groups were somewhat different in their preoperative patient and disease characteristics. The OPCAB patients were more likely to be female and to have peripheral vascular disease. The CCAB patients were more likely to have an ejection fraction less than 0.40 and be urgent or emergent at operation. However, overall predicted risk of in-hospital mortality, based on preoperative factors, was similar in the OPCAB and CCAB groups; the mean predicted risk was 2.6% (p = 0.567). Crude rates of mortality (2.54% OPCAB versus 2.57%, CCAB), intraoperative or postoperative stroke (1.33% versus 1.82%), mediastinitis (1.10% versus 1.37%), and return to the operating room for bleeding (3.46% versus 2.93%) did not differ significantly. The OPCAB patients did have a statistically significant reduction in the need for intraoperative or postoperative intraaortic balloon pump support (2.31% versus 3.41%; p = 0.023) and in the incidence of postoperative atrial fibrillation (21.21% versus 26.31%; p < 0.001). Adjustment for preoperative risk factors and extent of coronary disease did not substantially change the crude results. Median postoperative length of stay was significantly shorter (5 days versus 6 days, p < 0.001) for OPCAB patients than for CCAB patients. CONCLUSIONS: This multicenter study showed that patients having OPCAB are not exposed to a greater risk of short-term adverse outcomes. These data also provided evidence that patients having OPCAB have significantly lower need for intraoperative or postoperative intraaortic balloon pump, lower rates of postoperative atrial fibrillation, and a shorter length of stay.  相似文献   
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