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1.
Summary. In recent years the continuity equation has been established as a valuable non-invasive method for calculating aortic valve area. The continuity equation cannot be used if there is calcification or sub-valvular stenosis in the left ventricle-outflow tract, because the area of the outflow trace is not circular in those cases. The authors have tested the value of a non-invasive variant of the Gorlin formula, as an alternative method of identifying severe aortic stenosis. They examined 32 consecutive patients with aortic stenosis with both methods. Seventeen patients had severe stenosis (valve area^0–7 cm2), calculated by the continuity equation. The other 15 patients had moderate stenosis (valve area 0–7–1–0 cm2). Using the non-invasive variant of the Gorlin formula, the authors were able to identify 16 of the 17 cases with severe stenosis, thus showing that the method is useful for identifying severe aortic stenosis. (P<0–001 by x2-test).  相似文献   
2.
The internal-standard method and the powder diffractometer have been applied here to the quantitative determination of urinary stone constituents by x-ray diffraction (XRD). Reference intensity ratios determined for six stone substances were used in the reduction of intensity data. Constituent concentrations calculated for 21 stones were compared with values obtained from an element-sensitive technique. We conclude that XRD analysis alone cannot be regarded as a routine technique for the quantitative characterization of uroliths, but that semiquantitative XRD analysis supplemented by accurate quantitative elemental data is more suitable for the precise determination of true stone composition.  相似文献   
3.
PURPOSE: Investigation of high-dose chemotherapy (HD-CT) followed by autologous hematopoietic stem-cell support compared with standard-dose chemotherapy (SD-CT) as adjuvant treatment in patients with primary breast cancer and 10 or more positive axillary lymph nodes. PATIENTS AND METHODS: Between November 1993 and September 2000, 307 patients were randomized to receive (following four cycles of epirubicin 90 mg/m(2) and cyclophosphamide 600 mg/m(2), intravenously every 21 days) either HD-CT of cyclophosphamide 1500 mg/m(2), thiotepa 150 mg/m(2), and mitoxantrone 10 mg/m(2), intravenously for 4 consecutive days followed by stem-cell support; or SD-CT in three cycles of cyclophosphamide 500 mg/m(2), methotrexate 40 mg/m(2), and fluorouracil 600 mg/m(2) intravenously on days 1 and 8, every 28 days. The primary end point was event-free survival. RESULTS: After a median follow-up of 3.8 years, 144 events with respect to event-free survival have been observed (HD-CT: 63 events; SD-CT: 81 events). The first event of failure (HD-CT v SD-CT) was an isolated locoregional recurrence (nine v 11), a distant failure (52 v 68), and death without recurrence (two v two). The estimated relative risk of HD-CT versus SD-CT was 0.75 (95% CI, 0.54 to 1.06; P =.095). Overall survival showed no difference (HD-CT: 40 deaths; SD-CT: 49 deaths). CONCLUSION: There was a trend in favor of HD-CT with respect to event-free survival, but without statistical significance. Further follow-up and a meta-analysis of all randomized studies will reveal the effect of HD-CT as compared with SD-CT as adjuvant treatment in high-risk primary breast cancer.  相似文献   
4.
We investigated toxicity and efficacy of in vivo T-cell depletion with anti-thymocyte globulin (ATG) as part of an intensified myeloablative conditioning regimen followed by allogeneic stem cell transplantation in patients with advanced multiple myeloma. The conditioning regimen consisted of modified total body irradiation, busulfan and cyclophosphamide (n=15) or in the case of prior dose-limiting radiotherapy of busulfan and cyclophosphamide (n=3). The median age was 44 years (range, 29-53) and the median time from diagnosis to transplant was 12 months (range, 6-144). Grade II-IV acute graft-versus-host disease (GvHD) occurred in six patients (35%). Severe grade III/IV GvHD developed in one patient (6%). Three patients died of therapy-related causes (17%). A complete remission (CR) with negative immunofixation after allogeneic transplantation was seen in eight of the evaluable patients (53%). After a median follow-up of 41 months (range, 8-84), the estimated overall survival at 6 years for all patients is 77% (CI 95%: 58-96%). The estimated progression-free survival at 6 years for all patients is 31% (CI 95%: 2-59%) and 46% (CI 95%: 9-83%) for patients with CR. In vivo T-cell depletion with ATG resulted in a low rate of severe GvHD with low treatment-related mortality, and a substantial number of long-term survivors.  相似文献   
5.
Angiostatic effects of suramin analogs in vitro   总被引:4,自引:0,他引:4  
Suramin analogs are polyanionic naphthylureas structurally related to suramin, an antitumor agent with a narrow therapeutic window. The angiostatic activities of suramin and 16 suramin analogs were investigated using an easily quantifiable in vitro angiogenesis system. In addition, the antiproliferative activities of the analogs were studied in four different human tumor cell lines and in porcine aortic endothelial cells. The suramin analogs encompassed two main structural variations, i.e. their molecular size, and the number and substitution pattern of the sulfonate groups. Some suramin analogs with a reduced number of sulfonate groups (NF062, NF289 and NF326) showed significant dose-dependent angiostatic and also antiproliferative activities. The disulfonate NF062 was superior to suramin in inhibiting HT29 and T47D tumor cells while demonstrating a similar angiostatic potential as suramin. Therefore, the sulfonate groups in the para position of the amino groups of the naphthyl residues of suramin seem to be of special importance. The very small disulfonates (NF108, NF109, NF499, NF500 and NF241) and the asymmetric compound NF520, one half of the suramin molecule, are inactive. Therefore, a minimal molecule size seems to be essential for the biological activity. Suramin is a rather rigid molecule. The highly flexible analogs (NF527, NF528 and NF529) are inactive. This indicates that the molecular rigidity is important for the biological activity.  相似文献   
6.
We successfully performed two allogeneic hematopoietic stem cell transplantations from matched unrelated donors without the use of blood-product support after treosulfan-based conditioning in two women with acute myeloid leukemia who were Jehovah's witnesses and refused transfusions of blood products.  相似文献   
7.
A 61-year-old man with Hodgkin lymphoma (mixed type), with lymph node manifestations and extranodal and bone marrow involvement in both supra- and infradiaphragmatic locations (stage 4), had dyspnea and tachycardia on echocardiography. There were pleural and pericardial effusions and thickening of the epicardium and pericardium. These findings and computed tomographic findings were suspicious for manifestations of Hodgkin lymphoma. The pericardial findings were demonstrated on F-18 fluorodeoxyglucose positron emission tomographic imaging.  相似文献   
8.
OBJECTIVE: In the present study, we evaluate our ability to predict surgical procedure repair or replacement using preoperative echocardiography. DESIGN: The reports from transthoracic echocardiographic examinations of 298 patients were analyzed and the gross anatomic lesions and the mechanisms involved were classified into one of three main groups (functional with normal valves, organic degenerated with hypermobile valve or organic degenerated without hypermobility). RESULTS: It was possible to assess the likelihood of repair in 226 patients (76%). The criteria used were institution based and reflect the surgical procedures during the study period (1995-1999). The proportion of patients undergoing repair was 58%. In patients with a high likelihood, repair was performed in 86%. The corresponding figures in the intermediate- and low-likelihood groups were 63 and 23%, respectively. Hypermobility in the posterior leaflet and functional mitral regurgitation led to repair in the majority of patients, while patients with hypermobility in the anterior or both valves more frequently underwent replacement. CONCLUSION: We conclude that it is possible to identify patients with a high likelihood of repair using transthoracic echocardiography.  相似文献   
9.
The maximal systolic velocity of the mitral annulus motion (or maximal systolic long-axis contraction velocity of the ventricle, MLACV) has been suggested as a means to assess left ventricular function. However, reference values for a wide range of age and body size are lacking. The maximal systolic velocity was studied with M-mode echocardiography using the apical four- and two-chamber views. Data are reported as the average of the measurements of four sites of the mitral annulus. Fifty-seven healthy subjects aged 6 months to 72 years were studied. In children and adolescents up to age 18, MLACV had a significant positive correlation with age, height, body surface area, weight and mitral annulus motion amplitude and a significant negative correlation with heart rate. In adults, there was a significant positive correlation between MLACV and height, mitral annulus motion amplitude and body surface area and a significant negative correlation with age and heart rate. Multiple stepwise analysis showed that the maximal systolic velocity is highly dependent on height and age in children and adolescents up to age 18, and on height in adults. The maximal long-axis contraction velocity (MLACV) can be described by the following equations: MLACV (mm s-1) = 24.0 + 0.34 x height (cm) (Standard Error of the Estimate (SEE)=10.5) in children and adolescents, and MLACV (mm s-1) = -50.5 + 0.75 x height (cm) (SEE=9.8) in adults over 18. There were significant differences between the four sites, with the highest velocity at the lateral site and the lowest velocity at the septal site. No significant difference was found between inspiratory and expiratory beats.  相似文献   
10.
Six geriatric patients are presented who were treated because of normal pressure hydrocephalus. A tentative diagnosis was made if dementia, gait disturbance, and incontinence together with a typical CAT-scan were present. In these cases an operation was carried out. After ventriculo-peritoneal shunting clinical improvements were seen in four patients. Postoperative complications were hygromas in three patients and a shunt-dislocation in another patient. A chronic subdural bleeding was recorded also in one of these patients with only a temporary success in this case. Two patients showed no clinical improvement at any time. However, in these cases additional neurologic symptoms together with typical CAT-scan changes were present. Before making a decision for an operation vascular processes and Alzheimer's disease should be ruled out.  相似文献   
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