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991.
PURPOSE: We analyzed the benefits of a risk-adapted postremission strategy in adult lymphoblastic leukemia (ALL), and re-evaluated stem-cell transplantation (SCT) for high-risk ALL. PATIENTS AND METHODS: A total of 922 adult patients entered onto the trial according to risk groups: standard-risk ALL (group 1), high-risk ALL (group 2), Philadelphia chromosome-positive ALL (group 3), and CNS-positive ALL (group 4). All received a standard four-drug/4-week induction course. Patients from group 1 who achieved a complete remission (CR) after one course of induction therapy were randomly assigned between intensive and less intensive postremission chemotherapy, whereas those who achieved CR after salvage therapy were then included in group 2. Patients in groups 2, 3, and 4 with an HLA-identical sibling were assigned to allogeneic SCT. In groups 3 and 4, autologous SCT was offered to all other patients, whereas in group 2 they were randomly assigned between chemotherapy and autologous SCT. RESULTS: Overall, 771 patients achieved CR (84%). Median disease-free survival (DFS) was 17.5 months, with 3-year DFS at 37%. In group 1, the 3-year DFS rate was 41%, with no difference between arms of postremission randomization. In groups 2 and 4, the 3-year DFS rates were 38% and 44%, respectively. In group 2, autologous SCT and chemotherapy resulted in comparable median DFS. Patients with an HLA-matched sibling (groups 2 and 4) had improved DFS. Three-year DFS was 24% in group 3. CONCLUSION: Allogeneic SCT improved DFS in high-risk ALL in the first CR. Autologous SCT did not confer a significant benefit over chemotherapy for high-risk ALL.  相似文献   
992.
BACKGROUND: This study was designed to assess the protective effects of the mitochondrial adenosine triphosphate-sensitive potassium channel (KATP) opener diazoxide as an additive to heart preservation solution. METHODS: Forty isolated isovolumic buffer-perfused rat hearts were divided into four groups. Groups I and III hearts were arrested with and cold-stored in Celsior solution for 4 hr and 10 hr, respectively. In Groups II and IV, hearts underwent a protocol similar to that used in Group I and III, respectively, except that Celsior was supplemented with 100 micromol/L of diazoxide. RESULTS: The protective effects of diazoxide were primarily manifest as a better preservation of diastolic function and a reduction of myocardial edema. The improvement of postischemic systolic function was observed only after prolonged exposure to diazoxide in Group IV, compared with Group III. The endothelium-dependent and endothelium-independent coronary flow postischemic responses were not affected by the supplementation of Celsior with diazoxide. CONCLUSIONS: Pharmacologic activation of mitochondrial KATP channels seems to be an effective means of improving preservation of cold-stored hearts, which is consistent with the presumed role of these channels as end effectors of the cardioprotective preconditioning pathway.  相似文献   
993.
BACKGROUND: Cytomegalovirus (CMV) infection or reactivation is a frequent complication of renal transplantation. Diagnosis of these conditions relies on the detection of circulating antigen, or of specific IgM and/or IgG, which develop over several weeks. Evocative clinical features may be detected earlier, but lack specificity. Rapid and early changes in the partition of lymphocyte subsets could be an additional indication of pending CMV infection. METHODS: A systematic follow-up of peripheral B lymphocytes identified immunophenotypically by the determination of surface immunoglobulins (sIg), performed in 97 kidney transplant recipients, allowed to identify transient increases apparently predictive of CMV primo-infection or reactivation over the next 3 months. To better define the nature of these B cells, an extended investigation was performed for 14 prospective patients. In addition to surface Ig, membrane CD19, HLA-DR, and CD80 expression were explored. The cytoplasmic presence of mu, kappa, and lambda chains was also examined. B cell function was investigated using the ELISPOT technique, which allows an enumeration of the populations of IgG, IgA, and IgM secreting B cells. RESULTS: Retrospective analysis of the clinical outcome of the cohort of 97 patients evidenced that early transient increases in B cell levels were significantly (P<0.0001) associated with CMV infection. The same trend was noted in the smaller series of patients who benefited from a more extensive investigation of B cells, 10 of whom presented clinical or biological signs of CMV infection. Mature B cells, expressing surface Ig, CD19, DR, and CD80 are those presenting transient increases. No significant variation of preB (cmu+/kappalambda-) or activated (spot-forming) cells was evidenced in these patients. CONCLUSION: Individual examination of each patient's immune reconstitution profile allows to detect transient peaks of mature B cell during the initial immunosuppressive therapy, that appear to be predictive of oncoming CMV infection or reactivation.  相似文献   
994.
995.
OBJECTIVES: To assess the multifaceted male sexual function after pelvic ring fracture. METHODS: A cross-sectional study of male sexual function after pelvic ring fractures was conducted, using the International Index of Erectile Function (IIEF). The department of traumatology database was scanned (June 1996 to April 1999) for 30 to 70-year-old male patients with pelvic fracture. Seventy-six consecutive, literate patients were then contacted by mail. IIEF domain scores were calculated for all responders. Cappelleri's method for identification and grading of erectile dysfunction was applied for patients sexually active within the past 4 weeks. Student's t test was used to compare the domain scorings of patients with those of the control population used for the IIEF psychometric validation. Relationships between IIEF results and patient characteristics were sought by Spearman's rank correlation coefficient for quantitative variables and Student's t test for classes. RESULTS: Forty-six patients answered (60.1% response rate). Thirty-seven patients had experienced sexual intercourse in the past 4 weeks during which 11 patients (29.7%) had exhibited various degrees of impaired erection. As a whole, compared with the published controls a significant decrease in overall satisfaction (P <0.05) was demonstrated. Pubic diastasis was further related to impaired erectile function and overall satisfaction; we suggest that cavernosal nerves might be damaged at the time of diastasis. CONCLUSIONS: This study evidenced the impairment of sexual overall satisfaction after pelvic trauma and the specific decrease in erectile function and erection firmness and confidence associated with pubic diastasis. The IIEF questionnaire might be considered at the time of rehabilitation to identify those patients that could benefit from supportive treatments.  相似文献   
996.
Development of rotary blood pump technology: past, present, and future   总被引:5,自引:0,他引:5  
Even though clinical acceptance of a nonpulsatile blood flow was demonstrated almost 45 years ago, the development of a nonpulsatile blood pump was completely ignored until 20 years ago. In 1979, the first author's group demonstrated that completely pulseless animals did not exhibit any abnormal physiology if 20% higher blood flows were provided to them. However, during the next 10 years (1979-1988), minimum efforts were provided for the development of a nonpulsatile, permanently implantable cardiac prosthesis. In 1989, the first author and his team at Baylor College of Medicine initiated a developmental strategy of various types of nonpulsatile rotary blood pumps, including a 2-day rotary blood pump for cardiopulmonary bypass application, a 2 week pump for ECMO and short-term circulatory assistance, a 2 year pump as a bridge to transplantation, and a permanently implantable cardiac prosthesis. Following the design and developmental strategy established in 1989, successful development of a 2-day pump (the Nikkiso-Fairway cardiopulmonary bypass pump) in 4 years (1989-1993), a 2 week pump (Kyocera gyro G1E3 pump) in 6 years (1992-1998), and a bridge to transplant pump (DeBakey LVAD-an axial flow blood pump) in 10 years (1988-1998) was made. Currently, a permanently implantable centrifugal blood pump development program is successfully completing its initial Phase 1 program of 5 years (1995-2000). Implantation exceeded 9 months without any negative findings. An additional 5 year Phase II program (2000-2005) is expected to complete such a device that will be clinically available.  相似文献   
997.
The arterial blood pressure waveform is variable during left ventricular assistance. The aim of this study is to examine the correlation between the left ventricular assist device (LVAD) condition and the arterial blood pressure waveform in a fixed cardiac output condition using a mock circuit. This mock circulation loop was composed of an aortic compliance chamber, a left atrial compliance chamber, a pneumatic pulsatile pump as a native heart, and a rotary blood pump representing the LVAD with left atrial drainage. The Fast Fourier Transform technique was utilized to analyze the arterial blood pressure waveform and calculate the pulsatility index (PI) and the pulse power index (PPI). The PI and PPI decreased with the increase of the LVAD rotational speed, exponentially. There was a significant negative correlation between the PI, PPI, and the LVAD rotational speed, flow rate, and assist ratio. The best correlation was observed between the PPI and the assist ratio (r = 0.986). From this viewpoint, an ideal LVAD condition may be estimated from the pulsatility change of the arterial blood pressure waveform.  相似文献   
998.
Abstract: Membrane Autotransfusion System (MATS) utilizing plasmapheresis technology has been developed in our laboratory. A specially designed polyethylene hollow fiber membrane was utilized. This study was conducted to evaluate performance of the first experimental prototype, MATS-I. The results of this study showed that the MATS-I could concentrate diluted blood at 10% of the initial hematocrit concentration (HCTi) into over 40% after passing through the system at a transmembrane pressure of 70 mm Hg. Moreover, the MATS-I can continuously treat 10,000 ml of diluted blood at various HCTi levels without deteriorating its performances. Even though the MATS-I met all required performances as an autotransfusion system, several areas of improvement of the system were necessary to meet various clinical needs. The next prototype, MATS-II, can be designed based on experiences obtained from the MATS-I. The MATS is smaller, more atraumatic and continuous, and is a faster system when compared to the currently available centrifugal autotransfusion devices.  相似文献   
999.
OBJECTIVES: To assess the serious maternal morbidity during pregnancy, delivery and post partum, which led to an hospitalization in a medical or surgical intensive care unit. STUDY DESIGN: A Retrospective study was carried out on a period of ten years, from July 1986 to July 1996, in the University Teaching Hospital of Besan?on. PATIENTS: The criterions of inclusion come from the definition of the serious maternal morbidity decided by the Inserm: any admission of a pregnant woman in a medical or surgical intensive care unit in the 42 days of the post-partum, whatever the term of the pregnancy and the type of the post-partum, extra uterine pregnancy, spontaneous miscarriage and medical or voluntary abortion. METHODS: Forty-six patient's medical file hospitalized in a medical or surgical intensive care unit between July, 1st 1986 and July, 31st 1996, have been studied. RESULTS: The analysis of the cause underline the gravity of the pathologies handled with young patients and initially healthy, the short length of controlled ventilation and hospitalization, the avoidability of great number of transfer in an intensive care unit, and the lack of hospitalization due to anaesthesia. The frequency of hospitalisation in an intensive care unit during and after the pregnancy was estimated at 0.17% of lives births. CONCLUSION: The serious maternal morbidity could be an indicator of the quality of the obstetrics cares which would complete the study of the maternal mortality. The potential gravity of the complication of the pregnancy and the delivery require better care of this patients.  相似文献   
1000.
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