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41.
Linker  CA; Ries  CA; Damon  LE; Rugo  HS; Wolf  JL 《Blood》1993,81(2):311-318
We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML.  相似文献   
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Dentistry is rapidly entering a new era of evidence-based practice, and society is demanding prevention and treatment that has been proven to be effective in terms of meaningful health outcomes. Practitioners, individual patients and the public need randomized controlled trials because they provide the highest level of scientific evidence to change clinical practice and inform public health policy. Well-designed randomized controlled trials are conceptually simple but deceptively complex to design, implement and translate into clinical practice. Randomized controlled trials are fundamentally different from observational clinical research because they randomly assign volunteers to receive test or control interventions, they are prospective and the success of the test intervention is based on a meaningful clinical outcome that is specified before the trial begins. To be successful, randomized controlled trials must be carefully designed and powered to answer a specific question that will be generalizable to the population under study. Randomized controlled trials can be designed to evaluate efficacy, effectiveness, superiority, equivalence or noninferiority. Prominent issues and challenges in designing and conducting randomized controlled trials include carefully defining enrollment criteria, establishing an organizational infrastructure, use of a data-coordinating center, developing a manual of procedures, obtaining informed consent, recruiting and ensuring the safety of volunteer subjects, ensuring data quality, analysis and publication of trial outcomes, and translating results into clinical practice.  相似文献   
44.
Purpose

Intraforaminal ligaments (IFL) are of great interest to anatomists and clinicians to fully understand the detailed anatomy of the neuroforamina and to diagnose unclear radicular symptoms. Studies published until now have described radiological imaging of the IFLs using magnetic resonance imaging (MRI) on donor bodies. In the present study, we investigated the detectability of lumbar IFLs in vivo in adults using the high spatial resolution of the constructive interference in steady state (CISS) sequence.

Methods

A total of 14 patients were studied using a 1.5 T MRI scanner. The lumbar spine was imaged using the parasagittal CISS sequence, and the detectability of the IFLs was assessed for each lumbar level. All image datasets were analyzed by a radiologist, an orthopedic surgeon, and an anatomist. Interrater reliability was expressed as Fleiss’ Kappa. Using a single data set, a three-dimensional (3D) model was created to map the location of the IFLs within the intervertebral foramen (IF) and the immediate surrounding vessels.

Results

Overall, the radiologist was able to detect IFLs in 60% of all imaged IFs, the orthopedic surgeon in 62%, and the anatomist in 66%. Fleiss’ Kappa for the various segments varies from 0.71 for L4/5 up to 0.90 for L3/4.

Conclusion

Lumbar IFLs were successfully detected in vivo in every patient. The detection frequency varied from 42–86% per IF. We demonstrated reproducible imaging of the IFLs on MRI, with good interrater reliability. The present study was a launching point for further clinical studies investigating the potential impact of altered IFLs on radicular pain.

  相似文献   
45.

Abstract

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Introduction

Solitary bone plasmacytoma (SP) is a rare diagnosis for which the primary treatment is local radiotherapy. There is no established consensus suggesting a total spondylectomy in spinal SP.

Materials and Methods

We report the case of a 43-year-old woman with solitary plasmacytoma of the lumbar spine treated with complete vertebral resection. Radiographs, CT scan and MRI showed a single osteolytic lesion of the third lumbar vertebra. Further diagnostics following recommended algorithm for tumour screening were negative. Two times, biopsy showed no histological pathologies. Due to the instability of the spine with suspicious unknown lesion, we decided to perform a dorsal lumbar approach and instrumentation with complete resection of the posterior parts to prepare for a complete resection if mandatory. Resamples were taken and the bone surfaces sealed. Consecutive findings were positive for plasma cell infiltration of the respective vertebra, however not on the first pass, but after diagnostic pathological reference. Surgery was completed by total spondylectomy. Reference histological findings with restaging and cytogenetic risk analysis confirmed a non-high-risk solitary bone plasmacytoma, and the patient was scheduled for localized radiotherapy with 40 Gy.

Results

Follow-up examinations (53 months) showed no local recurrence or disease progression.

Discussion

There is no consensus in the literature regarding appropriate surgical approach and perioperative strategies in the treatment of solitary plasmacytoma. The finding of a solitary plasmacytoma of the spine was the determining factor for our decision to perform radical surgery with subsequent radiotherapy. The rationale for the chosen approach was to minimize the risk of local recurrence and to avoid conversion into multiple myeloma. The follow-up with 53 months is limited. However, discussion remains, if radical surgery in addition to local radiotherapy could be an alternative therapeutic approach depending on paraclinical parameters, age and cytogenetic risk analysis.  相似文献   
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A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions.  相似文献   
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Serum markers detect the presence of liver fibrosis: a cohort study   总被引:47,自引:0,他引:47  
BACKGROUND & AIMS: Histologic examination of a liver biopsy specimen is regarded as the reference standard for detecting liver fibrosis. Biopsy can be painful and hazardous, and assessment is subjective and prone to sampling error. We developed a panel of sensitive automated immunoassays to detect matrix constituents and mediators of matrix remodeling in serum to evaluate their performance in the detection of liver fibrosis. METHODS: In an international multicenter cohort study, serum levels of 9 surrogate markers of liver fibrosis were compared with fibrosis stage in liver biopsy specimens obtained from 1021 subjects with chronic liver disease. Discriminant analysis of a test set of samples was used to identify an algorithm combining age, hyaluronic acid, amino-terminal propeptide of type III collagen, and tissue inhibitor of matrix metalloproteinase 1 that was subsequently evaluated using a validation set of biopsy specimens and serum samples. RESULTS: The algorithm detected fibrosis (sensitivity, 90%) and accurately detected the absence of fibrosis (negative predictive value for significant fibrosis, 92%; area under the curve of a receiver operating characteristic plot, .804; standard error, .02; P < .0001; 95% confidence interval, .758-.851). Performance was excellent for alcoholic liver disease and nonalcoholic fatty liver disease. The algorithm performed equally well in comparison with each of the pathologists. In contrast, pathologists' agreement over histologic scores ranged from very good to moderate (kappa = .97-.46). CONCLUSIONS: Assessment of liver fibrosis with multiple serum markers used in combination is sensitive, specific, and reproducible, suggesting they may be used in conjunction with liver biopsy to assess a range of chronic liver diseases.  相似文献   
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