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In defining the linear extent of a malignant tumor in a long bone, radiographs, computerized tomography, and scintigraphy are routinely employed, especially when non-ablative surgery is being considered. The drawbacks of these modalities in defining the true intracompartmental extent of disease within a bone can largely be overcome with the use of magnetic resonance imaging. We did a prospective analysis of magnetic resonance imaging in sixteen consecutive patients with a primary malignant tumor of a long bone, and it showed that this modality has clinical promise of being more precise than the other modalities in defining the true proximal and distal extent of a tumor in a long bone. Coronal images permit easier planning of surgical techniques for salvage of a limb using an allograft than do a multiplicity of transverse images.  相似文献   
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BACKGROUND: Chest computed tomography (CT) screening of patients with blunt trauma for thoracic aortic injury is controversial. This study was undertaken to determine whether CT could exclude aortic injury and be used to select patients for aortography. METHODS: Computed tomography and aortography were used to evaluate 155 patients with blunt trauma. Computed tomography scans were reviewed separately by four attending radiologists who were unaware of the patients' clinical course and angiographic findings. RESULTS: Eight of 155 patients had aortic injuries requiring operation. Computed tomography scans in five patients were read as positive by all reviewers. One scan was read as positive by three reviewers and as negative by one. Two scans were read as positive by two radiologists and as negative by two. After poor scans were excluded, the combined sensitivity of CT for detecting aortic injury was 88%, specificity was 54%, positive predictive value was 9%, and negative predictive value 99%. CONCLUSIONS: The sensitivity of CT scan for indicating the need for aortography is observer dependent. As CT manifestations of aortic injury are often subtle, CT does not reliably exclude aortic injury.  相似文献   
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Prenatal prediction of spinal muscular atrophy.   总被引:20,自引:0,他引:20       下载免费PDF全文
Spinal muscular atrophy (SMA) is a common cause of inherited morbidity and mortality in childhood. The wide range of phenotypes in SMA, uncertainty regarding its mode of inheritance, and the suggestion of linkage heterogeneity have complicated the genetic counselling of parents of affected children. The locus responsible for autosomal recessive SMA has been mapped to 5q11.2-q13.3. The most likely order of loci is cen-D5S6-(SMA,D5S125)-(JK53CA1/2,D5S112)-D5S3 9-qter, with highly polymorphic loci being identified at JK53CA1/2 and D5S39. We describe linkage studies with another highly polymorphic locus, D5S127, that is closely linked to D5S39. This genetic map can be used as the basis for genetic counselling in families with autosomal recessive SMA. Appropriate allowance can be made for sporadic cases owing to non-inherited causes and for linkage heterogeneity or misdiagnoses.  相似文献   
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Polypeptide micelles with relative molecular weights of 25,000 (p25) and 30,000 (gp30) daltons were prepared from native 22-nm hepatitis B surface antigen (HBsAg) particles. This p25/gp30 complex was alum-adsorbed, and three dosage levels (20 micrograms, 4 micrograms, and 0.8 micrograms) were administered at 0, 1, and 6 months to 51 human volunteers. Local and systemic reactions were clinically insignificant, and all vaccinees seroconverted, regardless of dose. As anticipated, antibody responses diminished as the dosage was reduced. Seroconversion rates and geometric mean antibody levels for the 20 micrograms dosage group were significantly better than those observed with a commercial vaccine and were comparable to those achieved after immunization with 40 micrograms of the intact 22-nm particles used to prepare the polypeptides. By 2 weeks, an anti-HBs response was elicited in 80% of the group receiving 20 micrograms of the polypeptide vaccine. This rapid response to immunization may be particularly beneficial for postexposure prophylaxis where the early development of immunity is advantageous.  相似文献   
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Cytogenetic studies of patients with therapy-induced acute myeloid leukemia (t-AML) have demonstrated whole chromosome loss or q-arm deletion of chromosomes 5 and/or 7 in a majority of cases. We have established two cell lines, SAML-1 and SAML-2, from two patients who developed t-AML after radiation and chemotherapy for Hodgkin disease. In both cases, the leukemia cells contained 5q deletions. SAML-1 has 58 chromosomes and numerous abnormalities, including der(1)(1qter-->1p22::5q31-->5qter), der(5)(5pter-->5q22::1p22-->1pter), +8, der(13)i(13)(q10)del(13)(q11q14.1), and t(10;11). Fluorescence in situ hybridization (FISH) with unique sequence probes for the 5q31 region showed loss of IL4, IL5, IRF1, and IL3, and translocation of IL9, DS5S89, EGR1, and CSFIR to 1p. SAML-2 has 45 chromosomes, del(5)(q11.2q31) with a t(12;13)ins(12;5), leading to the proximity of IRF1 and RB1, and complex translocations of chromosomes 8 and 11, resulting in amplification of MYC and MLL. Comparative genomic hybridization and spectral karyotyping were consistent with the G-banding karyotype and FISH analyses. Because a potential tumor suppressor(s) in the 5q31 region has yet to be identified, these cell lines should prove useful in the study of the mechanisms leading to the development of t-AML.  相似文献   
8.
The aim of the study was to evaluate the effect of cognitive intervention (information and physical exercise), on patients with long-lasting back pain referred for surgical evaluation at an orthopaedic hospital, but evaluated as unfit for surgery. One hundred and fifty-two patients were randomized to a five days intervention or control. The intervention had no significant effects on pain. At three-month follow-up, the patients in the intervention group used significantly more active strategies to cope with the back pain compared to the control group. This effect seemed to increase over time, being more pronounced at one-year follow-up evaluation.  相似文献   
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PURPOSE: Recent studies have found an association between certain TP53 mutations and resistance to anthracycline-based primary medical therapy in breast cancer. The purpose of this study was to investigate whether TP53 mutational status also might influence the response to a non-anthracycline-containing regimen in primary breast cancer. EXPERIMENTAL DESIGN: Thirty-five patients with locally advanced breast cancer were investigated for TP53 mutations before receiving combination chemotherapy with 5-fluorouracil (1000 mg/m(2) on days 1 and 2) and mitomycin (6 mg/m(2) on day 2), administered every 3 weeks for 2-10 cycles in the neoadjuvant setting. RESULTS: Mutations in the TP53 gene, in particular those affecting loop domains L2 or L3 of the p53 protein, were associated with lack of response to chemotherapy (i.e., increase in the diameter product of tumor lesion by >/=25%; P = 0.177 for all mutations and P = 0.006 for those affecting L2/L3 domains, respectively). No statistically significant correlation between TP53 LOH and response to therapy was seen. CONCLUSION: This study revealed a significant association between lack of response to 5-fluorouracil and mitomycin and mutations affecting the L2/L3 domains of the p53 protein. Together with our previous finding that such mutations predict resistance to weekly doxorubicin, our data suggest that mutations affecting this particular domain of the p53 protein may cause resistance to several different cytotoxic compounds applied in breast cancer treatment.  相似文献   
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