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81.
Chordoma: role of radiation therapy   总被引:4,自引:0,他引:4  
The treatment of 21 patients with a diagnosis of chordoma seen over a 20-year period is described. The 13 men and eight women (ratio 1.6:1) ranged in age from 7 to 82 years (average, 50 years). Eleven chordomas arose from the clivus; the others originated in the sacral region (three patients), thoracic spine (one), cervical spine (three), and lumbar spine (three). Primary treatment consisted of surgery, reserving radiation therapy for recurrence in the majority of patients. Radiation doses, delivered with megavoltage equipment, ranged between 5,000 cGy delivered over 5 weeks and 6,600 cGy over 6 1/2 weeks. Irradiation produced significant tumor control, with remission of symptoms from 1 to 6 years. The combination of high-dose radiation therapy and complete or subtotal surgical resection offers the best chance for prolonged survival in this group of patients.  相似文献   
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A recently developed method for image-selected localized hydrogen-1 magnetic resonance (MR) spectroscopy was assessed in the differential diagnosis of nine primary and secondary cerebral tumors, including four gliomas, two meningiomas, one neurilemoma, one arachnoid cyst, and one metastasis of breast cancer. Well-resolved H-1 MR spectra of these tumors were obtained in vivo with a conventional 1.5-T whole-body MR imaging system. All tumor spectra were remarkably different from spectra from normal brain tissue. Spectra obtained from different tumors exhibited reproducible differences, while histologically similar tumors yielded characteristic spectra with only minor differences. The observed spectral alterations reflect variations in concentrations and relaxation times of the H-1 MR sensitive pool of free (mobile) metabolites within the tissues. In most cases, the concentrations of N-acetyl-aspartate and creatine/phosphocreatine are reduced below detectability, whereas choline-containing compounds are generally enhanced. The spectral differences between the tumors are mainly due to the differing concentrations of lipids, lactic acid, and carbohydrates. Localized H-1 MR spectroscopy may become an important clinical tool for the differentiation of tumors as well as for therapeutic control.  相似文献   
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Diabetic and ischaemic non-healing pedal ulcers have a tendency for chronicity and increased chances of infection, which may threaten the viability of the foot. Systemic administration of therapeutic agents may be insufficient in these cases. We have assessed the role of retrograde venous perfusion (RVP) for the treatment of nine diabetic and 10 ischaemic non-healing pedal ulcers. Agents used were soda bicarbonate, heparin, lignocaine, gentamicin and pentoxiphylline. Five of nine diabetic non-healing ulcers showed complete healing and the remaining four improved. The complete recovery in the cases of diabetic ulcer occurred in 10-24 days (mean 16 days), while ischaemic ulcers took 10-14 days for complete recovery (mean 13.6 days). There was a reduction of rest pain in all 10 patients with ischaemic disease; five patients showed complete healing of ulcers, and the other five improved significantly. In two patients, pre-gangrene changes were reversed. RVP is a useful adjunct to conservative or surgical treatment of non-healing pedal ulcers. Its main impact was in improving ischaemia and promoting healing.  相似文献   
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A considerable number of patients with malignancies who are treated with high-dose therapy and hematopoietic stem cell transplantation subsequently relapse. Analyses of peripheral blood stem cell (PBSC) harvests obtained from 49 cancer patients showed that the PBSC harvest contained precursors for antitumor effector cells. Ex vivo manipulation of these harvests to maximize the antitumor effector cell activity may provide a new therapeutic approach to decrease or eliminate any minimal residual disease that remains after high-dose therapy. Characterization of PBSC from consecutive collections determined the collections best suited for ex vivo augmentation of antitumor cytotoxic effector cells. We report the results of a functional and phenotypical characterization of PBSC obtained from six consecutive collections from 18 cancer patients receiving granulocyte-macrophage colony-stimulating factor (GM- CSF) for hematopoietic stem/progenitor cell mobilization. The PBSC were evaluated for their cytotoxicity using the 51Cr-release assay. The frequency and subsets of lymphocytes were determined using flow cytometry with appropriate specific marker antibodies and differential cell counts. The content of hematopoietic progenitor cells in each collection was determined using a colony-forming unit granulocyte- macrophage (CFU-GM) culture assay. The frequency of cytotoxic effector cells including lymphokine-activated killer (LAK) cell precursors and lymphocytes was significantly greater (P < .05) in the early collections, whereas the later collections contained significantly (P < .05) more CFU-GM progenitor cells and fewer cytotoxic effector cells. Thus, our results show that PBSC obtained from advanced cancer patients do contain considerable levels of precursor cells for the generation of LAK cell populations. These results suggest that cells from the earlier collections are best suited for ex vivo manipulation to augment the antitumor effects.  相似文献   
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Antibodies that bind prothrombin without neutralizing its coagulant activity were demonstrated in the plasma of two patients with the acquired hypoprothrombinemia-lupus anticoagulant syndrome. The first patient's plasma contained less than 1% prothrombin activity and no detectable prothrombin antigen. The second patient's plasma contained about 6% of both prothrombin activity and antigen. Neither patient's plasma neutralized the prothrombin coagulant activity of normal plasma or of purified prothrombin added in vitro. Nevertheless, double immunodiffusion studies and binding experiments utilizing 125I- prothrombin demonstrated the presence of prothrombin antibodies in each patient's plasma. A Scatchard analysis of the binding data obtained with different concentrations of 125I-prothrombin and the first patient's plasma indicated the presence of a high affinity antibody, apparent Kd approximately 10(-10)M, and a lower affinity antibody, apparent Kd approximately 10(-9)M. Studies utilizing purified cleavage products of prothrombin suggested that the antibodies were directed against an epitope or epitopes located on the carboxyl-terminal, latent thrombin segment of the prothrombin molecule. We postulate that the acquired hypoprothrombinemia in these two patients and in other reported patients with the acquired hypoprothrombinemia-lupus anticoagulant syndrome stems from rapid clearance from the circulation of prothrombin antigen-antibody complexes.  相似文献   
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Objective: The Adelaide Dental Study of Nursing Homes aimed to quantify oral disease experience, incidence and increments in Adelaide nursing home residents. Methods: Questionnaires and dental inspections were completed at baseline and at 1‐year for residents from randomly selected Adelaide nursing homes. Results: The residents were very functionally dependent, cognitively impaired and behaviourally difficult older adults with complex oral problems and dental treatment needs. The prevalence of edentulism (total tooth loss) (63%) decreased and more residents were retaining natural teeth. Existing residents had a mean of 10.8 teeth present and new residents had a mean of 12.7 teeth present. Residents’ previous experiences of caries (decay) were high – existing residents had a mean of 1.2 decayed teeth and new residents had a mean of 0.8 decayed teeth. Residents’ caries increments (new decay) over the 1‐year period were high (coronal = 2.5 surfaces; root = 1.0 surfaces), especially in those who had lost weight and who could eat fewer food types. These levels of caries were many times greater than had been reported for community‐dwelling older adults. Large accumulations of plaque, calculus and debris (food) were evident on residents’ natural teeth and dentures, especially those with dementia. Up to 25% of residents owned dentures that were not worn. Residents with dementia gave their carers complex and challenging oral hygiene care problems. Existing and new residents had similar general health and oral health characteristics, with the exceptions that new residents had significantly more filled tooth surfaces, and fewer decayed retained roots. Conclusion: New residents were being admitted to the nursing homes with a compromised oral health status or developed severe oral diseases and conditions within several months of their admittance. Residents’ oral diseases, especially coronal and root caries, rapidly progressed during their stay in residential care.  相似文献   
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