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Tumor markers are used to diagnose certain cancers and can be useful in monitoring the response to treatment. We describe a renal tumor with the features of a teratoid nephroblastoma associated with a raised serum level of alpha-fetoprotein (AFP). The serum AFP remained high during chemotherapy but returned to normal after nephrectomy. AFP was demonstrated by immunohistochemistry in cysts lined by enteric-type epithelium within the tumor. Cytogenetic examination of the tumor showed a clone of cells with trisomy 8. Raised serum AFP has not previously been described in teratoid Wilms' tumor.  相似文献   
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The efficacy of dicationic diarylfurans was evaluated against Cryptosporidium parvum by a suckling murine model. Candidate drugs were solubilized or suspended in deionized water and administered orally at a constant dose rate on days 0-5 (treatment day 0) to suckling ICR Swiss mice experimentally inoculated with oocysts of C. parvum. Efficacy was based on numbers of oocysts recovered from the intestinal tracts of mice subjected to necropsy examination on day 6. Numerous candidate furans significantly reduced the numbers of oocysts recovered from treated mice compared with control mice. Compounds 1, 2, 4, and 9 demonstrated superior efficacies (10% of controls or better) against C. parvum. Compounds 3, 5, 6, 7, 8, 11, 17, 18, and 19 also significantly reduced the numbers of oocysts recovered from treated mice but demonstrated efficacies ranging from 17 to 65% of controls. Compound 4 was particularly efficacious against C. parvum at a dosage as low as 8.5 mg/kg of body weight. Compound 4 is identified as a lead compound for additional studies in other animal models.  相似文献   
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Previous attempts at optimization of radiotherapy planning are described and criticized, and consideration of these attempts has resulted in the development of a new technique using quadratic programming. Uniformity of tumour dose is selected as the most important feature of any plan, and this is achieved by minimizing the variance of the dose to preselected points within the tumour. The dose to vulnerable regions can be constrained not to exceed a given percentage of the mean tumour dose. Optimization of field weight and field type is possible. The operation of the system is described and some typical results are given.  相似文献   
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Two hundred and forty-five knee dislocations were analyzed including forty-one new cases. The high incidence of injuries to the popliteal artery that accompanies this lesion (32 per cent) was confirmed, and it was re-emphasized that vascular repair must be completed within six or at the most eight hours from the time of injury to avoid amputation. Of the patients not treated within that time period, 86 per cent had an amputation and two-thirds of the remaining 14 per cent had ischemic changes.  相似文献   
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