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51.
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.  相似文献   
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We compared serum levels of total alkaline phosphatase (TAP) and bone-specific alkaline phosphatase (BAP) as determined by three different assays (lectin affinity electrophoresis, immunoradiometric assay, enzyme-linked immunosorbent assay) in subjects aged 5–20 years suffering from X-linked hypophosphatemic rickets ( n = 14), chronic renal failure ( n = 10) and chronic cholestatic liver disease ( n = 16). Results were compared to controls of the same age and were expressed as standard deviation scores (SDS). TAP correlated significantly with BAP ( r > 0.9 for each assay; p <0.001) in controls. In children with cholestatic diseases, TAP (median SDS + 2.0) was elevated, but BAP, as measured by the electrophoretic assay, was within the reference range for most patients (median SDS: -0.4; p = 0.003 for the difference between the median SDS of TAP and BAP). In contrast, results for BAP as determined by the two immunoassays were not significantly different from TAP in any of the three patient groups ( p > 0.05 in each group for both assays). In this study, the two immunoassays did not have a detectable advantage over lectin affinity electrophoresis in the determination of BAP.  相似文献   
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Fifty-two of 175 (30%) survivors of allogeneic marrow transplantation developed chronic graft-versus-hose diseases (GVHD). Five with limited chronic GVHD had an indolent clinical course with involvement of only the skin and liver. Forty-seven with extensive chronic GVHD had an unfavorable multiorgan disorder that resembled several autoimmune diseases. Thirteen patients with extensive disease (group I) were not treated and only 2 survive with Karnofsky scores >- 70%. Mortality resulted from infections and morbidity from sica syndrome, pulmonary and hepatic insufficiency, scleroderma-like skin disease, and contractures. Another 13 (group II) received a median of 8 mo prednisone and/or a brief course of antithymocyte globulin, and 3 survive without disability. The other 21 (group III) were treated with a combination of prednisone (1.0 mg/kg/q.o.d.) and either cyclophosphamide, procarbazine, or azathioprine (all 1.5 mg/kg/day) for a median of 13 mo. Combination therapy was well tolerated with only modest myelotoxicity. Fifteen in group III had a good and 4 a fair response to treatment while 2 with no response died. Azathioprine and prednisone was the most effective regimen. All therapy has been discontinued in 12 group III patients: GVHD returned in 5 (including 2 who died in spite of retreatment) while 7 remain free of GVHD for a median of 11 (range 6-30) mo observation. Only I group III survivor is disabled and 16 of the original 21 are alive 2-4 yr after transplant with Karnofsky scores of 70%-100%. Thus, combination immmunosuppression appears to favorably affect and, in some cases, premanently arrest the adverse natural course of extensive chronic GVHD.  相似文献   
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Eight patients with Fanconi's anemia were given cyclophosphamide alone (seven patients) or combined with procarbazine and antithymocyte globulin (one patient) followed by marrow grafts from HLA-identical siblings. All patients had engraftment. Seven developed acute and three chronic graft-versus-host disease (GVHD). Three patients died with GVHD and infectious complications (days 19, 56, and 82) and one with an intracerebral hemorrhage (day 540). Four patients are surviving 647- 3435 days after grafting, two are well, and two have chronic GVHD that is improving. These results show that Fanconi's anemia can be treated successfully by allogeneic marrow transplantation.  相似文献   
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Dai  CH; Krantz  SB; Zsebo  KM 《Blood》1991,78(10):2493-2497
To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation.  相似文献   
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