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91.
目的:为制备平痛新包衣微丸提供良好的底物,方法:以流动性指数为指标采用均匀设计优化平痛新素丸。结果:确定了制备平痛新素丸的最佳处方工艺。结论:淀粉量是影响产率的主要因素:转速是影响堆密度,脆碎度的主要因素;粘合剂用量是影响休止角和流动性的主要因素;滚动时间是影响喷流指数的主要因素。 相似文献
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New hepatitis B virus mutant form in a blood donor that is undetectable in several hepatitis B surface antigen screening assays 总被引:10,自引:0,他引:10
JM Jongerius ; M Wester ; HT Cuypers ; WR van Oostendorp; PN Lelie ; CL van der Poel; EF van Leeuwen 《Transfusion》1998,38(1):56-59
BACKGROUND: Envelope mutant forms of hepatitis B virus (HBV), impairing HBV antibody recognition, have been reported with mutations in single or multiple sites of the hepatitis B surface antigen (HBsAg) group- specific "a" determinant. Blood donors infected with such an HBsAg mutant form of HBV may escape detection by HBsAg screening assays and therefore may affect the safety of the blood supply. CASE REPORT: A repeat blood donor became HBsAg-reactive in an enzyme immunoassay. Confirmatory testing yielded negative results for HBsAg in a radioimmunoassay and in four enzyme immunoassays used in blood donor screening. The specificity of the HBsAg reactivity in the first enzyme immunoassay was confirmed by HBsAg neutralization with antibody to HBsAg. Additional HBV confirmatory test results were positive for antibody to hepatitis B core antigen and antibody to hepatitis B e antigen; negative for antibody to HBsAg and for hepatitis B e antigen; and positive for HBV DNA. DNA sequence analysis of the "a" determinant region of HBsAg revealed amino acid substitutions from Q (Gln) to R (Arg) at codon 129 and from M (Met) to T (Thr) at codon 133. CONCLUSION: This case illustrates the presence of HBsAg mutant forms of HBV in a West European blood donor population that were undetected by several HBsAg screening assays. Adaptation of HBsAg screening is indicated to overcome deficiencies in sensitivity in detecting HBsAg mutant forms of HBV. Screening for antibody to hepatitis B core antigen or HBV DNA may also detect blood donors infected with HBsAg mutant forms of HBV 相似文献
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A technique for quantitative analysis of growth plates in varus or valgus deformity about the knee has been developed. Computer-generated regions of interest are placed on magnification scintigraphs to divide distal femoral and proximal tibial physes into four equal segments. The ratio of counts in the medial half to counts in the lateral half was studied in 34 children (23 healthy, 11 with angular deformity). Normal ratios were 0.74-0.98 for femurs and 0.98-1.20 for tibias. An above-normal ratio correlated with the presence of valgus deformity and a below-normal ratio with varus deformity. This technique may provide a means of monitoring growth after trauma or infection. 相似文献
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Cystic adrenal lesions: CT features 总被引:8,自引:0,他引:8
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The accumulation of technetium-99m diethylenetriamine pentaacetic acid (Tc-99m DTPA) in benign soft-tissue neurofibromatosis tumors is reported. In a series of 16 patients with clinical stigmata of neurofibromatosis, 28 sites of abnormal soft-tissue localization of the isotope observed scintigraphically were documented to be sites of soft-tissue tumor by clinical and/or radiographic (predominantly computed tomographic) correlations. The smallest lesion detected was a 1.5-cm subcutaneous neurofibroma. Normal physiologic nonrenal distribution of the Tc-99m DTPA was established by scintigraphic imaging of a control population. 相似文献
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Powers TA; Partain CL; Kessler RM; Freeman MW; Robertson RH; Wyatt SH; Whelan HT 《Radiology》1988,169(3):723-726
Twenty pediatric patients, aged 2-18 years, with known or suspected masses in the brain and/or spinal cord were studied with magnetic resonance imaging at 0.6T with and without use of 0.1 mmol/kg gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA). The multisection, multiecho imaging mode was utilized. Surgically proved mass lesions included astrocytoma (n = 6), medulloblastoma (n = 2), ependymoma (n = 1), craniopharyngioma (n = 1), oligodendroglioma (n = 1), germinoma (n = 1) and fibrosarcoma (n = 1). Presumptive diagnoses included astrocytoma (n = 3), arachnoid cyst (n = 1), tuberous sclerosis (n = 1), cryptic vascular malformation (n = 1), and normal (n = 1). There was dramatic enhancement in 11 of 20 patients, with improved definition of the presence and extent of lesions in six patients. No adverse effects were noted in any of the 20 patients. It is concluded that Gd-DTPA is useful in delineating the presence, extent, and number of certain lesions of the central nervous system in children. 相似文献