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41.
Two children with acute lymphoblastic leukaemia (ALL) taking daily 6-mercaptopurine as part of a national UK therapeutic trial repeatedly developed profound myelosuppression on 25% of the standard protocol dose. Both were found to have undetectable intracellular activity of thiopurine methyltransferase (TPMT), an enzyme controlling one of the major alternative catabolic pathways of 6-mercaptopurine, and both produced higher concentrations of cytotoxic drug metabolites at 10-25% of the protocol dose than other patients taking 100%. It is supposed that these patients represent the 0.33% of the normal population constitutionally lacking TPMT. It is important to recognise such individuals both to avoid fatal bone marrow failure through inadvertent overdosage, and to be reassured that an adequate drug effect can be achieved at around 10% of the standard dose. 相似文献
42.
Multiple myeloma: evaluation by CT 总被引:3,自引:0,他引:3
Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs. 相似文献
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Tarsal navicular stress fractures: radiographic evaluation 总被引:3,自引:0,他引:3
Tarsal navicular stress fractures are a potential source of disabling foot pain in physically active individuals. The diagnosis of tarsal navicular stress fracture requires a high index of clinical and radiographic suspicion because the fracture is only rarely evident on routine radiographs or standard tomograms. The radiographic diagnosis of a tarsal navicular stress fracture may require anatomic anteroposterior tomograms or a radionuclide bone scan with plantar views. Radiographic examinations of 23 fractures in 21 patients are evaluated. 相似文献
46.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis. 相似文献
47.
Zhao P Qin ZL Ke JS Lu Y Liu M Pan W Zhao LJ Cao J Qi ZT 《第二军医大学学报》2005,26(10):1167-1167
SARS-CoV isa newly identified coronavirus that causes severe acute respiratory syndrome (SARS). Currently, there is no effective method available for prophylaxis and treatment of SARS-CoVinfections. In the present study, the influence of small interfering RNA (siRNA) on SARS-CoV nucleocapsid (N) protein expression was detected in cultured cells and mouse muscles. Four siRNA expression cassettes driven by mouse U6 promoter targeting SARS-CoV N gene were prepared, and their inhibitory effects on expression of N and enhanced green fluorescence protein (EGFP) fusion protein were observed. 相似文献
48.
0 引言 人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1 材料和方法1.1 DNA重组 人工合… 相似文献
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