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A 71 year old man with chronic lymphocytic leukaemia (CLL) experienced excessive bleeding following transurethral resection of the prostate. Investigations showed a prolonged kaolin cephalin clotting time (KCCT) with low concentrations of factor XI. The prolonged KCCT was largely corrected by mixing with normal plasma but this correction was lost on incubation, confirming the presence of an inhibitor. He was treated with pulsed methylprednisolone and chlorambucil which resulted in the resolution of the bleeding problem and the loss of detectable circulating inhibitor.  相似文献   
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Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.  相似文献   
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报道了氯仿重结晶的棉酚的化学性质,样品在不同温度下干燥恒重后,经熔点、薄层层析、紫外光谱、红外光谱、X-射线衍射、热重量分析、元素(C,H,Cl)分析及棉酚合量测定等一系列的分析,确证了在60℃以下棉酚与氯仿成溶剂化物(solvate)。随着干燥温度的升高或在室温长时间的贮存,此现象逐渐消失,100℃真空干燥恒重后成为纯棉酚。  相似文献   
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Preparation for bone marrow transplantation (BMT) uses the extremely emetogenic combination of chemotherapy and total body irradiation (TBI). Ondansetron is a selective 5-HT3 antagonist and has clear anti-emetic capabilities. The efficacy of the drug was assessed in 15 children (aged 2-17 years) who received high dose cyclophosphamide (on days -6 and -5) and TBI (days -3 to 0 inclusive). During days -6 to -4 when the emetic effect of cyclophosphamide would be most pronounced, 12 of the 15 patients (80%) had fewer than five emetic episodes during their worst 24-h period, 11 (73%) had fewer than three vomits whilst nine (60%) experienced no vomiting or retching. Eleven patients progressed to TBI and 10 (91%) had fewer than five emetic events in the worst 24-h period (days -3 to +2), six (55%) had no vomiting at all. Of 100 evaluable 'patient-days' 83 (83%) were without any vomiting or retching and a further 10 'patient-days' had only one or two emetic episodes. There were no significant side-effects noted and in particular no extrapyramidal reactions. Headaches and constipation, which have been seen in adult studies, were not reported by patient or parent on any of the study days and transient elevation of liver enzymes were noted in only two patients. Ondansetron has a major role in preparing patients for BMT.  相似文献   
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Refractoriness occurs in a proportion of patients who receive multiple platelet transfusions. Alloantibodies, in particular those directed against the class I human leucocyte antigens (HLA) present on the platelet surface, are frequently associated with accelerated platelet destruction and transfusion failure. Compatible platelets for transfusion may be found by selecting donations from HLA-typed individuals, crossmatching patients' sera against donor lymphocytes and platelets or both. Maintaining a large panel of HLA-typed apheresis donors is expensive and some mismatching is inevitable due to the polymorphic nature of the HLA system. Cross-matching may improve the outcome when HLA-matched donations are transfused and may also be a cost-effective strategy for the selection of compatible untyped platelets. Administration of intravenous immunoglobulin, plasma exchange and ex vivo removal of platelet HLA have been employed successfully in a few refractory alloimmunized patients but do not yet have an established role. Experimental studies in animal models suggest that it may be possible to induce tolerance to HLA and prevent alloimmunization.  相似文献   
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A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties.  相似文献   
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