低场强MRI对于颅内转移瘤诊断价值的分析

目的:评价探讨低场强磁共振检查在脑转移瘤中的诊断价值。方法:用0.3 T开放型磁共振成像系统对30例脑转移瘤患者的磁共振平扫、水抑制(FIR)和增强扫描-采用静脉快速推注顺磁性造影剂Gd-DTPA(0.2 ml/kg)结果进行分析。结果:30例中单发病灶8例,多发22例,平扫发现48个病灶,FIR发现72例,增强扫描发现96个病灶,65个病灶直径大于3 cm;发现最小病灶直径3 mm;伴发空洞54例。增强扫描发现平均每个病人有3.2个病灶。结论:MRI是脑转移瘤不可缺少的检查方法,低场强磁共振检查既可准确发现微小和特殊部位的转移灶,又可得到病灶的边缘形态和内部情况以便于治疗方案的确定。     

Mechanisms of white cell reduction in red cell concentrates by filtration: the effect of the cellular composition of the red cell concentrates

The effect of platelets on the removal of white cells (WBCs) from 16 to 24-hour-old red cell (RBC) concentrates by filtration was studied. RBC concentrates with various concentrations of platelets and WBCs were filtered on a cellulose acetate column filter and on three polyester flatbed filters. The microscopic study revealed that lymphocytes and most monocytes were captured in the smaller pores of the fiber network, irrespective of the brand of filter, the type of filter material, or the prefiltration platelet amount in the RBC concentrates. In contrast, efficient granulocyte depletion depended on granulocyte-platelet interaction and on the filter material. In the presence of platelets, granulocytes were captured in the top part of the column filter or in the coarse layers of two of the flatbed filters, where platelets covered the fibers. Platelet depletion of the RBC concentrates prior to filtration diminished the contribution of these parts of the filters to granulocyte capture. A larger part of the column filter or the fine layers of the flatbed filters were now required for granulocyte capture. In one of the flatbed filters, granulocyte-platelet interaction occurred mainly in the fine layers, which ended in blockage of this filter after the filtration of variable volumes (250-600 mL) of standard RBC concentrates. A quantitative estimation of the effect of platelets on the WBC-reduction capacity found that all three flatbed filters had a highly significant decrease (p = 0.001) in WBC-reduction capacity for platelet-depleted or buffy coat-depleted RBC concentrates, as compared with standard RBC concentrates.(ABSTRACT TRUNCATED AT 250 WORDS)     

Institutional variation in hemotherapy for solid organ transplantation

BACKGROUND: Solid organ allograft recipients may require large amounts of blood components. The modification of components to make them safer for iatrogenically immunosuppressed transplant patients increases workload demands on blood banks and transfusion services. STUDY DESIGN AND METHODS: Institutions within the United States and Canada providing hemotherapy as support for transplant recipients were surveyed for their transfusion practices. RESULTS: Responses from 25 institutions provide the data for this report. In 1991, the mean intraoperative red cell requirements ranged from <1 unit for renal allograft recipients to 17.3 units for liver transplant recipients. The latter group also required the greatest amounts of platelets, fresh-frozen plasma, and cryoprecipitate. More than 75 percent of responding institutions provided either cytomegalovirus-seronegative or white cell-reduced cellular components to pediatric recipients of liver allografts and to both adult and pediatric recipients of heart, lung, and heart-lung allografts. The use of irradiated cellular blood components, although uncommon, was greatest in heart transplant recipients. The use of pretransplantation transfusions for immunomodulation was generally limited to patients awaiting a living-donor renal transplant. CONCLUSION: Transfusion practices varied among the institutions, but the majority provide cytomegalovirus-safe cellular blood components to heart and lung allograft recipients and to pediatric transplant patients. Gamma-radiated cellular components are not routinely provided to patients undergoing solid organ transplantation. Liver allograft recipients require the greatest amount of hemotherapeutic support.     

CONGENITAL ABSENCE OF THE GALLBLADDER: WAYS OF AVOIDING LAPAROTOMY

SUMMARY Two cases of congenital absence (agenesis) of the gallbladder seen at one hospital over a 5-year period are presented. One patient presented with ascending cholangitis due to choledocholithiasis, while the other presented with right upper quadrant abdominal pain and equivocal findings on ultrasound and oral cholecystography. Although diagnosis was made at laparotomy in both cases, it is likely that the arrival of laparoscopic cholecystectomy will avoid laparotomy in the future. The place of laparoscopy in establishing the presence of this anomaly is discussed.