富氧对缺氧大鼠心肌琥珀酸脱氢酶及超微结构的影响

目的：探讨富氧对缺氧大鼠心肌损伤的保护作用及机理。方法：雄性Wistar大鼠32只随机分为平原对照组、低氧组、富氧组，低氧组在模拟海拔5400m低压舱内24h，富氧组在模拟5400m的低压舱内12h，然后富氧（27．0％的氧混合气）12h，观察心肌琥珀酸脱氢酶（SDH）及超微结构的改变。结果：低氧组心肌细胞灶性变性坏死，肌丝溶解凝固，间质水肿液和纤维素样渗出。富氧组心肌无明显病变，仅滑面内质网轻度扩张。富氧组SDH活性明显高于低氧组。结论：低氧导致心肌SDH活性及超微结构的改变，富氧对心肌有保护作用。     

Expert system-controlled image display

Conventional computer-based medical expert systems deliver advice to physicians as written text. While such advice is useful, it has distinct limitations in a visually oriented discipline such as diagnostic radiology, in which decisions often depend on pattern recognition and appreciation of subtle morphologic features. The authors developed a prototype expert computer system, IMAGE/ICON, which displays groups of images sorted into a series of axes based on different ways in which they may be similar. They may share a common feature, group of features, causes, or clinical setting. IMAGE/ICON may display examples of morphologic variations of a dominant finding or a spectrum of abnormalities seen in an specific disease or group of diseases. The system also assembles a written analysis of key features of a case. Such a tool may be useful as a diagnostic aid or for continuing medical education. It is likely to have particular impact in the form of an intelligent radiologic workstation, as picture archiving and communication systems become available.     

Prediction of bacterial meningitis in children with meningeal signs: reduction of lumbar punctures

Physicians often have to perform a lumbar puncture to ascertain the diagnosis in patients with meningeal signs, because of the serious consequences of missing bacterial meningitis The aim of this study was to derive and validate a clinical rule to predict bacterial meningitis in children with meningeal signs, to guide decisions on the performance of lumbar punctures. Information was collected from records of patients (aged 1 mo to 15 y) consulting the emergency department of the Sophia Children's Hospital between 1988 and 1998 with meningeal signs. Bacterial meningitis was defined as cerebrospinal fluid (CSF) leucocyte count >5 cells μl^?1 with a positive bacterial culture of CSF or blood. The diagnostic value of predictors was judged using multivariate logistic modelling and area under the receiver operating characteristic curves (ROC area). In the derivation set (286 patients, years 1988–1995) the duration of the main complaint, vomiting, meningeal irritation, cyanosis, petechiae and disturbed consciousness were independent clinical predictors of bacterial meningitis. The ROC area of this model was 0.92. The only independent predictor from subsequent laboratory tests was the serum C‐reactive protein concentration, increasing the ROC area to 0.95. Without missing a single case, this final model identified 99 patients (35%) without bacterial meningitis. Validation on 74 consecutive patients in 3 subsequent years (1996–1998) yielded similar results. Conclusion: This prediction rule identifies about 35% of the patients with meningeal signs in whom a lumbar puncture can be withheld without missing a single case of bacterial meningitis. For the individual patient this prediction rule is valuable in deciding whether or not to perform a lumbar puncture.     

胫骨下端恶性骨肿瘤切除后大段异体骨重建

目的应用大段异体骨移植及踝关节融合的保肢方法治疗胫骨下端恶性肿瘤和侵袭性肿瘤，并从预后、术后并发症及功能等几个方面加以评价。方法自1998年1月至2005年12月应用大段异体骨移植及踝关节融合的保肢方法治疗胫骨下端肿瘤患者11例；包括骨肉瘤8例，骨巨细胞瘤2例，软骨肉瘤1例。对骨肉瘤患者行新辅助化疗，按照Enneking分期，手术行边缘切除或广泛切除，应用大段深低温冷冻保存同种异体骨重建，钢板螺钉或带锁髓内钉固定。结果术后随访18-78个月，平均47个月。其中8例骨肉瘤患者随访28-78个月，平均50个月。11例均获得良好的骨愈合，开始出现骨愈合时间为术后3-18个月，平均8个月。无异体骨反应继发感染，无内固定失败。异体骨骨折1例，复发2例，肺转移3例，保肢率为81．8％。术后功能评定采用骨骼肌肉系统肿瘤手术治疗后重建功能评估系统（MSTS系统），评分为16～27分，平均24-3分。结论胫骨下端虽然软组织覆盖较薄，血运相对较差，但保肢术后肿瘤复发率不高，异体骨感染、不愈合、骨折率较低。固定方式以髓内固定为佳。大段异体骨移植及踝关节融合的保肢方法术后功能良好，给患者带来较大的心理安慰，是一种较好的保肢方式。     

Bile duct obstruction: radiologic evaluation of level, cause, and tumor resectability

In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.     

Evaluation of pediatric transfusion practice using criteria maps

Pediatric blood transfusion practice in a tertiary-care pediatric hospital was evaluated retrospectively by using the technique of criteria mapping. A total of 630 transfusion episodes involving red cell concentrates, frozen plasma (plasma frozen within 24 hours of collection), platelet concentrates, and albumin were reviewed: 243 (86.2%) were reviewed only by a technical assistant, and 87 (13.8%) required additional physician review. Of these, 138 were red cell concentrate transfusions: 79.7 percent of that group were considered appropriate, 11.6 percent of unknown benefit/risk ratio, 5.8 percent inappropriate, and 2.9 percent impossible to evaluate. Some 246 frozen plasma transfusions were reviewed: 42.3 percent were considered appropriate, 32.5 percent of unknown benefit/risk ratio, 17.5 percent inappropriate, and 7.7 percent impossible to evaluate. A total of 139 platelet concentrate transfusions were reviewed: 64.7 percent were considered appropriate, 16.5 percent of unknown benefit/risk ratio, 10.1 percent inappropriate, and 8.6 percent impossible to evaluate. Some 107 albumin transfusions were reviewed: 90.6 percent were considered appropriate, 1.9 percent inappropriate, and 7.5 percent impossible to evaluate. The criteria maps developed for this study were easy for the technical assistant to use, and areas of appropriate and inappropriate pediatric transfusion practice were clearly identified.     

营养支持在急性重症胰腺炎患者中的应用及护理

目的探讨对急性重症胰腺炎（ASP）患者施行肠内肠外阶段性营养支持的效果。方法回顾性分析121例实施营养支持的ASP患者资料,包括观察患者营养支持时间、体质量变化、血清清蛋白、住院天数与营养支持有关的并发症。结果2例死于多器官功能衰竭,死亡率1.7%。其余119例行营养支持治疗,营养支持时间（25.6±5.1）d,其中83例体质量增加,38例体质量无明显变化;97例血清清蛋白提高,24例无明显变化。119例ASP患者均逐渐达到正氮平衡,并痊愈出院,平均住院时间为（31.5±17.1）d。发生与营养支持有关的并发症12例,其中消化不良9例,高渗性利尿3例,均治愈。结论在ASP患者营养支持的治疗和护理中,做好营养支持工作是治愈ASP的重要措施。     

电磁脉冲辐射对原癌基因c-fos调控区的影响

目的　通过研究电磁脉冲 (electromagneticpulse ,EMP)辐射对原癌基因c fos调控区域的影响 ,探讨其诱导细胞功能改变的机制。方法　构建c fos启动区氯霉素乙酰化转移酶 (chloramphenicolacetyl transferase,CAT) ,然后转染HeLa癌细胞株 ,高场强EMP模拟源 (有界波模拟源 )辐射细胞 ,EMP场强为6× 10 4V/m ,脉冲上升时间为 2 0ns ,脉宽为 3 0 μs ,频率为 2 .5个脉冲 /min ,辐射 2min ,处理后 2 0min时观察细胞中CAT的活性。结果　EMP辐射转染的细胞后 2 0min ,转染了P50 0 ( -711～ -2 2 3bp)和P2 50 ( -3 62～-10 0 )的Hela细胞其CAT活性明显高于对照水平的活性 (P <0 .0 1)。结论　EMP辐射可引起c fos基因调控区的 -3 62～ -2 2 5明显改变。     

Discrepancies in reverse ABO typing due to prozone

Three group O sera manifesting prozone in reverse ABO tests are reported. All were implicated in erroneous blood typing results. One sample failed to react with A1 red cells (RBCs) in immediate-spin (IS) tests, had anti-A and -B titers of 8192 and 2048, respectively, by indirect antiglobulin technique (IAT), and was from a diabetic patient; the parenteral administration of A substance present in porcine insulin is a possible cause of hyperimmunity in this case. The second sample was from the recipient of a single unit of group B fresh-frozen plasma; the serum anti-A and -B titers were 10,240 by IAT, but only weak reactions with A1 and B RBCs were noted in routine IS reverse typing tests; the hyperimmunity in the patient concerned was likely due to crossreacting anti-A, B stimulated by B-active glycoproteins and/or glycolipids in the transfused plasma. The third serum also had anti-A and anti-B IAT titers of 10,240 but did not react with A1 and B RBCs by IS; the hyperimmunity in this case may be related to sepsis from intestinal flora carrying A- and/or B-like antigens. These antibodies lysed A1 and/or B RBCs in tests incubated at room temperature (RT) and strongly agglutinated those RBCs by IS when diluted 10-fold with saline. The absence of the prozone phenomenon in tests with RBCs suspended in diluents containing EDTA is consistent with the previously published mechanism for anti-A prozone: namely, the steric hindrance of agglutination by the C1 component of human complement.(ABSTRACT TRUNCATED AT 250 WORDS)     

Electronic verification of donor-recipient compatibility: the computer crossmatch

Background: This article describes standard operating procedures (SOPs) for a computer crossmatch to replace the immediate-spin crossmatch for ABO incompatibility between patient blood samples submitted for pretransfusion testing and the blood component selected for transfusion. These SOPs were developed following recent changes to the Standards for Blood Banks and Transfusion Services of the American Association of Blood Banks (AABB). Study Design and Methods: SOPs were developed, utilizing currently available software, for pretransfusion testing. The SOP for donor unit processing entails bar code entry of the unit number, component name, and ABO/Rh type; computer entry and interpretation of serologic reactions; warning of discrepancies between bar code-entered blood type and result interpretation; and quarantine of the donor unit in such instances. The SOP for patient sample testing requires bar code entry of specimen accession number, which accesses patient demographics; computer entry and interpretation of ABO/Rh tests; repeat blood typing at the time of crossmatch if only one patient blood type is on record; and warning if there are nonconcordant current and historical blood types. The computer crossmatch SOP requires bar code entry of specimen accession and donor unit numbers; release of group O red cells pending resolution of discrepancies; and immediate-spin crossmatch during computer downtime. Tables validated on- site prompt warning messages and prevent both computer crossmatch and release if blood components of the wrong ABO type are selected. Results: These SOPs meet the requirements of the 15th edition of the AABB Standards. Projected annual time savings at this institution are > 100,000 workload recording units. Further benefits include reduced patient sample volume requirements, less handling of biohazardous material, and elimination of unwanted positive or negative reactions associated with the immediate-spin crossmatch. Release of incompatible blood components when the wrong patient blood type is on record is addressed by requiring the use of group O red cells in the absence of two concordant blood types, one of which must be from a current sample. Conclusion: A combination of existing computer programs and carefully developed SOPs can provide a safe and efficient means of detecting donor-recipient incompatibility without performance of serologic crossmatch.