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991.
Guidelines for blood utilization review   总被引:11,自引:0,他引:11  
Hospitals are required by accrediting agencies to perform blood utilization review. Specific areas that must be addressed are the ordering, distribution, handling, dispensing, and administration of blood components. Monitoring the effects of transfusion on patients is also required. The format of the review process and the criteria for appropriate blood utilization must be developed by each institution. This article provides examples of areas that can be reviewed and procedures that may be used. However, the suggested laboratory values must not be interpreted as defining indications or criteria for transfusion. Each transfusion committee, or its equivalent, is responsible for developing its own institutional blood utilization procedures and audit criteria. Review and approval by the medical staff prior to implementation are essential. The procedures must also be reviewed and revised on a regular basis.  相似文献   
992.
Dale  GL; Friese  P; Hynes  LA; Burstein  SA 《Blood》1995,85(7):1822-1825
Approximately 6% of dog platelets are positive for staining with thiazole orange, a dye frequently used to stain ribonucleic acid. In this report, thiazole-orange positivity is shown to mark platelets that are less than 24 hours old. Dog platelets were derivatized in vivo with N-hydroxysuccinimido biotin such that greater than 95% of all platelets were biotinylated. Newly synthesized, nonbiotinylated platelets were then monitored by flow cytometry for their ability to bind thiazole orange. After biotinylation, the percentage of biotin-negative, thiazole-orange-positive platelets increased gradually from 0.72% at 30 minutes to 5.44% at 24 hours. These data indicate that thiazole-orange staining does label newly synthesized platelets.  相似文献   
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Differential expression of HLA-DR antigens in subsets of human CFU-GM   总被引:2,自引:0,他引:2  
Expression of HLA-DR surface antigens by granulocyte/monocyte colony- forming cells (CFU-GM) may be important in the regulation of proliferation of these cells. Using immunological techniques to enrich for progenitor cells, we investigated the expression of HLA-DR in subsets of CFU-GM. "Early" (day 14) CFU-GM express higher levels of HLA- DR than do "late" (day 7) CFU-GM. Among late CFU-GM, cells destined to form monocyte (alpha-naphthyl acetate esterase-positive) colonies express higher levels of HLA-DR than do CFU-GM destined to form granulocyte (chloroacetate esterase-positive) colonies. Because high- level expression of DR antigen was a marker for monocyte differentiation, we examined several lymphokines for their effects on both DR expression and in vitro commitment to monocyte differentiation by myeloid precursor cells. DR antigen density could be increased by more than twofold over 48 hours upon exposure to gamma-interferon (gamma-IFN), whereas colony-stimulating factors had no effect. This was associated with a dose-dependent inhibition of total CFU-GM number, and a relative, but not absolute, increase in the ratio of monocyte colonies to granulocyte colonies. Similarly, in day 7 suspension cultures of purified myeloid precursor cells, gamma-IFN inhibited cell proliferation and increased the ratio of monocytes to granulocytes. Thus, despite the induction of high levels of HLA-DR antigen on precursor cells (a marker of monocyte commitment), the dominant in vitro effect of gamma-IFN was inhibition of granulocyte differentiation.  相似文献   
995.
大鼠原位肝移植模型建立方法的若干问题探讨   总被引:2,自引:0,他引:2  
目的探讨建立大鼠原位肝移植模型的方法与技术。方法用改进的二袖套法行100例Lewis→BN大鼠原位肝移植,术中门静脉、肝下下腔静脉用袖套法吻合,肝上下腔静脉用缝合法吻合,胆管内支架法完成胆道重建。结果供体手术时间(30.9±5.0)min,供肝修整时间(10.0±3.0)min,受体手术时间(50.0±5.5)min,无肝期为(23.0±2.5)min。手术成功率为92%(术后存活2 d以上),1周存活率为87%,1个月存活率为84%。结论通过提高手术技巧,熟悉各种并发症的原因和预防处理措施,可以减少并发症的发生,提高手术成功率,延长大鼠术后存活时间。  相似文献   
996.
浙江省实验动物中心长爪沙鼠群体遗传状况分析   总被引:1,自引:0,他引:1  
目的 探讨浙江实验动物中心长爪沙鼠群体的遗传状况。方法 应用生化基因位点遗传检测方法,测定初始和生物净化长爪沙鼠群体27个生化位点等位基因的分布。结果 2个长爪沙鼠群体均具有丰富的遗传多样性;生物净化群体与初始群体比较有17.86%的基因丢失率,但尚未出现明显的遗传分化现象(FST〈0.05)。结论 群体均偏离了哈迪-温伯格平衡(P〈0.05)。  相似文献   
997.
OBJECTIVES: To determine the usefulness of electrocardiography (ECG) and chest radiography (CXR) in evaluation of patients referred to the pediatric cardiologist for the evaluation of heart murmur or chest pain. DESIGN: In this prospective study, 106 consecutive outpatients were categorized with no heart disease, possible heart disease, or definite heart disease based on history and physical examination; they then underwent ECG and CXR. Studies were reviewed and the examining cardiologist could change the diagnosis and order an echocardiogram. SETTING: Academic pediatric cardiology practice. RESULTS: In patients thought to have no heart disease, the diagnosis was changed to definite heart disease in four solely on the basis of abnormal CXR or ECG. In 25 patients thought to have possible heart disease, the diagnosis was changed to no heart disease (7) or definite heart disease (5) after review of the CXR and ECG. All 25 patients diagnosed with definite heart disease had this confirmed by abnormal CXR (2), ECG (3), both abnormal CXR and ECG, or echocardiogram (18). CONCLUSIONS: ECG and CXR helped diagnose heart disease in four patients thought to have no heart disease, helped to rule out lesions in seven patients with possible heart disease, helped diagnose heart disease in five patients thought to have possible heart disease, and helped confirm heart disease in nine patients. In these days of cost containment, routine ECG and CXR continue to be valuable tools for the pediatric cardiologist in evaluation of patients with heart murmurs or chest pain.  相似文献   
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