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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   
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993.
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   
994.
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   
995.
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   
996.
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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999.
We have generated mouse models of human Tay-Sachs and Sandhoff diseases by targeted disruption of the Hexa (alpha subunit) or Hexb (beta subunit) genes, respectively, encoding lysosomal beta-hexosaminidase A (structure, alpha) and B (structure, beta beta). Both mutant mice accumulate GM2 ganglioside in brain, much more so in Hexb -/- mice, and the latter also accumulate glycolipid GA2. Hexa -/- mice suffer no obvious behavioral or neurological deficit, while Hexb -/- mice develop a fatal neurodegenerative disease, with spasticity, muscle weakness, rigidity, tremor and ataxia. The Hexb -/- but not the Hexa -/- mice have massive depletion of spinal cord axons as an apparent consequence of neuronal storage of GM2. We propose that Hexa -/- mice escape disease through partial catabolism of accumulated GM2 via GA2 (asialo- GM2) through the combined action of sialidase and beta-hexosaminidase B.   相似文献   
1000.

Background

Overweight and obesity in Australia has risen at an alarming rate over the last 20 years as in other industrialised countries around the world, yet the policy response, locally and globally, has been limited. Using a childhood obesity summit held in Australia in 2002 as a case study, this paper examines how evidence was used in setting the agenda, influencing the Summit debate and shaping the policy responses which emerged. The study used multiple methods of data collection including documentary analysis, key informant interviews, a focus group discussion and media analysis. The resulting data were content analysed to examine the types of evidence used in the Summit and how the state of the evidence base contributed to policy-making.

Results

Empirical research evidence concerning the magnitude of the problem was widely reported and largely uncontested in the media and in the Summit debates. In contrast, the evidence base for action was mostly opinion and ideas as empirical data was lacking. Opinions and ideas were generally found to be an acceptable basis for agreeing policy action coupled with thorough evaluation. However, the analysis revealed that the evidence was fiercely contested around food advertising to children and action agreed was therefore limited.

Conclusion

The Summit demonstrated that policy action will move forward in the absence of strong research evidence. Where powerful and competing groups contest possible policy options, however, the evidence base required for action needs to be substantial. As with tobacco control, obesity control efforts are likely to face ongoing challenges around the nature of the evidence and interventions proposed to tackle the problem. Overcoming the challenges in controlling obesity will be more likely if researchers and public health advocates enhance their understanding of the policy process, including the role different types of evidence can play in influencing public debate and policy decisions, the interests and tactics of the different stakeholders involved and the part that can be played by time-limited yet high profile events such as Summits.
  相似文献   
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