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91.
均衡组间差异的有效方法:倾向评分 总被引:4,自引:1,他引:3
目的:实例介绍倾向评分法的基本原理和适用条件,设计适用于分析二分类资料的SAS宏程序。方法:运用倾向评分比较平衡前后两组间差异的改变情况,评价放弃心肺复苏急救与充血性心力衰竭患者院内死亡的联系。结果:采用分层法和匹配法都可以有效地平衡两组各个特征变量间所存在的高度差异,三种分析方法获得相近的估计结果。结论:倾向评分法是均衡组间差异的有效方法,能够匹配和平衡各个特征变量的作用,并用于分析各种观察性研究资料。 相似文献
92.
CT影像学评分预测急性胰腺炎病情及转归的研究 总被引:2,自引:0,他引:2
目的 探讨CT影像学评分对急性胰腺炎病情和转归的预测价值。方法 回顾性分析入院后经CT检查的急性胰腺炎46例,按一定的规则对每例患进行CT影像学评分与分型,并与临床治疗中的有关资料进行对照。结果 46例患CT评分后获得:轻型24例,中型13例,重型9例。轻型患较重型住院日少、恢复顺利,中转手术及死亡率均以重型为高。结论 CT评分对急性胰腺炎病情及预后评估具有重要意义。 相似文献
93.
Rashmi Kothari MD Kent Hall MD Thomas Brott MD Joseph Broderick MD 《Academic emergency medicine》1997,4(10):986-990
Objective : To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke.
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke.
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed. 相似文献
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed. 相似文献
94.
95.
Bruce Becker MD Robert Woolard MD Ted D. Nirenberg PhD P. Allison Minugh PhD Richard Longabaugh EdD Patrick R. Clifford PhD 《Academic emergency medicine》1995,2(9):784-790
Objectives: To determine the incidence of alcohol use in subcritically injured patients presenting to the ED, by using a saliva alcohol test (SAT) at ED triage during the ED initial assessment; to compare the incidence of alcohol use revealed by the SAT with documentation of alcohol use by ED nurses and emergency physicians (EPs) blinded to the SAT results; and to describe the demographics of the SAT-positive, subcritically injured population.
Methods: A blinded, prospective, observational evaluation of ED patients presenting with subcritical injuries was performed. The patients were tested for alcohol use with an SAT, and a subsequent record review was conducted for extraction of demographic data and evidence of documentation of alcohol use by ED nurses and EPs blinded to the SAT results.
Results: During the study. 791 subcritically injured patients had SATs performed. Twenty-one percent of these patients were found to be alcohol-positive by SAT. Either the ED nurse or the EP documented a clinical impression of alcohol use for 52% of the SAT-positive patients. There were higher SAT-positive rates among men (24%), victims of assault (47%), and patients arriving at night (41%).
Conclusions: While the SAT identified 21% of the subcritically injured patient population as alcohol-positive, ED nurse and EP documentation did not identify half of these alcohol-positive patients. Many of these patients may be at risk for additional injuries related to their drinking behavior. 相似文献
Methods: A blinded, prospective, observational evaluation of ED patients presenting with subcritical injuries was performed. The patients were tested for alcohol use with an SAT, and a subsequent record review was conducted for extraction of demographic data and evidence of documentation of alcohol use by ED nurses and EPs blinded to the SAT results.
Results: During the study. 791 subcritically injured patients had SATs performed. Twenty-one percent of these patients were found to be alcohol-positive by SAT. Either the ED nurse or the EP documented a clinical impression of alcohol use for 52% of the SAT-positive patients. There were higher SAT-positive rates among men (24%), victims of assault (47%), and patients arriving at night (41%).
Conclusions: While the SAT identified 21% of the subcritically injured patient population as alcohol-positive, ED nurse and EP documentation did not identify half of these alcohol-positive patients. Many of these patients may be at risk for additional injuries related to their drinking behavior. 相似文献
96.
Restless legs syndrome (RLS) is a disorder of motor activity with a circadian pattern, occurring frequently in patients with Parkinson's disease (PD). We sought to estimate the prevalence of RLS in Indian PD patients. One hundred twenty-six consecutive PD patients and 128 healthy age- and sex-matched controls were evaluated using a predesigned questionnaire. RLS was present in 10 of 126 cases of PD (7.9%) and 1 of 128 controls (0.8%, P = 0.01). PD patients with RLS were older than those without RLS (63.70 +/- 7.80 years vs. 57.37 +/- 10.04 years; P = 0.05) and had higher prevalence of depression (40% vs. 10.3%; P = 0.023). No demographic factors or factors related to PD correlated with the presence or severity of RLS. RLS is more common among patients with PD than controls. A greater medical recognition of this disorder is needed in view of available effective treatment. 相似文献
97.
以髓系(HL-60)与淋系(Molt-4)细胞为观察对象,用细胞计数、细胞集落培养、台酚蓝拒染及溴化二甲噻唑二苯四唑试验为观察手段,研究胎肌条件培养液(FMCM)对白血病细胞的影响.实验标本分为4组:①对照组.②20%FMCM处理组.③阿糖胞苷(Ara-C,1×10~(-7)M/L)处理组.④混合处理组(经FMCM与Ara-C二者的处理).发现:①FMCM对两个细胞株均无明显的直接作用.②当HL-60细胞经FMCM预处理或在用Ara-C处理同时加入FMCM,Ara-C对其抑制作用可为FMCM加强,已受Ara-C抑制的HL-60细胞则无此现象.③Ara-C对Molt-4的抑制作用不受FMCM的影响.由此而初步认为:①FMCM对白血病细胞似无明显直接作用.②某些(非全部)白血病细胞对Ara-C的敏感性可为FMCM加强.③在己受抑制的细胞中不呈现这种致敏现象.①提示FMCM有可能用于白血病临床治疗. 相似文献
98.
用动物肠道溶瘤病毒(Ecco-18)实验治疗荷瘤小鼠(P_(615))时,对其非瘤器官进行了光镜和电镜观察。结果发现,荷瘤小鼠各脏器均未查到病毒颗粒或病毒性物质。各脏器的超微结构与对照组相比未见病理改变。 相似文献
99.
胎肌条件培养液(FMCM)可在CFU-GM体外培养中提供集落刺激活性。研究发现它还能在体外培养中保护CFU-GM,减轻理化损伤因素对其生长的抑制效应。所用化学损伤因素为5×10-7M的阿糖胞苷与9×10-9M的三尖杉酯碱,物理损伤因素为放射(3.5Gy),热(44℃,60分钟)与冷(—20℃,16分钟)。在损伤因素作用下,CFU-GM的集落产率受到明显抑制,用20%FMCM处理后,抑制现象可以减轻。FMCM可以对抗多种因素对CFU-GM的抑制作用,没有特异性。用胰蛋白酶或热(85℃,30分钟)处理后的FMCM不具上述保护效应,用酸(PH=2),碱(PH=10),DNA酶与透析处理则无明显影响。提示FMCM中起保护作用的活性物质可能为分子量大于10000的蛋白质。 相似文献
100.
Abdulmassih S. Iskandrian Jeffrey Johnson Tung T. Le Valerie Wasserleben Virginia Cave Jaekyeong Heo 《Journal of nuclear cardiology》1994,1(2):144-149