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11.
Objectives: This study examines the efficacy of the predicting power for hospital mortality and functional outcome of three different scoring systems for head injury in a neurosurgical intensive care unit (NICU). Design: On the day of admission, data were collected from each patient to compute the Acute Physiology, Age, and Chronic Health Evaluation (APACHE) II and III, and Glasgow Coma Scale (GCS) scores. Hospital mortality was defined as the deaths of patients before discharge from hospital. Early mortality was defined as death before the 14th day after admission. Late mortality was defined as death after the 15th day from admission. Functional outcome was evaluated by Index of Independence in Activities of Daily Living (Index of ADL). Setting: An 8-bed NICU in a 1270-bed medical center in Taichung Veterans General Hospital. Patients and participants: Two hundred non-selected patients with acute head injury were included in our study in a consecutive period of 2 years. Patients less than 14 years old were not included. Interventions: None. Measurements and results: Sensitivity, specificity and correct prediction outcome were measured by the chi-square method in three scoring systems. The Youden index was also obtained. The best cut-off point in each scoring system was determined by the Youden index. The difference in Youden index was calculated by Z score. A difference was also considered if the probability value was less than 0.05. The area under Receiver Operating Characteristic (ROC) curve was computed. Then the area under ROC of each scoring system was compared by Z score. There was statistical significance if p was less than 0.05. For prediction of hospital mortality, the best cut-off points are 55 for APACHE III, 17 for APACHE II and 5 for GCS. The correct prediction outcome is 82.4% in APACHE III, 78.4% in APACHE II and 81.9% in the GCS. The Youden index has best cut-off points at 0.68 for APACHE III, 0.59 for APACHE II, and 0.56 for GCS. The area under Receiver Operating Characteristic (ROC) curve is 0.90 in the APACHE III, 0.84 in the APACHE II and 0.86 in the GCS. There are no statistical differences among APACHE III and II, and GCS in terms of correct prediction outcome, Youden Index and the area under the ROC curve. Other physiological variables excluding GCS in APACHE III and II (AP III-GCS, AP II-GCS) have less statistical value in the determination of mortality for acute head injury. For the prediction of late mortality, APACHE III and II yield significantly better results in the area under the ROC curve, correct prediction and Youden index than those of GCS. Other physiological variables (AP III-GCS and AP II-GCS) play an important role in the prediction of late mortality in APACHE scores. For prediction of the functional outcome of surviving patients with acute head injury, the APACHE III yields the best results of correct prediction outcome, Youden index and the area under the ROC curve. Conclusion: The APACHE III and II may not replace the role of GCS in cases of acute head injury for hospital or early mortality assessment. But for prediction of the late mortality, the APACHE III and II have better accuracy than GCS. Other physiological variables excluding GCS in the APACHE system play a crucial contribution for late mortality. GCS is simple, less time-consuming and economical for patients with acute head injury for the prediction of hospital and early mortality. The APACHE III provides better prediction for severe morbidity than GCS and APACHE II. Therefore, the APACHE III provides a good assessment not only for hospital and late mortality, but also for functional outcome. Received: 22 May 1995 Accepted: 2 September 1996  相似文献   
12.
Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level.The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring.The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure.  相似文献   
13.
Ritschl  P.  Karnel  F.  Hajek  P. 《Skeletal radiology》1988,17(1):8-15
The radiomorphological appearance of fibrous metaphyseal defects (FMDs) is demonstrated by long-term follow-up studies. A characteristic radiomorphological course rather than a typical single appearance can be established. These findings correlate well with the duration of these tumor-like lesions; therefore, the radiological findings allow conclusions to be made about the age of a fibrous metaphyseal defect. In addition, the characteristic locations of FMDs will be explained in respect of their origins at insertions of tendons and ligaments.  相似文献   
14.
The enhancement of fluorescence emission from the tryptophan residue of glucagon, the quenching of that emission with acrylamide and with 5-doxyl and 16-doxyl stearic acid, circular dichroism spectra, the release of 6-carboxytluorescein, and polarized infrared attenuated total reflection (IR-ATR) spectra were used to study the interaction of glucagon with intact lipid vesicles and flat bilayers. Dimyristoylphosphatidylcholine bound the peptide only below the main transition temperature, thus confirming earlier results of Epand et al. (1977). However, the peptide is also bound by vesicles of unsaturated lipids above their transition temperature, suggesting an influence of lipid area on the binding process. Circular dichroism showed that binding to such vesicles also increases the helix content of glucagon. The IR-ATR study and a comparison with dynorphin-A-(I-13)-tridecapeptide revealed profound differences in orientation of the two peptides. The dichroic ratios and the derived order parameters indicated an isotropic orientation of the helical segments of glucagon, but did not exclude a principal orientation of the molecules lying flat on the nienibrane surface. In contrast, the axis of the dynorphin helix is clearly oriented normal to the interface. The two peptides also differ in their rates of 6-carboxyfluorescein release, suggesting a deeper penetration of the primary amphiphilic helix of dynorphin A-(I-13) than of the secondary amphiphilic helix of glucagon.  相似文献   
15.
Synaptosomal Na, K-ATPase during forebrain ischemia in Mongolian gerbils   总被引:1,自引:0,他引:1  
We studied the activity and kinetic parameters of synaptosomal Na, K-ATPase during 15 min of forebrain ischemia and following 60 min of reperfusion produced by reversible common carotid occlusion in Mongolian gerbils. A synaptosomal fraction was obtained by both differential centrifugation of brain tissue homogenate and centrifugation of crude mitochondrial fraction at a discontinual sucrose density gradient. We found two components of ATP concentration dependence of ATP hydrolysis that represent two types of ATP-binding sites: high affinity and low affinity. Neither ischemia nor reperfusion affected kinetic parameters of a high-affinity site. However, lowaffinity site parameters were affected by both ischemia and ischemia followed by reperfusion. Maximal velocity (V max) decreased by 43 and 42% after ischemia and after ischemia/reperfusion, respectively. The apparentK m for ATP decreased by 52% after ischemia and by 47% after ischemia/reperfusion. The apparent affinities for K+ and Na+ were determined from the ATP hydrolysis rate as a function of Na+ and K+ concentrations. We found the half-maximal activation constant for K+ (K a K+) increased by 60% after ischemia and by 146% after ischemia/reperfusion. On the other hand, we found thatK aNa+ decreased significantly after ischemia/reperfusion (16%). We concluded that it is the dephosphorylation step of the ATPase reation cycle that is primarily affected by both ischemia and ischemia/reperfusion. This might be caused by alteration of the protein molecule and/or its surroundings subsequent to ischemia.  相似文献   
16.
陈书盘  耿沁 《肿瘤》1997,17(5):258-261
目的评价检测CYFRA21┐1对非小细胞肺癌的诊断价值。方法用ELISA法测定70例肺癌(LC)其中47例非小细胞肺癌(NSCLC),3例小细胞肺癌(SCLC)和20例未分型肺癌、64例肺部良性疾病患者及40例健康人血清CYFRA21┐1浓度。试验的诊断性能用相对操作特征(ROC)分析法估测之。结果测得全阈诊断准确率(OveralDiag┐nosticAccuracies)LC为0.75、NSCLC为0.76,SQC为0.83,ADE为0.67和SCLC为0.38。在相应于特异性为0.95的界定值3.47μg/L处,各型的灵敏度分别为SQC0.62,LC0.53,NSCLC0.51,ADE0.48和SCLC0.00。结论结果显示CYFRA21┐1是NSCLC较灵敏和特异的一个标志物。未观察到TNM各期间该标志物的平均水平有明显的差异;然而异常升高水平的患者的比例随病期的进展而显著增加,提示一系列检测CYFRA21┐1水平可能有助于监查NSCLC患者的疗效。  相似文献   
17.
本文讨论了激光脉冲射线强化金属材料的几个问题:强化图形,材料性能,加工用量及表面涂层对被强化表面性能的影响。  相似文献   
18.
在实验室绝热反应器中进行了乙苯脱氢制苯乙烯的反应动力学研究。根据不同反应机理,提出五种反应模型,经残差分析及模拟计算规律与实验规律的比较,确定Carra双曲模型为最佳反应动力学模型。通过对实验数据的回归拟合,经参数估计求得了速率方程的频率因子和活化能。  相似文献   
19.
Abstract The purpose of this study was to determine the clinical response to local delivery of tetracycline in relation to clinical and microbiological conditions of the other teeth. 4 deep pockets were monitored in 19 subjects with multiple deep periodontal lesions and high counts of P. gingivalis. In 9 patients (XT) only 2 of the selected lesions were treated by placement of tetracycline fibers (Actisite®). while the rest of the dentition was left untreated. In the other 10 patients, all teeth were supragingivally scaled and then treated by application of polymeric tetracycline HCl containing fibers, the whole dentition was subject to full mouth scaling and root planing, and the patients rinsed with 0.2% chlorhexidine (FT). A significant reduction in mean PPD was observed in all treated sites after two months. This reduction was maintained over the following 4 months. The magnitude of the effect was significantly greater in the FT group (1.74 mm) than in the LT group (0.88 mm). The mean attachment level changes were similar after 2 months in locally and fully treated subjects. A tendency of relapse was noted for treated sites in LT patients from month 2 to 6. A level of statistical significance was not reached for this effect. Data from measurements recorded at 6 sites around all teeth in the full mouth treated patients were analyzed using multiple linear regression. This analysis showed local changes in PPD and AL were significantly and strongly correlated with the baseline value of the respective parameter at the same site. In addition, more pocket depth reduction was noted if a site was not bleeding on probing at 6 months, if the location of a site was not approximal and if the tooth was not a second molar. Sites located on second molars showed also less AL gain than sites located on other teeth. Smokers showed significantly less reduction in PPD and significantly less AL gain. Furthermore, if subjects had a high % of pockets deeper than 4 mm at baseline they showed significantly less attachment gain.  相似文献   
20.
Blood gas analysis can be used to reliably predict outcome in infants with congenital diaphragmatic hernia (CDH) both before and after surgical repair, providing these values are indexed to some measurement of alveolar ventilation. Until recently there has been difficulty in interpreting some of the published data because of differing sampling sites and the fact that ventilatory parameters, which have major influences on all blood gas values in this anomaly, were not included. Application of this information enables us to identify infants with similar degrees of severity of CDH in order to evaluate the efficacy of novel forms of therapy and to determine whether they represent a genuine advance in management where more conventional forms of treatment have failed.  相似文献   
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