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991.
Abdou Elhendy Marcel L. Geleijnse Ron T. van Domburg Jeroen J. Bax Peter R. Nierop Suzan A. M. Beerens Roelf Valkema Eric P. Krenning M. Mohsen Ibrahim Jos R. T. C. Roelandt 《European journal of nuclear medicine and molecular imaging》1997,25(1):69-78
Stress echocardiography has been considered an accurate method for the diagnosis of coronary artery disease in hypertensive
patients and in patients with left ventricular hypertrophy. In contrast, the specificity of myocardial perfusion scintigraphy
in these patients has been questioned. The aim of this study was to compare the accuracy of these two imaging modalities in
conjunction with dobutamine stress test for the diagnosis of coronary artery disease in hypertensive patients with and without
left ventricular hypertrophy. Dobutamine (up to 40 μg kg–1min–1) stress echocardiography in conjunction with sestamibi (MIBI) single-photon emission tomography (SPET) was performed in 84
patients with the diagnosis of systemic hypertension who had been referred for evaluation of myocardial ischaemia. Ischaemia
was defined as new or worsened wall motion abnormalities at echocardiography and reversible perfusion defects at SPET. Significant
coronary artery disease (≥50% luminal diameter stenosis) was detected in 66 patients (79%). The sensitivity, specificity and
accuracy of the ischaemic pattern at echocardiography for the diagnosis of coronary artery disease were 73% (CI 63%–82%),
83% (CI 75%–91%) and 75% (CI 66%–84%), those for MIBI were 67% (CI 57%–77%), 83% (CI 75%–91%) and 70% (CI 60%–80%) respectively
(P = NS vs echocardiography). Significant stenosis was detected in 123 (49%) of the 252 analysed coronary arteries. The sensitivity,
specificity and accuracy of echocardiography for the regional diagnosis of coronary artery disease were 63% (CI 56%–69%),
90% (CI 86%–94%) and 77% (CI 72%–82%). Those for MIBI were 58% (CI 51%–64%), 91% (CI 87%–94%) and 75% (CI 69%–80) respectively
(P = NS vs echocardiography). Left ventricular hypertrophy was detected in 59 patients (70%) by echocardiography and did not
influence the overall or regional specificity of echocardiography or MIBI SPET. It is concluded that in hypertensive patients,
dobutamine stress echocardiography and MIBI SPET have a comparable accuracy for the overall and regional diagnosis of coronary
artery disease. Hypertensive patients with or without left ventricular hypertrophy should not be considered unsuitable candidates
for stress myocardial perfusion scintigraphy.
Received 10 July and in revised form 19 September 1997 相似文献
992.
Ruptured sinus of Valsalva aneurysms are rare. We report a case in which the usual clinical manifestations were not present and the patient was initially treated as an acute pulmonary embolus. Despite three negative echocardiograms an intra-cardiac shunt was suspected because of a persistently elevated mixed venous oxygen saturation. Cardiac catheterisation confirmed the diagnosis. Surgical repair was performed and post operative recovery was uneventful. 相似文献
993.
本文对19例冠心病患者和13例健康人进行了经食道心房调搏负荷多普勒超声心动图检查,旨在观察此法对冠心病患者的诊断价值。结果表明:(1)静息状态下多普勒超声心动图各项心功能指标二组之间无显著差异(P>0.05);(2)在经食道心房调搏试验中左心室收缩指标Vmax、Vmean、VTI、SV、CO等与对照组比较有显著差异(P<0.00l),以此几项指标进行二类判别分析,符合率达93.75%。结论认为经食道心房调搏负荷多普勒超声心动图是诊断冠心病的一项较敏感、无创易行的方法。 相似文献
994.
Summary Insulin resistance and a defective insulin activation of the enzyme glycogen synthase in skeletal muscle during euglycaemia may have important pathophysiological implications in Type 2 (non-insulin-dependent) diabetes mellitus. Hyperglycaemia may serve to compensate for these defects in Type 2 diabetes by increasing glucose disposal through a mass action effect. In the present study, rates of whole-body glucose oxidation and glucose storage were measured during fasting hyperglycaemia and isoglycaemic insulin infusion (40 mU·m–2min–1, 3 h) in 12 patients with Type 2 diabetes. Eleven control subjects were studied during euglycaemia. Biopsies were taken from the vastus lateralis muscle. Fasting and insulin-stimulated glucose oxidation, glucose storage and muscle glycogen synthase activation were all fully compensated (normalized) during hyperglycaemia in the diabetic patients. The insulin-stimulated increase in muscle glycogen content was the same in the diabetic patients and in the control subjects. Besides hyperglycaemia, the diabetic patients had elevated muscle free glucose and glucose 6-phosphate concentrations. A positive correlation was demonstrated between intracellular free glucose concentration and muscle glycogen synthase fractional velocity insulin activation (0.1 mmol/l glucose 6-phosphate: r=0.65, p<0.02 and 0.0 mmol/l glucose 6-phosphate: r= 0.91, p<0.0001). In conclusion, this study indicates an important role for hyperglycaemia and elevated muscle free glucose and glucose 6-phosphate concentrations in compensating (normalizing) intracellular glucose metabolism and skeletal muscle glycogen synthase activation in Type 2 diabetes. 相似文献
995.
感染性脑水肿病儿在感染得到有效控制,应用654—2(山莨菪碱)后未再用脱水剂,笔者认为.654—2具有解除脑血管痉挛及微循环障碍的作用。急性脑水肿在脱水剂应用后,用654—2有利于脑水肿液的吸收和回流。目前,治疗小儿捂热综合征(IMS)之细胞内水肿仍没有有效的方法,研究结果表明654—2能改善脑细胞供氧.其还能通过解除呼吸中枢血管痉挛而治疗中枢性呼吸衰竭。 相似文献
996.
Comparison of the APACHE III, APACHE II and Glasgow Coma Scale in acute head injury for prediction of mortality and functional outcome 总被引:1,自引:0,他引:1
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
997.
TuberculosisandSchistosomiasisarethemajorcontagiousdiseaseswhicharethemostdangeroustothepeople’shealth Inordertogetridofthem ,wemustlookforamoreusefulvaccine Bythetech niquesofmolecularbiology ,2 6 0 0 0DaGlutathionStransferase (GST) genewasclonedintotheE coli MycobacteriumtransferringandexpressionvectorpBCG 2 0 0 0totransformittoMycobacteriumsmeg matismc2 15 5 (MS)andBCGseparatelyinordertoconstructrMS Sj2 6GSTvaccineandrBCG Sj2 6GSTvaccine Inthisstudy ,theBALB/cmicewereimmu niz… 相似文献
998.
目的:探讨肺CT在SARS或传染性非典型肺炎流行时鉴别肺部病变中的价值。方法:复习50例发热患者X线胸片及CT的影像特点。结果:X线胸片正常而CT检查有磨砂玻璃影最后临床诊断为传染性非典型肺炎者3例,胸片显示小片状影的在CT像上为结节灶2例;结论:肺CT比普通X线胸片显示肺内病灶准确,CT在SARS早期是发现和诊断的最佳影像检查手段。 相似文献
999.
Apolipoprotein B polymorphism and altered apolipoprotein B concentrations in Congolese blacks 总被引:1,自引:0,他引:1
Henri-Joseph Parra F. Martin F. Monard N. Ngangoué N. Copin J. M. Bard M. Qafli N. Vu Dac P. Duriez J. C. Fruchart 《Clinical genetics》1991,40(4):263-270
The immunoreactivity of apolipoprotein B (apo B) in plasma obtained from 238 unrelated black African male subjects from the People's Republic of Congo was analysed by non-competitive Enzyme Linked-Immunosorbent Assay (ELISA) with monoclonal BIP 45 anti-LDL antibody. The polymorphism detected by BIP 45 monoclonal antibody is identical to the Ag(c,g) polymorphism. Antibody BIP 45 distinguishes three apo B allotypes (immunophenotypes) encoded by the two allelic genes apo B Ag(c) and apo B Ag(g). Because of co-dominant transmission, genotypes may be inferred from allotypes, and it has been shown that BIP 45 binds strongly to the Ag(c) factor and only weakly to the allelic Ag(g) factor. Analysis of the Congolese plasma samples indicated that 67.65% of them bound BIP 45 with low affinity (Ag(c-,g+) genotype), 28.15% with intermediate affinity (Ag(c+,g+) genotype) and 4.20% with high affinity (Ag(c+,g-) genotype). According to the Hardy-Weinberg equilibrium, this corresponds to gene frequencies of 0.817 and 0.183 for the type Ag(g)/Ag(c) alleles, respectively. After adjustment for age and body-mass index, it was found that the Ag(c) allele decreases the apo B level by 9.62 mg/dl and that the Ag(g) allele increases apo B by 0.43 mg/dl. Therefore, as much as 4.30% of the genetic variance for apo B level could be accounted for by the Ag(c,g) gene locus. 相似文献
1000.
Dr. Rüçhan Ergün Ali I. Ökten Muammer Yüksel Bülent Gül Çetin Evliyaoglu Fikret Ergüngör Yamaç Taşkin 《Neurosurgical review》1997,20(1):33-37
Hydatid cysts of central nervous system are rare and comprise only 2% to 3% of all hydatid cysts reported. Orbital localization is very uncommon and has been reported less than 1 % of all hydatid diseases. The primary treatment of hydatid disease is surgical. The most important complication of the surgical treatment is secondary hydatidosis due to spillage of the cyst contents. Because of the difficulties of the orbital localization, total extirpation of the cysts without rupture is almost impossible. Preventing spontaneous rupture of the cysts during surgery and postoperative antihelmintic treatment should be taken into consideration in these cases.This study includes four cases who underwent surgery for orbital hydatid cysts. Radiological characteristics, operative technique and postoperative medical therapy are discussed. 相似文献