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Aims: To demonstrate the benefit of the combination amlodipine/valsartan 5/160 mg over amlodipine 10 mg, in producing a lower incidence of peripheral oedema for a comparable mean sitting systolic blood pressure (MSSBP) reduction. Methods: After a 4‐week amlodipine 5 mg run‐in phase, inadequately controlled hypertension patients (aged ≥ 55 years, MSSBP ≥ 130 and ≤ 160 mmHg) were randomised to receive amlodipine/valsartan 5/160 mg or amlodipine 10 mg for 8 weeks, followed by amlodipine/valsartan 5/160 mg for 4 weeks for all patients. Primary variables were MSSBP change from baseline to week 8 and incidence of peripheral oedema reported as an AE. Resolution of peripheral oedema was assessed 4 weeks after switching patients from amlodipine 10 mg to amlodipine/ valsartan 5/160 mg. Results: At week 8, MSSBP showed greater reduction with amlodipine/valsartan 5/160 mg than amlodipine 10 mg (least square mean: ?8.01 vs.?5.95 mmHg, p < 0.001 for non‐inferiority and p = 0.002 for superiority). Systolic control, overall BP control and systolic response rate at week 8 were significantly higher with combination than amlodipine 10 mg (34 vs. 26%; 57 vs. 50%; 36.57 vs. 27.77%, respectively). Incidence of peripheral oedema was significantly lower with the combination than amlodipine 10 mg (6.6 vs. 31.1%, p < 0.001). Peripheral oedema resolved in 56% patients who switched from amlodipine 10 mg to the combination, without the loss of effect on BP reduction. Conclusion: In non‐responders to amlodipine 5 mg, treatment with amlodipine/valsartan 5/160 mg induced significantly less peripheral oedema than amlodipine 10 mg for similar BP reduction. Peripheral oedema resolved in > 50% patients switching from amlodipine 10 mg to the combination.  相似文献   
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MR imaging of fetal brain malformations   总被引:3,自引:0,他引:3  
Methods From the generally accepted data on the morphogenesis of the brain, the principles for the classification of brain malformations are given, and the salient features of each malformation which may be considered as independent from the developmental stage and therefore practical for MR imaging in the fetus after mid-gestation, are discussed.Results and discussion However, the correlation with the clinical results in 150 cases of malformations out of a series of more than 1,000 cases of MR fetal brain imaging, demonstrates that beside the main, well-defined malformative entities, a significant degree of uncertainty remains. As the indication of further imaging is mainly based on the ultrasonographic findings, cases that are not identified as abnormal by US are not submitted to MRI (partial commissural agenesis and malformations of cortical development). A striking discrepancy exists between the findings of US and those of MRI, in the specific instance of the disorders of the posterior fossa (cystic malformations versus mega cisterna magna versus cerebellar defects), which may be only partly corrected by the use of strict anatomic criteria. Similar difficulties are observed for the diagnosis of nondestructive microcephaly.Conclusion Long-term prospective longitudinal clinical-radiological studies of these groups of patients are needed.  相似文献   
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In order to determine the real value of the amplitude variations of the R wave V5 during a stress test, in the recognition of coronary insufficiency, the stress tests of 227 patients were reviewed and compared to the results of coronary angiography. This permitted to find 93 patients with healthy coronaries and 134 patients presenting an involvement of the anterior inter-ventricular artery (AIVA); 37 have a one-vessel disease, 38 have a two-vessel disease, 59 a tri-vessel disease. Quantitative analysis of the modifications of the R wave in V5 during stress, finds mean values of amplitude variations of 1.46 +/- 2.65 mm (p less than 10(-7)) in the reference group; + 1.36 +/- 3.03 mm (p less than 0.01) in patients with a one-vessel disease; +/- 2.02 +/- 2.73 mm (p less than 10(-5)) in patients with two-vessel disease; +/- 1.77 +/- 2.82 mm (p less than 10(-6)) in patients with three-vessel disease. Mean variations are not significantly different from one group to the other and do not permit to individualize a specific evolutive profile in favor of a coronary disease. Considering the absence of alterations or the increase of the amplitude of R in V5 during stress as a pathological response to a coronary insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The 4 K 245-GHz/8.7-T electron paramagnetic resonance spectrum of the stable tyrosyl radical in photosystem II, known as TyrD., has been measured. Illumination at 200 K enhances the signal intensity of TyrD. by a factor of > 40 compared to the signal obtained from dark-adapted samples. This signal enhancement and the unusual line shape of the TyrD. resonance result from the magnetic dipolar coupling of the radical to the manganese cluster involved in oxygen evolution. The relative angular orientation of the manganese cluster with respect to TyrD. has been determined from line-shape analysis. The resonance arising from TyrD. in Tris-washed manganese-free photosystem II sample is also distorted. This effect probably originates from the influence of the nonheme iron on the spin relaxation of the tyrosyl radical. The relative angular orientation of the nonheme iron has also been determined. Oriented samples were used to determine the angular orientation of TyrD. with respect to the membrane plane. Combining angular data with published distances, we have constructed a three-dimensional picture of the relative positions of TyrD., the manganese cluster, and the nonheme iron. The data suggest a more symmetrical placement of the manganese relative to TyrD. and TyrZ, the tyrosine involved in electron transfer, than is usually assumed in current models of photosystem II.  相似文献   
36.
An accurate and relatively simple radioimmunoassay for the determination of aldosterone concentration in peripheral plasma has been developed, 0.5-2.0 ml plasma with added [1,2-3H]aldosterone is extracted with dichloromethane. Purification of the extract is achieved by thin later chromatography in the system benzene-acetone 1:1. Recovery of [1,2-3H] aldosterone is 58 +/- 6 (SD)%. Bound and free fractions are separated by dextran-coated charcoal. The intra-assay reproducibility is 8.8% and the inter-assay reproducibility varies from 11.4-16.1%. The sensitivity of the assay for a 5 ml plasma sample can be put at 0.2 ng/100 ml. Normal values determined in 52 healthy children of different age groups are presented. Furthermore the aldosterone stimulating effect of low sodium diet (17 children), severe and prolonged vomiting (19 children) and synthetic ACTH (10 children) has been studied by our modified method.  相似文献   
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Arterial distensibility estimated by carotid femoral pulse wave velocity was evaluated in 22 patients with sustained essential hypertension, together with 3 different methods of blood pressure (BP) measurement: mercury sphygmomanometer, semiautomatic BP recording using the Dinamap apparatus and 24-hour ambulatory BP monitoring using a Spacelabs monitor. Although pulse wave velocity did not correlate with BP measured by mercury sphygmomanometer, it strongly and positively correlated with BP measurements using the other 2 procedures. The best correlation was observed with ambulatory BP with respect to systolic BP only (r = 0.685, p less than 0.001). Since cardiovascular morbidity and mortality in hypertensive patients is mainly related to lesions of the large arteries, the determination of pulse wave velocity together with ambulatory BP measurements is proposed for the evaluation of cardiovascular risk.  相似文献   
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