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11.
In order to evaluate in vivo single-photon emission tomography (SPET) method of assessing cerebral function after hypoxic-ischemic injury in human neonates, we studied D1 and D2 dopamine receptors in a rat model. Seven-day-old rats underwent permanent unilateral common carotid ligation followed by exposure to 8% O2. Two weeks later, in brains with no visible loss of hemispheric volume, striatal dopaminergic receptors were studied, with [125I]TISCH and [1251]IBZM for the D1 and D2 dopamine receptors, respectively. Using [125I]TISCH, we observed no modifications of D1 receptors, but in contrast, ex vivo and in vitro autoradiographic experiments showed a 40% decrease in the striatal binding of [125I]IBZM on both the ipsilateral and the contralateral side to the carotid ligation. These alterations were detected with IBZM, a D2 dopamine receptor ligand usable for SPET imaging. Therefore, exploration of D2 receptors by SPET in human neonates suffering from perinatal hypoxia-ischemia may be valuable for the diagnosis and follow-up of cerebral function damages. Correspondence to: D. Guilloteau  相似文献   
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A radio experiment carried out over many years, added to previous clinical tests, has shown a sustained interest of the people for using preconscious (subliminal) suggestions combined with soothing music, as a relaxation technique. The purpose of this study was to compare systematically some combinations with their own components, i.e. the suggestions alone or the music alone. Moreover, drawing inspiration from the works of a Bulgarian psychiatrist, Georgi Lozanov, there were comparisons made of the efficacy of three types of combinations whether they included different kinds of suggestions: preconscious, close to the level of consciousness or conscious. Thirty-five (35) persons were subjected to tests in five experimental sessions, (music alone, three suggestion-music combinations, and suggestions alone), according to a latin-square design (5 x 5). Physiologic and psychologic measurements were used. The physiologic measurements did not show any significant difference between the various treatments. On the other hand, the psychologic measurements favoured the combinations rather than their components alone and specially the combination where suggestions were of an intensity close to the level of consciousness.  相似文献   
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Objective: To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. Methods: We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. Results: We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n = 19; local recurrence, n = 17; or metastasis, n = 11). There were 50 males and 19 females with a mean age of 60 years (range, 29–80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p = 0.005), coronary artery disease (p = 0.03), removal of the right lung (p = 0.02), advanced age (p = 0.02), and renal failure (p < 0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p = 0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p = 0.04) and mechanical stump closure (p = 0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Conclusion: Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival.  相似文献   
15.
Electrocardiographic imaging (ECGI) is a developing imaging modality for cardiac electrophysiology and arrhythmias. It reconstructs epicardial potentials, electrograms, and isochrones from electrocardiographic body-surface potentials noninvasively. Current ECGI methodology employs Tikhonov regularization, which imposes constraints on the reconstructed potentials or their derivatives. This approach can sometimes reduce spatial resolution by smoothing the solution. Accuracy depends on a priori knowledge of solution characteristics and determination of an optimal regularization parameter. These properties led us to implement an independent, iterative approach for ECGI—the generalized minimal residual (GMRes) method—which does not apply constraints. GMRes was applied to experimental data during activation/repolarization of normal and infarcted hearts. GMRes reconstructions were compared to Tikhonov reconstructions and to measured gold standards in isolated hearts. Overall, the accuracy of GMRes solutions was similar to Tikhonov regularization. However, in certain cases GMRes recovered localized potential features (e.g., multiple potential minima), which were lost in the Tikhonov solution. Simultaneous use of these two complementary methods in clinical ECGI will ensure reliability and maximal extraction of diagnostic information in the absence of a priori information about a patient's condition.© 2003 Biomedical Engineering Society. PAC2003: 8719Hh, 8757Gg  相似文献   
16.
The orders of three endocervical specimens of 3,561 women for Chlamydia trachomatis testing were randomized to determine whether test performance measures of two nucleic acid amplification tests and a DNA probe were affected by swab order. Specimen collection order did not appear to affect the diagnostic accuracy of these tests.  相似文献   
17.
Demonstration of IgE-sensitized mast cells in human heart and kidney   总被引:1,自引:0,他引:1  
We report the direct demonstration of IgE-bearing mast cells in human heart and kidney, as shown by immunohistochemical methods. This finding lends further support to the role of mast cells and IgE in the direct involvement of these two organs in immediate-type allergic reactions.  相似文献   
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The bioavailability of calcium (Ca) was assessed in 11 foodstuffs of plant or animal origin using rat feeding experiments and the criteria used for assessing the bioavailability were femur Ca and calcium efficiency. The bioavailability of Ca was found to be highest in fishes (Melouha) and cheeses (Mesh) fermented under local processing techniques. Germination of faba beans also enhanced the bioavailability of calcium to a mean value quite comparable to those of some dairy products, such as cottage cheese. The present study clearly demonstrates that the processes of fermentation and germination of selected foods are associated with an enhancement in the bioavailability of calcium. It is suggested that the breakdown of complex proteins under the fermentation or germination process is the underlying mechanism of action.  相似文献   
20.
There has been considerable confusion between true congenital dislocation of the patella and other patellar instabilities. Only very few papers describing the anatomical features of congenital dislocation of the patella are found in the literature. The purpose of this paper was to describe the anatomical anomalies found in two cadaver specimens of a true permanent and irreducible congenital patellar dislocation. The quadriceps femoris is short and displaced laterally and acts as a knee flexor. The patella is small, articulating with the outer aspect of the lateral condyle, with no possibility of medial reduction onto the trochlea. Many other anomalies involving the bones, muscles, and nervous structures were found. Congenital dislocation of the patella must be distinguished from other patellar dislocations in children. The severity of structural anomalies is mainly owing to its prenatal onset. Congenital  相似文献   
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