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61.
62.
We examined more than 1,400 dermatologic patients with clinically defined (but having unknown or presumably multiple etiology) affections. The investigation revealed the presence of antitoxoplasma antibodies in more than 50% of the patients, but in only 11% of the cases did the serological analyses give evidence of an active form of disease. It was possible to prove the toxoplasmic etiology of 29 cases of chronic prurigo and of 4 cases of dermatocellulitis. The same infection was involved in a few cases of different dermatoses and in two cases of dermatomyositis-like syndrome. Pseudotumoral granulomatous localizations occurred in immunosuppressed patients. We suggest an 'immunological key' to explain the polymorphism of the cutaneous manifestations. The practical interest of this new knowledge and its importance as a field of interdisciplinary studies are emphasized.  相似文献   
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Blood flow imaging with MR: spin-phase phenomena   总被引:2,自引:0,他引:2  
von Schulthess  GK; Higgins  CB 《Radiology》1985,157(3):687-695
Blood flow phenomena occurring when flow is within the magnetic resonance (MR) imaging plane were analyzed. In this situation, the signal intensity of vascular lumina is predominantly determined by spin-phase change phenomena, and section transition effects of moving spins can be neglected. In this paper, we develop the concepts of in-plane flow, with emphasis on the notion that the spatial variations in velocity and acceleration of blood, which mainly occur along vessel walls, are important determinants of intravascular signal loss in MR images. Flow patterns in the large mediastinal arteries were qualitatively and quantitatively analyzed in six healthy subjects and 14 patients with hemodynamic abnormalities using multiple electrocardiograph-gated image acquisition; ungated studies of 30 patients were analyzed for venous flow effects. Intraluminal signal was strongly dependent on the phase of the cardiac cycle and the echo number. Signal loss was found to occur along vessel walls, in vascular bends, and at bifurcations.  相似文献   
65.

Background and purpose:

Thrombus formation is commonly associated with pulmonary arterial hypertension (PAH). Thrombin may thus play an important role in the pathogenesis and pathophysiology of PAH. Hence, we investigated the contractile effects of thrombin and its mechanism in pulmonary artery.

Experimental approach:

The cytosolic Ca2+ concentrations ([Ca2+]i), 20 kDa myosin light chain (MLC20) phosphorylation and tension development were evaluated using the isolated porcine pulmonary artery.

Key results:

Thrombin induced a sustained contraction in endothelium-denuded strips obtained from different sites of a pulmonary artery, ranging from the main pulmonary artery to the intrapulmonary artery. In the presence of endothelium, thrombin induced a transient relaxation. The contractile effect of thrombin was abolished by either a protease inhibitor or a proteinase-activated receptor 1 (PAR1) antagonist, while it was mimicked by PAR1-activating peptide (PAR1AP), but not PAR4AP. The thrombin-induced contraction was associated with a small elevation of [Ca2+]i and an increase in MLC20 phosphorylation. Thrombin and PAR1AP induced a greater increase in tension for a given [Ca2+]i elevation than that obtained with high K+-depolarization. They also induced a contraction at a fixed Ca2+ concentration in α-toxin-permeabilized preparations.

Conclusions and implications:

The present study revealed a unique property of the pulmonary artery. In contrast to normal arteries of the systemic circulation, thrombin induces a sustained contraction in the normal pulmonary artery, by activating PAR1 and thereby increasing the sensitivity of the myofilament to Ca2+. This responsiveness of the pulmonary artery to thrombin may therefore contribute to the pathogenesis and pathophysiology of PAH.  相似文献   
66.
In previous reports, duration of initial ventilation exceeding 1 month almost always predicts non-survival of babies with congenital myotonic dystrophy. However, a baby with this condition survived beyond infancy after 55 days' ventilation. We describe this case in detail, explain why the baby survived and highlight the importance of individualized assessment, in addition to applying general prognostic terms described in the literature.  相似文献   
67.
Anthropomorphic radiologic phantoms   总被引:1,自引:0,他引:1  
A technique is being developed for the design and fabrication of anthropomorphic phantoms for diagnostic x-ray imaging. Anatomic information extracted from actual patient radiographs is incorporated into the phantoms using computer image processing and computer-assisted machining methods. In this paper, the technique is described as applied to a breast phantom, and preliminary images that closely mimic human anatomy on radiographs are shown.  相似文献   
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Die anthroposophische Misteltherapie kann etablierte onkologische Standardtherapien im Sinne einer umfassenderen und ganzheitlichen Versorgung erg?nzen.  相似文献   
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