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Malignant atrophic papulosis is an uncommon vasculopathy affecting multiple systems and frequently associated with a poor prognosis. We describe a 56-year-old patient with this rare disorder whose death was the result of intestinal involvement. Clinical diagnostic features of malignant atrophic papulosis as well as the main therapeutic approaches suggested in the literature are presented herein.  相似文献   
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POEMS syndrome is characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal protein and skin changes. This polyneuropathy belongs to the chronic inflammatory demyelinating polyradiculoneuropathies (CIDP) group. Sporadic reports have emphasized the clinical association between CIDP and central nervous system (CNS) demyelination, but as far as we know not in the context of POEMS syndrome. We report the case of a 67 years old patient who developed POEMS syndrome associated to Castleman's disease, characterized by demyelinating polyradiculoneuropathy, hepatosplenomegaly, mediastinal and supraclavicular adenopathies and monoclonal IgG lambda gammapathy. Cranial magnetic resonance imaging disclosed diffuse alteration of the cerebral white matter highly suggestive of demyelination. CNS demyelination can be another feature of POEMS syndrome. Cranial MRI should be performed in patients with POEMS syndrome in order to verify this new feature.  相似文献   
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Postnatal adaptation of brain circulation in preterm infants   总被引:4,自引:0,他引:4  
Global and regional postnatal cerebral circulatory changes in stable preterm infants were studied, and their relation to brain injury was assessed. Thirty-five preterm infants were studied on the first and second days of age. Cerebral blood flow (CBF) (mL/hg per min) and cerebral blood volume (CBV) (mL/hg) were measured using near-infrared spectroscopy. The cerebral blood flow velocity (cm/second) (peak systolic, diastolic flow, mean flow) and resistance index (RI) were determined in the internal carotid, anterior cerebral, and striate arteries by color Doppler flow imaging. Serial cerebral ultrasound studies were performed to detect changes in brain parenchymal echogenicity or intraventricular hemorrhage (IVH); the maximum severity of these findings was considered. CBF and cerebral blood flow velocity increased significantly with time, and such changes were independent of mean blood pressure, PO(2), PCO(2), hematocrit, or glycemia. In contrast, CBV and RI remained unchanged. According to the results of sonograms, no differences were found in postnatal CBF and cerebral blood flow velocity changes, regardless of whether patients had or did not have parenchymal lesions or IVH. However, higher CBV values were found on the second day in infants with IVH compared with infants without IVH. Early coupling of CBF and metabolic demands is independent of blood pressure. Improved venous return, instead of vasodilation, could be important in this adaptation.  相似文献   
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Recent studies have suggested that cannabinoids might initiate the consumption of other highly addictive substances, such as opiates. In this work, we show that acute administration of Delta9-tetrahydrocannabinol in mice facilitates the antinociceptive and antidepressant-like responses elicited by the endogenous enkephalins protected from their degradation by RB 101, a complete inhibitor of enkephalin catabolism. This emphasizes the existence of a physiological interaction between endogenous opioid and cannabinoid systems. Accordingly, Delta9-tetrahydrocannabinol increased the release of Met-enkephalin-like material in the nucleus accumbens of awake and freely moving rats measured by microdialysis. In addition, this cannabinoid agonist displaced the in vivo [3H]diprenorphine binding to opioid receptors in total mouse brain. The repetitive pretreatment during 3 weeks of Delta9-tetrahydrocannabinol in mice treated chronically with morphine significantly reduces the naloxone-induced withdrawal syndrome. However, this repetitive administration of Delta9-tetrahydrocannabinol did not modify or even decrease the rewarding responses produced by morphine in the place preference paradigm. Taken together, these behavioural and biochemical results demonstrate the existence of a direct link between endogenous opioid and cannabinoid systems. However, chronic use of high doses of cannabinoids does not seem to potentiate the psychic dependence to opioids.  相似文献   
87.
Centrilobular emphysema: CT-pathologic correlation   总被引:5,自引:0,他引:5  
Over a 5-year period, 25 patients who had undergone chest computed tomography (CT) died and were autopsied. Their lungs were fixed in the inflated state and were assessed for the presence and severity of centrilobular emphysema (CLE). Three radiologists independently evaluated the CT scans for nonperipheral low-attenuation areas, peripheral low-attenuation areas, pulmonary vascular pruning, pulmonary vascular distortion, and pulmonary density gradient. The CT criterion that best correlated with the presence and severity of CLE was the nonperipheral low-attenuation area. With this CT criterion, lung destruction was correctly identified in 13 of 15 cases. The absence of this criterion resulted in correct identification of eight of ten normal lungs. These preliminary data suggest that CLE can be reliably identified and quantified with current CT scanners.  相似文献   
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Ohne ZusammenfassungMittheilungen aus dem pharmakologischen Experimentalcursus von Prof. Th. Husemann in Göttingen  相似文献   
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