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101.
D Marazziti U Bonuccelli A Nuti C Toni S Pedri L Palego N Pavese C Lucetti A Muratorio GB Cassano 《Cephalalgia : an international journal of headache》1994,14(3):210-214
We investigated platelet 3 H-imipramine (3 H-IMI) binding, a putative peripheral serotonergic marker, and the activity of sulphotransferase (ST), an enzyme involved in the catabolism of catecholamines and phenolic compounds, in 14 patients suffering from migraine without aura (MWoA) and in 10 with tension-type headache (TH), as compared with a group of controls. The possible relationships between the biological parameters and clinical features were also examined. The results showed that the two groups of patients had a lower number of 3 H-IMI binding sites and a lower activity of the thermolabile form of ST, which acts preferentially on monoamine substrates, than the healthy controls, with no intergroup differences. Significant correlations between psychopathological rating scales and characteristics of the illness were observed in the patients with TH. The decreased number of platelet 3 H-IMI binding sites is suggestive of a presynaptic serotonergic dysfunction and confirms the involvement of 5HT in primary headaches. The reduced ST activity might produce changes in the level of sulphated biogenic amines, including dopamine and tyramine, which might have an additional role in the pathophysiology of some aspects of primary headache. 相似文献
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Matson GB; Twieg DB; Karczmar GS; Lawry TJ; Gober JR; Valenza M; Boska MD; Weiner MW 《Radiology》1988,169(2):541-547
Localized phosphorus-31 magnetic resonance (MR) spectroscopy in humans has previously been accomplished with surface coils by means of depth-resolved surface coil spectroscopy or rotating frame experiments, in which the extent of tissue sampled critically depends on surface coil placement. The authors' goal was to modify the surface coil image-selected in vivo spectroscopy (ISIS) experiment to accomplish three-dimensional volume selection through application of selective pulses in the presence of B0 gradients. Advantages of ISIS include the ability to use proton images to define the volume of interest (VOI) and reduced dependence on exact positioning of the surface coil. However, rapid replication of the surface coil ISIS experiment can cause spectral contamination from signals originating outside the VOI. A modified version of the ISIS experiment was developed to alleviate contamination under conditions of rapid replication. Applications of localized P-31 MR spectroscopy for observation of high-energy phosphorus metabolites are presented in human liver, heart, and transplanted and normal kidney. 相似文献
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The individual infant's neurodevelopmental process provides an integrative framework for the delivery of medical care needed to assure the infant's survival and quality of outcome. The infant's neurobehavioral functioning and expression provides an opportunity for caregivers to estimate the individual infant's current strengths, vulnerabilities and threshold to disorganization, as well as to identify the infant's strategies in collaborating in his or her best progression. This perspective supports caregivers in seeing themselves in a relationship with the infant, and in considering opportunities to enhance the infant's strengths and reduce apparent stressors in collaboration with the infant and the family. The results of several randomized studies supporting the effectiveness of such a neuro developmental approach to NICU care will be presented, and suggest implications for staff education and nursery-wide implementation. 相似文献
106.
We report the case of a 73-year-old woman successfully treated for a subacute rupture of the ventricular free wall which occurred on the fourth day after a postero-lateral myocardial infarction. Angiography performed prior to surgical repair revealed the presence of normal coronary arteries. The pathogenetic mechanism of such a happening remains uncertain, but the role of abrupt recanalization must be considered. 相似文献
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Inzunza B Orrego R Peñalosa M Gavilán JF Barra R 《Ecotoxicology and environmental safety》2006,65(2):242-251
The responses of cytochrome P4501A1 in the liver, the appearance of fluorescent metabolites in bile, and genotoxic damage in erythrocytes were studied in Oncorhynchus mykiss exposed under laboratory conditions to sediments taken from the Biobio River, central Chile. Samples were taken at four sampling sites in the Biobio River, following a pollution gradient from the discharge, where Stations 2 and 3 are impacted by a petrochemical industrial discharge effluent. Chemical analysis indicates polycyclic aromatic hydrocarbon (PAH) presence in a range of 2000 to 7000 ng g(-1) dry weight in sediments from Stations 2 and 3, respectively. Both the CYP1A1 activity and the bile metabolites of O. mykiss exposed to the PAH-contaminated sediments present statistically significant differences with respect to the other stations. Additionally, the comet assay revealed notable genotoxic damage in trout erythrocytes from Stations 2 and 3, an effect that was not observed at the other stations. 相似文献
110.
Bezon E Maguid YA Gueret G Choplain JN Aziz AA Barra JA 《The Annals of thoracic surgery》2006,81(1):383-385
We describe the wrapping of the proximal segment of the left internal thoracic artery graft in a polytetrafluoroethylene membrane. Two groups of patients were compared (99 patients with wrapping, 70 patients as controls). There were no statistical differences between the two groups regarding the postoperative course. Three patients in the polytetrafluoroethylene group and 2 in the control group underwent reoperation for valve surgery. Exposure of the wrapped graft segment for clamping was safer and more rapid than in the control group. 相似文献