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BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
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We studied a cohort of 496 patients who had multiple sclerosis (MS) for at least 10 years. Ten years after disease onset, 151 had benign MS defined as an Extended Disability Status Scale (EDSS) ≤3. Between benign and non-benign patients we compared gender, age at clinical onset, relapsing–remitting or primary progressive, symptoms at onset, recovery from first relapse, time between first and second relapse, number of relapses in the first 5 years, use of immunomodulatory drugs, and EDSS scores at 2, 5 and 10 years. A multivariate regression analysis showed that a relapsing–remitting course, a low EDSS score at 5 years, and a low number of relapses in the first 5 years were predictive for benign MS at 10 years. Other factors had no additional value. Thirty-five of the 51 patients (69%) with benign MS at 10 years were still benign at 20 years. A low 10-year EDSS score was the only clinical variable associated with a benign course at 20 years. Our results suggest that within the first 5 years from onset it is not possible to predict a benign course. Disease course, EDSS score and relapse rate at 5 years are predictors for benign MS at 10 years.  相似文献   
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The distribution of parvalbumin-like immunoreactivity was studied in the embryonic and postnatal chicken retina. In post-hatched chickens, parvalbumin-like immunoreactivity was confined to amacrine cells. Three distinct subpopulations were identifiable based upon soma position and level of dendritic arborization in the inner plexiform layer. The primary dendrites from parvalbumin-immunoreactive amacrine cells descended vertically into the inner plexiform layer and eventually branched to give rise to a laminarly arrayed plexus in sublamina I, sublamina V and, to a lesser extent, at the boundary between sublaminae III and IV. Parvalbumin-like immunoreactive amacrine cells projecting to sublamina I of the inner plexiform layer were consistently monostratified. Some, but not all, contributed thick fibers to sublamina I that could be followed for long distances across the retina and were generally not radially organized. The parvalbumin-like immunoreactive cells that projected to sublamina V gave rise to a primary dendrite from which three to five fibers branched radially. Collateral branches of these same primary dendrites gave rise to the parvalbumin-like immunoreactive plexus at the interface between sublaminae III and IV. In prenatal chickens, parvalbumin-like immunoreactivity was not detected until embryonic day 14. At this time it appeared as a faint band at the inner nuclear layer-inner plexiform layer boundary in the central retina. By embryonic day 18 the intensity of immunoreactivity and the complexity of the arborizations of the parvalbumin-like immunoreactive dendrites approached that seen in the post-hatched chicken. In the chicken retina, parvalbumin-like immunoreactivity was displayed by morphologically distinct subpopulations of amacrine cells suggesting that these amacrine cells may subserve diverse functions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Summary The case is presented of a patient showing multiple subcortical haemorrhages after lumbar metrizamide myelography. This complication after intrathecally administered metrizamide contrast medium appears not to have been reported before. Several different possible explanations are proposed for the phenomena observed in this case.  相似文献   
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols.  相似文献   
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Monoclonal antibodies directed against nicotinic acetylcholine receptors (nAChRs) were used to identify and characterize cholinoceptive neurons in the chick retina. Two monoclonal antibodies (mAbs), mAb 210 and mAb 270, stained many neurons in both the inner nuclear layer (INL) and ganglion cell layer (GCL). A class of large labeled cells in the inner INL were positioned at the INL/IPL (inner plexiform layer) border and resembled displaced ganglion cells (DGCs). Their identity was confirmed with injections of rhodamine-labeled microspheres into the ventral tectum and nucleus of the basal optic root (nBOR). Four days after the injection, large nAChR-positive neurons in the inner INL were labeled with beads. The distribution of these cells matched that reported for DGCs in the chicken and pigeon (Reiner et al., 1979; Fite et al., 1981). Many smaller cells in the INL also exhibited nAChR immunoreactivity. These cells were not retrogradely labeled after bead injections into retinal recipient areas. Their processes entered IPL where they arborized in a band comprised of the inner leaflet of lamina 1 and all of lamina 2. In some instances, a process continued inward to lamina 4. These neurons were tentatively identified as amacrine cells because of their position and branching pattern. Approximately 12-18% of the cells in the GCL exhibited nAChR immunoreactivity. Many of these cells could be classified as ganglion cells as their axons were also labeled following exposure to nAChR antibodies. Their distribution mirrored that of all ganglion cells with a higher density of cells in the central retina than in the periphery (Ehrlich, 1981). A "double label" technique was used to compare the distribution of nAChR-positive neurons with that of the choline acetyltransferase-positive (ChAT), cholinergic neurons in the chick retina. The two antigens were visualized with two different fluorophores: FITC and RITC. We were unable to find any cells in either the INL or GCL that exhibited both ChAT- and nAChR-like immunoreactivity. The nAChR-positive cells and the ChAT-positive cells both arborized in two bands within the IPL. The patterns were in perfect register in the inner IPL (lamina 4). But, in the outer IPL, the nAChR-positive dendrites were observed in the inner leaflet of lamina 1 and in all of lamina 2 while the ChAT-positive dendrites did not extend into the innermost portion of lamina 2.  相似文献   
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BACKGROUND: Communication with patients on end-of-life decisions is a delicate topic for which there is little guidance.AIM: To describe the development of a guideline for GPs on end-of-life communication with patients who wish to die at home, in a context where patient autonomy and euthanasia are legally regulated. DESIGN OF STUDY: A three-phase process (generation, elaboration and validation). In the generation phase, literature findings were structured and then prioritised in a focus group with GPs of a palliative care consultation network. In the elaboration phase, qualitative data on patients' and caregivers' perspectives were gathered through a focus group with next-of-kin, in-depth interviews with terminal patients, and four quality circle sessions with representatives of all constituencies. In the validation phase, the acceptability of the draft guideline was reviewed in bipolar focus groups (GPs-nurses and GPs-specialists). Finally, comments were solicited from experts by mail. SETTING: Primary home care in Belgium. SUBJECTS: Participants in this study were terminal patients (n = 17), next-of-kin of terminal patients (n = 17), GPs (n = 25), specialists (n = 3), nurses (n = 8), other caregivers (n = 2) and experts (n = 41). RESULTS: Caregivers and patients expressed a need for a comprehensive guideline on communication in end-of-life decisions. Four major communication themes were prioritised: truth telling; exploration of the patient's wishes regarding the end of life; dealing with disproportionate interventions; and dealing with requests for euthanasia in the terminal phase of life. Additional themes required special attention in the guideline: continuity of care by the GP; communication on foregoing food and fluid; and technical aspects of euthanasia. CONCLUSION: It was feasible to develop a guideline by combining the three cornerstones of evidence-based medicine: literature search, patient values and professional experience.  相似文献   
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