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A detailed analysis of the extent of coronary artery atherosclerosis was made in 92 white subjects (66 men and 26 women) who died suddenly from ischaemic heart disease. Stenoses resulting in loss of greater than or equal to 75% of luminal cross sectional area (significant stenosis) were found in 90 subjects and these were more extensive in the proximal coronary tree than in the distal. Thirty nine per cent had triple vessel disease, 37% had double vessel disease, and 23% had single vessel disease. In addition one man had an isolated significant stenosis affecting the left main coronary artery. The frequency of significant stenoses in the left main coronary artery was greater in men than in women. The arteries that were least affected were the distal branches of the right coronary artery. A notable feature was the widespread nature of the coronary atherosclerosis: only 26 of the total of 1840 segments of coronary artery examined in the 92 victims could be described as having a normal intima (less than or equal to 10% loss of the area within the internal elastic lamina).  相似文献   
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OBJECTIVE: To analyse early and late mortality after coronary artery bypass grafting (CABG) in patients with and without left main coronary artery (LMCA) stenosis during the 30-year period 1970-1999. METHODS: A total of 1888 of 10,647 patients (18%) who underwent a first isolated CABG at the Karolinska Hospital in Stockholm, Sweden, during 1970-1999 had significant left main coronary artery stenosis. The Swedish National Cause of Death Register was used to determine mortality up to five years after the operation. RESULTS: The proportion of patients with LMCA stenosis of all CABG patients increased from 7% during the 1970s to 26% in 1999. During 1970-1984 early mortality was 5.8% in patients with LMCA stenosis compared with 1.5% in patients without LMCA stenosis (odds ratio (OR) 3.7 (95% confidence interval (CI) 1.8-7.6)). The corresponding rates during 1995-1999 were 2.0% versus 2.2% (OR 0.8 (95% CI 0.5-1.5)), respectively. The increased risk of early death in patients with LMCA stenosis was neutralised in males during 1985-1994 and in females during 1995-1999. Five-year survival in males was 88% after operations performed during 1994-1999 compared with 82% after CABG performed during 1970-1984. Five-year mortality, exclusive of early deaths, during 1970-1984 was higher in patients with LMCA stenosis (12.8%) than in those without (8.4%) (relative risk 1.7 (95% CI 1.1-2.5)). An increased risk of late mortality in patients with LMCA stenosis was neutralised in males during 1985-1994 and in females during 1995-1999. CONCLUSIONS: During 1970-1999 there was a decrease of early and five-year mortality in patients with LMCA stenosis after CABG despite increase of patient age and risk factors. There were gender differences so that the risk of death in patients with compared with in those without LMCA stenosis was neutralised in males during 1985-1994 and in females during 1994-1999. The continuous decline of mortality during three decades most likely reflects improvement of the peri- and postoperative management of patients undergoing CABG during this period.  相似文献   
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A comparison of three methods of repairing the hard palate.   总被引:2,自引:0,他引:2  
OBJECTIVE: To compare growth, speech, and nasal symmetry outcomes of three methods of hard palate repair. PATIENTS: Consecutive available records of children born with unilateral bony complete cleft lip and palate over the period 1972 to 1992. INTERVENTIONS: Identical management of lip, nose, alveolus, and soft palate. Hard palate repair by Cuthbert Veau (CV) from 1972 to 1981, von Langenbeck (vL) from 1982 to 1989, or medial Langenbeck (ML) from 1989 to 1991. OUTCOME MEASURES: For growth: GOSLON yardstick or 5-year model index. For speech: articulation test. Nasal anemometry. For nasal symmetry: Coghlan computer-based assessment. All these measures were developed during the period of data collection but not for this project. RESULTS: There was a strong trend toward more favorable anteroposterior maxillary growth with the change from CV to vL to ML techniques. This fell short of statistical significance because of the small sample size. There was a significant reduction in cleft-related articulation faults (p =.01) considered to be related to improved arch form. In the absence of improved rates of velopharyngeal insufficiency or nasal symmetry, increased surgical experience was discounted as a significant contribution to improved growth and articulation outcomes. CONCLUSIONS: Reduced periosteal undermining and residual exposed palatal shelf from CV to vL to ML improved incisor relationships and articulation.  相似文献   
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Twenty-two members of 18 families with autism have been examined for the presence of mutations and abnormal methylation in the FMR-1 region at Xq27.3. All patients fulfilled diagnostic criteria of infantile autism. A characteristic pattern of insertion and methylation were detected after Southern blot analysis in 7 autistic individuals expressing the fragile site at Xq27.3. Normal DNA patterns were observed in 15 autistic boys cytogenetically negative for the fragile site. The results indicate a lack of involvement of the FMR-1 region in infantile autists negative for fragile X expression. © 1992 Wiley-Liss, Inc.  相似文献   
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The tryptophan photoproduct 6-formylindolo[3,2-b]carbazole (FICZ) exhibits the highest aryl hydrocarbon receptor (AhR) binding affinity reported so far. In different cells, in vitro, both extracts of UV-irradiated tryptophan and the synthesized pure compound FICZ induce a rapid and transient expression of AhR-regulated genes. The transient induction suggests that the biotransformation gene battery induced by AhR activation takes part in a metabolic degradation of the ligand, whereby a low steady-state level is regained. The down-regulation of AhR-regulated gene expression was previously shown to be dependent on cytochrome P450 1A1 (CYP1A1). Metabolism of FICZ generates five major metabolites, which appeared as three peaks (M1-M3) in the high performance liquid chromatography. The aim of the present study was to use rat liver S9 from Aroclor-pretreated rats to produce large enough quantities of FICZ metabolites for structure characterization and to determine their product precursor relationship. NMR analysis of large combined fractions of the metabolites indicated that M3 and M2 contained 2 isomers, respectively. By means of liquid chromatography-mass spectrometry (negative ion electrospray mode) and NMR spectroscopy (by (1)H-NMR, correlation spectroscopy, and nuclear Overhauser effect spectroscopy techniques) five metabolites of FICZ were identified, and their structures were elucidated. The molecular weights of the two M3 isomers were 300 and both M2 and M1 compounds demonstrated molecular weights of 316, corresponding to addition of one (M3) and of two oxygen (M2 and M1), respectively. The structures were assigned as 2- and 8-hydroxy (M3), 2,10- and 4,8-dihydroxy (M2) and 2,8-dihydroxy derivatives of indolo[3,2-b]carbazole-6-carboxaldehyde (6-formylindolo[3,2-b]carbazole).  相似文献   
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