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1.
Background Extended trans septal (ETS) approach for mitral valve surgery often divides the artery to the Sino-Atrial node. The clinical implication of this is contentious. We analyzed our early results with ETS approach. Methods Between June 1998 and September 2003 eleven patients underwent mitral valve surgery by ETS approach. Six were females. Age ranged from 19 years to 67 years (median 40 years). Six underwent mitral valve replacement (MVR). Four underwent aortic and mitral (double) valve replacement (DVR). One had mitral valve repair. Three had additional procedures (tricuspid valve repair=1, Coronary artery bypass=1, Aorto bifemoral graft=1). Cardiopulmonary bypass ranged from 64 minutes to 77 minutes (median 72 minutes) for MVR and 112 minutes to 178 minutes (median 140 minutes) for DVR. Aortic cross clamp times ranged from 39 minutes to 52 minutes (median 47 minutes) for MVR and 74 minutes to 120 minutes (median 95 minutes) for DVR. Results There was no mortality or morbidity attributed to the ETS approach. One early death in emergency DVR was due to heart failure. Three patients needed seqeuntial pacing in the immediate post-operative period. Nine out of ten survivors were back to their preoperative rhythms on hospital discharge (6 sinus rhythm; 3 atrial fibrillation). One patient with preoperative trifascicular block who underwent reoperation to fix a paravalvular mitral leak needed a permanent pacemaker (VVI). The follow-up ranged from 1 month to 64 months (median 6 months) and is 100% complete. There was no late death or new arrhythmia. Conclusions Extended trans septal approach is safe. It gives excellent exposure of the mitral valve. division of the sinus node artery is not deleterious in the short to intermediate term. Presented at the 50th Annual Meeting of IACTS. New Delhi, Feb. 2004.  相似文献   
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This study compares the continuous response of six underweight (UW) (body mass index [BMI] < 18 kg/m2) and six normal-weight (NW) (20 < BMI < 25) men of similar age to a modest but sustained level of underfeeding and overfeeding. Habitual energy intake over 4 wk, body composition, and basal metabolic rate (BMR) were measured under metabolic-ward conditions. NW subjects were heavier by 9 kg and had 5% more body fat than UW subjects. The average BMR of UW subjects was 7.5% lower than NW subjects in absolute terms and also per kilogram fat-free mass per day but was higher by 8% when expressed per kilogram body weight per day. Three NW and three UW subjects were given a diet with 10% less energy than their habitual intake for 4 wk. They were brought back to the normal level of feeding for another 4 wk. Finally, they were overfed by 10% for 4 wk. This sequence was reversed in the remaining six subjects. Changes in body weight, BMR, and energy balance were assessed. UW subjects showed a quick and vigorous reduction in BMR (13.4%) during the 1st wk of underfeeding compared with NW subjects (8.1%). In the later weeks, the reduction was 8% in UW and 7% in NW subjects. Furthermore, UW subjects showed a tendency to resist a decrease in body weight (mean loss 180 g), unlike NW subjects (mean loss 730 g). With overfeeding, the mean increase in BMR for UW was higher (7.4%) than for NW (5.3%) subjects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Mosaicism for an FMR1 gene deletion in a fragile X female   总被引:2,自引:0,他引:2  
Most cases of fragile X syndrome result from expansion of CGG repeats in the FMR1 gene; deletions and point mutations of FMR1 are much less common. Mosaicism for an FMR1 full mutation with a deletion or with a normal allele has been reported in fragile X males. Here we report on a fragile X female who is mosaic for an FMR1 full mutation and an intragenic deletion. The patient is a 4-year-old girl with developmental delay, autistic-like behaviors, and significant speech and language abnormalities. Southern blotting demonstrated the presence of a methylated full mutation, a normal allele in methylated and unmethylated forms, and an additional fragment smaller than the normal methylated allele. This result indicates that the patient is mosaic for a full mutation and a deletion, in the presence of a normal allele. By DNA sequence analysis, we mapped the 5' breakpoint 63/65 bp upstream from the CGG repeat region and the 3' breakpoint 86/88 bp downstream of the CGG repeats within the FMR1 gene. The deletion removed 210 bp, including the entire CGG repeat region. The full mutation was inherited from a premutation in the patient's mother. The deletion, which remained methylated at the Eag I and Nru I sites, was probably derived from the full mutation allele. Mosaicism of this type is rare in females with a fragile X mutation but should be kept in mind in the interpretation of Southern blots.  相似文献   
4.
Steatosis is a frequent pathologic stage in alcoholic liver disease (ALD). Although the mechanisms for increased susceptibility of steatotic liver to injury have been postulated, the ability of these hepatocytes to proliferate and withstand injury is unknown. There are conflicting reports on the status of hepatocyte regeneration following chronic alcohol ingestion. Hence, the objective of this study was to investigate the temporal dynamics between the pattern of liver injury and hepatocyte proliferation during the steatosis stage of ALD. Alcoholic steatosis was induced in male Sprague-Dawley rats by feeding an ethanol (EtOH)-containing Lieber-DeCarli liquid diet for a period of 5 weeks. Microvesicular steatosis was evident in H&E sections by three weeks in the EtOH-treated rats, which further developed into panlobular macrovesicular steatosis by 5 weeks. Plasma transaminase activities indicated progressive increase in liver injury peaking at 3 weeks with significant but mild decrease at 4 and 5 weeks. CYP2E1 protein and activity was significantly increased in EtOH-fed rats as measured by Western blot and pNP hydroxylation assay. PCNA analysis of liver sections indicated that EtOH-treated rats had a significantly higher number of cells in S phase of cell division at weeks 1 (3.20 +/- 0.19), 2 (7.03 +/- 0.92), and 3 (4.23 +/- 1.41) when compared to controls (1.5 +/- 0.22). NF-kappaB DNA binding and Cyclin D1 proteins increased significantly in the EtOH-treated rats corresponding with enhanced hepatic proliferation. These data suggest the transient decline in liver injury during alcoholic steatosis is due to enhanced NF-kappaB-dependent hepatocyte proliferation.  相似文献   
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The polymerization of styrene initiated by 2,2′-azoisobutyronitrile (AIBN) was studied in N,N-dimethylformamide (DMF) solution at 60°C in the presence of tetrakis(N,N-dimethylformamide)copper(II) perchlorate, and also in the presence of its monoazido copper(II) complex [Cu(DMF)3N3]+. The monoazido complex in DMF was prepared in situ by mixing solid sodium azide with tetrakis(N,N-dimethylformamide)copper(II) perchlorate in a mole ratio of 1:1. The nature of the complex was established by Job's method. The equilibrium constant K for the reaction [Cu(DMF)4]2+ + N ? [Cu(DMF)3N3]+ + DMF determined by the limiting logarithmic method was found to be 1,25 · 104l · mol?1. The presence of [Cu(DMF)4]2+ ions in the polymerization systems caused retardation, but [Cu(DMF)3N3]+ ions produced well defined induction periods. The rate constants at 60°C for the interaction of polystyryl radical towards [Cu(DMF)4]2+ and [Cu(DMF)3N3]+ ions were calculated to be 6,6 · 102 and 5,74 · 104 l · mol?1 · s?1, respectively.  相似文献   
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The purpose of this study was to analyze whether maternal serum placental growth factor (PlGF) could predict early onset preeclampsia (<32 weeks of gestation) in overweight/obese pregnant women, and whether it could do it more effectively than in normal/underweight pregnant women. A prospective cohort study was conducted on 1678 pregnant women with singleton pregnancies, who were grouped as underweight, normal, overweight, and obese on the basis of body mass index, followed by serum PlGF estimation at 20 to 22 weeks of gestation. A cut-off value of <144 pg/mL for PlGF was determined by Receiver Operating Characteristic curve analysis to identify risk of early onset preeclampsia. Univariate logistic regression analysis revealed significantly stronger association between PlGF <144 pg/mL and early onset preeclampsia in overweight/obese pregnant women (odds ratio 7.64; 95% confidence interval 5.34–10.12; P = .000) than in normal/underweight pregnant women (odds ratio 2.95; 95% confidence interval 1.74–4.26; P = .007). Weight and PlGF levels in study women had a significant negative correlation (r = 0.663; P = .002). Serum PlGF in early second trimester could be an effective predictor of early onset preeclampsia in overweight/obese pregnant women and may be more effective than in normal/underweight pregnant women.  相似文献   
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