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101.
OBJECTIVE: To investigate the association of retinopathy with the risk of all-cause, cardiovascular disease (CVD), and coronary heart disease (CHD) mortality in type 2 diabetic subjects in a population-based 18-year follow-up study with particular emphasis on sex differences. RESEARCH DESIGN AND METHODS: Our study cohort comprised 425 Finnish type 2 diabetic men and 399 type 2 diabetic women who were free of CVD at baseline. The findings were classified based on standardized clinical ophthalmoscopy to categories of no retinopathy, background retinopathy, and proliferative retinopathy. The study end points were all-cause, CVD, and CHD mortality. RESULTS: Adjusted Cox model hazard ratios (95% CIs) of all-cause, CVD, and CHD mortality in men were 1.34 (0.98-1.83), 1.30 (0.86-1.96), and 1.18 (0.74-1.89), respectively, for background retinopathy and 3.05 (1.70-5.45), 3.32 (1.61-6.78), and 2.54 (1.07-6.04), respectively, for proliferative retinopathy and in women 1.61 (1.17-2.22), 1.71 (1.17-2.51), and 1.79 (1.13-2.85), respectively, for background retinopathy and 2.92 (1.41-6.06), 3.17 (1.38-7.30), and 4.98 (2.06-12.06), respectively, for proliferative retinopathy. CONCLUSIONS: Proliferative retinopathy in both sexes and background retinopathy in women predicted all-cause, CVD, and CHD death. These associations were independent of current smoking, hypertension, total cholesterol, HDL cholesterol, glycemic control of diabetes, duration of diabetes, and proteinuria. This suggests the presence of common background pathways for diabetic microvascular and macrovascular disease other than those included in the conventional risk assessment of CVD. The sex difference observed in the association of background retinopathy with macrovascular disease warrants closer examination.  相似文献   
102.
Six healthy volunteers received 15 mg midazolam, 50 mg ephedrine, or placebo orally before a 50-minute aerobic treadmill exercise and in a control session. Plasma drug concentrations for pharmacokinetic calculations were estimated from samples drawn up to 24 hours after drug intake. Heart rate, blood pressure, critical flicker fusion test, Maddox wing test, and visual analog scales relating to mood and feelings of tiredness were included in the sessions as pharmacodynamic measures. These tests were made at 35, 55, and 75 minutes and at 2, 2 1/2, 3 1/2, and 5 hours after drug intake. Exercise impaired the absorption of midazolam and counteracted the midazolam-induced decrement in flicker fusion threshold. Whether the effect on flicker fusion was caused mainly by the pharmacokinetic changes or by a general alerting effect of exercise cannot be verified by this experiment. The kinetics of ephedrine was not affected by exercise, but exercise enhanced the tachycardic response to ephedrine and abolished its pressor effect.  相似文献   
103.
Antibiotics can cause severe alterations in the gut microflora and promote diarrhoea and overgrowth of pathogenic bacteria. The present study investigated the potency of targeted recombinant beta-lactamase (TRBL) to degrade a beta-lactam antibiotic in the jejunum of fistula-operated beagles. We used different peroral doses of purified beta-lactamase (PenP) of Bacillus licheniformis in enteric-coated pellets together with intravenous ampicillin. Serum and jejunal samples were collected for ampicillin and beta-lactamase analysis. A dose-response effect of TRBL on ampicillin concentrations in the jejunal samples could be observed. The highest doses applied decreased the jejunal ampicillin concentrations to undetectable levels. In the serum samples, the ampicillin concentrations were not affected by the beta-lactamase dose used. Our results indicate that it may be possible to evolve a targeted treatment to degrade beta-lactam antibiotics intestinally and, thus, decrease antibiotic-induced adverse effects on the gut microflora.  相似文献   
104.
BACKGROUND: Large geographical variation in the incidence and mortality of cardiovascular disease (CHD) has been repeatedly reported in Finland with persistent difference between east and west. We undertook this study to estimate the geographical distribution of Acute Myocardial Infarction (AMI) incidence in the high-risk province of North Karelia and in the province of Kuopio. METHODS: Data on men aged 25-64 years with first event of acute myocardial infarction (AMI) were obtained from the FINMONICA AMI register, which recorded detailed information of AMI events during the period 1983 to 1992. The geographical pattern of AMI incidence was studied in two five-year periods 1983 to 1987 and 1988 to 1992 separately in 10 km x 10 km grid cells employing the Geographical Information System (GIS) and a Bayesian hierarchical approach. RESULTS: In both periods Bayesian modeling revealed a geographical pattern of AMI incidence and high risk (probability that incidence exceeds the observed mean incidence) in the remote rural areas. CONCLUSIONS: Detection of high-risk areas in both provinces showed that underlying environmental and/or genetic risk factors of AMI are not evenly distributed within the province but enriched in certain geographical non-administratively defined locations in eastern Finland.  相似文献   
105.
A placebo-controlled, double-blind crossover study was carried out in 11 non-insulin-dependent (type 2) diabetic patients to find out the effects of a hepatic enzyme inducer (phenobarbital, 100 mg/day for 2 months) on the metabolic control, plasma C-peptide, insulin, serum, and lipoprotein lipid levels. Phenobarbital induced a significant increase in hepatic antipyrine metabolizing activity, but no significant changes were found in fasting or postload blood glucose, plasma C-peptide, or insulin levels during the study. There was a significant increase in serum total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol, as well as in serum total and very low-density lipoprotein triglycerides, during phenobarbital treatment as compared with placebo.  相似文献   
106.
The QT/QS2 ratio in seven 21-year-old men with a history of vasomotor lability was measured when they were resting supine and during orthostatic, Valsalva and diving reflex tests. The vasolability was characterized by an abnormal sympathicotonic heart rate (HR) response to the orthostatic test and vacillating inferoapical T waves in the ECG. The results of the vasolabile subjects were compared to those of seven fit control subjects of the same age. In spite of equal HR's in both groups the vasolabile subjects' QT/Q2 ratio constantly exceeded 1.00 during the whole test protocol and it was higher than of the controls (P = 0.04). The reversed QT/QS2 relationship in the test subjects seemed to be due both to a prolongation of the QT time and a shortening of the QS2 time. This difference prevailed throughout although the reaction pattern to autonomic stimulations was equal in both groups. We considered an inadequate neural control of the heart, possibly with metabolic and haemodynamic interactions, responsible for the prolongation of the electrical systole in relation to the electromechanical systole in the heart of the vasomotorically labile subjects.  相似文献   
107.
BACKGROUND: Current methods for determination of carbohydrate-deficient transferrin (CDT) are based on separation of the CDT fraction by ion-exchange chromatography on minicolumns and quantification by immunoassay. Alternatively, the transferrin isoforms can be separated by HPLC anion-exchange chromatography and quantified by absorbance. This method has been reported to improve the validity of CDT as a marker of chronic alcohol abuse. METHODS: HPLC on either MonoQ or ResourceQ anion-exchange columns was used to separate and quantify isoforms of transferrin with detection at 460 nm. The result was expressed as the percentage of the disialo form (pI 5.7) of total transferrin (DST). The commercial CDTect assay was used as a comparison method. Serum samples from nondrinkers (n = 57), moderate drinkers (n = 77), and heavy drinkers (n = 139) were analyzed. RESULTS: In ROC analysis for differentiation between moderate and heavy drinkers, the area under the curve (AUC) for the HPLC method was 0.87 (95% confidence interval, 0.81-0.93), whereas that for CDTect was 0.72 (95% confidence interval, 0.64-0.80). At 90% specificity, the sensitivity of DST was 63% (95% confidence interval, 53-73%) compared with 33% (22-44%) for CDT. The reference interval of the HPLC method was 0.68-1.7%. CONCLUSIONS: The HPLC anion-exchange method for quantification of CDT provides substantially better separation between moderate and heavy drinkers than the CDTect method.  相似文献   
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110.
Baculovirus-mediated periadventitial gene transfer to rabbit carotid artery   总被引:14,自引:0,他引:14  
Recombinant Autographa californica multiple nuclear polyhedrosis viruses (AcMNPV) have recently been shown to transduce mammalian cells in vitro. Since baculoviruses offer many advantages over viruses currently used in gene therapy, we have tested them for in vivo gene transfer by constructing a baculovirus bearing a nuclear targeted beta-galactosidase marker gene (LacZ) under a CMV promoter. Both rabbit aortic smooth muscle cells (RAASMC) and human ECV-304 cells were susceptible to LacZ-baculovirus transduction. Transgene expression was evaluated in vivo by applying 1 x 10(9) p.f.u. of LacZ-baculoviruses or LacZ-adenoviruses in a silastic collar placed around rabbit carotid arteries in the absence of contact with blood components. As a result, baculoviruses led to transgene expression in adventitial cells in rabbit carotid arteries with efficiency comparable to adenoviruses. The beta-galactosidase gene expression was transient staying at a high level for 1 week but disappearing at the 14 day time-point. The arterial structure and endothelium remained intact in the baculovirus-transduced arteries, but macrophage-specific immunostaining detected signs of inflammation comparable to adenoviruses. Baculoviruses are thus able to mediate transient gene transfer in vivo and may become useful tools for gene therapy.  相似文献   
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