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81.
The prevalence of hyperlipidaemia and related clinical features was examined in 205 individuals with insulin-dependent diabetes mellitus. Overall, 40 per cent (82) of the individuals had hyperlipidaemia. Whilst the prevalence of hypertriglyceridaemia and combined hyperlipidaemia was greater in patients with insulin-dependent diabetes mellitus than non-diabetics, this was not the case for hypercholesterolaemia. Hyperlipidaemia was present in older patients, and the daily insulin dose and levels of HbA1 were highest in those with combined hyperlipidaemia. In addition normolipidaemic subjects had the lowest levels of serum creatinine. Triglyceride levels were predicted (in order of importance) by insulin dose, age at diagnosis, HbA1 and body mass index, whilst cholesterol levels were predicted by the age at the time of study, body mass index, urinary protein excretion, and levels of fasting blood glucose and HbA1. Hyperlipidaemia is common in insulin-dependent diabetes mellitus, and may be particularly apparent in older patients and/or those with early renal dysfunction or poor glycaemic control.  相似文献   
82.
83.
Lipoprotein (a) is a subspecies of low-density lipoprotein whichpossesses as part of its protein moiety a mutant form of plasminogentermed apolipo-protein (a), and which may be closely relatedto the risk of ischaemic heart disease and cerebral infarction.We have investigated the serum concentrations of lipoprotein(a) and other lipoproteins in 24 male patients on CAPD and comparedthem to healthy men (n= 100) and to age-matched healthy controls(n=38). The most striking finding was a substantial elevationof serum lipoprotein (a) in CAPD patients in whom it was 46.9(2.2–168) mg/dl (median and range) compared to 9.0 (<0.6–87.4)mg/dl in healthy control group and 6.7 (< 0.6–84.2)mg/dl in age-matched controls (both P<0.001). Patients, whencompared to healthy men, also had significantly increased serumtriglycerides (median and range, 1.94 (0.55–8.00) versus1.24 (0.36–4.40) mmol/1; P< 0.001), very-low-densitylipoprotein cholesterol (median and range, 0.98 (0.10–3.71)versus 0.46 (0.10–1.17) mmol/l; P<0.001), and lower-high-densitylipoprotein cholesterol (mean±1 sd, 1.26±0.29versus 1.35±0.31 mmol/l). Of these, however, only thedifference in very-low-density lipoprotein cholesterol remainedstatistically significant (P< 0.001) in comparison to age-matchedcontrols. The marked elevation of serum lipoprotein (a) in patientson CAPD may be due to increased hepatic synthesis as a consequenceof the substantial amounts of plasma proteins lost in the dialysate.Elevated serum lipoprotein (a) concentrations in CAPD patientsmay contribute to their risk of coronary artery disease.  相似文献   
84.
85.
The Role of Paraoxonase 1 Activity in Cardiovascular Disease   总被引:2,自引:0,他引:2  
The antioxidant activity of high density lipoprotein (HDL) is largely due to the paraoxonase (PON) 1 located on it. Experiments with transgenic PON1 knockout mice indicate the potential for PON1 to protect against atherogenesis. This effect of HDL in decreasing low density lipoprotein (LDL) lipid peroxidation is maintained for longer than that of antioxidant vitamins and could therefore be more protective. Several important advances in the field of PON research have occurred recently, not least the discovery that two other members of the PON gene family -PON2 and PON3 - may also have important antioxidant properties. Significant advances have been made in understanding the basic biochemical function of PON1 and the discovery of possible modulators of its activity. Case-control studies of PON1 activity and coronary heart disease (CHD) have shown a clear association between CHD and low serum PON1 activity. This relationship has been further strengthened by the publication of the first prospective study showing low serum PON1 activity to be an independent predictor of new CHD events. Furthermore, decreased CHD risk has been revealed by meta-analysis to be associated with the polymorphisms of PON1, which are most active in lipid peroxide hydrolysis. Although this is likely to be an underestimate of the true contribution of PON1 to CHD (because these polymorphisms explain only a small component of the variation in PON1 activity), it is important because genetic influences are unlikely to be confounded by other factors linked with both CHD and diminished PON1 activity. PON1 is being extensively researched and it is hoped that therapeutic approaches will emerge to increase its activity. Clinical trials of these, if successful, will not only provide a novel means of preventing atherosclerosis, but also provide a more satisfactory means of testing the oxidant hypothesis of atherosclerosis than antioxidant vitamin supplementation has proved to be.  相似文献   
86.
We have studied the relationship between sodium-lithium countertransport, determined in childhood, and family history of hypertension. Countertransport was measured in healthy children and those with secondary hypertension. There was no significant difference in countertransport between these two groups. In the normal children ( n = 52, median age 6.8 years), there was a positive relationship between body mass index and countertransport (rs= 0.34, p <0.02). A positive relationship between family history of hypertension using a ranked scoring system, and countertransport, not related to age, body mass or blood pressure (n = 34, rs= 0.63, p<0.001 ) was also found. There was no significant relationship between intraccllular sodium concentration and countertransport. These data confirm that countertransport in normal children is related to body mass index and indicate that a genetic predisposition to primary hypertension marked by sodium-lithium countertransport is identifiable in childhood.  相似文献   
87.
Although the character of acquired immunodeficiency syndrome is changing into a chronic illness, it is estimated that by the end of this century, 80 000 children and adolescents in the United States will be orphaned by parental death caused by human immunodeficiency virus infection. Plans for these children need to be made to ensure not only a stable, consistent environment that provides love and nurturing, but also the medical and social interventions necessary to cope with the tragic loss. Pediatricians should become aware of local laws and community resources and initiate discussion early in the course of parental illness to facilitate planning for the future care and custody of the children. States need to adopt laws and regulations that provide flexible approaches to guardianship and placement of children orphaned by acquired immunodeficiency syndrome.  相似文献   
88.
A multidetector computed tomography (MDCT) was installed in our department. Referral rates, examination protocols and detection rates of abnormal findings in CT examinations for cervical spine trauma 6 months before and 6 months after MDCT installation were compared to look for changes in practice. Retrospective analysis of all CT cervical spine examinations in patients with multiple trauma over two contiguous 6-month periods: from July 2003 to December 2003 (helical CT) and from January 2004 to June 2004 (MDCT). Variables recorded were number of CT examinations performed, scan plane coverage and traumatic abnormalities detected. Phantom dosimetry measurements for cervical spine examination in both helical CT and MDCT were compared. One hundred and fifty four patients underwent cervical spine CT during these periods. Helical CT period: of 91 patients undergoing CT cervical spine examination for trauma, 65 (71%) were complete cervical examinations and 26 (29%) were level-specific examinations. Eight patients (9%) had cervical spine fracture, six of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 24.76, 1.86 and 0.21 mGy, respectively, for complete cervical spine examinations. MDCT period: of 63 patients who underwent CT cervical spine examination for trauma, 61 (97%) were complete examinations and 2 (3%) were level-specific examinations. Six patients (11%) had cervical spine fracture, three of which were apparent on radiographs. Dose estimations for thyroid, lens and breast were 75.8, 9.7 and 0.7 mGy, respectively, for complete cervical spine examinations, which were notably higher than those for helical CT. After installation of MDCT, clinical requests for complete examination of the cervical spine following trauma increased. This changing trend resulted in a significantly higher radiation dose to thyroid, lens and breast.  相似文献   
89.
90.
Utilising a combination of m-aminophenyl-borate affinity chromatography and an immunoradiometric assay for apolipoprotein B (apo B), we have developed a specific and highly sensitive (6 ng/ml) procedure for the assay of glycated apo B. We studied 52 diabetic patients, 50 non-diabetic control subjects and 12 patients heterozygous for familial hypercholesterolaemia (FH). Both insulin-dependent and non-insulin dependent diabetics were included in our study. Total apo B in the diabetics (108 +/- 5 mg/dl; mean +/- S.E.M) was increased (controls: 95 +/- 4 mg/dl; P less than 0.05). In the FH group the serum apo B concentration (216 +/- 24 mg/dl) was significantly higher (P less than 0.001) than both the other groups studied. Both the serum glycated apo B concentration (9.3 +/- 0.8 mg/dl versus 4.8 +/- 0.7 mg/dl) and the percentage glycated apo B (7.9 +/- 0.4% compared to 3.9 +/- 0.2%) were significantly higher in the diabetics than in non-diabetic controls (P less than 0.001). A positive correlation was found between the percentage of glycated apo B and glycated haemoglobin (r = 0.65; P less than 0.001) and fasting glucose concentration (r = 0.52; P less than 0.001) in diabetics. The percentage of glycated apo B in FH patients was not significantly different from controls, but the serum concentration of glycated apo B, because of the greatly increased total level of apo B was raised (8.2 +/- 1.4 mg/dl) to a similar extent to that of the diabetics.  相似文献   
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