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1.
AIM: Cardiovascular risk factors can be present in children and young adults. We previously found abnormal microvascular function in children who had glucose intolerance and insulin resistance. The aim of the present study was to investigate whether they also have abnormalities in left ventricular mass (LVM) and arterial stiffness. METHODS: We measured heart dimensions and LVM using echocardiography, and arterial stiffness using pulse wave analysis in 23 children with good glucose handling (postfeeding glucose: 3.9 to 5 mmol/L) and 21 with poor glucose handling (7.7 to 11.4 mmol/L). RESULTS: The time to pulse reflection was slightly shorter in the poorer glucose handlers (mean+/-SD: 143+/-10 vs 153+/-20 ms, P=0.04), suggestive of increased arterial stiffness. Also in this group, there were significant relationships between intraventricular septal thickness, blood pressure and body mass index, but not in the normal glucose handlers. CONCLUSIONS: We have found that normal children who are in the lowest quintile of glucose tolerance in comparison with their peers are exhibiting the first signs of arterial stiffening. In addition, we have seen the beginnings of a relationship between blood pressure, body mass index and left ventricular enlargement in this group. While these changes may not yet be clinically significant, their emergence might be further evidence of early predisposition to cardiovascular disease.  相似文献   
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OBJECTIVE: Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In recent years, various studies have been published stating that children with nocturnal enuresis exhibit growth and skeletal maturation retardation. METHODS: In this cross-sectional study, we included 27 patients (16 boys, 11 girls) between the ages of 6 and 14 years who had presented with primary nocturnal enuresis (PNE) complaints. We included in the evaluation 19 healthy subjects (12 boys, 7 girls), who were the siblings of the children with PNE, as the control group. RESULTS: The patients in both groups were similar in chronological age, bone age, height and weight, with no significant difference between groups (P>0.05). CONCLUSION: The two groups in our study consisted of the same genetic background. Thus, our results were found to be different from the previous studies. We have concluded that there is no direct relationship between enuresis nocturnal and skeletal maturation.  相似文献   
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Finger blood flow is decreased in Raynauds Phenomenon (RP). This may be due not only to vasospasm, but also to blood abnormalities. 40 patients with Raynauds Disease (RD), 28 with suspected RP (SS) and 42 with secondary Raynauds syndrome (RS) were enrolled and compared to 50 controls. Results from base-line samples show that those with RP have abnormal haemostasis and rheology whereas those with mild Raynauds, RD do not. Blood sampled after cold challenge in 15 RS patients and 15 controls show that both groups exhibit platelet activation after emersion. The degree of activation however was much more marked in the RS patients. We have shown that abnormalities of haemostasis and rheology are found in patients likely to have endothelial damage (RS). These changes are probably a consequence rather than a cause of the disease. After cold challenge the results become more abnormal and correlate with severity of disease.  相似文献   
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OBJECTIVE: To determine the effect of subcutaneous erythropoietin treatment on dialysis efficiency in continuous ambulatory peritoneal dialysis (CAPD) patients. DESIGN: Dialysis efficiency, platelet and white cell aggregation, and red cell deformability were measured monthly for six months in nine anaemic CAPD patients treated with erythropoietin, and on a single occasion in seven control CAPD patients with intrinsically high haemoglobin concentrations. SETTING: Renal dialysis unit. PATIENTS: Nine patients stable on CAPD for a minimum of six months and with haemoglobin concentrations less than 8.5 g/dl were treated with erythropoietin. Seven CAPD patients matched for age and renal function, with haemoglobins greater than 9.0 g/dl served as controls. RESULTS: Daily peritoneal clearances and net ultrafiltration volumes were unchanged when haematocrit increased from 25.0 +/- 2.2% to 36.5 +/- 3.5%. Spontaneous whole blood platelet aggregation was significantly increased from week twelve (pre-treatment aggregation 46 +/- 23%; 12 weeks: 67 +/- 19%, p less than 0.05; 16 weeks: 64 +/- 19%, p less than 0.01; 20 weeks: 71 +/- 16%, p less than 0.01; 24 weeks: 73 +/- 10%, p less than 0.01). CONCLUSIONS: The increase in haematocrit and platelet aggregation associated with erythropoietin treatment did not affect peritoneal clearances or ultrafiltration capacity.  相似文献   
7.
BACKGROUND: Spiral or helical arterial blood flow patterns have been widely observed in both animals and humans. The absence of spiral flow has been associated with carotid arterial disease. The aim of this study was to detect the presence of aortic spiral flow using magnetic resonance imaging (MRI) and to evaluate the relationship of the presence of spiral aortic flow with renal arterial disease and renal function in the follow-up of patients with suspected renal atheromatous disease. METHODS: Prospective study of 100 patients with suspected renal arterial disease and 44 patient controls. Using a 1.5 T MRI unit (Siemens Symphony), phase contrast flow quantification and three-dimensional contrast enhanced MR angiography of the abdominal aorta were performed. Renal arterial stenoses (RAS) were classified minimal, moderate or severe. Renal function was followed at 3 months before and 6 months after MRI. RESULTS: Non-spiral flow was more prevalent in patients with more severe RAS. Renal impairment progressed significantly in severe RAS without spiral flow (P = 0.0065), but did not progress significantly in severe RAS with spiral flow (P = 0.12). In minimal or moderate RAS with or without spiral flow there was no significant progression (P = 0.16, 0.13, 0.47, 0.092, respectively). CONCLUSIONS: Aortic spiral blood flow can be assessed with MRI. Lack of aortic spiral blood flow in patients with severe RAS is associated with significant short-term renal function deterioration. Determination of blood flow patterns may be a useful indicator of renal impairment progression in patients with suspected renal artery stenosis.  相似文献   
8.
High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.   相似文献   
9.
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons.  相似文献   
10.
PURPOSE: Malignant B lineage cells in Waldenstrom's macroglobulinemia (WM) express a unique clonotypic IgM VDJ. The occurrence of biclonal B cells and their clonal relationships were characterized. EXPERIMENTAL DESIGN: Bone marrow and blood from 20 WM patients were analyzed for clonotypic VDJ sequences, clonal B-cell frequencies, and the complementary determining region 3 profile. RESULTS: Two different clonotypic VDJ sequences were identified in 4 of 20 WM. In two cases, partner clones had different VDJ rearrangements, with one clonotypic signature in bone marrow and a second in blood. For both cases, the bone marrow clone was hypermutated, whereas the blood clone was germ line or minimally mutated. In two other cases, partner clones shared a common VDJ rearrangement but had different patterns of somatic mutations. They lacked intraclonal diversity and were more abundant in bone marrow than in blood. VDJ mutation profiles suggested they arose from a common IgM progenitor. Single-cell analysis in one case indicated the partner clones were reciprocally expressed, following rules of allelic exclusion. CONCLUSIONS: The existence of two B-cell clones having distinct VDJ sequences is common in WM, suggesting that frequent transformation events may occur. In two cases, the partner clones had distinct tissue distributions in either blood or bone marrow, were of different immunoglobulin isotypes, and in one case exhibited differential response to therapy. The contributions of each clone are unknown. Their presence suggests that WM may involve a background of molecular and cellular events leading to emergence of one or more malignant clones.  相似文献   
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