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21.
It has been shown both in type I and in type 2 diabetes that optimal glucose control retards the development of diabetes-related complications. The concentration of glycated haemoglobin (HbA1c) is a measure of metabolic control during the previous five weeks. Several studies have indicated that an elevated blood glucose level after an oral glucose tolerance test or after a meal (2-hour value: 7-11 mmol/l) is a better risk indicator for future cardiovascular disease and death than the level of fasting blood glucose or HbA1c. Increased glucose auto-oxidation, labile glycosylation and intracellular activation of the polyol pathway leading to increased oxidative stress are believed to play an important pathophysiological role. In addition, direct stimulatory effects of glucose on specific intracellular signalling peptides, such as protein kinase C, as well as a direct effect on the vessel walls also play a role. In future studies the challenge will be to demonstrate the specific effects of improved postprandial blood-glucose control, and to separate these out from the general effects of intensive therapy with oral medication and insulin on glucose control. People suffering from diabetes are best advised to direct their self control also at the bloodglucose level 1.5-2 h after a meal.  相似文献   
22.
Measurement of urinary flow rate using ultrasound in young boys and infants   总被引:2,自引:0,他引:2  
PURPOSE: We present a technique for measuring urinary flow rates with ultrasound in male infants and children. MATERIALS AND METHODS: Urinary flow rate was measured simultaneously by an ultrasound probe placed around the base of the penis and by a funnel with a rotating disk at the bottom in 30 boys with a mean age of 6.7 years (range 4.5 to 10.5), and by ultrasound in 8 infants with a mean age of 10 months (range 1 to 28). Voided volume was measured with a graded cylinder or calculated from the weight change of diapers in infants. Ultrasound and rotating disk maximum flow rates were calculated. The ultrasound signal was calibrated by comparing the collected voided volume to the area under the curve for that void. The volume calculated from the rotating disk flow rate curve was also compared with the collected volume. RESULTS: Both methods yielded similar flow curves. However, ultrasound maximum flow rate significantly exceeded rotating disk maximum flow rate (13 +/- 6 ml. per second, range 5 to 22 versus 10 +/- 4 ml. per second, range 4 to 21, t test p <0.001). The underestimation of the flow rate by the rotating disk method may have been due to adherence of urine to the funnel wall. Rotating disk maximum flow rate was lower and voided volume was underestimated by up to 50% (average 15 +/- 2%) in 21 cases. Ultrasound maximum flow rate averaged 6 +/- 3 ml. per second (range 3 to 11.6 [oldest infant]) in the 8 infants. CONCLUSIONS: Urinary flow rates can be measured accurately using ultrasound in boys who produce small volumes and/or who are not toilet trained and also in infants. In future studies ultrasound will be applied to subsets of male infants with bladder dysfunction.  相似文献   
23.
BH Newman  ; DA Waxman 《Transfusion》1996,36(3):213-215
BACKGROUND: There is little information in the medical literature on t he clinical spectrum of blood donation-related neurologic needle injury and on its frequency in a blood donor population. STUDY DESIGN AND METHODS: Sixty-six cases of blood donation-related neurologic needle injury were identified from nursing reports made during a 2-year collection period involving 419,000 whole blood donations. Telephone follow-up was completed on 56 of the 66 cases to better define clinical symptoms, the donor's desire for physician consultation, recovery times, and residual effects. RESULTS: Symptoms in 66 donors included numbness or tingling (n = 54), excessive or radiating pain (n = 43), and loss of arm or hand strength (n = 8). Of the 56 donors with complete follow-up, 17 (30%) consulted a physician one or more times. Recovery times in these 56 donors were <3 days (n = 22), 4 to 29 days (n = 17), 1 to 3 months (n = 13) 3 to 6 months (n = 2), and >6 months (n = 2). Fifty-two of 56 donors achieved a full recovery, and 4 other donors had only a mild, localized, residual numbness. The incidence of blood donation-related neurologic needle injury was 1 of every 6300 donations. CONCLUSION: While donor recovery may in some cases require a great deal of time and/or physician consultation(s), total recovery appears to be the rule. The incidence of blood donation-related neurologic needle injury is relatively low.  相似文献   
24.
In a 57-year-old man with symptomatic hypoglycaemias which gave cause to suspect an insulinoma, normal insulin levels were initially found. A repeated fasting assay at another hospital did, however, reveal the expected hyperinsulinaemia. Scans revealed an abnormality in the pancreas. After surgical removal of the insulin-producing tumour the patient made a quick recovery. The diagnosis of organic hyperinsulinaemia is established by demonstrating inappropriately high serum-insulin concentrations during fasting hypoglycaemia. The diagnostic normative values are based on the classic polyclonal method of determination. This new highly-specific insulin assay has no cross-reactivity with pro-insulin, which is often produced disproportionately more by an insulinoma. As a result of this false-normal insulin values are found. Therefore new normative values are needed for the newer insulin assays when diagnosing an insulin-producing islet cell tumour. Pro-insulin and C-peptide assays may play a useful role in this.  相似文献   
25.
OBJECTIVE: To assess the quality of hypertension care in patients with type 2 diabetes in general practice and identify physician, organizational, and patient factors associated with suboptimal care. RESEARCH DESIGN AND METHODS: Data from 895 randomly selected diabetic patients were extracted from the electronic medical records of 95 general practitioners. Physician and organizational characteristics were collected with a questionnaire. We conducted a multilevel analysis to identify associations with blood pressure registration, hypertension treatment, and achievement of target blood pressure levels. RESULTS: For 652 patients (73%), a blood pressure measurement was recorded in the last year. Of these patients, 132 (20%) reached a target level of 135/85 mmHg. In total, 595 patients were classified as having hypertension, of whom 192 received no treatment (32%), 193 received an ACE inhibitor (32%), and 210 received other antihypertensives. Patients visiting a diabetes facility, referred to a specialist, with a female general practitioner, or with a general practitioner with 相似文献   
26.
The data of the present case demonstrate that the abuse of androgenic anabolic steroids (AAS) may lead to serious health effects. Although most clinical attention is usually directed towards peripheral side effects, the most serious central side effect, hypothalamic-pituitary-dysfunction, is often overlooked in severe cases. Although this latter central side-effect usually recovers spontaneously when AAS intake is discontinued, the present case shows that spontaneous recovery does not always take place. We suggest that hypothalamic-pituitary dysfunction should always be considered in the differential diagnosis in athletes seen with typical presentation of anabolic steroid use. In order to regain normal hypothalamic-pituitary function, supraphysiological doses of 200 microg LH-RH should be considered when the physiological challenge test with LH-RH (50 microg) fails to show an acceptable response.  相似文献   
27.
Two women aged 50 and 64 years, respectively, and one man aged 43 years, were treated with cyclic etidronic acid for osteoporosis. After some months/years they developed mood, concentration and memory problems. The complaints diminished within several weeks after withdrawal of the drugs, and reappeared after rechallenge. Two of these patients had similar complaints during the use of another bisphosphonate (pamidronic acid and alendronic acid, respectively). Bisphosphonates are used increasingly frequently for the treatment of osteoporosis. Generally, these drugs are well tolerated. The most frequently reported adverse events are gastrointestinal complaints and oesophageal ulcers. Psychiatric complaints also appear to be a rare side effect.  相似文献   
28.
Rosiglitazone     
Type 2 diabetes mellitus is characterised by impaired insulin secretion, diminished peripheral insulin action and increased hepatic glucose production. Clinical trials have indicated that near-normal glucose control may reduce the risk for microvascular and - to a lesser extent - macrovascular complications in Type 2 diabetic patients. Thiazolidinediones improve insulin action by activating a nuclear receptor, PPARgamma. Therefore, these drugs are often referred to as 'insulin sensitisers'. Rosiglitazone is the second compound of this group. Clinical studies with rosiglitazone have shown that it is effective in lowering blood glucose levels in Type 2 diabetic patients treated with either diet alone, sulphonylurea or metformin. Preliminary studies suggest that rosiglitazone also improves glycaemic control in insulin-treated patients while even slightly decreasing insulin dose. The magnitude of the effects is, however, moderate. In diet-treated patients, the reduction of HbA1c levels amounted on average 0.5 - 1.5% and addition to existing sulphonylurea therapy decreased HbA1c by 1.0 - 1.2%. The clinical relevance of additional beneficial effects, i.e., on blood pressure and microalbuminuria, needs to be determined further. Rosiglitazone does not cause hypoglycaemia or gastrointestinal side effects. There is however some concern related to fluid retention, which seems to be an effect of all PPARgamma agonists. In patients treated with rosiglitazone, no severe hepatotoxic side effects have been noticed until now. In the treatment of our patients with Type 2 diabetes, drugs like rosiglitazone which directly reduce insulin resistance are very welcome but more data on its combined use with insulin are needed. Additional studies will also explore its long-term effects in sparing beta-cell function and reducing diabetes-related complications and atherosclerosis.  相似文献   
29.
Digital beam attenuator technique for compensated chest radiography   总被引:1,自引:0,他引:1  
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.  相似文献   
30.
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