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71.
M. BJØRGAAS K. AASARØD 《Scandinavian journal of clinical and laboratory investigation》2013,73(3):233-238
The purpose of this study was to investigate the circulatory responses to hypoglycaemia in diabetic and non‐diabetic children and to determine whether these changes were associated with hormone levels or clinical variables. Plasma glucose levels in 18 diabetic and 15 control children were gradually lowered to 2.5 (0.3)?mmol/L (mean (SD)) and 2.9 (0.2)?mmol/L, respectively. Blood pressure and heart rate were recorded at 10‐min intervals, and blood samples were taken for hormone analysis. Systolic pressure increased from 110.1 (10.0) to 115.0 (11.2)?mmHg (p=0.008) in the diabetic children and from 116.9 (12.0) to 121.6 (12.7)?mmHg (p=0.049) in the controls. Diastolic pressure decreased from 61.9 (6.7) to 55.5 (7.6)?mmHg (p<0.001) in the diabetic children and from 66.5 (6.3) to 55.1 (5.1)?mmHg (p<0.001) in the controls. The increase in pulse pressure during hypoglycaemia was significantly smaller in the diabetic children (10.6 (5.5) vs. 15.7 (7.7)?mmHg, p=0.04). The final systolic and pulse pressure correlated with the final adrenaline level in the controls (r=0.66, p=0.008 and r=0.70, p=0.003, respectively). In the non‐diabetic as well as the diabetic group, the increase in pulse pressure correlated with the increase in adrenaline (r=0.66, p=0.008 and r=0.50, p=0.03, respectively). It is concluded that systolic pressure increases and diastolic pressure decreases during hypoglycaemia in children. The smaller increase in pulse pressure observed in the diabetic children is probably related to a significantly smaller increase in adrenaline in this group. 相似文献
72.
During computed tomography (CT) pelvimetry of two pregnant women, bony abnormalities of the fetuses were noted on the scout images that were not confirmed at delivery. To explore the cause of these artifacts, specimen long bones were manipulated in various ways during CT scout imaging. Artifacts like those seen during in vivo imaging were found to be caused by motion of the object. The CT scout view is an example of an image produced by a digital system that uses a scanning beam. This type of digital system is being used for several types of body imaging including screening for scoliosis and chest radiography. Attention to motion artifacts should decrease diagnostic errors and aid further development of these systems. 相似文献
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Christine C Lieggi Jeffrey D Fortman Robert A Kleps Varun Sethi John A Anderson Charles E Brown James E Artwohl 《Contemporary topics in laboratory animal science》2005,44(1):11-16
This reports the in vitro portion of a study designed to establish guidelines for the preparation, storage, and use of tribromoethanol (TBE). We evaluated: 1) the purity of TBE powder from three suppliers; 2) nine methods of preparation of a 25-mg/ml (working) solution for formation of particulates and breakdown products; 3) formation of particulates and breakdown products and pH change in 1-g/ml (stock) solutions and working solutions stored under four conditions (25 degrees C and 5 degrees C in light and in dark); and 4) stock and working solutions of TBE that caused lethal effects in mice. These objectives were met by using nuclear magnetic resonance spectroscopy, gas chromatography-mass spectroscopy, particle-size and turbidity analyses, and pH strips. TBE powder from three suppliers varied in purity. No significant differences in breakdown product formation, particle size, or turbidity were noted between the nine preparation methods evaluated. Stock solutions and the working solution stored at 5 degrees C in the dark maintained a pH of 6.5 to 7.0, whereas the pH dropped for all other working solutions. A low level of dibromoacetaldehyde (DBA), a potential breakdown product reported to cause toxic effects, was detectable in all newly prepared solutions. Regardless of the storage condition or pH, DBA concentration did not increase measurably in any of the solutions after 8 weeks. The stock and working solutions that demonstrated lethal effects in mice had a pH of 6.5 and did not differ notably from newly prepared, non-lethal solutions, when evaluated for DBA. A decrease in pH could not be correlated to an increase in DBA or potential lethality, as suggested in the literature. The toxicity associated with the lethal TBE in this study appears to be a result of a chemical reaction or breakdown product that has not yet been reported. 相似文献
75.
Many questions about analgesic nephropathy (AN) lack clear-cut answers. We present available evidence for and against proposed answers to many of these questions. These include: (1) Is acetaminophen (AC) nephrotoxic when taken as the sole analgesic? (2) Is the combination of acetylsalicylic acid (ASA) and AC more nephrotoxic than AC taken alone, and if so, why? (3) What are the minimum doses and durations of ingestion required to produce analgesic nephrotoxicity? (4) Is the combination of ASA and AC (a major metabolite of phenacetin) less nephrotoxic than that of phenacetin and ASA combined? (5) Does caffeine in combination with analgesics contribute to nephrotoxicity? (6) What is the incidence of end-stage renal disease (ESRD) due to AN? (7) What uniform diagnostic criteria should be established for AN? (8) What are the earliest anatomic and biochemical abnormalities? (9) What are the mechanisms of renal injury? (10) Does AC cause uroepithelial neoplasia? (11) What research might be most beneficial? Based mainly on associations, some strong, we suggest that AN still exists as a cause of ESRD in the United States, where AC/ASA combinations are available over the counter, and in Canada, where they are not. We also suggest that the evidence needed to recommend that the AC/ASA combination be excluded from over-the-counter analgesic preparations still has limitations. A prospective multicenter study comparing incidence related to AC/ASA in the United States and to AC in Canada and the United States may be needed to answer this question. For such a study to be worthwhile, an adequate incidence in both countries is required. 相似文献
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A screening program of 10,040 cigarette-smoking men over 45 years of age was undertaken in an attempt to achieve earlier diagnosis, thereby increasing the cure rate, of oat cell lung cancer. Of the 155 men who were found to have lung cancer, 27 (17%) had confirmed oat cell cancer. Only one case was diagnosed at the first examination. The other 26 cases (called incidence cancer) were diagnosed by subsequent examinations. In 24 of the 26 patients, the tumor was not found until it was advanced (Stage III), and of these patients, only one is alive at 21 months follow-up. Two tumors were diagnosed as oat cell carcinoma at an early stage (Stage I), and both patients are alive with no evidence of disease at seven and 24 months. The screening program used in this study did not succeed in detecting oat cell cancer at an early stage. 相似文献
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