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L-Ascorbic acid (Vitamin C) produced a marked reduction in the blood glucose concentration following intravenous injection (20-100 mg kg-1) to anaesthetized rats. This hypoglycaemic effect was accompanied by an increase in plasma insulin concentration. D-ascorbic acid produced a similar hypoglycaemic effect.  相似文献   
44.
Winkler  ML; Olsen  WL; Mills  TC; Kaufman  L 《Radiology》1987,165(1):203-207
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study.  相似文献   
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PURPOSE: To study the diagnostic ability of scanning laser polarimetry with variable corneal compensation (GDx VCC) for early glaucomatous (EG) eyes and glaucoma-suspect (GS) eyes in a Taiwan Chinese population. METHODS: This prospective cross-sectional study included 82 EG eyes (mean deviation, MD: -3.32 +/- 2.20 dB), 45 GS eyes (MD: -2.43 +/- 2.16 dB), and 62 normal eyes. Retinal nerve fiber layer thickness of each subject was measured using GDx VCC and Humphrey Field Analyzer visual field testing. Measured GDx VCC parameters were compared among groups. The area under the receiver operating characteristic (AROC) curve of each parameter was used to differentiate normal from EG eyes or GS eyes. The correlation between MD and each parameter was also evaluated. RESULTS: For both normal versus EG and normal versus GS, the largest AROC values were for nerve fiber indicator, superior average thickness, and inferior average thickness. There was no significant correlation between MD and GDx-VCC-measured parameters either in EG or GS eyes. CONCLUSIONS: GDx VCC shows only moderate ability to distinguish normal eyes from eyes with early glaucoma. However, its diagnostic role in eyes with suspicious discs and normal visual fields is uncertain at this moment in the Taiwan Chinese population. Further studies are needed to address this issue.  相似文献   
47.
Y H Tsai  M H Chang 《台湾医志》1992,91(3):283-286
Fasting serum gastrin values were measured by radioimmunoassay in 53 children with peptic ulcer disease. The mean fasting serum gastrin levels for children with chronic duodenal ulcer, acute gastric ulcer, acute duodenal ulcer who were younger than two years old and acute duodenal ulcer who were older than two years old were: 46.2 +/- 25.7 pg/mL, 46.9 +/- 43.5 pg/mL, 47.9 +/- 12.0 pg/mL and 37.5 +/- 17.8 pg/mL, respectively. Children with peptic ulcer disease did not have elevated fasting serum gastrin levels when compared with age-matched controls. We conclude that a fasting serum gastrin value cannot be used as a screening test for peptic ulcer disease in children, except for Zollinger-Ellison syndrome.  相似文献   
48.
The effect of inclination of the distal radius to subsequent lunate collapse is controversial. Therefore we evaluated the postoperative x-ray course of 10 patients with stage II, III, or IV Kienb?ck's disease who were treated only with radial shortening and followed up for an average of 25 months. The three patients who became worse as determined by x-ray evaluation had lunate fossa inclinations of less than 12 degrees after surgery. The four patients who improved had lunate fossa inclinations greater than 12 degrees. Appropriate radial shortening with adjunct wedge osteotomy to increase lunate fossa inclination may prevent further lunate collapse.  相似文献   
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Although cold syrup containing dextromethorpan bromide is widely administered, the bromism due to cold syrup has not been reported. We report a patient who had negative anion gap with hyperchloremia and conscious loss because of daily intake of cold complex syrup (containing dextromethorphan bromide 0.4 mg/ml, acetaminophen 8.33 mg/ml) for headache for 4-5 years. The bromide content in cold complex syrup resulted in serum levels of bromide that interfered with the automated analyzers for chloride content. When conscious change is due to bromism, hemodialysis instead of forced hydration and diuresis should be performed immediately. Therefore, patients with a markedly negative anion gap with hyperchloremia should be considered as having halide intoxication.  相似文献   
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