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131.
Carbamazepine and vigabatrin are contraindicated in typical absence seizures. Of 18 consecutive referrals of children with resistant typical absences only, eight were erroneously treated with carbamazepine either as monotherapy or as an add-on. Vigabatrin was also used in the treatment of two children. Frequency of absences increased in four children treated with carbamazepine and two of these developed myoclonic jerks, which resolved on withdrawal of carbamazepine. Absences were aggravated in both cases where vigabatrin was added on to concurrent treatment. Optimal control of the absences was achieved with sodium valproate, lamotrigine, or ethosuximide alone or in combination.  相似文献   
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Purpose: To establish the prevalence and severity of myopia among the Chinese Hong Kong students and to study the relationship between myopia and optical components.Methods;One thousand and seventy-five freshmen of the 1993-1994 academic year in the Chinese University of Hong Kong underwent the eye examination including evaluation of refractive error, keratometry, and A-scan ultrasonic biometry. The data were analyzed with the SPSS/PC 4. 01 statistical package. Results: The prevalence of myopia was 91. 7% with the mean refraction being -4. 00 ± 2. 64D in this young adult population. The statistical analyses demonstrated a significant correlation between refractive value and axial length of the globe (r=-0. 78), vitreous length (r=-0. 76), anterior chamber depth (r=-0. 33), lens thickness (r = 0. 13) and corneal curvature (r = 0. 19). Conclusion: The refractive status is mainly dependent on the axial length. In general, the higher the myopia was, the longer the eyeball, the deeper the anterior chamber,  相似文献   
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After storage at 4 C for 20 to 28 days, red blood cells were biochemically modified to improve their oxygen transport function which had deteriorated during liquid storage. The solution used for rejuvenation contained pyruvate, inosine, glucose, phosphate, and adenine (PIGPA Solution B). The rejuvenated red blood cells were frozen with 40% W/V glycerol in a polyolefin plastic bag and were stored in the frozen state for about 1.5 years at −80 C. After thawing and washing the red blood cells were stored at 4 C in a sodium chloride- glucose-phosphate solution for 24 hours before transfusion. A pool of four to ten units was rapidly transfused to each of 14 elderly anemic recipients, 11 of whom had cardiopulmonary insufficiency. Recovery of the red blood cells after the freeze-thaw process was about 97 per cent, and after the freeze-thaw-wash process about 90 per cent. The 24− hour posttransfusion survival values were about 75 per cent, and the long-term survival values were about 85 days depending on the disease state of the recipient. The red blood cells had 1.5 times normal 2.3- DPG levels and a decreased affinity for oxygen at the time of transfusion and were able to delivery oxygen at high oxygen tension immediately after the rapid infusion of pools of from four to ten units through a 40-or 170-micron filter. Plasma hemoglobin levels were consistent with extravascular sequestration of nonviable red blood cells, and uric acid levels were not increased during the immediate 24− hour posttransfusion period.  相似文献   
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Although several hypotheses have been suggested regarding the accumulation of 99Tc(m)-sestamibi in tumours, the exact uptake mechanism is still a matter of discussion. We investigated ultrastructural cell type of thyroid tumours by electron microscopy (EM) and compared them with uptake of 99Tc(m)-sestamibi. Thyroid scintigraphy with 99Tc(m)-sestamibi was performed on 25 patients who displayed a cold nodule on previous pertechnetate scintigraphy. Tumour-to-thyroid (T/N) uptake ratio was measured semiquantitatively. Surgery was performed in all patients and cytological evaluations were done by EM. Histopathology revealed six papillary carcinomas, 16 follicular adenomas and three Hurthle cell tumours. Thyroid cells were classified as A and B cells using EM. The cytoplasm of an A cell has the normal amount of mitochondria, whereas cytoplasm of a B cell (mitochondria-rich oxyphilic cell) contains abundant mitochondria. The median T/N ratio on the early scan for an A-cell tumour was 1.21 (range, 0.74-3.2), late T/N ratio was 1.25 (range, 0.72-3.85). The T/N ratio for the B-cell tumours was 1.42 (range, 0.6-3.6) on the early scan and 1.18 (range, 0.64-5.58) on the late scan. There was no statistically significant difference between T/N ratios of A- and B-cell tumour groups. A significant difference was also not seen between early and late T/N ratios. According to our findings, 99Tc(m)-sestamibi accumulates in thyroid tumours with both A and B cells, therefore these results suggest that the mitochondrial content of tumours is not only responsible for sestamibi uptake and retention.  相似文献   
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