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991.
Cochlear implants are no longer considered new or experimental technology. Difficulty in evaluating the degree of hearing loss and response to traditional forms of amplification in young children makes pediatric cochlear implant candidacy a complex issue. Cochlear implantation and, in particular, pediatric cochlear implantation, requires a team commitment with contributions from surgeons, audiologists, speech pathologists, psychologists, and special educators. Elements discussed include assessment and candidacy issues, surgical technique, elements of a cochlear implant team, outcome assessment, and potential complications. The decision to perform pediatric cochlear implantation should not be undertaken without serious consideration to the enormous commitment required in both financial and personnel terms. 相似文献
992.
CM Law DJ Barker WW Richardson AW Shiell LP Grime NG Armand-Smith AM Cruddas 《Canadian Metallurgical Quarterly》1993,47(4):255-259
OBJECTIVE: To determine whether babies in an area of Britain with unusually high perinatal mortality have different patterns of fetal growth to those born elsewhere in the country. DESIGN: Measurement of body size in newborn babies. SETTING: Burnley (perinatal mortality in 1988 15.9/1000 total births) and Salisbury (perinatal mortality 10.8/1000 total births), England. SUBJECTS: Subjects comprised 1544 babies born in Burnley, Pendle, and Rossendale Health District, and 1025 babies born in Salisbury Health District. MAIN OUTCOME MEASURES: Birthweight, length, head, arm and abdominal circumferences, and placental weight were determined. RESULTS: Compared with babies born in Salisbury, Burnley babies had lower mean birthweight (difference 116 g, 95% confidence interval (CI) 77,154), smaller head circumferences (difference 0.3 cm, 95% CI 0.2, 0.4), and were thinner as measured by arm circumference (difference 0.3 cm, 95% CI 0.3, 0.4), abdominal circumference (difference 0.5 cm, 95% CI 0.4, 0.6) and ponderal index (difference 0.8 kg/m3, 95% CI 0.6, 1.0). The ratio of placental weight to birthweight was higher in Burnley (difference 0.6%, 95% CI 0.4, 0.9). These differences were found in boys and girls and did not depend on differences in duration of gestation or on the different ethnic mix of the two districts. Mothers in Burnley were younger, shorter in stature, had had more children, were of lower social class, and more of them smoked during pregnancy than mothers in Salisbury. These differences did not explain the greater thinness of their babies. CONCLUSIONS: Babies born in Burnley, an area with high perinatal mortality, are thin. The reason is unknown. Poor maternal nutrition is suspected because Burnley babies have a higher ratio of placental weight to birthweight. The greater thinness at birth of Burnley babies could have long term consequences, including higher rates of cardiovascular disease. 相似文献
993.
We report the case of a 72-year-old male patient who developed a florid photosensitive eruption while on ranitidine therapy. Ultraviolet A sensitivity was detected by irradiation monochromator testing, suggesting drug-induced photosensitivity. Ranitidine was concluded to be the cause of his photosensitivity since the eruption resolved and the phototest abnormalities returned to normal following cessation of therapy. Similar cases have been reported to the Committee on Safety of Medicines but not published. 相似文献
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996.
Previous studies have shown that the prostaglandin synthesis inhibitor indomethacin reduced osteolysis produced by the experimental VX2 carcinoma, probably by inhibiting the stimulation of osteoclasts by prostaglandin E2. This study was carried out to determine whether prostaglandin inhibitors affect the tumour osteolysis produced by human mammary carcinoma as well as the VX2 carcinoma. The effect of diphosphonates on reducing tumour osteolysis was also investigated, since diphosphonates directly affect bone resorption. The results indicated that various non-steroidal, anti-inflammatory agents which inhibit prostaglandin synthesis reduced the osteolysis produced by human mammary or rabbit VX2 carcinomas. The diphosphonate compounds also produced a significant inhibition of tumour osteolysis. The results confirm the findings of Powles and his colleagues (1) that aspirin (also a prostaglandin synthesis inhibitor) reduced the osteolysis induced by human mammary carcinoma. It is suggested that these agents be evaluated as adjuvant therapy in patients with apparently 'early' mammary cancer in a controlled clinical trial. 相似文献
997.
AW Dellipiani EL Cay AE Philip NJ Vetter WA Colling RJ Donaldson P McCormack 《Canadian Metallurgical Quarterly》1976,38(7):752-757
An objective measurement of anxiety at defined intervals after the onset of acute cardiac symptoms was made in 203 men admitted to the Coronary Care Unit, Royal Infirmary of Edinburgh, and in 83 patients in a Teesside coronary survey. Of the Teesside patients, 50 were treated at home, 22 were admitted initially to a coronary care unit, and 11 were admitted directly to a general medical ward. In the Edinburgh patients the level of anxiety was high early in the illness, fell rapidly, and rose again towards the end of their stay in hospital. At 4 months it was that of a normal population. After transfer from the coronary care unit the group was not more anxious than other patients in the ward. Reaction to the illness was unrelated to its physical severity. Patients who reacted badly at the beginning were less likely to return to work. The pattern of anxiety in the Teesside patients resembled that of the Edinburgh group, and reaction to illness was largely independent of physical aspects. Treatment in hospital, either through a coronary care unit initially or in a medical ward, did not increase emotional distress. At 3 months patients treated initially in a coronary care unit were less anxious than the others. Throughout the period of study the Teesside patients were more anxious than the Edinburgh patients and outcome was not related to anxiety. Social and environmental differences may account for this. 相似文献
998.
999.
W Levin AW Wood PG Wislocki J Kapitulnik H Yagi DM Jerina AH Conney 《Canadian Metallurgical Quarterly》1977,37(9):3356-3361
Benzo(a)pyrene (BP) and several benzo-ring derivatives of BP were tested for carcinogenic activity in mice by topical application of each compound once every 2 weeks for 60 weeks. Chronic treatment of C57BL/6J mice with (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene (0.025 to 0.10 micronmole/application) indicated that the dihydrodiol was slightly more active as a complete carcinogen than the parent hydrocarbon BP. 7,8-Dihydroxy-7,8,9,10-tetrahydro-benzo(a)pyrene, a compound related to (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene but which lacks the double bond at position 9,10, was inactive as a carcinogen on mouse skin. These results indicate the importance of the double bond at position 9,10 for the carcinogenic activity of (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene. Chronic treatment of mice with -.4 micronmole of the highly mutagenic (+/-)-7,beta,8alpha-dihydroxy-9alpha, 10alpha-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene, (+/-)-7beta,8alpha-dihydroxy-9beta, 10beta-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene, or 9,10-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene every 2 weeks for 60 weeks resulted in tumor incidences of 0, 8, and 4%, respectively, whereas BP at this dose caused a 100% tumor incidence. The high reactivity of the three epoxides may account for their inactivity or their weak carcinogenic activity on mouse skin. 相似文献
1000.