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81.
Manifestations and treatment of 793 cases of decompression sickness in a compressed air tunneling project in Hong Kong 总被引:1,自引:0,他引:1
In the largest compressed air tunneling contract for the construction of the Island Line of the Mass Transit Railway system in Hong Kong, 154,390 man-decompressions occurred, of which 142,140 were after exposures to 1 bar (1.97 ATA, 14.7 psig) or above. The maximum working pressure (MWP) was 3.30 bar (4.26 ATA, 47.9 psig). There were 792 cases of type I and 1 case of type II decompression sickness. The manifestations of the cases were generally similar to those reported elsewhere. Oxygen treatment was given to 9 cases and all were successfully treated with no recurrence of symptoms. Minimum effective pressure treatment on 783 type I cases was successful, with 9.6% requiring two or more recompressions. The pressure required to relieve symptoms was more closely related to the interval between completion of decompression after work and commencement of treatment than to the delay between onset of symptoms and treatment. For every 1-h interval or every 1-h delay, an additional pressure of 0.04 bar (0.04 ATA, 0.58 psi) above MWP was required for pain relief. Step-wise multiple regression analysis showed that the four predictors for pressure of relief and the highest pressure used in recompression, respectively, were, in order of descending importance, maximum working pressure, interval before treatment, bends sequence (the nth attack of bends experienced in the present contract, i.e., the sum of previous attacks and the present attack), and duration of exposure. 相似文献
82.
Efficacy of radical neck dissection for the control of cervical metastasis after radiotherapy for nasopharyngeal carcinoma 总被引:5,自引:0,他引:5
Fifty-one patients who had persistent or recurrent neck disease from nasopharyngeal carcinoma after radiotherapy underwent radical neck dissection. The follow-up period ranged from 0.5 to 9 years (median: 2 years). Multiple cervical lymph node involvement was present in 51% of the patients (26 of 51). Malignant cells were detected in 88% of the resected specimens (45 of 51). The clinical sign of fixation of lymph node is the only factor that affects the successful control of neck disease (p = 0.04). Extracapsular extension of the nodal disease was present, and 35% of the lymph nodes were adherent to surrounding structures at operation (18 of 51). There was one hospital mortality and the overall morbidity was minimal. The actuarial survival at 5 years was 38%, and the probability of control of neck disease was 66%. Radical neck dissection is effective in controlling post-irradiation cervical metastasis from nasopharyngeal carcinoma. 相似文献
83.
Elevation of prostaglandins and protein in the aqueous humor is an immediate response to Yag-laser anterior capsulotomy. There was a significant correlation between prostaglandins and thromboxane to the elevation of intraocular pressure. The elevation of protein concentration was proportional to the elevation of prostaglandin F1, but not to thromboxane. The biochemical changes in the aqueous humor were more severe as laser power was increased above 3 mj. While the role of prostaglandins in the elevation of intraocular pressure is uncertain, the present data recommend the selection of laser power below 3 mj to avoid pressure rise instead of inhibition of all prostaglandin synthesis by medication. 相似文献
84.
Preparation and evaluation of lectin-conjugated PLGA nanoparticles for oral delivery of thymopentin. 总被引:5,自引:0,他引:5
Yashu Yin Dawei Chen Mingxi Qiao Zhe Lu Haiyang Hu 《Journal of controlled release》2006,116(3):337-345
The purpose of this study was to design and evaluate lectin-conjugated PLGA nanoparticles for oral delivery of thymopentin. Thymopentin loaded PLGA nanoparticles (TP5-NPs) were prepared by a double emulsion-solvent evaporation technique. Novel WGA-PLGA conjugates were synthesized by coupling the amino groups of wheat germ agglutinin (WGA) to the carbodiimide-activated carboxylic groups of PLGA, and were incorporated into nanoparticles preparation to take mucoadhesive properties. Important characteristics such as particle size, zeta potential, entrapment efficiency, storage stability, as well as in vitro drug release behavior were investigated. The retention of biorecognitive activity of WGA after covalent coupling was confirmed by haemagglutination test. In vitro experiments with pig mucin (PM) demonstrated that the conjugation of WGA enhanced the interaction about 1.8-4.2 fold compared with that of the non-conjugated nanoparticles, and still exhibited sugar specificity. The pharmacodynamical studies on oral administration of WGA-TP5-NPs were performed in FACScan flow cytometry. The values of CD4(+)/CD8(+) ratios were significantly increased compared with that of TP5-NPs (p<0.01). The enhanced uptake was related to the increasing of WGA content on nanoparticles. These results confirmed that the conjugation of WGA onto PLGA nanoparticles effectively improved the intestinal absorption of TP5 due to specific bioadhesion on GI cell membrane. 相似文献
85.
86.
Andrew K. C. Lam Abby Lam Jessie Charm Kwai-mui Wong 《Ophthalmic & physiological optics》2005,25(2):162-167
PURPOSE: This study compared the near phoria measurement using the Bernell muscle balance card with and without prism neutralization, using both trial frame and phoropter correction, and compared with the conventional Maddox rod method. METHODS: Forty young normal Chinese adults had their near phoria measured with trial frame correction using the conventional muscle balance card method (method 1). Any deviation was compensated with a prism bar as an alternative approach (method 2). The conventional Maddox rod method (method 3) was also carried out for comparison. These three methods were repeated with phoropter correction and considered as methods 4, 5 and 6. RESULTS: The phorias obtained from these six methods were not significantly different from each other (repeated measures anova, p > 0.05). More than half of the subjects were exophoric. Although the difference in phoria was not significant, phoria measurement using phoropter correction yielded a greater coefficient of variation. CONCLUSIONS: Near phoria measurement using the muscle balance card conducted with trial frame correction was less variable, and was also more natural and similar to a real reading situation. The use of prism for compensation did not affect the phoria results. Exophoria seems to be more common than esophoria in young Chinese adults. 相似文献
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Siu Fai Li MD Nashat Latib MD Angela Kwong MD Shreni Zinzuwadia MD Ethan Cowan MD 《Academic emergency medicine》2007,14(12):1194-1196
Background In recent years, the number of women entering the field of emergency medicine (EM) has increased.
Objectives To determine if authorship in EM publications has increased in parallel with this trend.
Methods The gender of first and last authors of EM articles in Academic Emergency Medicine , American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine were examined. The authors reviewed articles from 1985, 1995, and 2005 for American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine and from 1999 and 2005 for Academic Emergency Medicine . The primary outcomes were the proportions of female authors.
Results A total of 2,016 articles were reviewed. Overall, 18% of first and last authors were female. Respectively, for 1985, 1995, 1999, and 2005, the proportions of female first authors were 9%, 15%, 19%, and 24%; the proportions of female last authors were 9%, 18%, 19%, and 22%. The trend of increases in female authorship was statistically significant.
Conclusions Although female authorship remains a minority in EM publications, it has increased significantly in parallel with increases in female participation in EM. 相似文献
Objectives To determine if authorship in EM publications has increased in parallel with this trend.
Methods The gender of first and last authors of EM articles in Academic Emergency Medicine , American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine were examined. The authors reviewed articles from 1985, 1995, and 2005 for American Journal of Emergency Medicine , Annals of Emergency Medicine , and Journal of Emergency Medicine and from 1999 and 2005 for Academic Emergency Medicine . The primary outcomes were the proportions of female authors.
Results A total of 2,016 articles were reviewed. Overall, 18% of first and last authors were female. Respectively, for 1985, 1995, 1999, and 2005, the proportions of female first authors were 9%, 15%, 19%, and 24%; the proportions of female last authors were 9%, 18%, 19%, and 22%. The trend of increases in female authorship was statistically significant.
Conclusions Although female authorship remains a minority in EM publications, it has increased significantly in parallel with increases in female participation in EM. 相似文献