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11.
BA Cunningham PJ Quinn DH Wolfe W Tamura-Lis LJ Lis O Kucuk MP Westerman 《Canadian Metallurgical Quarterly》1995,1233(1):68-74
A questionnaire survey was carried out to examine the attitudes and practices of Australian and New Zealand intensivists with regard to brain death and organ donation. A return rate of 82.5% was achieved. Fifty-eight per cent had written evidence of their own wishes to donate organs and 94% would agree to donation from a dependent. At least one intensivist is involved in certifying brain death on 95% of occasions. Intensivists are involved in the request for organ donation over 90% of the time although one-third do not believe that it is their role to request organ donation. Although two-thirds believe that the family should always be approached for organ donation, another 52 out of 254 indicated that it was their (the intensivist's) role to decide if families should be asked for organ donation. Possible reasons for not requesting are language or other communication problems, perceptions of cultural differences and degrees of family distress. Twenty per cent of respondents do not provide haemodynamic support before brain death confirmation. Australian and New Zealand intensivists overwhelmingly support the concept of brain death, current methods of confirmation of brain death, organ donation and transplantation. Possible reasons behind loss of potential donors include decisions not to resuscitate both before and after brain death is confirmed. Perceptions of family grief and cultural differences clearly inhibit requests for organ donation. A very few units have an effective policy on approaching families about organ donation. Intensivists have almost exclusive control over requests for organ donation and thus bear a full professional responsibility for this element of hospital practice. 相似文献
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Arylsulfate sulfotransferase purified from Eubacterium A-44 has higher specific activity than the enzymes from Klebsiella K-36 and Haemophilus K-12. Propylparaben and butylparaben were good substrates among several parabens. The antibacterial activity of parabens was reduced by the sulfation of the phenolic hydroxy group. Tyrosine-containing peptides, kyotorphin, enkephalin and cholecystokinin non-sulfate, were effective as acceptor substrates by A-44, K-36 and K-12 sulfotransferases. 相似文献
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STUDY DESIGN: This study retrospectively reviewed the intermediate-term clinical outcome of patients who were 50 years of age or older at the time they experienced their cervical spinal cord injury. OBJECTIVES: To establish reasonable expectations for the functional outcome in the older patient with cervical spinal cord injury. BACKGROUND DATA: The long-term morbidity and mortality of large groups of patients with spinal cord injury have been reported. The specific functional ability, disposition, morbidity, and mortality of this group of older patients injured after 50 years of age, however, have been less well defined. METHODS: Forty-one consecutive patients older than 50 years of age at the time of cervical cord injury were studied, and functional abilities, independence, need for assistance in activities of daily living, disposition, morbidity, and mortality were assessed. All patients had more than 2 years of follow-up examinations (mean, 5.5 years) by the same spine injury service. RESULTS: There were 13 complete and 28 incomplete cervical cord lesions. The mean age of the patients at follow-up examination was 67.5 years. The average follow-up period was 5.5 years after injury. None of the patients with complete cord injury improved, and all required extensive care. Twenty-one (80%) of 26 of the patients with incomplete cord injury were able to ambulate with some assistance. Nineteen of 26 patients had independent or near-independent abilities with activities of daily living. Twenty (77%) of 26 were able to return home. All patients with complete cord injury (13 of 13) had died by the time of the follow-up visit. Seventy-seven percent (10 of 13) of this patient group had died within the first year. Those surviving lived an average of 3.5 years after their injury. Fourteen of 28 patients with incomplete cord injury (50%) had died by the time of the follow-up visit. Six (43%) of the 14 deaths were attributed to complications of their spinal cord injury. CONCLUSION: The functional outcome of the person older than 50 years with a complete cervical cord injury is poor. Of the 14% who survived the first year, all required extensive attendant care, and no neurologic improvement was seen. The patient with an incomplete cord injury has an overall good outcome regarding ambulation and returning to home. 相似文献
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For complex genetic diseases involving incomplete penetrance, genetic heterogeneity, and multiple disease genes, it is often difficult to determine the molecular variant(s) responsible for the disease pathogenesis. Linkage and association studies may help identify genetic regions and molecular variants suspected of being directly responsible for disease predisposition or protection, but, especially for complex diseases, they are less useful for determining when a predisposing molecular variant has been identified. In this paper, we expand upon the simple concept that if a genetic factor predisposing to disease has been fully identified, then a parent homozygous for this factor should transmit either of his/her copies at random to any affected children. Closely linked markers are used to determine identity by descent values in affected sib pairs from a parent homozygous for a putative disease predisposing factor. The expected deviation of haplotype sharing from 50%, when not all haplotypes carrying this factor are in fact equally predisposing, has been algebraically determined for a single locus general disease model. Equations to determine expected sharing for multiple disease alleles or multiple disease locus models have been formulated. The recessive case is in practice limiting and therefore can be used to estimate the maximum proportion of putative susceptibility haplotypes which are in fact predisposing to disease when the mode of inheritance of a disease is unknown. This method has been applied to 27 DR3/DR3 parents and 50 DR4/DR4 parents who have at least 2 children affected with insulin dependent diabetes mellitus (IDDM). The transmission of both DR3 and DR4 haplotypes is statistically different from 50% (P < 0.05 and P < 0.001, respectively). An upper estimate for the proportion of DR3 haplotypes associated with a high IDDM susceptibility is 49%, and for DR4 haplotypes 38%. Our results show that the joint presence of non-Asp at DQ beta position 57 and Arg at DQ alpha position 52, which has been proposed as a strong IDDM predisposing factor, is insufficient to explain the HLA component of IDDM predisposition. 相似文献
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The shear bond strengths of the XR-Bonding System used in conjunction with Herculite composite, to the dentine of forty extracted human permanent first and second molars were determined after the test specimens were stored in physiological saline at 37 degrees C for 48 hours, one week, two weeks and four weeks, respectively. A shear load was applied to the base of the bonded composite cylinders with a knife-edged rod at a crosshead speed of 0.5 mm/minute. The shear bond strengths were expressed in megapascals (MPa). The quantitative microleakage of Class V preparations in dentine (cementum) in forty-eight extracted human maxillary permanent canines restored with the same dentinal bonding system and after storage in physiological saline at 37 degrees C for the same time intervals as for the shear bond strength tests, was determined. On the final day of each time interval the teeth were thermocycled X 500 in a 2 per cent methylene blue solution between 8 degrees C and 50 degrees C with a dwell time of 15 seconds. Microleakage was determined by a spectrophotometric dye-recovery method and expressed in microgram dye/restoration. There was a significant trend for the shear bond strengths to increase with duration of storage (p = 0.01) but the quantitative microleakage was not significantly different (p = 0.75). 相似文献
18.
Tellegen Auke; Lykken David T.; Bouchard Thomas J.; Wilcox Kimerly J.; Segal Nancy L.; Rich Stephen 《Canadian Metallurgical Quarterly》1988,54(6):1031
We administered the Multidimensional Personality Questionnaire (MPQ) to 217 monozygotic and 114 dizygotic reared-together adult twin pairs and 44 monozygotic reared-apart adult twin pairs. A four-parameter biometric model (incorporating genetic, additive versus nonadditive, shared family-environment, and unshared environment components) and five reduced models were fitted through maximum-likelihood techniques to data obtained with the 11 primary MPQ scales and its 3 higher order scales. Solely environmental models did not fit any of the scales. Although the other reduced models, including the simple additive model, did fit many of the scales, only the full model provided a satisfactory fit for all scales. Heritabilities estimated by the full model ranged from .39 to .58. Consistent with previous reports, but contrary to widely held beliefs, the overall contribution of a common family-environment component was small and negligible for all but 2 of the 14 personality measures. Evidence of significant nonadditive genetic effects, possibly emergenic (epistatic) in nature, was obtained for 3 of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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