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21.
Although mitochondrial aldehyde dehydrogenase (ALDH2) has been thought to play a major role in acetaldehyde detoxification, and the high incidence of 'alcohol flushing' among Orientals is attributed to the inherited deficiency of ALDH2, the role of cytosolic aldehyde dehydrogenase (ALDH1) cannot be ignored. On the premise that alcohol flushing in Caucasians could be related to ALDH1 abnormalities, we examined the enzyme properties and electrophoretic mobilities of ALDH1 partially purified from red blood cells of nine unrelated alcohol flushers. One exhibited very low activity (10–20% of control level), and another exhibited moderately low activity (60%) and altered kinetic properties. The electrophoretic mobilities of these two samples were also distinguishable from the control samples. Immunological quantitation indicated that the amounts of ALDH1 protein in these two samples were not reduced in parallel with their enzyme deficiency. In the first case, the two characteristics, i.e. very low enzyme activity and alcohol flushing, were inherited by her daughter. 相似文献
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Ward J M Videler Volkert B Wreesmann Freerk W van der Meulen Paul P Knegt Wytske J Fokkens 《Otolaryngology--head and neck surgery》2006,134(4):586-591
OBJECTIVES: Endoscopic sinus surgery (ESS) is considered to be the golden standard for surgery in patients with chronic rhinosinusitis and nasal polyposis. However, there is still a small group of patients unresponsive despite repetitive surgery. Radical surgery aimed at reduction of the inflammatory burden and optimization of drainage of the sinuses has been suggested as a last resort for these patients. STUDY DESIGN: A prospective, questionnaire-based study was conducted in a group of 23 patients who underwent Denker's procedure for refractory chronic rhinosinusitis. Symptoms were evaluated before Denker's procedure and 12 months and 2 years after surgery. RESULTS: Patients reported improvement of feelings of congestion in 74%, rhinorrhea in 70%, and nasal obstruction in 60% of the cases. The following postoperative improvements were statistically significant: rhinorrhea (P = 0.001), feelings of congestion (P = 0.02), and nasal obstruction (P = 0.03). Reduced olfactory perception and asthma did not improve. CONCLUSION: Radical surgery may be a viable treatment option in case of recurrent ESS failure. EBM rating: C-4. 相似文献
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Kathleen A. Ward Sinead A. McKernan Natalina N. Durnien Wallace W. Dinsmore 《Journal of the European Academy of Dermatology and Venereology》1995,4(2):160-165
Objective Detection of HPV DNA in oral and genital lesions of a heterosexual male. 4 months after oral and vaginal intercourse with a woman with vulvar warts. Passible modes of acquisition of oral HPV infection in the male sexual partner are discussed. Setting Genitourinary Medicine clinic. Methods Polymerase chain reaction amplification of genomic DNA from oral and genital lesions. HPV DNA typing by dot blot hybridization. Results HPV DNA types 6 and 11 were identified in a polypoid tongue lesion and in a penile wart from the male sexual partner. Conclusions The acquisition of oral HPV infection in the male sexual partner may have resulted from genital-oral HPV transfer, either by direct contact with vulvar warts or by digital self-inoculation. 相似文献
25.
Indications and results of relaxing retinotomy 总被引:8,自引:0,他引:8
The authors report their results of a consecutive series of 40 eyes undergoing relaxing retinotomy during vitrectomy to achieve retinal reattachment for the following indications: proliferative vitreoretinopathy (PVR), 21 eyes (52%); trauma, 10 eyes (25%); diabetic retinopathy, 6 eyes (15%); and expulsive choroidal hemorrhage, 3 eyes (8%). Thirty eyes (75%) had undergone previous vitreoretinal procedures. Extended tamponade was achieved in all cases with either silicone oil (27 eyes, 68%) or long-acting gas (13 eyes, 32%). Retinotomy size ranged from 45 degrees to 360 degrees. Intraoperative retinal attachment was possible in all eyes with 33 (83%) achieving total or subtotal retinal attachment including the macula for 5 months or more. Twenty-seven eyes (68%) achieved 3/200 visual acuity or better and 10 (37%) achieved 20/400 or better. Thirteen eyes (32%) failed to achieve 3/200 visual acuity secondary to recurrent detachment (18%), corneal decompensation (8%), macular dysfunction (5%), and glaucoma (3%). 相似文献
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The affinity of morphine, normorphine, methadone, Tyr-D-Ala-Gly-MePhe-NH(CH2)2(N-O)(CH3)2 (RX 783030), [D-Ala2,D-Leu5]enkephalin (DADLE), ketazocine and ethylketocyclazocine (EKC) were determined for their pharmacological receptors in two bioassay tissues, the guinea-pig ileum and the mouse vas deferens (MVD). The method involved the use of the irreversible antagonist, beta-chlornaltrexamine (beta-CNA), and the method of partial receptor blockade. The agonist concentration-effect curves were displaced to the right with decreasing maximum effect, a pattern typical of partial, irreversible blockade of receptors. The concentrations of beta-CNA required to produce a rightward displacement in the concentration-effect curves for different agonists, ranged between 2 and 3000 nM. No similarity was found between the IC50 and the dissociation constant (KA), values predicted to be equivalent only if a linear relationship exists between receptor occupation and observed effect; the dissociation constant for the agonists were between 3 and 218 times larger than the IC50 values. When methadone was used as the agonist in the guinea-pig ileum, beta-CNA produced parallel displacement of the concentration-effect curve, regardless of the blocking concentration chosen, preventing the determination of KA for this agonist, in this tissue; this problem was not encountered in the mouse vas deferens. The KA of morphine, RX 783030 and ketazocine were found not to differ in the guinea-pig ileum and mouse vas deferens. As expected, DADLE had significantly different affinity in the two tissues, showing 117-fold lower affinity in the guinea-pig ileum. Surprisingly, the normorphine affinity was found to be 7-fold higher in the guinea-pig ileum. While the difference in affinity of DADLE may be due to the suggested lack of functional delta receptors in the guinea-pig ileum, the difference in affinity seen with normorphine, but not morphine, in the two tissues is difficult to explain. Taken together with the insensitivity of methadone to beta-CNA blockade in the guinea-pig ileum, but not mouse vas deferens, the difference in the affinity of normorphine in these tissues may suggest the possibility of differences in local milieu of mu receptors or of mu receptor subtypes in the two tissues. The results provide fundamental information regarding opioid agonist affinity in two standard bioassays in vitro, and support the view of (1) a difference in receptors activated by DADLE in the guinea-pig ileum (mu) and mouse vas deferens (delta), as well as (2) possible differences in mu-receptors in these tissues. 相似文献
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The rapid movement of information technologies into health care organizations has raised managerial concern regarding the capability of today's institutions to satisfactorily manage their introduction. Indeed, several health care institutions have consumed huge amounts of money and frustrated countless people in wasted information systems implementation efforts. Unfortunately, there are no easy answers as to why so many health informatics projects are not more successful. In this light, the aim of this study is to provide a deeper understanding of how clinical information systems are being implemented by emphasizing research efforts on the dynamic nature of the process, that is, the “how” and “why” of what happened. Using a case study methodology, we examined the implementation of a patient charting system in the Burn Center of a large, not-for-profit, teaching hospital. Based on an in-depth examination of this implementation, several insights are offered to those who have responsibility for managing complex and risky clinical information system implementation projects. 相似文献