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Delayed graft function (DGF) in cadaver kidney transplants is a common problem and is often due to acute tubular necrosis (ATN). DGF in transplants may have a deleterious effect on long-term graft survival. Since thyroid hormone has been shown to hasten recovery from ATN in experimental models, we designed a trial to determine if a defined course of triiodothyronine (T3) would improve the short- or long-term outcome of patients with DGF in cadaveric transplants. A prospective, randomized, placebo controlled, double blind trial of T3 was carried out in patients with DGF in cadaveric renal transplants. End-points were percentage requiring dialysis, percentage recovering function, time to recovery and length of hospital stay. Long-term outcomes were percentage grafts functioning at 1 year and mean serum creatinine at 1 year. Forty-four patients were randomized to receive either T3 or placebo. Three patients were dropped from each group when early biopsies disclosed that DGF was due to rejection. The groups were well matched by age, cold ischemia time of the graft, and percentage reactivity to a random panel of antigens. Baseline thyroid function studies, including T3, reverse T3 (rT3), and thyroid stimulating hormone (TSH) levels, were similar between the two groups and typical of 'euthyroid-sick syndrome'. T3 had no effect on percentage requiring dialysis, time to recovery, percentage recovering function, or length of stay. At 1 year follow-up, graft function was similar in both groups and significantly lower than that seen in patients with good initial function. Thyroid hormone, given early in the course of DGF in cadaver kidney recipients, had no effect on the course of DGF. Long-term graft function is impaired in patients who experience post-transplant DGF compared to those who have good initial function.  相似文献   
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It is known that two gluconokinases are inducibly expressed during the utilization of gluconate by E. coli. One is thermoresistant (activity stable for 3 h at 30 °C) and the other thermosensitive (losses 75% or more of its activity under the above conditions). The thermoresistant gluconokinase (EC 2.7.1.12) was isolated, purified and characterized for the first time from the E. coli mutant Ca26, a K12 derivative which lacks the thermosensitive activity. The enzyme was purified 43 fold with a recovery of 11%. The Mr of the enzyme was 100 kDa with three equal subunits of approximately 29.5 kDa. The enzyme exhibited Michaelis-Menten kinetics and the Km values for gluconate and ATP were 0.02 mM and 0.045 mM respectively.  相似文献   
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PURPOSE: The aim of the present investigation was to develop a new ocular inflammation model in the rabbit by comparison of the inflammation response induced by the topical application of several irritating agents (carrageenan, Freund's adjuvant, alkali and croton oil). METHODS: The following parameters were determined after the application of each irritant to the eyes of female, white, New Zealand rabbits: Corneal edema and the Tyndall effect (slit-lamp biomicroscopy), corneal thickness (biometer-pachometer) and aqueous humor levels of the prostaglandin E2 (R.I.A), total protein (Weichselbaum technique), albumin, albumin/globulin (Doumas technique) and leukocytes (coulter counter). RESULTS: Croton oil 1-4% (40 microl) produced edema and a Tyndall which showed a proportional increase with croton oil concentration. Ultrasonic pachometer measurement of the variation in corneal thickness (3-168 h) showed a dose-dependent response (p<0.01) from the 8th to the 168th hour. Uveitis and considerable increases in the levels of the prostaglandin E2 (4.50+/-0.40 pg/0.1 ml vs. 260.03+/-2.03 pg/0.1 ml), total protein (0.25+/-0.05 g/l vs. 2.10+/-0.08 g/l), albumin, albumin/globulin and leukocytes were observed in the aqueous humor 24 h after topical application of croton oil 3% (40 microl). All the values obtained were statistically significant (p<0.01). CONCLUSIONS: The topical application of 3% croton oil (40 microl) was most appropriate for the evaluation of the inflammatory process in the anterior chamber and for the determination of the effects of intraocular penetration. The inflammatory mechanism in this model is thought to involve the activation of the arachidonic acid pathway accompanied by the breakdown of the blood-aqueous barrier permitting high molecular weight proteins to enter the aqueous humor. Typology: anterior uveitis with corneal edema.  相似文献   
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BackgroundMembers of the public are increasingly engaged in health‐service and biomedical research and provide input into the content of research, design and data sharing. As there is variation among different communities on how research is perceived, to engage all sectors of the general public research institutions need to customize their approach.ObjectiveThis paper explores how research institutions and community leaders can partner to determine the best ways to engage different sectors of the public in research.DesignFollowing a literature review, a research institution engaged with four different sectors of the public through their respective representative community‐based organizations (CBOs) by interviews with leaders, community member focus groups and a joint project.SettingSan Diego and Imperial Counties, California, United States of America (USA).ConclusionBefore embarking on more specific research projects, investigators can gain valuable insights about different communities'' attitudes to, and understanding of, health services and biomedical research by interacting directly with members of the community, collaborating with community leaders, and jointly identifying steps of engagement tailored to the community.  相似文献   
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