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21.
Geoffrey Thiele Molly Bicak Helen Grierson Patrick Lai David Purtilo 《Journal of immunological methods》1987,100(1-2):249-259
An enzyme-linked immunosorbent assay (ELISA) was used to measured IgG antiboody titers againt a synthetic peptide whose sequence was derived from the glycine-alanine repeating region of Epstein-Barr virus nuclear associated antigen 1 (EBNA-1). Antibody titers were determined in sera from 15 normal subjects, sera from 21 normal male siblings of X-linked lymphoproliferative syndrome (XLP) patients, from 20 XLP patients comprising a total of 42 samples, and ten samples before and ten samples after gamma-globulin therapy in ten patients with XLP. Data analysis demonstrated that while there are differences between the ELISA and ACIF, they appear to measure a similar response as demonstrated by their correlation coefficient (0.77) and the GMT to EBNA observed by both methods. No cross-reactivity of cytomegalovirus antibodies to the EBNA-1 peptide was observed by immunobv using adsorption against AD-169 infected MRC-5 cells.. However, non-specific binding was observed if samples were not pre-incubated in a 10% goat serum PBS-Tween 20 solution. This pre-treatment removed the non-specific binding that falsely elevated GMT in approximately 15% of both normal and XLP samples in ELISA. The ELISA system appears to be a sensitive, reproducible and objective test that may be useful for assessing the antibody responses of patients to the EBNA-1 protein. 相似文献
22.
Pediatric orbital pseudotumor may be associated with iritis, unlike the adult form of this disorder. However, orbital pseudotumor is seldom considered in the differential diagnosis of childhood uveitis. We report two cases of children with uveitis who were ultimately diagnosed as having orbital pseudotumor. No proptosis was noted in either child. For those pediatric patients with a persistent or recurrent uveitis and a previous negative diagnostic workup, the possibility of an orbital pseudotumor should be considered and ultrasonography, magnetic resonance imaging, and/or computed tomography performed. 相似文献
23.
We have previously described the development of new hepatic surgical techniques using the ultrasonic surgical dissector. With 10 years' experience, we have found that major liver resections have been simplified and that the technique is repeatable in hands other than our own. Thirty-three patients had 37 tumors, averaging 5.65 cm in size, resected with an average blood loss of only 1,020 mL per case, which included 5 right trisegmentectomies, 12 lobectomies, 15 segmental resections, and 4 subsegmental resections. Twenty-two patients had metastatic colorectal cancer. Blood transfusion requirements averaged only 2.24 units in long-term survivors, which was significantly less than the 3.5 units received by patients who have since died (p = 0.092). There were no operative deaths. The median survival of these 22 patients was 56 months, and the 5-year actuarial survival rate was 35%. All of the early deaths occurred in patients with more than four tumors, and no patient with less than four tumors died before 42 months with recurrent disease. Six patients had bilateral tumors, and the fact that patients survived into the fourth and fifth post-resectional year indicates that resection was worthwhile. All these patients had Dukes' C primary tumors, but we found no statistical difference in survival between patients with Dukes' B and Dukes' C lesions. The results indicate that hepatic resection with the ultrasonic surgical dissector decreases blood loss, requires few transfusions, is safe to perform, and is associated with excellent long-term survival. 相似文献
24.
Dr Robert M. Lynd-Stevenson Stuart Byrne Sue Dolman Michael Harrison Brian Williams 《Clinical Psychologist》2007,11(2):45-49
The present paper outlines the development and evaluation of an allocation committee to distribute community placements on an equitable basis between universities. Although based on our experience in South Australia with the University Placement Allocation Committee (UPAC), the primary goal is to outline the steps that would be useful if placement coordinators at other universities in Australia decided to establish and maintain an allocation committee. A survey of field supervisors was also conducted and field supervisors endorsed UPAC as a constructive mechanism for allocating community placements. 相似文献
25.
26.
Transfer of the HIV-1 cyclophilin-binding site to simian immunodeficiency virus from Macaca mulatta can confer both cyclosporin sensitivity and cyclosporin dependence 总被引:5,自引:0,他引:5
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Anatoly A. Bukovsky Andreas Weimann Molly A. Accola Heinrich G. Gttlinger 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(20):10943-10948
HIV-1 specifically incorporates the peptidyl prolyl isomerase cyclophilin A (CyPA), the cytosolic receptor for the immunosuppressant cyclosporin A (CsA). HIV-1 replication is inhibited by CsA as well as by nonimmunosuppressive CsA analogues that bind to CyPA and interfere with its virion association. In contrast, the related simian immunodeficiency virus SIVmac, which does not interact with CyPA, is resistant to these compounds. The incorporation of CyPA into HIV-1 virions is mediated by a specific interaction between the active site of the enzyme and the capsid (CA) domain of the HIV-1 Gag polyprotein. We report here that the transfer of HIV-1 CA residues 86–93, which form part of an exposed loop, to the corresponding position in SIVmac resulted in the efficient incorporation of CyPA and conferred an HIV-1-like sensitivity to a nonimmunosuppressive cyclosporin. HIV-1 CA residues 86–90 were also sufficient to transfer the ability to efficiently incorporate CyPA, provided that the length of the CyPA-binding loop was preserved. However, the resulting SIVmac mutant required the presence of cyclosporin for efficient virus replication. The results indicate that the presence or absence of a type II tight turn adjacent to the primary CyPA-binding site determines whether CyPA incorporation enhances or inhibits viral replication. By demonstrating that CyPA-binding-site residues can induce cyclosporin sensitivity in a heterologous context, this study provides direct in vivo evidence that the exposed loop between helices IV and V of HIV-1 CA not merely constitutes a docking site for CyPA but is a functional target of this cellular protein. 相似文献
27.
Factors predicting a successful outcome after pharmacologic bowel compensation. 总被引:3,自引:0,他引:3
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OBJECTIVES: The authors determined those factors that predict a successful outcome in patients who receive pharmacologic agents to promote bowel absorption after massive intestinal resection. SUMMARY BACKGROUND DATA: Patients with the short bowel syndrome are maintained on long-term total parenteral nutrition (TPN) or more frequently considered for intestinal transplantation as part of their treatment program. The authors have administered a combination of trophic agents and a specialized diet to further enhance intestinal compensation and optimize nutrient absorption in patients with intestinal failure. METHODS: Forty-five TPN-dependent adults with a jejunal-ileal remnant < or = 50 cm and a portion of colon in continuity were treated with growth hormone, glutamine, and a modified diet for 4 weeks and observed for an average of 1.8 years. RESULTS: The average age of the patients was 43 years, the average jejunal-ileal length was 23 cm, and the average length of time the patient received TPN was 4.3 years. After 4 weeks of therapy, 26 (58%) were free of TPN support. Predictors of a favorable response included greater bowel length, lower body weight, and greater bowel length-body weight ratio. At follow-up, the percentage of patients who were not receiving TPN had fallen to 40%. CONCLUSIONS: Approximately half of a group of patients, thought to have absorptive surface area inadequate to be independent of TPN support, can maintain themselves on enteral feedings after this intestinal rehabilitation program. Because of the risk, costs, and alterations in lifestyle associated with long-term TPN or intestinal transplantation or both, it seems prudent to consider a program of bowel rehabilitation with an individual patient before embarking on another therapeutic plan. 相似文献
28.
Experimental columnar metaplasia in the canine oesophagus 总被引:7,自引:0,他引:7
P Gillen P Keeling P J Byrne A B West T P Hennessy 《The British journal of surgery》1988,75(2):113-115
Regeneration of canine oesophageal mucosa was studied under basal conditions and in the presence of gastro-oesophageal reflux. In normal circumstances mucosal defects in the oesophagus regenerate by squamous epithelium. In the presence of gastro-oesophageal reflux of either acid or a combination of acid and bile, regeneration was frequently by columnar epithelium (Barrett's oesophagus). This columnar regeneration was not seen with bile reflux alone. By the use of squamous barriers to proximal migration of columnar epithelium in the stomach, it was demonstrated that columnar re-epithelialization may occur from cells intrinsic to the oesophagus and is not dependent on proximal migration of cardiac columnar epithelium. The cell of origin of this epithelium may be located in oesophageal gland ducts and is likely to be a multipotential stem cell since the regenerated columnar epithelium may contain goblet and parietal cells not normally found in the oesophagus. This epithelium is morphologically distinct on mucin histochemistry from cardiac columnar epithelium. These findings support the concept that Barrett's epithelium is metaplastic. 相似文献
29.
Restless legs syndrome (RLS) is one of the commonest movement disorders affecting sleep and also daytime functioning. The prevalence may be 8%–10% of the white Caucasian population. The diagnosis is simple and is based on a well-validated clinical questionnaire, yet misdiagnosis is common and the condition remains underdiagnosed and consequently inappropriately treated, often causing great distress to the sufferers. In spite of robust evidence for effective treatment of RLS, patients may often be told to “put up with the symptoms” and suffer the consequence of years of poor sleep which may lead to major lifestyle changes. This review addresses the diagnostic issues, the differential diagnosis, and the evidence base for treatment of the common condition. 相似文献
30.