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61.
The authors investigated the ability of recombinant human gamma-interferon (rhIFN-gamma) to influence production of complement and expression of human leukocyte antigens (HLA) by human scleral fibroblasts in culture. Cell cultures were established by explanting sclera from normal human donor eyes. To study complement production, fibroblasts were treated with 500 units/ml rhIFN-gamma in cell culture, and media were tested for complement components by hemolytic assay after 0, 1, 3, 6, 9, and 11 days. To induce Class II HLAs, fibroblasts were exposed to rhIFN-gamma at concentrations ranging from 10-500 units/ml and incubated for 1, 3, and 6 days. The HLAs were detected by immunofluorescence in conjunction with flow cytometry. Class I antigen was detected using a monoclonal antibody directed against beta 2-microglobulin. Class II histocompatibility antigens were identified using monoclonal antibodies specific for HLA-DR, -DP, and -DQ. Although complement component C1 was produced constitutively in cell culture, the addition of rhIFN-gamma resulted in an increase in production. Complement components C2 and C4 were detected only after treatment with rhIFN-gamma. Complement production was completely inhibited by cycloheximide, and C3, C5, C6, and C7 were not present in cell culture media with or without rhIFN-gamma. Class I antigen was present on all cells before induction, and an increase in expression was noted after exposure to rhIFN-gamma. Class II antigens were absent before induction with rhIFN-gamma. After treatment with rhIFN-gamma, scleral fibroblasts expressed HLA-DR, -DP, and -DQ in a dose-dependent, time-related fashion. These findings suggest that rhIFN-gamma has multiple effects on scleral fibroblasts: (1) increased production of C1, (2) production of C2 and C4, (3) up-regulation of Class I antigen expression, and (4) expression of Class II antigens. They also suggest that scleral fibroblasts have the potential to participate in immunologic diseases of the eye.  相似文献   
62.
The changes of intestinal permeability before and after a gluten load were studied. The study group comprised 27 patients with coeliac disease (mean age 12.3 years) and 19 healthy controls matched by sex and age. Intestinal permeability was studied by measuring the urinary excretion of two sugars, lactulose and L-rhamnose, before and six hours after the ingestion of five palatable biscuits made with 50 g of gluten powder. The patients with coeliac disease had been on a gluten free diet during the previous two years. After the gluten load lactulose and L-rhamnose urinary excretion changed significantly in patients, and a significant increase in the lactulose: L-rhamnose ratio was also observed. No significant changes were observed in the controls. In view of the modification of the three biopsies diagnostic protocol made by the European Society for Paediatric Gastroenterology and Nutrition, permeability tests associated with single gluten challenges may be an added contribution to the accuracy of the diagnosis in childhood.  相似文献   
63.
OBJECTIVE: To compare effectiveness of two techniques for removing football face masks: cutting loop straps [cutting tool: FMXtractor (FMX)] or removing screws with a cordless screwdriver and using the FMXtractor as needed for failed removals [combined tool (CT)]. Null hypotheses: no differences in face mask removal success, removal time or difficulty between techniques or helmet characteristics. DESIGN: Retrospective, cross-sectional. SETTING: NOCSAE-certified helmet reconditioning plants. PARTICIPANTS: 600 used high school helmets. INTERVENTIONS: Face mask removal attempted with two techniques. MAIN OUTCOME MEASUREMENTS: Success, removal time, rating of perceived exertion (RPE). RESULTS: Both techniques were effective [CT 100% (300/300); FMX 99.4% (298/300)]. Use of the backup FMXtractor in CT trials was required in 19% of trials. There was significantly (P<0.001) less call for the backup tool in helmets with silver screws (6%) than in helmets with other screws (31%). Mean removal time was 44.51+/-18.79s (CT: 37.84+/-15.37s, FMX: 51.21+/-19.54s; P<0.001). RPE was different between techniques (CT: 1.83+/-1.20, FMX: 3.11+/-1.27; P<0.001). Removal from helmets with silver screws was faster (Silver=33.38+/-11.03, Others=42.18+/-17.64; P<0.001) and easier (Silver=1.42+/-0.89, Other=2.23+/-1.33; P<0.001). CONCLUSIONS: CT was faster and easier than FMX. Most CT trials were completed with the screwdriver alone; helmets with silver screws had 94% screwdriver success. Clinically, these findings are important because this and other research shows that compared to removal with cutting tools, screwdriver removal decreases time, difficulty and helmet movement (reducing potential for iatrogenic injury). The combined-tool approach captures benefits of the screwdriver while offering a contingency for screw removal failure. Teams should use degradation-resistant screws. CLINICAL RELEVANCE: Sports medicine professionals must be prepared with appropriate tools and techniques to efficiently remove the face mask from an injured football player's helmet.  相似文献   
64.
An excellent physician must be aware of the countless issues that affect each patient's health. Many medical education programs expose students to a broad spectrum of disparate knowledge and hope they will integrate all the pieces into a coherent whole. The authors describe an explicit approach to integration used at Harvard Medical School since 2003 that aims to enhance students' learning in medical school and throughout their medical careers: the Mentored Clinical Casebook Project (MCCP). The MCCP is constructed on the premise that such integration does not occur suddenly but, rather, is an unending process. A first-year student is assigned to one clinician and follows one patient for one year. The student is expected to spend as much time with the patient as possible, in both clinical and nonclinical settings, seek help from the clinician, and consult other experts and sources to develop a complete picture of the patient's life. The student must produce a casebook that includes, but is not limited to, the patient's history; basic science, clinical, socioeconomic, and cultural issues; and self-reflection. The MCCP is intended to allow students to develop a deeper and more diverse understanding of what comprises a patient's health care life, to discern the patient as a person and the person as a patient. This educational project has been popular with students since its inception, providing them with a personal framework from which to address the needs of future patients and introducing them to how much they will continue to learn from their patients.  相似文献   
65.
Numbers of interleukin-12 (IL-12) producing cells were quantitated in the peripheral blood of healthy donors and tuberculosis patients by the ELISPOT assay. We observed that (i) stimulation with mycobacteria increases numbers of IL-12 producers from healthy donors and (ii) tuberculosis patients have larger numbers of IL-12 producers than healthy donors. Our data emphasize the importance of Il-12 in immunity to tuberculosis.  相似文献   
66.
67.
Ankle fusion: a retrospective review   总被引:1,自引:0,他引:1  
A D Aaron 《Orthopedics》1990,13(11):1249-1254
The results of ankle fusion were reviewed in 26 patients who underwent 32 arthrodesis procedures. Posttraumatic degenerative arthritis was the most common indication for fusion (54%). Crossed cancellous screws were the primary method employed (43%), with an external fixator being used in 22% of cases. The overall union rate was 81%, with both crossed cancellous screws and external fixation attaining the best results (86%). Nonunion and infection were the most frequent complications. Progression of subtalar arthritis was demonstrated in 29% of patients postoperatively. Seventy-eight percent of patients graded extremity appearance as excellent or good, with the majority being able to return to work.  相似文献   
68.
OBJECTIVE: To determine clinical utility of fine needle aspiration (FNA) in parotid neoplasia. STUDY DESIGN AND SETTING: Retrospective cohort study. METHODS: FNA and final pathology data were reviewed for patients who underwent parotidectomy for malignancy. Surgical outcomes were compared between patients with malignant cytology versus nonmalignant/nondiagnostic cytology. RESULTS: Twenty-seven of 33 primary malignant parotid lesions underwent FNA. Seventeen (63.0%) patients were diagnosed with cancer on FNA. The remaining 16 patients did not undergo FNA (n = 6), had a nondiagnostic FNA specimen (n = 5), or were incorrectly diagnosed with a benign lesion (n = 5). Patients who went on to parotidectomy with intent to treat malignancy based on FNA had significantly higher rates of upfront neck dissections (47.1% vs 12.5%, P = 0.036) as well as clear pathological margins (70.6% vs 31.3%, P = 0.027) vs those with nonmalignant FNA diagnoses. CONCLUSIONS: Preoperative FNA diagnosis of malignancy improves surgical treatment of parotid cancer. SIGNIFICANCE: FNA in the evaluation of parotid masses should strongly be considered.  相似文献   
69.
The impetus for the devolopment of living related liver programmes lies with donor shortage, which relates inversely to the success of generating cadaveric donors. A shrinking or non-existent cadaveric donor pool leads to an increased death rate among potential recipients awaiting transplantation. The living related liver programmes have by and large been successful, though it is accepted that there is potentially a significant risk to the donors. The technique of live donor liver transplantation is clearly here to stay, but the selection of suitable donors is between the family and the unit. Consequently, because of the lack of international guidelines, the programmes are open to abuse. Steps should be taken to establish either mechanisms of control or a worldwide register to combat this potential.  相似文献   
70.
Zusammenfassung Operationsziel überdachung des Femurkopfes bei Hüftgelenkdysplasie. Indikationen Dysplastisches Acetabulum bei Patienten mit neuromuskul?ren und nichtneuromuskul?ren Erkrankungen. übergro?es, flaches Acetabulum. Fehlen einer lateralen und kranialen überdachung. Kontraindikationen Y-Fuge geschlossen, Wachstum abgeschlossen. Stark verformter Femurkopf. Operationstechnik Modifizierter Zugang nach Salter/Smith-Petersen. Freilegung und Teilung der Apophyse des Beckenkammes mit einem Messer. Freilegung der Darmbeinschaufel. Osteotomie der ?u?eren Wand des Iliums; sie wird vorsichtig mit Hilfe eines gebogenen mei?els nach unten gebogen und in dieser Stellung durch Einsetzen von trikortikalen Beckenkammsp?nen gehalten. Eine Osteosynthese ist nicht notwendig. Becken-Bein-Gipsverband mit Einschlu? des gegenseitigen Oberschenkels für sechs Wochen. Ergebnisse Zwischen 1987 und 1997 wurden 26 Hüften von 23 Patienten operiert. überwiegend handelte es sich um Kinder mit spastischen Paresen. Folgende zus?tzliche Eingriffe wurden vorgenommen: Offene Reposition zehnmal, Femurosteotomie 18mal und Tenotomien sowie Muskelabl?sungen 15mal. Der Durchschnittswert des azetabul?ren Index verbesserte sich von 32° auf 22°, der durchschnittliche Wert des Kopfzentrum-Pfannenrand-Winkels von −25° auf 22° und der durchschnittliche Migrationsindex von 62% auf 69%. Als Komplikationen wurden beobachtet: eine erneute Subluxation, ein frühzeitiger Verschlu? des Y-Knorpels, eine Fraktur des anderen Femur, einmal heterotope Ossifikationen und einmal eine Infektion der Harnwege.  相似文献   
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