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81.
E L Bove C Bull J Stark M de Leval F J Macartney J F Taylor 《Archives of disease in childhood》1983,58(2):137-141
All 212 neonates undergoing cardiac surgery at this hospital during the 5-year period from 1976 to 1980 inclusive were reviewed. Forty required open heart surgery with 23 (57%) deaths. One hundred and seventy-four neonates underwent non-bypass procedures and could be divided into three groups: group 1 (82 patients) had inadequate pulmonary blood flow, group 2 (33 patients) had increased pulmonary blood flow or inadequate mixing, and group 3 (59 patients) had coarctation of the aorta, alone or with associated lesions. Forty-four (25%) of the neonates undergoing non-bypass procedures died. Two required bypass surgery later in the first month of life. Metabolic acidosis and the need for preoperative respiratory support were appreciably greater in non-surviving patients. The spectrum of diagnoses encountered and types of operative procedures performed are analysed. 相似文献
82.
Kaestel CG Jørgensen A Nielsen M Eriksen KW Ødum N Holst Nissen M Röpke C 《Experimental eye research》2002,74(5):627-637
The purpose of this study was to characterize the effects of human retinal pigment epithelial (RPE) cells on activated T cells. Activated T cells were cocultured with adult and foetal human RPE cells whereafter apoptosis and proliferation were determined by flow cytometry and (3)H-Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact-dependent mechanism. The RPE cells inhibitory abilities were not affected by blocking of any of the tested surface molecules. The inhibition of the T cells' proliferation correlates with a decreased expression of IL2R-beta and -gamma chains. The T cells regain their ability to proliferate and increase their IL2R-beta and -gamma chain expression within 24 hr after removal from the coculture. It is concluded that the cultured human adult and foetal RPE cells inhibit the proliferation of activated T cells by a process that does not involve apoptosis. It depends on cell contact but the involved surface molecules were not revealed. The proliferation inhibition correlates with a modulation of the T cells' expression of IL2R, and is reversible. 相似文献
83.
Steen Mogens Lauge Lasson 《Child & youth care forum》2002,31(3):163-176
This article emphasizes the fact that culture surrounds and influences the young people in child and youth care programs all the time, and that child and youth care workers must become cultural mediators for the culturally undernourished when assisting youth in care. This work must add to psychological pedagogics and social pedagogics a third new dimension, cultural pedagogics. Through raising and answering a series of six questions concerning culture, the author hopes to stimulate better practice and educational training in the cultural preparation of young people receiving child care services. 相似文献
84.
Age-related macular degeneration (AMD) is a common macular disease affecting elderly people in the Western world. It is characterised by the appearance of drusen in the macula, accompanied by choroidal neovascularisation (CNV) or geographic atrophy. The disease is more common in Caucasian individuals than in pigmented races. In predominantly Caucasian populations, the age-standardised prevalence of AMD in at least one eye is 7760 cases per million. The age-standardised cumulated 1-year incidence of AMD in at least one eye is 1051 cases per million individuals. AMD is the most important single cause of blindness among Caucasian individuals in developed countries. Blindness resulting from AMD rarely occurs before age 70, and most cases occur after age 80. The age-standardised 1-year incidence of legal blindness resulting from AMD is 212 cases per million. Two-thirds of AMD cases have CNV (exudative cases); the remainder has only geographic atrophy. In cross-sectional population-based studies about 45% of eyes with AMD have visual acuity reduced to 20/200 or worse. This is true both for exudative AMD and pure geographic atrophy. Age and genetic predisposition are known risk factors for AMD. Smoking is probably also a risk factor. Preventive strategies using macular laser photocoagulation are under investigation, but their efficacy in preventing visual loss is as yet unproven. There is no treatment with proven efficacy for geographic atrophy. Optimal treatment for exudative AMD requires a fluorescein angiographic study and a physician capable of interpreting it. For CNV not involving the foveal centre, the only evidence-based treatment is laser photocoagulation. For AMD cases with subfoveal CNV, good visual acuity, and predominantly classic fluorescence pattern on fluorescein angiography, photodynamic therapy with verteporfin is the treatment of choice. Photodynamic therapy is also effective in eyes with pure occult CNV and evidence of recent disease progression. For new subfoveal CNV with poor vision and recurrent CNV, laser photocoagulation can be considered. 相似文献
85.
86.
OBJECTIVES: The objectives of this study were to investigate the prevalence of posttraumatic stress disorder in patients with a first myocardial infarction compared with a random sample of healthy controls and to determine variables associated with the disorder. DESIGN: A questionnaire was distributed to 112 consecutive patients 4 to 6 weeks after infarction and to 115 healthy controls selected randomly from the general population. Objective clinical measures were obtained from the patients' medical records. RESULTS: Twenty-five (22%) patients qualified for a diagnosis of posttraumatic stress disorder (PTSD) compared with 8 (7%) controls with patients being more than a three-fold (OR: 3.84; 95% CI: 1.65 to 8.94) risk of having the disorder. When adjusting for other variables, the risk was reduced to above a two-fold risk (OR: 2.71; 95% CI: 0.99-7.41). In patients and controls, depression and neuroticism were associated with a diagnosis of PTSD adjusting for other variables. In patients, anxiety was associated with a diagnosis of PTSD adjusting for other variables. Left ventricular ejection fraction and symptoms of angina pectoris were not related to a diagnosis of PTSD in the patient group. CONCLUSIONS: Given that previous research has shown that persons with PTSD are at increased risk of cardiovascular diseases, cardiac patients with the disorder may be at a higher risk of recurrent cardiac events. Although longitudinal studies are needed to confirm such a relationship, this disorder should not be overlooked because of its potential role in reinfarctions and mortality. 相似文献
87.
The properties of three types of indentation stimulators: filament indenters, a spring gauge indenter, and an electromechanical stimulator, were evaluated by actuating each device against a 3-direction load cell. The on-axis loads produced by filament indenters were independent of the degree of buckling. The off-axis loads produced by a filament increased with the degree of buckling of the filament, and had magnitudes that were up to 25% of the on-axis load. Repeated applications of a filament produced loads whose magnitudes were very consistent. Offsetting the handle of a filament indenter altered the magnitude and the direction of the off-axis load. Because these factors were poorly controlled in hand held trials, off-axis loads were more variable in hand held trials. The spring gauge stimulator was, when hand held, very susceptible to creating large off-axis loads. When the off-axis loads were large, the spring gauge indicator underestimated the true on-axis loads. The electromechanical stimulator produced loads with a very high degree of consistency and could be arranged so that it produced very small off-axis loads. 相似文献
88.
Johansen C Feychting M Møller M Arnsbo P Ahlbom A Olsen JH 《American journal of epidemiology》2002,156(9):857-861
To address concern about the potential cardiovascular effects of occupational exposure to electromagnetic fields in the 50- to 60-Hz frequency band, the authors launched an epidemiologic study of the incidence of severe cardiac arrhythmia, as indicated by the need for a pacemaker, in a nationwide cohort of Danish utility workers. The cohort of 24,056 men employed at utility companies between 1900 and 1993 was linked to the nationwide, population-based Danish Pacemaker Register, and the numbers of persons who had undergone pacemaker implantation between 1982 and 2000 were compared with corresponding numbers in the general population. In addition, the data on the utility workers were fitted to a multiplicative Poisson regression model in relation to estimated levels of exposure to 50-Hz electromagnetic fields. Overall, based on 135 men with pacemakers (140 expected), there was no increased risk of severe cardiac arrhythmia among the utility employees; the risk estimate was 0.96 (95% confidence interval: 0.81, 1.14). No clear dose-response pattern emerged with increasing levels of exposure to electromagnetic fields or with duration of employment. These results are largely reassuring, since they do not support the hypothesis of a link between occupational exposure to electromagnetic fields and an excess risk of severe cardiovascular arrhythmia leading to permanent implantation of a pacemaker. 相似文献
89.
A HLA-A2 restricted human CTL line recognizes a novel tumor cell expressed p53 epitope 总被引:2,自引:0,他引:2
Würtzen PA Claesson MH 《International journal of cancer. Journal international du cancer》2002,99(4):568-572
A p53 peptide-specific CTL line was generated through stimulation with autologous monocyte-derived dendritic cells (DC) pulsed with wild-type HLA-A2 binding p53 derived peptides. A p53 peptide-specific CD8(+) CTL line was established from a healthy HLA-A2 positive donor. The CTL line was characterized with respect to specificity, affinity and killing of cell lines derived from p53 mutated spontaneous tumors. The CTL line demonstrated lysis of p53(139-147) pulsed target cells and cold target inhibition experiments as well as antibody blocking confirmed that the killing was epitope-specific, HLA-A2 restricted and dependent on CD8-binding. Interestingly, the affinity of the CTL line was only in the micromole per liter range and target cells pulsed with less than 0.01 microM peptide were not recognized. Furthermore, 3 HLA-A2(+) p53 mutated tumor cell lines were efficiently lysed by the CTL line, indicating that this novel p53 peptide epitope is endogenously processed and presented by the HLA-A2 molecules of the tumor cells. In conclusion, CTL reactivity towards a wild-type p53 peptide was revealed through induction with DC pulsed with a pool of HLA-A2 binding p53 peptides. In addition, the CTL line, which expressed relatively low affinity for the HLA-A2/peptide complex, was able to kill 3 different HLA-A2(+) p53 mutated tumor cell lines. The present and our previous observations expand the number of p53-derived peptides suitable for vaccination protocols for cancer patients with p53 positive tumors. 相似文献
90.