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11.
Summary To assess the benefit of further gold treatment of rheumatoid arthritis (RA) patients who had already received more than 6 g of this metal, 24 such patients were included in a double-blind trial. Besides this gold group comprising 11 patients who received gold (Auromyose®) in the same dosage schedule as before the study, the trial included a placebo group comprising 13 patients who received gold in a suspension diluted 1/100. In either group clinical, laboratory, and radiological data did not differ after 6 and 24 months in relation to the results at entry except for the serum gold concentrations, which were lower in the placebo group. We conclude that discontinuation of the treatment in RA patients who have received more than 6 g gold is not harmful to the patients for at least two years after withdrawal.  相似文献   
12.
Retrieval from long-term memory in patients with brain injuries was investigated with a memory scanning paradigm (Conway & Engle, 1994), that allows dissociation of scanning processes within short-term memory and memory retrieval processes from long-term memory. The study focused on the influence of brain injury on memory retrieval processes that are assumed to be automatic. Thirteen patients with memory impairment and 13 healthy matched control subjects were tested. In general, patients showed increased reaction times, but they showed set size independent retrieval from long-term memory indicating preserved automatic retrieval processes. In a subgroup of patients with more severe memory deficits, however, automatic retrieval processes appeared not to be intact. Learning profiles of the patients were characterized by smaller item chunks, indicating differences in the process of information acquisition.  相似文献   
13.
OBJECTIVES: To determine the reliability of reformatted 2D-CT for pre-operative planning of implant placement. METHODS: One hundred consecutive partially or fully edentate patients underwent 2-D reformatted CT pre-operative planning and subsequent implant placement. The number, site and size of the implants, the available bone height and anatomical complications were recorded. The pre-operative planning and the outcome at surgery were compared statistically using a percentage agreement and Kendall's correlation coefficient. RESULTS: Agreement between the pre- and intra-operative data was good for the number of implants (60%) and the selected sites (70%). From a total of 416 implants planned, 21 implants could not be placed because of intra-operative findings. Agreement was relatively poor for implant size (44%) and anatomical complications (46%). Kendall's correlation coefficient was highest for the number of implants (0.80) and implant sites (0.81). It was much lower for implant sizes (0.51) and did not reach significance for anatomical complications (0.09). CONCLUSIONS: Reformatted 2D-CT is reliable for the pre-operative assessment of the number and sites of implants in the jaws. It is less predictable for the implant size needed and poor for anatomical complications.  相似文献   
14.
BACKGROUND: The depletion of differential B cell and xenoreactive natural antibodies (XNA) by anti-delta and anti-mu injections was analyzed in adult mice. Sequential treatment with anti-delta and then anti-mu induces a complete depletion of B cells and XNA and represents a potential approach to induce xenograft tolerance. METHODS: Adult mice were injected with anti-mu, anti-delta, anti-delta then anti-mu, or control isotype monoclonal antibodies from day 0 to day 14. The different B-cell populations were analyzed by FACS and immunohistology. Ig production was tested by ELISA. XNA were analyzed by FACS. RESULTS: Anti-mu injections induced a depletion of IgMhigh, immature B cells, marginal zone B cells, and B1 cells and an increase of IgG-XNA production. Anti-delta injections induced mature conventional IgDhigh B-cell depletion and increased IgM-XNA production. Interestingly, sequential injections of anti-delta then anti-mu induced a depletion of immature B cells, mature B cells (MZ, B2, and B1), and XNA. CONCLUSIONS: These results demonstrate that mature B-cell depletion in adult mice can be obtained by mAb injections and depends on the surface immunoglobulin cross-linking threshold. Indeed, anti-mu mAb depleted IgMhigh B cells (MZ and B1) and anti-delta, IgDhigh B cells (B2). The differential B-cell suppression shows that conventional B cells are responsible in the IgG-XNA production and MZ and B1 cells in the IgM-XNA production. Sequential repeated injections of anti-delta then anti-mu mAb depleted all B-cell populations and suppressed the whole XNA production.  相似文献   
15.
There is a high prevalence of Ebola antibodies found in the Kenya population, related to geographical area and season, although the clinical disease was never found and the virus was not isolated. A field study was carried out in 7 hospitals in western Kenya, 1986 -1987 (including surveillance studies in suspect areas), to intensify collection and transport of samples, testing facilities, patient observation with record keeping and follow-up. This study involved 1109 admitted patients with fever and/or bleeding, 155 contacts of haemorrahagic fever antibody (Hfab) patients, and 916 people in suspect areas. Respectively 160,44 and 80 persons were found Hfab positive mainly to Ebola, using an indirect immunofluorescent assay. From 676 viral cultures no virus was isolated. A relationship between antibody titres and ecological factors, social habitat, age, sex or season was not found. The non-specificity of IF testing was demonstrated by: 1) the disagreement between the results of two reference laboratories; 2) the unpredictability of the titre conversation course; and 3) by proving a significant cross-reactivity with Borrelia burgdorferii antibodies, Plasmodium falcparum antibodies and Salmonella typhi antibodies. Renewed testing in 1995 of 90 positive sera (with low titres) showed 19 sera to be positive by Elisa (2 in Zaire, 1 in Sudan, 9 in Reston and 7 in Cote d'Ivoire) from which 4 were confirmed by IFI 2 in Reston and 2 in Cote d'Ivoire. These findings are more proof that non-human virulent strains of Filoviridae, especially Ebola virus, are around in Kenya.  相似文献   
16.
BACKGROUND: Comparison of the predictive value of four "diagnostic tests" for the outcome of shunting in patients with normal-pressure hydrocephalus (NPH). METHODS: Ninety-five NPH patients who received shunts were followed for 1 year. Gait disturbance and dementia were quantified by an NPH scale and handicap by a modified Rankin scale. Primary outcome measures were differences between the preoperative and last scores on both the NPH scale and the modified Rankin scale. Clinical and computed tomographic (CT) findings typical of NPH, absence of cerebrovascular disease, and a resistance to outflow of cerebrospinal fluid (CSF) >/= 18 mmHg/ml/minute were designated as a positive test outcome; clinical and CT findings compatible with NPH, presence of cerebrovascular disease, and an outflow resistance < 18 mmHg/ml/minute as a negative test outcome. RESULTS: For each of the four tests the percentage of patients classified as improved was significantly greater for those with positive than with negative test results. Measurement of CSF outflow resistance was the only significant prognostic factor for the improvement ratio in NPH scale and CT in the modified Rankin scale according to multivariate logistic regression analysis. The accurate predictive value of the combination of typical clinical and CT findings was 0.65, that of the positive test results of outflow resistance, clinical and CT findings was 0.74. CONCLUSION: The best strategy is to shunt NPH patients if their outflow resistance is >/= 18 mmHg/ml/minute or, when the outflow resistance is lower, if their clinical as well as their CT findings are typical of NPH.  相似文献   
17.
OBJECTIVE: To analyse the prevalence of neural tube defects in small geographical areas and seek to explain any spatial variations with reference to environmental lead and deprivation. SETTING: The Fylde of Lancashire in the north west of England. DESIGN: Cases were ascertained as part of a prospective survey of major congenital malformations in babies born in the Fylde to residents there between 1957 and 1981. A matched case-control analysis used infants with cardiovascular system, alimentary tract, and urinary system malformations as controls. Conditional logistic regression was used to assess the effects of more than 10 micrograms/l lead in drinking water and the Townsend deprivation score. RESULTS: The prevalence of neural tube defects in 1957-73 was higher in Blackpool, Fleetwood, and North Fylde, whereas the three control groups showed no significant spatial variation. In 1957-81 mothers living in electoral wards with either a higher proportion of houses with more than 10 micrograms/l lead in the water or a higher deprivation score had a greater risk of having a baby with a neural tube defect. For spina bifida and cranium bifidum alone, this was also true. For anencephaly, deprivation was less important although the effect of lead was still seen. In some neural tube defects, lead may act independently of other possible factors associated with deprivation. It seemed unlikely that lead levels changed significantly during the survey. The percentage of houses with 10 micrograms/l or more of lead in the water in 1984-5 was similar to that found in Great Britain 10 years previously. CONCLUSION: There is evidence to suggest that lead is one cause of neural tube defects, especially anencephaly. This could link the known preventive actions of hard water and folic acid. Calcium is a toxicological antagonist of lead. One cause of a deficiency of folic acid is impaired absorption secondary to zinc deficiency, which may be produced or exacerbated by lead.  相似文献   
18.
19.
In a prospective two-centre study targeted US was performed as an adjunct to mammography in a population of 1103 patients with 272 breast cancers, 517 benign lesions and no abnormalities in 314 patients. The purpose of the study was to analyse the distribution of the different US variables among the breast lesions and to determine the prognostic value of these variables with respect to the diagnosis of malignancy. The following variables were analysed: border; contour; orientation; structure; echogenicity; sound transmission; and size. These variables were correlated with the definitive diagnosis and univariate analysis was performed. A statistically significant association with breast cancer (p < 0.001) was present for irregular border; ill-defined contour; indeterminate or vertical orientation; homogeneous, complex or heterogeneous structure; hypoechogenicity; and unchanged or decreased sound transmission. Multivariate analysis showed a high independent prognostic value for malignancy for irregular border, followed by ill-defined contour and unchanged or decreased sound transmission. However, their discriminative power was not absolute: in 38 cancers none of the malignant US variables were present, and in 11 benign lesions all variables were present. There were hardly any benign-looking lesions that proved to be malignant. Received: 6 October 1999; Revised: 3 March 2000; Accepted: 26 June 2000  相似文献   
20.
Change in the accommodative force on the lens of the human eye with age   总被引:1,自引:0,他引:1  
The aim of the study was to determine the age-dependence of the accommodative force on the lens in order to make it clear whether the causes of presbyopia are due to lenticular or extralenticular changes. A finite element model of the lens of an 11-, 29- and 45-year-old human eye was constructed to represent the fully accommodated state. Subsequently, the force that was needed to mould the lens into its unaccommodated state was calculated. The force on the lens appeared to be preserved with age, with only a slight increase to a value of approximately 0.06N. In conclusion, the preservation of the net force delivered by the extralenticular ciliary body indicates that the causes of presbyopia must be ascribed to lenticular changes.  相似文献   
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