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1.
OBJECTIVE: The purpose of this study was to examine the effect of optimal seated positioning in individually fitted furniture versus suboptimal seated positioning in standard classroom furniture on typical 6- and 7-year-old children's object manipulation skills as measured by the In-hand Manipulation Test (IMT). METHOD: An experimental research design was used to compare IMT performance of two groups of 20 children. One group was positioned in standard, too-large classroom furniture that did not support an optimal seated position, and one group was positioned optimally in furniture fitted to each child for tabletop activities, which allowed for hip flexion to 90 degrees, and foot placement on the floor, and the table to be at flexed elbow height. RESULTS: Independent groups' t tests indicated that children who were optimally positioned performed significantly better (t = -2.77, df = 38, p < .01) than children who were tested in the too-large standard classroom furniture. The difference between groups was greater on the more difficult object manipulation items (t = -3.29, df = 38, p = .001) than on the easier items (t = -1.38, df = 38, p = .08). Age and gender may have differentially affected the results. CONCLUSION: The study's results suggest that the fit of furniture relative to the child's size may have a significant impact on a young, typical child's object manipulation skills. Complex hand skills, such as those involving in-hand manipulation with stabilization, appear to be more affected by the quality of the child's seated position than are simpler, more well-established skills. Findings suggest that test administrators should strive to test young children in the most optimal seated position possible, particularly when the test involves complex hand skills. Further study is needed to assess the impact of the fit of furniture on hand skills in children with disabilities and on children's performance of other tasks.  相似文献   
2.
Metastatic bone disease from occult carcinoma: a profile   总被引:3,自引:0,他引:3  
Summary To assess the general profile of metastatic bone disease from occult primary carcinoma, the records of 172 patients with skeletal metastases seen between 1965 and 1985 were reviewed. In 51 patients (30%), the origin of the primary could not be identified when bone metastases were first diagnosed. This group were predominantly male with a high incidence of spinal metastases, cord compression and pathological fractures, and a significantly shorter (P<0.1) survival compared with bony metastases when the primary was known. The site of the primary was established in 33 patients (65%), mostly at autopsy. Lung carcinoma was by far the most common primary tumour in 52% of the cases, while it accounted for only 7% of those with a diagnosed primary. We believe that the onset of bony metastases from an occult source must initially raise the possibility of lung carcinoma. If the primary remains undetected, it appears justifiable to assume it to be in the lung, since the probability of a missed lung tumour being responsible for the metastases is high.
Résumé Les auteurs ont revu les observations de 172 malades porteurs de métastases osseuses, vus entre 1965 et 1985, afin d'apprécier l'aspect général des métastases provenant d'un cancer primitif méconnu. Chez 51 malades (30%) l'origine du cancer primitif n'avait pu être découverte lors du diagnostic de métastase osseuse. Ce groupe était à prédominance masculine, comportant un nombre élevé d'atteintes vertébrales, de compressions médullaires et de fractures pathologiques, et un taux de survie significativement plus court (P<0,1) comparativement à celui des métastases d'un cancer primitif connu. La localisation du cancer primitif a été découverte dans 33 cas (65%), la plupart du temps à l'autopsie. Le cancer du poumon était le plus fréquemment en cause (52%), alors qu'il n'était responsable que de 7% des cas quand le cancer primitif était connu. Il semble que l'apparition de métastases osseuses d'origine inconnue doive faire évoquer d'emblée la possibilité d'un cancer du poumon. Si le cancer primitif ne peut être découvert il est vraisemblable qu'il siège au niveau du poumon, la probabilité d'un cancer du poumon méconnu, responsable des métastases, étant élevée.


Presented in part at the International Symposium on Bone Metastases, Rome, Italy, June 1986  相似文献   
3.
4.
The combination of small-animal PET and MRI data provides quantitative in vivo insights into cardiac pathophysiology, integrating information on biology and morphology. We sought to determine the feasibility of PET and MRI for the quantification of ischemic injury in the rat model. METHODS: Fourteen healthy male Wistar rats were studied with 18F-FDG PET and cine MRI. Myocardial viability was determined in a transmural myocardial infarction model in 12 additional rats, using 18F-FDG PET and delayed-enhancement MRI with gadolinium-diethylenetriaminepentaacetic acid. All PET was acquired with a dedicated small-animal PET system. MRI was performed on a 1.5-T clinical tomograph with a dedicated small-animal electrocardiographic triggering device and a small surface coil. RESULTS: In normal rats, 18F-FDG uptake was homogeneous throughout the left ventricle. The lowest mean uptake of the 18F-FDG was found in the apical regions (79% +/- 6.0% of maximum) and the highest uptake was in the anterior wall (93% +/- 4.3 % of maximum). Myocardial infarct size as determined by histology correlated well with defects of glucose metabolism obtained with 18F-FDG PET (r = 0.89) and also with delayed-enhancement MRI (r = 0.91). Left ventricular ejection fraction in normal rats measured by cine MRI was 57% +/- 5.4% and decreased to 38% +/- 12.9% (P < 0.001) in the myocardial infarction model. CONCLUSION: Integrating information from small-animal PET and clinical MRI instrumentation allows for the quantitative assessment of cardiac function and infarct size in the rat model. The MRI measurements of scar can be complemented by metabolic imaging, addressing the extent and severity of ischemic injury and providing endpoints for therapeutic interventions.  相似文献   
5.
The effect of hydroxyethyl starch on pancreas preservation with cardioplegic histidine-tryptophan-ketoglutarate solution (HTK) was investigated. The study was performed using an in vitro reperfusion system of the porcine pancreas. During organ preservation pancreatic weight, arterial pressure, volume flow, and washout of amylase and lactate were quantified. Addition of hydroxyethyl starch did not affect arteriovenous volume flow or washout of amylase and lactate during protective perfusion after pancreas preparation. However, hydroxyethyl starch in HTK prevented an increase in pancreatic weight at the end of the protective perfusion (102.2 ± 4.55% vs 127.8 ± 4.62% in controls; p < 0.005) and after 24 h cold ischemia (72.9 ± 3.91 % vs. 83.5 ± 3.49 % in controls; p < 0.05). Hydroxyethyl starch did not affect postischemic organ quality assessed during reperfusion in a perfusion chamber by pancreatic vascular resistance, amylase and lactate release, insulin secretion, and oxygen consumption. We conclude that hydroxyethyl starch does not bring about any further improvement in immediate postischemic organ quality assessed in an in vitro reperfusion system.
Hydroxyäthylstärke bringt keine verbesserung der pankreaskonservierung mit HTK-Lösung
Zusammenfassung Der Effekt von Hydroxyäthylstärke auf die Pankreaskonservierung mit der kardioplegischen Histidin-Tryptophan-Ketoglutarat-Lösung (HTK) wurde untersucht. Die Studie wurde an einem Reperfusionssystem des in vitro perfundierten Pankreas vom Schwein durchgeführt. Während der Organprotektion wurden das Pankreasgewicht, der arterielle Perfusionsdruck, die Volumenstromstärke sowie Amylase und Laktat im Perfusat bestimmt. Der Zusatz von Hydroxyäthylstärke bewirkte keine Änderung der Volumenstromstärke oder der Amylase- und Laktatauswaschung aus dem Organ während der Protektion. Allerdings konnte eine Zunahme des Organgewichts am Ende der protektiven Perfusion (102,2 ± 4,55% vs. 127,8 ± 4,62%in Kontrollen; p < 0,005) und nach 24 h kalter Ischamie (72,9 ± 3,91 vs. 83,5 ± 3,49% in Kontrollen; p < 0,05) durch Hydroxyathylstärke in der HTK-Lösung verhindert werden. Hydroxyäthylstärke hatte keinen Einfluß auf die postischämische Organqualität, die während der Reperfusion in einer Perfusionskammer anhand von Gefäßwiderstand, Amylase- und Laktatfreisetzung, Insulinsekretion und Sauerstoffverbrauch abgeschätzt wurde. Wir schließen daraus, daß Hydroxyäthylstärke die sofort nach einer Ischämie in einem In-vitro-Reperfusionssystem bestimmte Pankreasfunktion nicht weiter verbessert.
  相似文献   
6.
Ultrasound screening for hip dysplasia in neonates   总被引:3,自引:0,他引:3  
In a pilot study, hip development in 615 newborn children was assessed sonographically. Distinct dysplasia was found in 2.3%, and an intermediate "physiologically immature" hip development was noted in 13%. The number of controls and expenses would greatly increase if all physiologically immature hips were followed until they reached maturity. To reduce the number of unnecessary control and to facilitate assessment, we propose the use of "cut-off values" in a screening program for newborns.  相似文献   
7.
BACKGROUND: Black patients with heart failure have a poorer prognosis than white patients, a difference that has not been adequately explained. Whether racial differences in the response to drug treatment contribute to differences in outcome is unclear. To address this issue, we pooled and analyzed data from the Studies of Left Ventricular Dysfunction (SOLVD) prevention and treatment trials, two large, randomized trials comparing enalapril with placebo in patients with left ventricular dysfunction. METHODS: We used a matched-cohort design in which up to four white patients were matched with each black patient according to trial, treatment assignment, sex, left ventricular ejection fraction, and age. A total of 1196 white patients (580 from the prevention trial and 616 from the treatment trial) were matched with 800 black patients (404 from the prevention trial and 396 from the treatment trial). The average duration of follow-up was 35 months in the prevention trial and 33 months in the treatment trial. RESULTS: The black patients and the matched white patients had similar demographic and clinical characteristics, but the black patients had higher rates of death from any cause (12.2 vs. 9.7 per 100 person-years) and of hospitalization for heart failure (13.2 vs. 7.7 per 100 person-years). Despite similar doses of drug in the two groups, enalapril therapy, as compared with placebo, was associated with a 44 percent reduction (95 percent confidence interval, 27 to 57 percent) in the risk of hospitalization for heart failure among the white patients (P<0.001) but with no significant reduction among black patients (P=0.74). At one year, enalapril therapy was associated with significant reductions from base line in systolic blood pressure (by a mean [+/-SD] of 5.0+/-17.1 mm Hg) and diastolic blood pressure (3.6+/-10.6 mm Hg) among the white patients, but not among the black patients. No significant change in the risk of death was observed in association with enalapril therapy in either group. CONCLUSIONS: Enalapril therapy is associated with a significant reduction in the risk of hospitalization for heart failure among white patients with left ventricular dysfunction, but not among similar black patients. This finding underscores the need for additional research on the efficacy of therapies for heart failure in black patients.  相似文献   
8.
Zusammenfassung Mit Krebs-Ringerlösung durchströmte Rattenherzen geben um so weniger Kreatin an die Durchströmungsflüssigkeit ab, je schonender sie präpariert wurden.Nach Zugabe von 3 mg bzw. 5 mg Kreatin zu 100 ml Durchstrom nahmen die meisten Herzen innerhalb von 30 min 400 bzw. 830 Kreatin/g Trockengewicht auf. Weitere Steigerung des Kreatinangebotes verbesserte die Kreatinaufnahme nicht, ebensowenig wie Zugabe von Glucose. Enthielt der Durchstrom Insulin, so wurde die Kreatinaufnahme signifikant erhöht.Die Mehrzahl der mit Kreatin durchströmten Herzen nahm aus der Krebs-Ringerlösung Phosphat auf.Kalium wurde von einigen Herzen abgegeben, von anderen aufgenommen. Die Kaliumaufnahme aus dem Durchstrom war bei geschädigten Herzen am größten. Zusammenhänge zwischen dem Verhalten von Kalium einerseits und Kreatin oder Phosphat andererseits wurden in den Versuchen an isolierten Herzen nicht erkennbar.
Summary Rat hearts perfused with Krebs' Ringer solution, yielded creatine in the perfusion fluid; the more carefully the hearts were dissected, the smaller was the yield.When creatine was added to the perfusion fluid in concentrations of 3 or 5 mg-%, the hearts took up creatine in most cases to the extent of 400g or 830µg respectively, per g dry weight. A further increase in the creatine concentration did not improve the creatine uptake, nor did an addition of glucose to the perfusion fluid. When the latter contained insulin, the creatine uptake was significantly increased.The majority of the creatine-perfused hearts took up phosphate from the Krebs' Ringer solution.During perfusion some of the hearts yielded potassium, others took up potassium. The potassium uptake was greatest with hearts which had been damaged during the dissection. No connection could be observed in the experiments with isolated hearts between the behaviour of potassium on the one hand, and that of creatine or phosphate on the other.


Ausgeführt mit Unterstützung des Landes Nordrhein-Westfalen (Landesamt für Forschung).

Herrn Prof. Dr.E. Lehnartz zum 65. Geburtstag.  相似文献   
9.
On waiting lists, transplant candidates are routinely screened for potentially harmful complement-fixing alloantibodies using complement-dependent cytotoxicity (CDC) panel-reactive antibody (PRA) testing. We have recently developed a novel cell-independent assay for assessment of complement-activating panel reactivity ([C4d]FlowPRA), which is based on selective flow-cytometric detection of alloantibody-triggered C4 complement split product deposition to human leukocyte antigen (HLA)-coated FlowPRA beads. Serum specimens selected from 120 transplant candidates were evaluated by [C4d]FlowPRA (HLA class I vs II) in comparison with FlowPRA IgG alloantibody screening (HLA class I vs II), a method detecting both complement- and noncomplement-activating alloantibodies, and with CDC-PRA on separated T (T-CDC) or B cells (B-CDC, evaluation on platelet-absorbed sera). For each assay, >/=10% PRA reactivity was considered positive. Comparing complement-dependent PRA assays with standard FlowPRA, the specificity calculated for [C4d]FlowPRA (HLA class I: 92%; class II: 100%) was found to be superior to that of CDC testing (T-CDC-PRA: 79%; B-CDC-PRA: 86%). Because noncomplement-activating alloreactivities were not detected for both techniques, low sensitivities were calculated ([C4d]FlowPRA HLA class I: 61%; class II: 31%; T-CDC-PRA: 70%; B-CDC-PRA: 55%). Compared with CDC-PRA, [C4d]FlowPRA gave a high specificity (HLA class I compared with T-CDC: 89%, HLA class II compared with B-CDC: 95%) but, at least in part because of false-positive CDC results, a modest sensitivity (66% and 38%, respectively). For both HLA classes, we found a highly significant association between absolute [C4d]FlowPRA and CDC-PRA levels (p < 0.0001). Our results suggest that detection of C4 split product deposition to FlowPRA beads may represent an attractive HLA-specific and time-effective alternative to CDC-PRA screening.  相似文献   
10.
Endothelial damage, impaired microvascularization and immune maladaptation have been described as aetiological factors in recurrent miscarriages. We investigated the relationship between idiopathic recurrent miscarriage (IRM) and a (GT)(n) repeat microsatellite polymorphism of the gene encoding haem oxygenase 1 (HO-1), known to modulate immune functions such as T-helper (TH) cell function and to be associated with cardiovascular disease. We investigated 162 women with IRM and 129 healthy, post-menopausal controls. The length of the HO-1 (GT)(n) microsatellite was assessed by PCR and direct sequencing in all women. Results were correlated with clinical data. The distribution of genotypes was in Hardy-Weinberg equilibrium. The HO-1 (GT)(n) microsatellite repeat numbers ranged from 13 to 37, with (GT)(23) and (GT)(30) being the most common alleles in both groups. We compared alleles consisting of < or =27 GT repeats, termed class S (short) alleles and alleles consisting of >28 GT repeats, termed class L (long) alleles. Seventy per cent of women with IRM had an S allele either in heterozygous (L/S) or homozygous (S/S) form, compared to 56% of controls (P = 0.02; OR 0.54; 95% CI 0.32-0.90). With respect to S allele frequencies, we found no significant difference among women with IRM and controls [P = 0.3; odds ratio (OR) 1.23, 95% confidence interval (CI) 0.86-1.76]. Comparing women with primary and secondary IRM, no difference with respect to the length of the HO-1 (GT)(n) microsatellite was ascertained. In summary, this is the first report on a HO-1 (GT)(n) microsatellite polymorphism among women with IRM, demonstrating that the investigated polymorphism is associated with IRM in a relatively large Caucasian population.  相似文献   
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