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101.
Disease outcome in persons infected with Schistosoma haematobium varies dramatically, ranging from mild symptoms to severe damage of the kidneys and/or bladder. We used ultrasonography to characterize the extent of urinary tract pathology of infected children in Zimbabwe, and random genetic markers to examine the relationship between genetic diversity of S. haematobium and clinical outcome. One hundred thirty-three parasite isolates from 12 students with mild lesions and 13 with severe lesions were compared. Using four randomly amplified polymorphic DNA (RAPD) markers, we scored parasite allelic frequencies at 53 loci. Although parasite heterogeneity did not differ, allelic frequencies at eight loci differed significantly between the mild and severe groups. Parasite isolates were analyzed further using a modified cluster analysis that segregated the population into 13 clusters of associated genotypes. Three clusters were significantly over-represented in children with severe lesions. Our findings, although preliminary, suggest that parasite genetic associations may be important in clinical outcome.  相似文献   
102.
103.
(n-3) Fatty acids may reduce the risk of sudden death by preventing life-threatening cardiac arrhythmia. A standard electrocardiogram (ECG) may be used to detect clues as to the mechanism by which (n-3) fatty acids affect the electrophysiology of the heart. An earlier study showed that (n-3) fatty acids decreased the duration of the heart-rate corrected QT interval (QTc) in dogs. However, effects of (n-3) fatty acids on the standard ECG of humans have not been reported. Therefore, we investigated the effect of (n-3) fatty acids on QTc, QRS duration, apex-to-end-T duration, T-loop morphology and spatial QRS-T angle in apparently healthy men and women aged 50 to 70 y. Subjects (n = 42/group) received either capsules providing 1.5 g (n-3) fatty acids daily or placebo for 12 wk. ECG were recorded before and after intervention. None of the ECG characteristics were affected by (n-3) fatty acids. The QTc decreased by 0.8 ms or 0.2% (95% confidence interval, -6.1 to 4.4 ms) in subjects that consumed (n-3) fatty acids compared with the placebo group. These results do not support the hypothesis that (n-3) fatty acids prevent arrhythmia through electrophysiologic effects on heart cell membranes. However, an effect on the ECG in more susceptible populations can not be excluded.  相似文献   
104.
A systematic consideration of the cost-effectiveness in decisions concerning the financing and implementation of healthcare technologies would contribute to the efficiency of the Dutch healthcare system. This consideration applies to the initial decision to finance a project, the periodic testing of this on the basis of practice data and the policy to promote a cost-effective approach in daily practice (via practice guidelines). Bearing in mind that the government has decided to allocate few additional resources to healthcare, it should undertake measures to ensure the systematic use of such information in these steps. The National Institute for Clinical Excellence (NICE) in the United Kingdom can serve as an example, where broadly supported guidelines are drawn up with systematic attention for the cost-effectiveness and the implications for healthcare. Within this context the question arises as to whether a Dutch variant of NICE is needed.  相似文献   
105.
Objective: To assess the quality of life of 384 Dutch children aged 1–7 years with recurrent acute otitis media (AOM), and compare it with that of children from four reference populations: (i) children from a general population; (ii) children with mild‐to‐moderate asthma, (iii) children with mild‐to‐moderately severe chronic illness, and (iv) US children with persistent or recurrent otitis media. Design: Survey. Setting: A general and an academic hospital (study population of children with recurrent AOM, n = 384); general population (n = 225 and 117); primary care (children with asthma, n = 64); community care (children with chronic illness, n = 82); and a general hospital (children with persistent or recurrent otitis media, n = 169). Participants: A total of 384 children aged 1–7 years who had experienced at least two episodes of AOM in the preceding year and their caregivers. Main outcome measures: Generic and disease‐specific quality of life as judged by the children's caregivers. Age‐adjusted total and subscale scores were compared with those of the reference populations. Results: For all generic questionnaires, children with recurrent AOM had poorer scores than children from the general population. Quality of life of children with four or more episodes of AOM in the preceding year was poorer than that of children with two to three episodes. Children with recurrent AOM scored lower on the health‐related questionnaire than children with mild‐to‐moderately severe chronic illness. Quality of life of the present study population was similar to those of children with asthma and US children with chronic otitis media with effusion or recurrent AOM. Conclusion: Recurrent AOM has a considerable negative impact on the quality of life of children and causes concern to their caregivers. These effects are proportional to the severity of the condition. Professionals involved in the care of children with OM should be aware that OM not only affects physical functioning but also general well‐being of the child and its family. These outcomes should therefore be included in the evaluation of the child with otitis media both in the clinical and research setting.  相似文献   
106.
Benign familial infantile convulsions (BFIC) is a recently identified partial epilepsy syndrome with onset between 3 and 12 months of age. We describe the clinical characteristics and outcome of 43 patients with BFIC from six Dutch families and one Dutch-Canadian family and the encountered difficulties in classifying the syndrome. Four families had a pure BFIC phenotype; in two families BFIC was accompanied by paroxysmal kinesigenic dyskinesias; in one family BFIC was associated with later onset focal epilepsy in older generations. Onset of seizures was between 6 weeks and 10 months, and seizures remitted before the age of 3 years in all patients with BFIC. In all, 29 (67%) of the 43 patients had been treated with anti-epileptic drugs for a certain period of time. BFIC is often not recognized as (hereditary) epilepsy by the treating physician. Seizures often remit shortly after the start of anti-epileptic drugs but, because of the benign course of the syndrome and the spontaneous remission of seizures, patients with low seizure frequency do not necessarily have to be treated. If prescribed, anti-epileptic drugs can probably be withdrawn after 1 or 2 years of seizure freedom.  相似文献   
107.
OBJECTIVE: To determine how the mortality and morbidity after aortocoronary bypass surgery during the hospital stay correspond with those in the first 6 months after the operation. DESIGN: Prospective and retrospective. METHOD: Data of 563 patients undergoing isolated myocardial revascularization in 1998 in the Academic Hospital Nijmegen, the Netherlands, were collected on mortality and morbidity 180 days after the operation. The Parsonnet score was used to assess the operative risk of the patients. RESULTS: The patient group consisted of 422 males and 141 females, with a mean age of 64.3 years. The median Parsonnet score was 6 (range: 0-50). The mean hospital stay was 7.9 days (SD: 9.4). The hospital mortality was 3.9% (22/563). The follow-up was 100%. During the follow-up 11 patients died, 10 from cardiac causes. Six months postoperatively the mortality was 5.9% (22/563). The Kaplan-Meier curve of the survival probability rate showed a persistent decrease, mainly in the higher risk patients. Non-fatal cardiovascular events were registered in 9.6% of the surviving patients (51/530). CONCLUSION: The hospital mortality and morbidity after aortocoronary bypass surgery were considerably lower than the total postoperative mortality and morbidity during the first 6 months after the operation. For assessment of the postoperative course, systematic follow-up over 6 months is necessary.  相似文献   
108.
109.
Polymeric catalysts consisting of cobalt(II)phthalocyanine, CoPc(NaSO3)4, coordinatively bound to poly(vinylamine) of various molecular weight, were used as oxidation catalysts in the conversion of thiols to disulfides. The molecular weight of the polymeric ligand, poly(vinylamine), largely affects the reaction rate below a critical polymer concentration of about 0,01 w/v%. The activation enthalpy ΔH does not depend on the degree of polymerization (DP) of the polymeric ligand and from visible light spectra it appears that electron transfer of the thiolanion to Co(II) to yield Co(I) is favored when low instead of high molecular weight ligands are used. The observed catalytic oxidation rate of thiol is considerably higher for low molecular weight ligands (DP 20 – 40) in the low polymer concentration region. This may be attributed to a change in base strength in the micro-environment of CoPc(NaSO3)4 due to conformational differences between low and high molecular weight ligands, manifested at low polymer concentration. When the ligand has no polymeric character, e. g. 1, 3-propanediamine, low catalytic activity is observed.  相似文献   
110.
BACKGROUND: Increasing life expectancy and decreasing marginal valuation of additional QALYs over time may serve as a basis for discounting future health effects from a societal perspective. Therefore, we tested the hypothesis that societal time preference for health is related to perceived future life expectancy. METHODS: A sample of 223 people from the general population prioritised healthcare programmes with differential timing of health benefits and costs from a societal perspective. Furthermore, we asked respondents to estimate future life expectancy. RESULTS: The relationship between future life expectancy and time preference for health is ambiguous. We observed that people who expected a higher future life expectancy elicited higher discount rates for health effects than those with lower life expectancy growth expectations for all four time periods (5, 10, 20 and 40 years into the future), but the differences were never significant. On average, providing explicit information on growth in life expectancy did significantly alter discount rates in the expected direction but, on an individual level, the results were rather inconsistent. We observed a significantly stronger time preference (i.e. higher discount rates) for health effects than for costs. As commonly observed, discount rates for health and money decreased with time delay following a hyperbolic function. CONCLUSION: Our data indicate that it is troublesome to elicit societal discount rates empirically, especially rates that are in line with the theoretical arguments on societal discounting. The influence of life expectancy remains ambiguous, but there seems to be at least some positive relationship between growth in life expectancy and discount rates that deserves additional attention.  相似文献   
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