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排序方式: 共有514条查询结果,搜索用时 15 毫秒
101.
A C van Houwelingen A A Hennissen F Verbeek-Schippers T Simonsen A D Kester G Hornstra 《Thrombosis and haemostasis》1988,59(3):507-513
This paper describes the results of an international study to investigate the effect of a reasonable amount of dietary fish on platelet aggregation in platelet-rich plasma (PRP) induced by collagen and thrombin. In Maastricht, Troms?, and Zeist two groups of healthy male volunteers were given a daily dietary supplement consisting of 135 g of canned mackerel paste (experimental group, n = 40) or meat paste (control group, n = 42) for a 6-week period. Compliance, calculated on the basis of the urinary excretion of lithium, added to the supplements, was about 80%. Platelet number in PRP decreased significantly in the fish group. Collagen-induced platelet aggregation in PRP differed widely between the three centres despite the attempt to use exactly the same conditions. Nonetheless, aggregation decreased significantly in the fish group. The mackerel effect on thrombin-induced aggregation was inconsistent. 相似文献
102.
Sequelae in long-term survivors of small cell lung cancer 总被引:5,自引:0,他引:5
103.
Comparison between habitual intake of polyunsaturated fatty acids and their concentrations in serum lipid fractions 总被引:1,自引:0,他引:1
A C von Houwelingen A D Kester D Kromhout G Hornstra 《European journal of clinical nutrition》1989,43(1):11-20
To evaluate the validity of the cross-check dietary history method for the assessment of the habitual intake of polyunsaturated fatty acids, the relationship was investigated between the estimated intake of these fatty acids and their relative amounts in the various serum lipid fractions. Food intake data were obtained from a group of volunteers participating in a long-term epidemiological study in the Dutch town of Zutphen. The fatty acid composition of total lipids, phospholipids, triglycerides and cholesterol esters was determined in fasting serum samples from these volunteers. Although correlations between the calculated dietary intake of timnodonic acid (20:5(n-3), TA) and cervonic acid (22:6(n-3), CA), on the one hand, and the relative amounts of these fatty acids in the various serum lipid fractions, on the other, appeared to be statistically significant, no more than about 20 per cent of the variance in the serum values could be explained on the basis of dietary intake. For linoleic acid (18:2(n-6), LA) this was 55 per cent. It is concluded that the cross-check dietary history method is an acceptable technique for estimating the habitual intake of linoleic acid of a given individual. For the fish-related fatty acids, however, this method is less reliable. This discrepancy most probably results from the large differences in TA and CA contents in the same foods. In addition, a negative association with the calculated LA intake on the proportional amount of TA for most of the serum lipid fractions was demonstrated. This indicates an interference of dietary LA on the metabolism of TA. 相似文献
104.
A D Muller A C van Houwelingen M C van Dam-Mieras B M Bas G Hornstra 《Thrombosis and haemostasis》1989,61(3):468-473
This article describes the results of a dietary intervention study performed in three different centers. In the study the effect of a diet enriched with fish on the coagulation tendency of blood was investigated. Two groups of 40 volunteers were given a dietary supplement consisting of 135 g of canned mackerel or meat paste (control) for a 6 weeks period. Compliance, monitored by measuring the urinary excretion of lithium, added to the supplements, was about 80%. Before, during and at the end of the experimental period a number of hemostatic parameters, reflecting the coagulation tendency of blood and the procoagulant activity of monocytes, were measured. The fish supplement did not cause a significant effect on the prothrombin time and on the levels of factor VII, activated factor VII, antithrombin III, von Willebrand factor, fibrinogen, plasminogen and alpha 2-antiplasmin. A slight but transient prolongation in the activated partial thromboplastin time was observed as well as a significant increase in the factor X level, which became more pronounced with prolongation of the experimental period; no activated factor X was found. A tendency towards a stimulation of monocyte procoagulant activity was noticed. 相似文献
105.
G Hornstra 《Wiener klinische Wochenschrift》1989,101(8):272-277
In rats, diets rich in polyunsaturated fatty acids of the (n-6) and (n-3) families (P) lower arterial thrombosis tendency, whereas long-chain saturated fatty acids (S) are prothrombotic. Monounsaturated fatty acids seem to behave neutrally as to arterial thrombus formation. Consequently, the P/S ratio is an important determinant of the thrombogenicity of a dietary fat, the effect of which is probably mediated by an influence on platelet aggregability. In man, the dietary fat type also affects platelet aggregation. Methodological problems, however, resulted in equivocal results, especially with respect to diets enriched with fish oil. Thus, more research is required with methods that are able to quantify thrombotic risk in a reliable way. Nonetheless, the available evidence already justifies an active policy to increase the consumption of (poly)unsaturated fatty acids at the expense of long-chain saturated fatty acids. 相似文献
106.
Preliminary studies indicated that the EFA status of normal neonates is marginal, if not insufficient. Since a better knowledge of the physiology of maternal-fetal essential fatty acid transfer is relevant for nutritional recommendations during pregnancy, we investigated the course of the fetal EFA status during fetal development by analysing the absolute (micrograms/g dry fetal tissue) and relative (% of total fatty acids) fatty acid composition of phospholipids in human fetal tissue, (n = 40, gestational age 5-15.2 weeks). The total content of fatty acids (mg/g dry fetal tissue) increased with gestational age. The absolute amount of virtually all fatty acids increased with maturation. Linoleic acid (18:2n-6, LA), however, was an exception. A highly significant, negative correlation between gestational age and the relative amount of LA in fetal tissue was observed during this first trimester of pregnancy. Our results show that the fetal-maternal difference in linoleic acid content observed at birth, initiates early in pregnancy. Since the fetus completely depends on the mother for its EFA supply, the maternal EFA status was measured simultaneously by analysing the fatty acid composition of phospholipids, isolated from plasma and red blood cells. Significant positive correlations between maternal rbc and fetal tissue were found for the relative amounts of LA. Similar relationships were observed between maternal plasma and fetal tissue for the relative amounts of cervonic acid (22:6n-3), the most abundant essential fatty acid in brain and retina. The relation between maternal and fetal EFA in phospholipids is significantly more pronounced after 10 weeks of gestation than before. This might be connected with the increased importance of the placenta with respect to maternal-fetal fatty acid transfer after 10 weeks of gestation. 相似文献
107.
Petra Braaksma Ilse Stuive Rianne Garst Carlijn F. Wesselink Corry K. van der Sluis Rienk Dekker Marina M. Schoemaker 《Journal of Science and Medicine in Sport》2018,21(3):296-306
Objectives
To examine the characteristics of physical activity (PA) interventions and the effects on cardiorespiratory fitness (CRF) in healthy children based on treatment theory.Design
Systematic review.Methods
PubMed and Embase were searched for studies published between 2003 and 2016.Inclusion criteria were:Participants: healthy children aged 6–12.Interventions: interventions with activities to increase PA behaviour or physical fitness (PF) regardless of setting.Control: no or alternative intervention.Outcome: exercise-based CRF measure with appropriate analysis of CRF effects.Study design: randomized controlled trial.Effect size was calculated using dppc2 and the methodological quality of the studies was assessed using the PEDro scale.Results
Of 1002 studies screened, 23 met the inclusion criteria. Thirteen of the 23 studies found statistically significant improvements in CRF and eight studies showed medium to high effect sizes. Interventions with medium to high effect sizes focused more often on PF than PA behaviour, had slightly higher frequencies of activities and had a shorter duration than the less effective interventions.Conclusions
The fact that thirteen studies demonstrated statistically significant improvements in CRF is promising but also emphasizes the need to keep improving research methods and the development and execution of interventions. Interventions with larger effect sizes appear to be more controlled, as they usually relied on smaller sample sizes and the components of these interventions encompassed protocolled training sessions which defined and monitored the relative training intensity intended. A duration of at least six weeks and a frequency of three to four times a week is recommended. 相似文献108.
The ultrastructure of hamster bronchial epithelium 总被引:2,自引:0,他引:2
T G Christensen R Breuer L J Hornstra E C Lucey G L Snider 《Experimental lung research》1987,13(3):253-277
The central intrapulmonary bronchi of adult male Syrian hamsters were examined by electron microscopy to identify the principal types and proportions of epithelial cells. A differential count of cells displaying both a basal lamina and luminal border (transepithelial cells) showed that, on average, ciliated cells constituted 63% and granule-containing (granulated) secretory cells 25% of the total. Other transepithelial cells included nongranulated secretory cells (9%), preciliated cells (1.5%), and indeterminate cells (1%). The most frequent granulated secretory cell (77% of the population) was the Clara cell. It was identified by the presence of prominent apical smooth endoplasmic reticulum and secretory granules. It was subclassified into three types based on the presence or absence of rough endoplasmic reticulum and on granule morphology. Mucous cells (little or no smooth endoplasmic reticulum but with typical mucous granules) constituted approximately 20% of the granulated secretory cells. Serous cells were very infrequent. A differential count of nucleated epithelial cells demonstrated an average of 2% basal cells (hemidesmosomes present) and 20% pseudobasal cells (hemidesmosomes absent). Neuroepithelial bodies and solitary "small-granule" cells were infrequent. Brush cells and apoptotic bodies were rarely found but are noteworthy because their occurrence in hamster airways was not demonstrated previously. These results provide a foundation for subsequent analysis of alterations of epithelial homeostasis induced by injurious agents of exogenous and endogenous origin. 相似文献
109.
110.