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排序方式: 共有1059条查询结果,搜索用时 15 毫秒
61.
Ouyang Q Cicek G Westendorp RG Cools HJ van der Klis RJ Remarque EJ 《Mechanisms of ageing and development》2000,121(1-3):131-137
Cytokine interferon gamma (IFN-gamma) is pivotal in the defence against viruses and intracellular pathogens and an age-related decreased IFN-gamma production may explain the increased infectious disease morbidity and mortality in the elderly. Therefore, we performed a series of clinical experiments evaluating the influence of age and health status on IFN-gamma production following in vitro stimulation with influenza vaccine or endotoxin. Both healthy and frail elderly people produced significantly lower amounts of IFN-gamma following ex vivo stimulation with influenza vaccine or endotoxin. We conclude that ageing is accompanied by a decreased capacity to produce IFN-gamma. This may explain the increased incidence and case-fatality caused by viruses and intracellular pathogens in the elderly. 相似文献
62.
Hyperlipoproteinemia affects cytokine production in whole blood samples ex vivo. The influence of lipid-lowering therapy 总被引:1,自引:0,他引:1
Mohrschladt MF Weverling-Rijnsburger AW de Man FH Stoeken DJ Sturk A Smelt AH Westendorp RG 《Atherosclerosis》2000,150(2):413-419
A specific and robust immunoassay for the lipoprotein-associated phospholipase A2 (Lp-PLA2), platelet-activating factor acetylhydrolase, is described for the first time. The immunoassay was used to evaluate possible links between plasma Lp-PLA2 levels and atherosclerosis risk amongst susceptible individuals. Such an investigation was important because Lp-PLA2 participates in the oxidative modification of low density lipoprotein by cleaving oxidised phosphatidylcholines, generating lysophosphatidylcholine and oxidised free fatty acids. The majority of Lp-PLA2 was found associated with LDL (approximately 80%) and, as expected, enzyme levels were significantly positively correlated to LDL cholesterol. Plasma Lp-PLA2 levels were significantly elevated in patients with angiographically proven coronary artery disease (CAD) when compared with age-matched controls, even though LDL cholesterol levels did not differ significantly. Indeed, when included in a general linear model with LDL cholesterol and other risk factors, Lp-PLA2 appeared to be an independent predictor of disease status. We propose, therefore, that plasma Lp-PLA2 mass should be viewed as a potential novel risk factor for CAD that provides information related to but additional to traditional lipoprotein measurements. 相似文献
63.
Antibodies to tumor necrosis factor alpha prevent increases in cell replication in liver due to the potent peroxisome proliferator, WY- 14,643 总被引:7,自引:6,他引:7
Bojes HK; Germolec DR; Simeonova P; Bruccoleri A; Schoonhoven R; Luster MI; Thurman RG 《Carcinogenesis》1997,18(4):669-674
Several structurally dissimilar hypolipidemic drugs, plasticizers and
halogenated hydrocarbons induce peroxisomes in hepatocytes, and cause
hepatocellular adenoma and carcinoma in rats and mice. The mechanism by
which these agents act is unknown, although recent studies have suggested a
link between increased cell proliferation and hepatic cancer caused by
peroxisome proliferators. Here, we demonstrate that neutralizing antibodies
to tumor necrosis factor alpha (TNF alpha) block increases in protein
kinase C and cell proliferation due to [4-
chloro-6-(2,3-xylidino)-2-pyrimidinylthio]acetic acid (WY-14,643), a
hypolipidemic drug and potent peroxisome proliferator that causes tumors.
WY-14,643 moderately elevated the level of TNF alpha mRNA in the liver. TNF
alpha was detected immunohistochemically exclusively in Kupffer cells.
These results demonstrate that WY-14,643 acts as an indirect mitogen on
hepatocytes via TNF alpha. We propose that the Kupffer cell, a major source
of TNF alpha in the liver, is involved in the mechanism of the mitogenic
effect of WY-14,643.
相似文献
64.
Evaluation of attempted prevention of unexpected infant death in very high-risk infants by planned health care 总被引:1,自引:0,他引:1
Three hundred and ninety-six babies born in Sheffield between 1982 and 1990 identified as being at "very high risk" of unexpected infant death by means of a scoring system, received an intensive programme of health care including a case discussion between a paediatrician, the GP and the health visitor held in the family doctor's surgery, weekly visits from the health visitor and informal hospital admission. Significantly fewer sudden unexpected infant deaths occurred in this group than were expected by logistic regression anlysis or occurred in the best available control group with comparable scores ( p = 0.024). Problems in evaluation include identification of an adequate control population, ethical difficulties in introducing a controlled study when the programme is already perceived as effective, and the calculation of "expected death rates". The results of this study indicate that very energetic programmes of intervention may prevent some deaths in vulnerable infants. 相似文献
65.
PJ Fielder SE Gargosky M Vaccarello K Wilson P Cohen F Diamond J Guevara-Aguirre AL Rosenbloom RG Rosenfeld 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S389):40-43
Six adult patients with growth hormone receptor deficiency (GHRD) (2 men, 4 women) with an identical defect in the growth hormone receptor (GHR) gene, were treated with recombinant human insulin-like growth factor I (IGF-I), 40 μgikg S.C. twice daily, for 7 days. Serum concentrations of IGF peptide and IGF binding protein-3 (IGFBP-3) were measured by specific radioimmunoassays; serum IGFBPs were also measured by Western ligand blotting. The size distribution of both IGF-I and IGF-II was measured in serum following size-exclusion fast-performance liquid chromatography. IGF-I treatment resulted in a normalization of serum IGF-I levels on days 1–7 of treatment and a decrease in serum IGF-II levels. The fall in IGF-II levels and the simultaneous rise in IGF-I levels, however, resulted in an unchanged total serum IGF level. The low IGFBP-3 values did not significantly change during treatment, whereas there was a slight increase in IGFBP-2 levels. Preliminary analysis of size-fractionated sera suggested an increase in IGF-I levels in the 40 and 150 kDa regions at the expense of IGF-II levels. The results suggest that despite the failure of IGF-I treatment to increase IGFBPs significantly, serum IGFBP concentrations were sufficient to maintain normal levels of IGF-I. 0 Laron syndrome, growth hormone receptor deficiency, insulin-like growth factors, insulin-like growth factor binding protein 相似文献
66.
67.
P Miny S Basaran I H Pawlowitzki J Horst A Westendorp W Niedner W Holzgreve 《American journal of medical genetics》1989,33(1):136-141
Cytogenetic findings in the Münster Chorionic Villi Sampling (CVS) program are presented after 1,184 first trimester transcervical samplings and 131 second and third trimester placentacenteses. In the first trimester series the abnormality rate is low (2.4%) in patients with only an age-dependent aneuploidy risk. In this group terminations were performed in only 1.6% because of aneuploidy. True mosaicism was found more frequently after CVS, and the risk of maternal cell contamination seems higher as compared to amniocentesis. There are no obvious differences in the overall rate of diagnostic errors after both procedures, when metaphases after direct preparation and chorionic cell cultures are analysed and doubtful findings such as mosaicism are adequately followed up by amniocentesis. The cytogenetic techniques also offer a very rapid approach to karyotyping in the second and third trimester. We found a high rate of aneuploidy (15%) when placentacentesis was performed after sonographic diagnosis of fetal abnormalities. We conclude that cytogenetic analysis from trophoblast tissue is an accurate diagnostic tool applicable from first to third trimester of pregnancy. 相似文献
68.
69.
70.
van Bemmel T Vandenbroucke JP Westendorp RG Gussekloo J 《Journal of clinical epidemiology》2005,58(1):63-67
OBJECTIVE: The objective of this study was to explore the relationship between home hazards and the incidence of falls in the oldest old population. STUDY DESIGN AND SETTING: The Leiden 85-plus Study is a population-based study of all 85-year-old inhabitants of Leiden in the birth-cohort 1912-1914. Participants and general practitioners were interviewed at baseline and annually there after. We analyzed the incidence of falling in the first year dependent on the presence of home hazards at baseline. There were no exclusion criteria other than the inability to walk alone. RESULTS: During the 1-year follow-up, 44% of the participants experienced one or more falls. Participants without preceding falls (n=246) had a 4-fold risk for falls in the presence of six or seven home hazards (relative risk 3.58, 95% confidence interval 1.75-5.05) compared with those without home hazards. Participants with preceding falls (n=234) had no increased risk of falls with increasing numbers of home hazards, although they had a higher risk to fall. The data confirmed the known increased risk for falls in participants with physical impairments. CONCLUSION: We conclude that participants without a history of preceding falls have an increased risk of falling due to the presence of home hazards. 相似文献