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101.
102.
HPM Smedts JH de Vries M Rakhshandehroo MF Wildhagen AC Verkleij-Hagoort EA Steegers RPM Steegers-Theunissen 《BJOG : an international journal of obstetrics and gynaecology》2009,116(3):416-423
Objective To study associations between maternal dietary and supplement intake of antioxidants vitamin E, retinol and congenital heart defects (CHDs).
Design Case–control study.
Setting Erasmus MC, University Medical Center Rotterdam, the Netherlands.
Population Participants were 276 case mothers of a child with CHD and 324 control mothers with their children.
Methods Food frequency questionnaires covering the intake of the previous 4 weeks were filled out at 16 months after the index pregnancy. Data were compared between cases and controls using the Mann–Whitney U test. Risk estimates for the association between CHD and dietary intake of vitamin E and retinol were estimated in a multivariable logistic regression model.
Main outcome measures Medians (5–95th percentile) and odds ratios with 95% CI.
Results Dietary vitamin E intake was higher in case mothers than in controls, 13.3 (8.1–20.4) and 12.6 (8.5–19.8) mg/day ( P = 0.05). CHD risk increased with rising dietary vitamin E intakes ( P -trend = 0.01). Periconception use of vitamin E supplements in addition to a high dietary vitamin E intake above 14.9 mg/day up to nine-fold increased CHD risk. Retinol intakes were not significantly different between the groups and not associated with CHD risk.
Conclusions High maternal vitamin E by diet and supplements is associated with an increased risk of CHD offspring. 相似文献
Design Case–control study.
Setting Erasmus MC, University Medical Center Rotterdam, the Netherlands.
Population Participants were 276 case mothers of a child with CHD and 324 control mothers with their children.
Methods Food frequency questionnaires covering the intake of the previous 4 weeks were filled out at 16 months after the index pregnancy. Data were compared between cases and controls using the Mann–Whitney U test. Risk estimates for the association between CHD and dietary intake of vitamin E and retinol were estimated in a multivariable logistic regression model.
Main outcome measures Medians (5–95th percentile) and odds ratios with 95% CI.
Results Dietary vitamin E intake was higher in case mothers than in controls, 13.3 (8.1–20.4) and 12.6 (8.5–19.8) mg/day ( P = 0.05). CHD risk increased with rising dietary vitamin E intakes ( P -trend = 0.01). Periconception use of vitamin E supplements in addition to a high dietary vitamin E intake above 14.9 mg/day up to nine-fold increased CHD risk. Retinol intakes were not significantly different between the groups and not associated with CHD risk.
Conclusions High maternal vitamin E by diet and supplements is associated with an increased risk of CHD offspring. 相似文献
103.
Legendre C; Raphael M; Gras G; Lefevre EA; Feuillard J; Dormont D; Richard Y 《International immunology》1998,10(12):1847-1851
A centrofollicular hyperplasia is present within secondary lymphoid organs
during all the asymptomatic phase of the HIV disease. Although this
hyperplasia has been well characterized by histological studies, the nature
of the phenotypic alterations in B cell populations occurring within HIV+
lymphoid organs remains to be established. By immunohistochemistry, we thus
investigated whether a particular germinal center (GC) B cell population
was increased during HIV-induced hyperplasia and whether any phenotypic
change was specific to HIV-1 infection. As compared to normal tonsils
(three cases) and HIV- hyperplastic lymph nodes (eight patients), we
observed a loss of GC polarization in all HIV+ sections (11 patients), with
no more delineation between dark and light zones, as shown by Ki67, CD10,
CD77, CD95 and CD86 staining. In contrast to CD86 expression which remained
as intensive in HIV+ as in HIV- lymph nodes, CD80 staining was strongly
decreased in GC of HIV+ lymph nodes but not in their extrafollicular zones.
The loss of CD80 expression from CD19+ B cells was also observed by
cytometric analysis of cell suspensions of three HIV+ patients. Although we
found no evidence of an increase in a particular GC B cell subset in
HIV-1-induced hyperplasia, the strong GC disorganization observed may
induce impaired cell-cell interactions and thus participate in the loss of
CD80 antigen. In contrast to HIV- situations where CD80 and CD86 was
similarly expressed on B cells, the lower level of CD80 expression in HIV+
GC may favor Th2 T cell responses through CD86-CD28 interactions.
相似文献
104.
Between January and March 1986, 117 wives of insulation workers exposed to asbestos were screened by means of chest radiography, pulmonary function testing, and a detailed questionnaire. The final study group included 93 women over 40 years of age. Eighteen of these (19.4%) demonstrated pleural changes consistent with asbestos exposure, including pleural plaque (88.9%), diaphragm plaque (27.8%), pleural calcification (16.6%), and diffuse pleural thickening (5.5%). In statistical correlation between the groups with normal and abnormal radiographs, the only factor that proved significant was the year of first exposure (the duration of the latent period). Finally, radiographs of the husbands were compared for 17 of the 18 wives with radiographic abnormalities. Fourteen of the husbands (82%) demonstrated more severe radiographic changes than their wives. 相似文献
105.
106.
Shape and dimensions of cardiac chambers: importance of CT section thickness and orientation 总被引:2,自引:0,他引:2
Three-dimensional (3D) computed tomography (CT) scan data were used to quantitate the geometry of all heart chambers. The Dynamic Spatial Reconstructor (DSR) was used to scan dogs with in situ casts of the cardiac chambers. Chamber volumes estimated from DSR images were accurate within 5% of water displacement volume measurements of the actual casts for chambers greater than 11 ml and within 10% of water displacement volumes for chambers less than 11 ml. Anatomic features of the actual cast correlated closely with anatomy visible in computer-generated surface images of the 3D DSR image data. The important effect of reconstructed section thickness and orientation on the fidelity of 3D cardiac geometry is demonstrated. 相似文献
107.
ES2 is a gene deleted in DiGeorge syndrome (DGS) and velocardiofacial
syndrome (VCFS) which has homologs in species as distant as Caenorhabditis
elegans and Drosophila . The function of ES2 is unknown, and the predicted
protein sequence does not contain motifs which suggest a particular role in
the developmental defects present in DGS and VCFS. Here we show that the
mouse homolog, Es2 , is transcribed in two forms resulting from the use of
alternative polyadenylation signals. Structural analysis programs predict
that the Es2 -encoded peptide has a coiled-coil domain, and transfection
experiments with an Es2 -green fluorescent protein (GFP) fusion construct
show that the peptide is recruited into the nucleus. Es2 is highly
expressed during mouse embryogenesis from E7 onwards. In situ hybridization
with an RNA probe revealed that the gene is widely expressed; however,
relatively higher expression was detected in the nervous system, with a
particularly high area of expression in a sub-region of the pons. The Es2
expression domain in the pons is shared with a Goosecoid-like gene ( Gscl)
which is located upstream of Es2 , and raises the possibility that the two
genes share regulatory elements and/or interact in this region of the
developing brain. This finding suggests that different genes in the deleted
region may be functionally related and might explain the occurrence of the
characteristic phenotype in patients with non-overlapping genetic lesions.
相似文献
108.
The H1-histaminergic agonists 2-pyridylethylamine (2-PEA) and 2-methylhistamine relaxed potassium-constricted, perfused, rabbit middle cerebral arteries at low concentrations (3 x 10(-11) to 3 x 10(-8) M) and constricted them at high concentrations (3 x 10(-7) to 3 x 10(-4) M). The relaxation and the contraction were not antagonized by propranolol (up to 3 x 10(-6) M) given 30 min before, suggesting that beta-adrenergic mechanisms were not involved. When 2-PEA was tested on arteries constricted with uridine triphosphate (UTP), similar results were obtained. In the UTP-constricted arteries, the 2-PEA-induced responses were competitively antagonized by 3 x 10(-9) M mepyramine. Together with previous work (Ea Kim et al., 1986), these results are compatible with the hypothesis that H1-receptors were responsible for both the relaxation and the contraction observed. When either indomethacin (10(-8), 3 x 10(-7), or 10(-5) M), dexamethasone (10(-5) M), or tranylcypromine (10(-5) or 10(-4) M) were tested on the response to 2-PEA or 2-methylhistamine, these inhibitors suppressed the relaxation or reversed it to a contraction. Furthermore, they potentiated the contraction induced by these agonists. These results favour the hypothesis that the H1-mediated relaxation in rabbit cerebral arteries may in part involve the release of prostaglandins, especially prostacyclin. The participation of such a prostanoid in histaminergic relaxation seems exclusively an H1-mediated mechanism, since the relaxation induced by the H2-agonist dimaprit (in the presence of mepyramine) was not antagonized by either indomethacin (3 x 10(-7) M) or tranylcypromine (10(-4) M). 相似文献
109.
110.
In the period 1985-94, 237 out of 575 248 (0.41 per 1000) live born infants in Norway were reported to suffer culture-confirmed systemic group B streptococcal disease before their 90th day of life. The annual incidence increased from 0.20 per 1000 live births in 1985 to 0.64 in 1994, due solely to an increase in cases with an onset before the seventh day of life. Future studies should address the possible causes of this increase. 相似文献