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101.
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
102.
103.
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
104.
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
105.
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
106.
107.
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
108.
We measured umbilical cord aldosterone concentrations in 64 premature newborn infants. The median serum aldosterone level was 74.5 ngdl-1 (range 22-280 ng dl-1 ). Of the studied perinatal factors, only gestational age and birthweight presented a significant influence on the umbilical cord aldosterone levels. Newborn infants with a gestational age of over 34 weeks and a birthweight of over 2000 g had a significantly higher aldosterone cord level than those aged 34 weeks or younger and 2000 g or less in weight. 相似文献
109.
REILLY M; CONNOLLY S; STACK J; MARTIN EA; HUTCHINSON M 《QJM : monthly journal of the Association of Physicians》1992,82(1):63-70
Six patients with bilateral paramedian thalamic infarction wereseen in a general hospital over a 4 year period. This distinctstroke syndrome was recognized by the features of disturbedvigilance, often episodic, with vertical gaze disorder. Othersigns included an amnesic syndrome, convergence difficulty,third nerve palsies, eyelid retraction, dysarthria, ataxia andinvoluntary limb movements. Diagnosis was confirmed by CT brainscan or magnetic resonance imaging. A variety of risk factorsfor stroke were present. All patients improved but two had significantresidual disabilities. 相似文献
110.