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Kurt Jungermann 《Die Naturwissenschaften》1989,76(12):547-559
The liver is the glucose reservoir of the organism and moreover an important blood reservoir, which takes up or releases glucose and blood depending on demand. Activation of the sympathetic nerves increases glucose release, shifts lactate uptake to output and reduces a.o. oxygen uptake. Moreover, it elicits a reduction of blood flow, and, by closing of sinusoids, an intrahepatic redistribution as well as a mobilization of blood. Activation of parasympathetic nerves enhances glucose utilization and causes a re-opening of closed sinusoids. The actions of sympathetic nerves can be modulated by hormones. Extracellular calcium as well as the mediators noradrenaline and probably also prostaglandins are involved in the signal chain. Intracellularly the signal chain is propagated by an increase of cytosolic calcium. 相似文献
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Dr E. Vamos D. Pratola N. Van Regemorter M. Freund J. Flament-Durand F. Rodesch 《黑龙江环境通报》1985,5(3):209-214
Amniocentesis was performed in view of a paternal balanced chromosomal rearrangement t(4;20)(p16;p12), inv(18)(p11q11). The pregnancy was complicated by severe oligohydramnios. The fetal karyotype was unbalanced: 46XX, der(4), t(4;20)(p16;p12), inv(18) (p11q11)pat., thus resulting in partial trisomy 2Op and monosomy 4p. In addition, the amniotic fluid alpha-fetoprotein (AFP) became increasingly elevated with gestational age. The pregnancy was terminated at 25 weeks. The fetus presented with typical facial dysmorphic features, unilateral cleft lip and palate, severe renal hypoplasia, consistent with the 4p- (Wolf-Hirschhorn) syndrome. 相似文献
108.
Using the polymerase chain reaction (PCR), it was possible to amplify a single copy fragment of the β-globin gene from 2–32 human embryonic cells obtained from arrested preimplantation embryos. For the detection of β-thalassaemia mutations, allele specific priming of the PCR using nested primers was employed using approximately 10 pg of DN A from individuals known to carry these mutations. This approach was successful in detecting the presence or absence of five Asian Indian β-thalassaemia mutations that were selected for this study. In spite of meticulous precautions against contamination, false-positive amplification was observed, a problem that will have to be overcome before this approach can be used in clinical practice. 相似文献
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Prenatal diagnosis of 5p deletion syndrome, or cri du chat, following an abnormally low measurement of a screening of serum human chorionic gonadotrophin (hCG), is reported. Karyotyping following amniocentesis revealed a terminal deletion in the short arm of one chromosome 5. The pregnancy was electively terminated. 5p deletion syndrome has been described with abnormally high hCG levels and normal hCG levels. This is the first report of its association with abnormally low levels. The association between chromosomal abnormalities and hCG is discussed. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Ivemark syndrome with agenesis of the corpus callosum: a case report with a review of the literature
Asplenia associated with situs ambiguus, symmetric liver, bilateral trilobulated lungs, and a complex heart defect was diagnosed on autopsy in a 14-day-old infant. Furthermore, examination of the brain displayed agenesis of the corpus callosum (ACC) with pachygyria and hydrocephalus. The characteristic association of asplenia with visceroatrial heterotaxia is traditionally named after the Swedish pediatrician, Ivemark. Although exceptional, association of Ivemark syndrome with callosal agenesis has been reported recently. The concept of ‘developmental fields’ describes morphogenetically reactive units of the embryo determining and controlling the development of complex structures in a hierarchical manner. Lateralization defects such as situs inversus, asplenia or polysplenia due to defective left–right axis development, as well as decussation defects such as ACC, are considered as defects of the primary developmental field. Therefore, additional callosal agenesis in Ivemark syndrome may be a coherent and synchronic defect in the primary developmental field rather than a causally independent malformation. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献