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Egyptian Blue, a multicomponent synthetic blue pigment has been recorded in ancient Egypt since the Fourth Dynasty of the Old Kingdom (2600–2480 B.C.). The pigment consisting of cuprorivaite (CaCuSi4O10) with variable amounts of wollastonite (CaSiO3), Cu-rich glass and cuprite (Cu3O) or tenorite (CuO) was prepared by melting the copper-rich ingredient with lime and desert sand. Low melting temperatures (below 742 °C) were achieved by addition of flux-like plant ashes. The high quality of the pigments collected from monuments of the Fifth Dynasty (2480–2320 B.C.) may indicate that the first manufacture was in early dynastic or perhaps predynastic eras. During the reign of Thutmosis III (18th Dynasty, 1490–1436 B.C.) probably bronze filings were first applied as starting material, thus indicating a technological innovation. This new method was employed till the Roman times. 相似文献
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Prenatal real-time ultrasonographic diagnosis of microphthalmia is presented. Diagnosis was made at 18 weeks' gestation in a fetus of a patient with a previous infant affected with the syndrome of cryptophthalmia with absence of septum nasi and ambiguous genitalia (Fraser syndrome). Recognition of microphthalmia as a part of Fraser syndrome and the easy visualization of fetal facial bones and orbits in the second trimester made the diagnosis possible. 相似文献
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Hydrops fetalis was diagnosed at 22 weeks. An ultrasound examination demonstrated cardiomegaly and a fetal blood specimen obtained by cordocentesis revealed thrombocytopenia, anaemia, and neutropenia. Fetal paracentesis yielded straw-coloured fluid with electrolytes indicative of a transudate. Non-enveloped icosahedral viral particles approximately 23 mm in diameter were visualized in the ascitic fluid by electron microscopy. Immune electron microscopy confirmed human parvovirus B19. Direct fetal digitalization led to a reduction in umbilical artery resistance, a decline in the abdominal circumference from 20·3 to 17·8 cm, and resolution of the ascites within 72 h. Despite this dramatic response to therapy, fetal death occurred on day 5 of treatment. The initial maternal serum was positive for anti-B19 IgM and IgG antibodies. Electron microscopy of fetal cardiac tissue obtained post-mortem revealed intranuclear viral particles typical of B19, confirming the antenatal diagnosis of myocarditis. This case demonstrates that direct viral identification is applicable to prenatal diagnosis. To our knowledge, this is the first reported case of the antenatal diagnosis and palliative treatment of fetal viral infection. 相似文献
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Dr Alan E. Donnenfeld Larry R. Glazerman Denise M. Cutillo Ronald J. Librizzi Stuart Weiner 《黑龙江环境通报》1989,9(5):301-308
Selective termination by intracardiac potassium chloride injection was performed in twins discordant for hydrocephaly at 20 weeks' gestation. Because of the potential for vascular anastomoses to exist between the twins, fetal angiography was performed prior to the selective termination procedure. Determination of vascular connections between the fetuses was hindered by fetal bradycardia following intracardiac administration of contrast material. Selective termination was performed without difficulty using intracardiac potassium chloride (KCl) to produce asystole in the twin with hydrocephaly. The unaffected fetus appeared active and had a normal heart rate during and immediately after the procedure. However, both twins were found to have died the following day. Pathologic examination documented several vascular anastomoses between the monochorionic, diamniotic fetuses. A likely cause of death was exsanguination of the normal twin into the abnormal one. This case illustrates the difficulties encountered in selective termination of monozygotic twins and, to our knowledge, represents the first reported use of intrauterine fetal angiography. 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