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This paper reports on successful prenatal diagnosis of X-linked anhidrotic ectodermal dysplasia (AED) by means of light and electron microscopy on fetal skin biopsies obtained under fetoscopy. In the present family two brothers of the proband were severely affected with the full symptomatology of AED, the pregnant female and her mother revealed minor symptoms with patches of skin lacking vellus hair. Control of lesional skin of the affected family members by electron microscopy revealed no ultrastructural abnormalities. However, all biopsies lacked skin appendages including hair follicles, sebaceous glands, and sweat glands. The lack of pilosebaceous follicles can be used as a diagnostic criterion since these structures are fully developed in normal fetuses of 20 weeks whereas the development of sweat glands does not start before week 20 to 24 of fetal life. Skin biopsies were taken from various regions of the fetus at risk via fetoscopy in week 20 and processed for light and electron microscopy. All samples revealed complete absence of all skin appendages in contrast to a total of 61 non-AED fetuses. Thus positive prenatal diagnosis of AED was made and the pregnancy was terminated. Control investigations after abortion confirmed the diagnosis. 相似文献
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Gerhard Rheinheimer 《Die Naturwissenschaften》1998,85(7):318-329
3 , NOx, PO4) caused eutrophication and consequent oxygen depletion in coastal bottom waters as well as in the depths of the open sea.
In the anoxic sediments, hydrogen sulfide can be produced by protein-decomposing and sulfate-reducing bacteria. The bottom
fauna will be destroyed and only H2S tolerant microorganisms can survive.
Originating from cellulose manufacturing and from paper mills, large amounts of poisonous chlorinated compounds contaminated
the coastal waters of Sweden and Finland until the 1980s. Most of this material is still present in sediments of the central
Baltic Sea and can be resuspended by near bottom currents.
To reduce pollution and improve the situation in the Baltic Sea, the surrounding countries organized the Helsinki Convention,
which came into force on 3.5.1980. The Helsinki Commission (HELCOM) founded in 1974 acts as coordinator and is responsible
for the enforcement of the Baltic monitoring program and international research projects. The activities of HELCOM have led
to the reduction of dangerous pollutants which in turn has caused the regeneration of flora and fauna in some areas. Further
improvements can be expected. 相似文献
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