Organische Leiter

Only three decades ago it was thought inconceivable that organic compounds could transport electric charges like metals do. However, recently organic molecules exhibiting high conductivities have been synthesized. Some examples of organic conductors are presented together with the present status of this research which is both interesting to chemists and physicists. Some applications of organic conductors are discussed.     

Patients' attitudes following chorionic villus sampling

The attitudes of 190 patients who had undergone chorionic villus sampling (CVS) were assessed by means of a questionnaire. One hundred and fifty-two patients replied of whom 68 (45 per cent) were referred because of increased maternal age and in the other 84 cases the indications included previous chromosomal abnormalities, fetal sexing, DNA analysis, and biochemical analysis. One hundred and twenty-two patients had a transcervical procedure, 24 had a transabdominal, and six patients required both procedures. One hundred and forty-one patients (93 per cent) reported CVS to be a satisfactory procedure, and the same percentage thought earlier diagnosis was beneficial. Thirty-nine patients (81 per cent) reported a better experience with CVS than with a previous amniocentesis. A majority of patients (93 per cent) wished a CVS in a future pregnancy and 137 patients (97 per cent) would accept a risk of miscarriage from the procedure of twice that quoted for amniocentesis (1 per cent).     

Rapid prenatal diagnosis of Patau's syndrome in a fetus with an abdominal wall defect by 72 hour culture of cells from amniotic fluid

A woman in the 32nd week of pregnancy was referred for investigation because of fetal abnormalities, including an abdominal wall defect, detected by ultrasonography. In view of the increased risk of chromosome abnormality, amniocentesis was performed to enable informed decisions about the management of the pregnancy and delivery to be taken. Cells from the liquor were inoculated into standard lymphocyte culture medium and incubated for 72 h. Slides with a high mitotic index and good quality metaphases, comparable to those from a blood culture, were obtained after harvesting. Cytogenetic analysis showed the karyotype to be 46,XY,—14,+t(13ql4q), which is consistent with Patau's syndrome. This technique appears to be an option for rapid karyotyping in cases of abdominal wall defect, where a chromosomal abnormality is suspected.     

Der Strahlungshaushalt der terrestrischen Planeten Venus,Erde und Mars

The radiation budget of planets substantially determines their climates. For the terrestrial planets having their own imperceptible heat source compared to the solar radiation, the radiation budget supplies energy that can be transformed and used in their atmospheres and at their surfaces. The crucial role of the radiation budget for the Earth's climate is manifested in current international programs like the World Climate and Global Change Programs. The intercomparison and analysis of the radiation budget of the terrestrial planets, due to quite different atmospheric compositions and external conditions, provide a deeper insight into the relations of the different components of the radiation budget.