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The present work is motivated by a long standing discrepancy between the electron temperature measurements of Thomson scattering (TS) and electron cyclotron emission (ECE) diagnostics for plasmas with strong auxiliary heating observed at both JET and TFTR above 6–7 keV, where in some cases the ECE electron temperature measurements can be 15%–20% higher than the TS measurements. Recent analysis based on ECE results at JET has shown evidence of distortions to the Maxwellian electron velocity distribution and a correlation with the TS and ECE discrepancies has been suggested. In this paper, a technique to determine the presence of non-Maxwellian behavior using TS diagnostics is outlined. The difficulties and limitations of modern TS system designs to determine the electron velocity distribution are also discussed. It is demonstrated that small deviations such as those suggested by previous ECE analysis could be potentially detected, depending on the spectral layout of the TS polychromators. The spectral layout of the JET high resolution Thomson scattering system is such that it could be used to determine these deviations between 1 and 6 keV, and the results presented here indicate that no evidence of non-Maxwellian behavior is observed in this range. In this paper, a modification to the current polychromator design is proposed, allowing non-Maxwellian distortions to be detected up to at least 10 keV.

We report the identification of a localized current structure inside the JET plasma. It is a field-aligned closed helical ribbon, carrying current in the same direction as the background current profile (cocurrent), rotating toroidally with the ion velocity (corotating). It appears to be located at a flat spot in the plasma pressure profile, at the top of the pedestal. The structure appears spontaneously in low density, high rotation plasmas, and can last up to 1.4 s, a time comparable to a local resistive time. It considerably delays the appearance of the first edge localized mode.

Between march 1988 and march 1991, 350 amniocenteses were performed as a part of the prenatal diagnosis program at the Instituto Nacional de Perinatología. Cytogenetic diagnosis was obtained in 348 cases (99.4%). A total of ten abnormal fetal karyotypes (2.9%) were detected: Down's syndrome, (5) Edwards' syndrome, (2) Turner's syndrome, (1) Klinefelter's syndrome (1) and chromosomal instability. (1) In addition, one carrier of a Robertsonian translocation, two balanced carriers of reciprocal translocations and three cases of true mosaicism, were also detected. In the group of patients studied for indications other than risk of chromosomopathy, one female fetus affected by congenital adrenal hyperplasia, was observed. There were two miscarriages, resulting in a post-procedural fetal loss of 0.57%.

Experience with intraperitoneal blood transfusion, using ultrasonographic guide, in 24 patients with severe isoimmunization to Rh factor, is reported. A total of 57 procedures, were done from 24 weeks of gestation. In 66.6% two or more transfusions were done in the same product. There were 71% of alive newborns and in 29% of the cases it was not possible to improve perinatal survival. The analysis of these results were correlated with antecedents: presence of hydrops, gestational age at the time of resolving pregnancy, and main disease status. The usefulness of intraperitoneal transfusion, is commented upon, and new perspectives, as intravascular transfusion in cases with severe hydrops, are considered.

In this paper, the approach to the genesis of the acute hypertension of pregnancy, uses a conceptual and methodological perspective adjusted to its multifactorial nature; a set of questions with epidemiologic focus is proposed, in order to vinculate psychosocial factors with the biologic processes characteristic of this health problem.

Human chorionic gonadotropin beta subunit (beta-HCG) was measured in amniotic fluid and radioimmunoassay levels compared with those obtained in plasma from normal pregnant women. Amniotic beta-HCG exhibited a secretory pattern similar to that seen in the plasma compartment. Nonetheless amniotic beta-HCG had an elevation peak later than its plasma counterpart, with a progressive decrease that persisted throughout gestation without reaching a nadir as it occurred in plasma. Such a pattern of HCG production contained in the amnion is compatible with an HCG conformation released by the syncytiotrophoblast.

A clinical analysis of 37 cases of twin pregnancy complicated by eclampsia showed that: (1) the incidence of twins in the total 1,030 cases of eclampsia was three times the figure in the general population, (2) the maternal mortality was slightly higher and perinatal mortality slightly lower than in unselected eclamptic patients, (3) patients with postpartum eclampsia showed significant differences in comparison with antepartum and intrapartum cases, (4) perinatal and maternal mortality were lower in cases delivered by cesarean section, (5) perinatal mortality was significantly higher in male fetuses, and (6) five of the six maternal deaths occurred in cases of male twins. In addition, the data suggest the presence of a reciprocal negative influence between maternal eclampsia and male twins and that this type of eclampsia may be the best example of essential preeclampsia.