Improved geometry of double-sided polished parallel wafers prepared for direct wafer bonding.

Optical technological applications have upgraded polishing, including flat-surface polishing, to an extremely high level of geometrical precision. We deal with the application of this type of precision technology for the preparation of, e.g., silicon or fused-silica wafers that are thin compared to their diameter. To this end a standard optical polishing process using a double-sided polishing machine was modified by giving the polishing pad holder an adaptable curvature. By carefully choosing the process conditions 10-cm-diameter silicon and fused-silica wafers (500-µm thickness) were obtained with a very small deviation from parallelism in the 0.01-µm range. The level of smoothness, surface and subsurface damage, was identical with that required for integrated-circuit processing.

[Intravenously-administered immunoglobulins as first-choice agent in juvenile dermatomyositis]. / Intraveneus toegediend immunoglobuline als middel van eerste keuze bij juveniele dermatomyositis.

Dermatomyositis is an acquired disease characterised by symmetric predominantly proximal muscle weakness of the arms and legs, and misery. It may be associated with myalgia and there is often a characteristic rash. The mainstay of therapy is corticosteroids. Recently efficacy of intravenous immunoglobulin (IVIg) in chronic refractory dermatomyositis was reported. Because corticosteroids can cause serious side effects, we treated a seven-year-old girl suffering from dermatomyositis with IVIg as initial therapy. After two courses of IVIg infusions at a dose of 0.4 g/kg/day for five consecutive days, the patient made a rapid and complete recovery. This case shows that IVIg may be effective as initial therapy in patients with dermatomyositis. Whether IVIg is really a better treatment than corticosteroids should be investigated in a randomised study.

Measles in Tanzania: antibody response in children after vaccination and antibody state of mothers and newborns.

The antibody response to attenuated live measles vaccines was studied in two groups of 29 (A) and 53 (B) African children. In group A 22 sera and in group B 34 sera showed no pre-immunization haemagglutination inhibition (HI) titres. Vaccination resulted in seroconversion in 64 and 85% of groups A and B, respectively. The difference in antibody response between the two groups could be traced to children in the age group seven to eight months, where seroconversion was absent in 67% of group A children and in 0% of group B children. Antibody levels were studied in 234 mothers and their newborns. In 131 serum pairs the antibody levels of mother and child were similar. 78 (33%) of mothers showed a higher titre and 25 (11%) a lower titre than their babies. All newborns except one and all mothers except one possessed antibody titres above 10. Children in the age groups seven to eight months and nine to ten months showed antibody in 12 and 7%, respectively. Over 90% of these children had not been infected in the first ten months of life.