No abstract

Interleukin-2 receptor (IL-2R) expression on bronchoalveolar lavage (BAL) cells was studied in patients with sarcoidosis using immune cytochemistry and cytometric analysis. A low percentage of alveolar lymphocytes (AL) was found positive for IL-2R, with 7% in patients with impaired lung function and 6% in patients with normal lung function (0.4% in control subjects). Expression of IL-2R on alveolar macrophages (AM) was considerably higher, with 25% in patients with lung function impairment compared with 14% in patients without lung function impairment (1.5% in control subjects). Serum-soluble IL-2R (ssIL-2R) was significantly elevated only in patients with impaired lung function (140.0 pM), but not in patients with normal lung function (52.2 pM; control subjects, 40.0 pM). These elevated levels of ssIL-2R positively correlated with the percentage of IL-2R positive AM (p < 0.001). Immunosuppressive treatment in three patients resulted in a decrease of IL-2R+ AM and in a decrease of ssIL-2R, whereas IL-2R+ AL were unaffected. The positive correlation and the concomitant decrease of IL-2R+ AM and ssIL-2R are consistent with the idea that in sarcoidosis with clinically apparent lung involvement, elevated levels of ssIL-2R may be derived from AM and may thus be a useful indicator of the degree of activation of these cells.

Measurements are made of isochronal annealing in aluminium, copper, silver, and gold, after irradiation a t 4.5 O K with various doses of fast neutrons. It is shown that the relative amount of recovery within annealing stage I is reduced, and annealing stage 111 is shifted to lower temperatures with increasing defect concentration. The first observation can be explained b y the higher probability for annihilation of close Frenkel-pairs, during the radiation-annealing process, compared with the probability for recombination of more distant Frenkel-pairs. The shift with concentration of annealing stage 111 and annealing stage IE for aluminium indicates the existence of freely-migrating defects. For aluminium the existence of two freely-moving interstitials is confirmed. I n addition it is shown that the observed annealing behaviour of all the metals considered can be explained by this twointerstitial model (previously proposed by SEEGER and SOSIN) taking into account the different defect arrangements produced by low-temperature electron and neutron irradiation. Isochrone Erholungskurven von Aluminium, Kupfer, Silber und Gold nach Reaktorstrahlung bei 4,5 "K zeigen, daR mit zunehmender Dichte der durch die Bestrahlung erzeugten Defekte die Hohe von Erholungsstufe I abnimmt UndErholungsstufe 111 sich zu tieferen Temperaturen verschiebt. Ersteres kann durch die gegeniiber weiter entfernten Frenkelpaaren erhohte Reaktionswahrscheinlichkeit von eng benachbarten Frenkelpaaren bei den wahrend der Bestrahlung ablaufenden athermischen Rekombinationsprozessen erklart werden. Die Verschiebung der Erholungsstufe 111 sowie der Stufe IE in Aluminium mit der Ausgangsdichte der Defekte zeigt, da13 in diesen Stufen frei bewegliche Zwischengitteratome mit Leerstellen rekombinieren. Durch AusschluB aller anderen Moglichkeiten wird fur Aluminium das von SEEGER und SOSIN bereits friiher geforderte Modell zweier frei beweglicher Zwischengitteratome bewiesen. Ferner wird gezeigt, wie dieses Modell auch das Erholungsverhalten der anderen Metalle gut erklart, wenn man nur die verschiedene raumliche Anordnung der Defekte nach Elektronen-und Neutronenbestrahlung berucksichtigt.Copper, silver, gold, and aluminium were irradiated at 4.5 O K up to various doses of fast neutrons in the low-temperature irradiation facility of the FRM [l].Subsequent to the irradiation the annealing behaviour of the electrical resistivity change was investigated. Because of difficulties connected w-ith the temperature control of the helium gas stream used to heat the samples, no exact isochronal annealing program could be performed. Thus it was not possible to achieve annealing periods longer than the time required to heat the samples to the desired temperature. Isochronal annealing curves found under these conditions are shown in Fig. 1 to 4. Ail these curves exhibit the structure well-known, for example, from the experiments of BLEWITT [2]. I n addition one can clearly recognize the influence of the initial defect concentration upon the subsequent recovery of the...

Large radiation annealing effects are observed for different metals during reactor irradiation at 4.5 °K. Saturation values for the resistivity changes are obtained by extrapolation from the linear decrease of the effective damage rate with defect concentration. These results agree well with those deduced from radiation annealing observed during irradiation with heavy charged particles. Various physical processes which are thought to contribute to the observed reduction of the accumulation rate of defects with irradiation time, are analysed.

Abslract-Aluminium impurities were injected into the plasma of the MT-IM Tokamak. Line radiation of diRcrent aluminium ions (from AI I t o AI VIII) were identified. Two velocities were found for the toroidal dispersal: one is of the order ofU.1 cm fisc' for a few cmlimetres in the vicinity of the injection. the other is highcr than I cm for the whole Tokamak.fo!!owing. The ifijc&d ions gain !heir toroidal yp!ficity throcgh Co~!omb co![isiofis