The first search for the decay K^+ -> pi^+ pi^0 nu nubar has been performed with the E787 detector at BNL. Based on zero events observed in the kinematical search region defined by 90 MeV/c < ...P_{pi^+} < 188 MeV/c and 135 MeV < E_{pi^0} < 180 MeV, an upper limit B(K^+ -> pi^+ pi^0 nu nubar) < 4.3 x 10^{-5} at 90% confidence level is established.
An upper limit on the branching ratio for the decay K+ --> e+ nu mu+ mu- is set at 5.0 x 10^{-7} at 90% confidence level, consistent with predictions from chiral perturbation theory.
We have observed the rare decay K+ --> pi+ mu+ mu- and measured the branching ratio Gamma(K+ --> pi+ mu+ mu-)/Gamma(K+ --> all) = (5.0 +/- 0.4 (stat.) +/- 0.7 (sys.) +/- 0.6 (theor.)) x 10^{-8}. We ...compare this result with predictions from chiral perturbation theory and estimates based on the decay K+ --> pi+ e+ e-.
85Sr-scintimetry in femoral neck fracture Brümmer, R; Hansson, L I; Mortensson, W ...
Archives of orthopaedic and traumatic surgery,
1982, Letnik:
101, Številka:
1
Journal Article
Recenzirano
In 40 patients with fracture of the femoral neck 85Sr scintimetry was performed at the time of nailing and 4 months postoperatively. The fractures were radiographed repeatedly for 5 years; thirteen ...fractures healed without complications, 22 developed necrosis of the femoral head, and 5 pseudarthrosis. The early isotope measurement did not distinguish between normal and necrosis cases even with detailed analysis. The 4 months activities were high in osteonecrosis and low pseudarthrosis. The latter observation is interpreted as evidence that non-union of a femoral neck fracture is due to severe permanent vascular damage.
The first observation of the decay K^+ --> pi^+ gamma gamma is reported. A total of 31 events was observed with an estimated background of 5.1 +- 3.3 events in the pi+ momentum range from 100 MeV/c ...to 180 MeV/c. The corresponding partial branching ratio, B(K+ -> pi+ gamma gamma, 100 MeV/c < P_pi^+ < 180 MeV/c), is (6.0 +- 1.5 (stat) +- 0.7 (sys)) x 10^{-7}. No K^+ --> pi^+ gamma gamma decay was observed in the pi^+ momentum region greater than 215 MeV/c. The observed pi^+ momentum spectrum is compared with the predictions of chiral perturbation theory.
Natural killing (NK) by peripheral blood mononuclear cells (PBMC) against K562 cells was examined in 27 patients with Sjoegren's syndrome and 17 normal control. NK activity in the patients was ...significantly reduced compared with normal controls. Patients with secondary Sjoegren's had lower cytotoxicity compared with those who had primary Sjoegren's. The proportion of PBMC with characteristics of NK cells was not decreased in the patients. NK by normal PBMC was diminished both in the presence of sera from patients with reduced NK and when the effector cells were pretreated with the sera. Pretreatment of target K562 cells did not alter NK activity. Suppression of NK by sera from patients did not correlate with levels of immune complexes or with antilymphocyte antibodies. Some patients had adherent cells which inhibited NK function. The data suggest that multiple mechanisms are involved in the defective NK activity seen in patients with Sjoegren's syndrome. The reduction of NK activity in Sjoegren's syndrome may contribute to the increased incidence of lymphoid malignancy