The cosmic X-ray experiment aboard HEAO-1

The HEAO-1 A-2 experiment, designed to study the large scale structure of the galaxy and the universe at X-ray energies is described. The instrument consists of six gas proportional counters of three types nominally covering the energy ranges of 0.15-3 keV, 1.2-20 keV, and 2.5-60 keV. The two low energy detectors have about 400 sq cm open area each while the four others have about 800 sq cm each. Dual field of view collimators allow the unambiguous determination of instrument internal background and diffuse X-ray brightness. Instrument characteristics and early performance are discussed

Measurement of the Top Quark p T Distribution

We have measured the p(T) distribution of top quarks that are pair produced in p (p) over bar collisions at roots = 1.8 TeV using a sample of t (t) over bar decays in which we observe a single high-P-T charged lepton, a neutrino, and four or more jets. We use a likelihood technique that corrects for the experimental bias introduced due to event reconstruction and detector resolution effects. The observed distribution is consistent with the standard model prediction. We use these data to place limits on the production of high-p(T) top quarks suggested in some models of anomalous top quark pair production

Improvement in cholestasis associated with total parenteral nutrition after treatment with an antibody against tumour necrosis factor alpha

Background: Many patients receiving long-term total parenteral nutrition (TPN) develop liver disease; cholestasis is common and may be severe. Antitumour necrosis factor alpha (TNFalpha) antibodies have recently been used in order to treat Crohn's disease, but their effect on cholestasis in humans has not been previously described. Case report: A 45-year-old woman had complicated Crohn's disease with multiple fistulae and only 1 m of residual small bowel. She had been receiving TPN for 2.5 years when she developed cholestasis which worsened despite adjustments to her TPN regimen. Infliximab, an anti-TNFalpha antibody, was given with the aim of treating an enterocutaneous fistula, but it also produced a marked biochemical and histological improvement in the TPN-related cholestasis. Conclusions: Anti-TNFalpha antibodies appeared in this case to improve TPN-related cholestasis. This implies that TNFalpha may play an important role in the development of this condition