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Recombinant human alpha lymphotoxin (rLT) administered intravenously to Lewis rats induces peripheral neutrophilia and lymphopenia in a dose-response dependent fashion. A dose of 30,000 units of rLT induced a neutrophilia (1589 +/- 326 to 5554 +/- 1050 neutrophils/cu mm) and lymphopenia (10,368 +/- 992 to 4636 +/- 878 lymphocytes/cu mm) at 2 hours after injection that was highly significant (P less than 0.001 and P less than 0.001, respectively) in comparison with vehicle controls. The kinetics of the neutrophilia that peaked at 2 hours as well as of the lymphopenia were highly reminiscent of the neutrophilia and lymphopenia following intravenous administration of either recombinant human interleukin-1 (IL-1) alpha or beta to rats. The peripheral neutrophilia was accompanied by a significant depletion of bone marrow neutrophils (P less than 0.001), as is also known to occur after administration of IL-1. Systemic blood pressure was not affected by rLT, which suggested that the changes in circulating leukocyte subsets were not attributable to hemodynamic changes nor to the hemodynamic-change-related release of adrenal hormones. Adrenalectomy did not alter the rLT-induced neutrophilia or lymphopenia, which suggested that rLT does not mediate its hematologic effects on peripheral blood leukocytes via the release of adrenal hormones. Pretreatment of rats with dexamethasone, indomethacin, or aspirin also did not alter rLT-induced neutrophilia or lymphopenia, which suggested that rLT-induced hematologic effects were not mediated via arachidonic acid metabolites, in stark contrast to IL-1 induced neutrophilia, which is inhibited by both dexamethasone and indomethacin.  相似文献   
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SUMMARY Four specialised air mattresses had interface pressure measured under six body sites prone to pressure sores in 10 subjects, supine and sitting. The mattresses were the Clinirest (SSI) and FirstStep (KCI) continuous airflow mattress overlays, and Airwave (Pegasus) and Nimbus (Huntleigh) alternating pressure air mattresses. On the mattress overlays, average supine interface pressures were 2.33 kPa (scapula), 4.15 kPa (elbow), 1.94 kPa (sacrum) and 2.79 kPa (buttock), although they were higher at the occiput (7.97 kPa) and heel (11.7 kPa). The alternating pressure air mattresses had an average minimum interface pressure close to zero for three sites, rising to 4.28 kPa under the heel. Average maximum interface pressures were 8.61 kPa (occiput), 5.21 kPa (scapula), 4.90 (elbow), 4.85 kPa (sacrum), 4.61 kPa (buttock) and 13.2 kPa (heel). No accepted scientific method exists for comparing the two types of mattress. Our data suggest a clinical benefit at the occiput and heel (supine) in using an alternating pressure air mattress and a benefit in using a continuous airflow mattress overlay at other sites.  相似文献   
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T C Keys  M A Judson  C E Reed    S A Sahn 《Thorax》1994,49(5):525-526
A 27 year old HIV infected man presented with two days of haemoptysis. Flexible bronchoscopy revealed a large carinal mass partially obstructing the left and right main stem bronchi. Rigid bronchoscopy was required to make the diagnosis of large cell immunoblastic lymphoma.  相似文献   
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Sixteen cohorts of men aged 40–59 years at entry were examined with the measurement of some risk factors and then followed-up for mortality and causes of death for 25 years. These cohorts were located in the USA (1 cohort), Finland (2), the Netherlands (1), Italy (3), the former Yugoslavia (5), Greece (2), and Japan (2), and included a total of 12,763 subjects.Large differences in age-adjusted coronary heart disease (CHD) death rates were found, with extremes of 45 per 1000 in 25 years in Tanushimaru, Japan, to 288 per 1000 in 25 years in East Finland. In general, higher rates were found in the US and Northern European cohorts as compared to the Southern European and Japanese cohorts. However, during the last 10 years of follow-up large increases of CHD death rates were found in some Yugoslavian areas. Out of 5 measured entry characteristics treated as age-adjusted levels (serum cholesterol, systolic blood pressure, cigarette smoking, body mass index and physical activity at work), only serum cholesterol was significant in explaining cohort differences in CHD death rates.Over 50% of the variance in CHD death rates in 25 years was accounted for by the difference in mean serum cholesterol. This association tended to decline with increasing length of follow-up, but this was due to the great changes in mean serum cholesterol in the two Jugoslavian cohorts of Velika Krsna and Zrenjanin. When these two cohorts were excluded the association increased with time.Changes in mean serum cholesterol between year 0 and 10 helped in explaining differences in CHD death rates from year 10 onward.It can be concluded that this study suggests that mean serum cholesterol is the major risk factor in explaining cross-cultural differences in CHD.  相似文献   
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MacEwan  DW 《Radiology》1987,163(2):559-563
Eleven radiologists appointed by the major radiological societies participated for the past 5 years in the development of the Health Policy Agenda for the American People. The Agenda is an action plan to address a wide variety of serious problems in medicine. The first phase involved establishment of 159 principles, broad value statements that were the foundation of the project. Phase 2 involved the development of policy proposals on 38 urgent issues for action in medical science; education; health resources; delivery mechanisms; evaluation, assessment, and control; and payment for services. These proposals are summarized in this report. The activities and recommendations of representatives for the field of radiology are described. The Agenda has been released, and an implementation phase has begun. It will likely be of great importance to the practice of radiology over the next decade. Important issues can be addressed by acting with the coalitions that are being formed from among the more than 150 participating organizations.  相似文献   
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