人腰背筋膜的动态响应

本研究对人胸腰段脊柱的粘弹特性作了观察，对两组４０～８５岁的人体胸腰椎标本作了单轴拉伸断裂试验。根据解剖学纤维方向（即尾内侧和尾外侧方向）来选择两组标本。以五种不同的应变速率来判断标本的生物力学特性。获得每组标本的最大断裂应力、应变和杨氏模量。结果表明，两种解剖方向之间各种生物力学参数均无显著差异。然而，实验发现最大断裂应力、应变和杨氏模量随应变速率增加而增加。应变速率大于３／秒，则断裂应变和杨氏模量保持不变，提示已达到上限。     

A host-cell-selected variant of influenza B virus with a single nucleotide substitution in HA affecting a potential glycosylation site was attentuated in virulence for volunteers

Summary An influenza B virus was passaged in man (virus A) and then in human embryo trachea (C) and into embryonated eggs (D) or directly into eggs (B). Virus A, B, and C had the same (cell-like) haemagglutinin phenotype on reaction with selected monoclonal antibodies while D had an egg-like phenotype. The viruses were administered at a dose of 1,000 TCD₅₀ (for MDCK cells) by intranasal inoculation to groups of 27 or 28 volunteers. Viruses A, B, and C all produced disease in six to eight volunteers, whereas D produced no illness and only four volunteers were infected. The viruses shed by the volunteers were indistinguishable from those with which they were inoculated. The haemagglutinin genes of the viruses were sequenced and changes were detected indicating amino acid substitutions at position 196–198 in the attenuated egg-grown virus D whereby a potential glycosylation site present in the other viruses was lost.     

Measuring management training. Two new instruments

Seeks to enhance the measurement of training; describes the development of psychometrically sound and practical measures to assess outcomes relating to in-service management training within a National Health Service District. Develops legitimate measurement tools and demonstrates the positive effects of two specific programmes in relation to behavioural change and participant satisfaction. Further work is required to establish how to monitor the effects of the action learning process in terms of cognitive development.     

Biochemical interactions between methotrexate and 1-β-d-arabinofuranosylcytosine in hematopoietic cells of children: a Pediatric Oncology Group study

Summary Children with acute lymphocytic leukemia (ALL) in remission were treated with overlapping sequential infusions of methotrexate (MTX) and 1--d-arabinofuranosylcytosine (araC) as part of continuation therapy. The doses and the sequence were chosen to mimic conditions that produced greater than additive antineoplastic activity with these two drugs in preclinical studies. To assess the potential for the drug combination to exhibit greater than additive effect in vivo, we investigated several biochemical parameters that had been associated with synergism in vitro. Because the patients were in remission, the intracellular parameters could only be measured in cytologically normal hematopoietic cells. We observed that (1) the mean plasma concentrations of MTX and araC were above those required to obtain a greater than additive cytotoxicity with the two drugs in tissue culture; (2) MTX did not have a significant antipurine effect in bone marrow mononuclear cells; (3) the mean intracellular concentration of deoxycytidine triphosphate (dCTP) was significantly lower after treatment with the drug combination than after therapy with araC alone; and (4) the ratio of araC triphosphate (araCTP) to dCTP was 2.6 times higher after treatment with the combination than after araC alone. These results indicate that it is possible to achieve in patients the biochemical conditions associated with the greater than additive antineoplastic activity of MTX and araC in vitro.Abbreviations ALL acute lymphocytic leukemia - araC 1--d-arabinofuranosyluracil - araCTP araC triphosphate - araU 1--d-arabinofuranosyluracil - dNTPs deoxyribonucleoside triphosphates - MTX methotrexate - TCA trichloroacetic acid Supported in part by grants from the National Cancer Institute, National Institutes of Health (CA-38 053; CA-33572, CA-32278, CA-38 859, CA-29 691, and CA-30 969). Preliminary reports on the biochemical data were published by E. M. N., A. M. T., and D. P. inProc Am Assoc Cancer Res 24: 133 (1983) and those on the clinical data, by R. A K., E. M. N., D. P. R. B. R., M. B. H., Y. R., and A. I. F. inProc Am Soc Clin Oncol 3: 201 (1984)     

Recognition and management of Kawasaki disease

Kawasaki disease is the leading cause of acquired heart disease in children in the developed world, with coronary artery aneurysms occurring in up to 25% of untreated cases. The mean annual incidence of Kawasaki disease across Canada is about 13 per 100,000 children less than 5 years of age, based on hospital discharge data from 1990 to 1995. The cause remains unknown, and the diagnosis is based on the same clinical criteria used to describe the disease over 30 years ago. However, nonspecific clinical features, evolving presentations and atypical or incomplete presentations make early diagnosis and timely treatment difficult. Delays in diagnosis and treatment, which occur more frequently in older children, are associated with an increased risk of coronary artery aneurysms. Hence, high diagnostic suspicion and prompt referral are required to reduce the rate of cardiac complications.     

Professional associations and managed care. How four provider groups are helping their members

Managed care is facilitating rapid change in the day-to-day practice of many addiction treatment and mental health professionals. It is only natural, therefore, that the associations representing the various disciplines in behavioral healthcare should seek to present short- and long-term plans, advice, and programs for their members. We have asked leaders from four prominent groups to present what their organizations are doing today to assist professionals in adapting to the new realities of the healthcare system. The comments below are by no means conclusive, and are representative of a few efforts and thoughts. It is our mission at Behavioral Healthcare Tomorrow to provide an independent platform for dialogue in the world of mental health and addiction treatment. It is our hope that the proposals and ideas published here stimulate even more planning amongst providers as managed care assertively enters public sector services.     

Mission impossible? The definition and functions of the medical director

Seeks to throw light on both strategic and managerial aspects of the post of medical director. The medical director is a key executive member of the Trust Board, yet the role remains ill-defined. The existing published guidance gives some indication of what medical directors should be doing but gives limited information about "best practice" or how to cope with the demands being made on them. A survey of medical directors in 1994 revealed the diversity of the tasks that they can be called on to perform, often with inadequate managerial and secretarial support. The survey also indicated that problems have occurred as a result of the heavy workload and unexpected multiple facets of the role. Concludes that, to make the job somewhat easier, there should be a clear core job specification which is tailored to suit the individual circumstances. This should be combined with generous support and training, together with a suitable reward package.