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981.
This paper has been described an automatised method for determination of central dynamic moments of inertia of body segments. The method has been established for measuring female subjects. The body is sectioned into 16 segments, which are modelled using geometric solids. Measuring has been performed on 120 female subjects. Dynamic moments of inertia have been determined for all three axes of local co-ordinate systems in segments' centres of mass. The results are statistically analysed and divided into five percentile groups. Method described in this work represents simple, quickly and reliable manner of dynamic anthropomeasures determination. 相似文献
982.
The spatial distribution, movement, and impact of the untreated wastewater outfall from McMurdo Station, Antarctica, were investigated under early austral summer conditions. The benthic environment was examined to determine the distribution of Clostridium perfringens in sediment cores and the intestinal contents of native invertebrates and fish along a transect of stations. These stations extended ca. 411 m south of the outfall. The findings revealed that the concentration of C. perfringens decreased with depth in the sediment and distance from the outfall. High percentages of tunicates and sea urchins were colonized with this bacterium along the transect. Coprostanol concentrations were also measured in sediment samples taken from each of the transect stations, and a similar trend was observed. These results are in agreement with the findings of previous studies performed with the water column and collectively provide evidence that the disposal of domestic wastes deserves special consideration in polar marine environments. 相似文献
983.
984.
MN Feinglos CR Thacker B Lobaugh DD DeAtkine DB McNeill JS English DL Bursey 《Canadian Metallurgical Quarterly》1998,39(3):193-199
OBJECTIVES: To identify ethical dilemmas experienced by occupational and physical therapists working in the UK National Health Service (NHS). To compare ethical contexts, themes and principles across the two groups. DESIGN: A structured questionnaire was circulated to the managers of occupational and physical therapy services in England and Wales. SUBJECTS: The questionnaires were given to 238 occupational and 249 physical therapists who conformed to set criteria. RESULTS: Ethical dilemmas experienced during the previous six months were reported by 118 occupational and 107 physical therapists. The two groups were similar in age, grade, and years of experience. Fifty of the occupational therapy dilemmas occurred in mental health settings but no equivalent setting emerged for physical therapy. Different ethical themes emerged between the two groups, with the most common in occupational therapy being difficult/dangerous behaviour in patients and unprofessional staff behaviour, and for physical therapists resource limitations and treatment effectiveness. No differences were found in the ethical principles used. CONCLUSION: The ethical dilemmas reported by the therapists were primarily concerned with health care ethics, rather than the more dramatic ethics reported in much of the biomedical ethics literature. Differences were found between the two professional groups when ethical contexts and themes were compared but not when ethical principles were compared. This suggests that educators and researchers need to be aware of work settings and the interdisciplinary nature of employment as well as ethical principles held by individual therapists. 相似文献
985.
986.
DD Lasic 《Canadian Metallurgical Quarterly》1998,16(7):307-321
Opinions of the usefulness of liposomes in various biotechnological applications range from unsubstantiated optimism to undeserved pessimism. This article reviews the background and development of liposomes, describes products that are commercially available and speculates optimistically about some future applications. The current deepening and widening of interest in liposomes in many scientific disciplines, and their application in medicine, immunology, diagnostics, cosmetics, ecology, cleansing and the food industry are promising novel breakthroughs and products. 相似文献
987.
PJ Ala RJ DeLoskey EE Huston PK Jadhav PY Lam CJ Eyermann CN Hodge MC Schadt FA Lewandowski PC Weber DD McCabe JL Duke CH Chang 《Canadian Metallurgical Quarterly》1998,273(20):12325-12331
As long as the threat of human immunodeficiency virus (HIV) protease drug resistance still exists, there will be a need for more potent antiretroviral agents. We have therefore determined the crystal structures of HIV-1 protease in complex with six cyclic urea inhibitors: XK216, XK263, DMP323, DMP450, XV638, and SD146, in an attempt to identify 1) the key interactions responsible for their high potency and 2) new interactions that might improve their therapeutic benefit. The structures reveal that the preorganized, C2 symmetric scaffolds of the inhibitors are anchored in the active site of the protease by six hydrogen bonds and that their P1 and P2 substituents participate in extensive van der Waals interactions and hydrogen bonds. Because all of our inhibitors possess benzyl groups at P1 and P1', their relative binding affinities are modulated by the extent of their P2 interactions, e.g. XK216, the least potent inhibitor (Ki (inhibition constant) = 4.70 nM), possesses the smallest P2 and the lowest number of P2-S2 interactions; whereas SD146, the most potent inhibitor (Ki = 0.02 nM), contains a benzimidazolylbenzamide at P2 and participates in fourteen hydrogen bonds and approximately 200 van der Waals interactions. This analysis identifies the strongest interactions between the protease and the inhibitors, suggests ways to improve potency by building into the S2 subsite, and reveals how conformational changes and unique features of the viral protease increase the binding affinity of HIV protease inhibitors. 相似文献
988.
Z Wang CM Lyles C Beyrer DD Celentano D Vlahov C Natpratan R Markham C Khamboonruang K Nelson XF Yu 《Canadian Metallurgical Quarterly》1998,178(5):1507-1511
The C2-V3 region of the human immunodeficiency virus (HIV)-1 env was determined from 15 northern Thailand seroconverters between 1993 and 1995. Similar sequences were also determined from 18 seroconverting injection drug users in Baltimore. All seroconverters from northern Thailand were infected with subtype E HIV-1 on the basis of env sequences. Intersubject viral DNA distances increased from 2.3% in asymptomatic HIV-1-infected subjects characterized between 1990 and 1992 to 7.8% in these more recent seroconverters from Thailand. On the other hand, sequences from 18 seroconverters from Baltimore had a mean intersubject distance of 13.2%. The genetic diversity within HIV-1 subtype E in seroconverters in Thailand has increased significantly but is still less than that observed in HIV-1 from seroconverters in the United States, where the epidemic of HIV-1 infection is more mature. These results suggest that continued monitoring of the molecular epidemiology of HIV-1 infection in Thailand will be important for HIV vaccine development and evaluation. 相似文献
989.
990.
Leg ulcers comprise a problem with various contributing factors requiring selective therapy adapted to the underlying cause. The majority can be classified as arterial (approx. 20%) or venous (approx. 80%) ulcers. Arterial ulcers as well as most mixed (arterial-venous) ulcers can be treated by arterial reconstruction and subsequent skin grafting, with additional ligation of perforator veins or (segmental) stripping of the saphenous vein. Leg ulcers due to chronic insufficiency of the deep venous system are most often the result of previous deep venous thrombosis followed by recanalization and development of a postthrombotic syndrome. Compression regimens remain standard therapy with emphasis on preventing ulcer formation. Ulcer healing can be achieved by compression therapy although recurrence rates are high. Surgery is not the treatment of first choice for leg ulcers, however, in selected cases surgical therapy is indicated. To prevent recurrence, continued consistent compression, keeping the patient well-informed and offering supportive guidance are imperative. 相似文献