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951.
Narrowband as well as wideband measurements have been performed in various indoor and outdoor environments in order to enable the development of reliable prediction models for 60 GHz radio channels. In addition, results of deterministic modelling on the basis of geometric ray-tracing have been compared with measurement results, showing that simple ray-tracing can be used to estimate both the narrowband and wideband characteristics of a 60 GHz radio channel. This paper reviews the measurement and modelling activities performed by various research institutes 相似文献
952.
Environmental data and information are two quite important instruments, which, together with other technical, financial and legal tools, will allow an adequate policy formulation and will make the assessment of its implementation possible. Information is not only a requirement for policy making or strategic planning but a tool of vital importance at the other two levels of the decision-making process: managerial and operational. In any case, to be useful, information must be relevant to the end to be achieved, complete and easily understood. If there is a need for data interchange, then it must be comparable and easily available. To obtain better environment and, at the same time, better and comparable data on this environment, the European Union issued a number of legal instruments (directives and council and commission decisions). After some generic considerations on information requirements, this paper presents a brief review of the water resources information policy in five European countries. The European information policy is also addressed, a special mention being made to the European Environmental Agency. 相似文献
953.
YJ Kim KE Pollok Z Zhou A Shaw JB Bohlen M Fraser BS Kwon 《Canadian Metallurgical Quarterly》1993,151(3):1255-1262
4-1BB is a 30-kDa inducible T cell Ag, and is expressed predominantly as a 55-kDa dimer on both CD4+ and CD8+ T lymphocytes. The cytoplasmic tail of 4-1BB contains the sequence Cys-Arg-Cys-Pro, which is similar to the sequence Cys-X-Cys-Pro, which mediates the binding of the CD4 and CD8 molecules to the protein tyrosine kinase p56lck. An anti-4-1BB mAb, 53A2, was used to determine whether 4-1BB may associate with p56lck. The 53A2 mAb specifically recognized 4-1BB on a CD8+ T cell line, CTLL-2, and coimmunoprecipitated a 56-kDa protein along with 4-1BB. Peptide mapping indicated that the 56-kDa phosphoprotein was identical to p56lck. The coimmunoprecipitation of p56lck with 4-1BB also occurred in nonlymphoid cells such as insect (Sf-21) and HeLa cells when the two recombinant proteins were coexpressed. Analysis of mutant p56lck recombinant proteins showed that two cysteine residues critical for p56lck-CD4 (or -CD8) complex formation are also required for the p56lck-4-1BB interaction. These studies establish that 4-1BB physically associates with p56lck. 相似文献
954.
CW Bradberry JB Nobiletti JD Elsworth B Murphy P Jatlow RH Roth 《Canadian Metallurgical Quarterly》1993,60(4):1429-1435
Cocaethylene is a pharmacologically active metabolite resulting from concurrent cocaine and ethanol consumption. The effects of cocaine and cocaethylene on extracellular levels of dopamine in the nucleus accumbens, and serotonin in the striatum were characterized in vivo in the anesthetized rat. Both intravenous (3 mumol/kg) and intraperitoneal (44 mumol/kg) routes of administration were used. In addition to monitoring neurotransmitter levels, microdialysate levels of cocaine and cocaethylene were determined at 4-min intervals after intravenous administration, and at 20-min intervals after intraperitoneal administration. Extracellular levels of dopamine in the nucleus accumbens were increased to approximately 400% of preinjection value by both cocaine and cocaethylene when administered intravenously. Cocaine caused a significant increase of striatal serotonin to 200% preinjection value, whereas cocaethylene had no effect. Brain levels of cocaine and cocaethylene after intravenous administration did not differ. After intraperitoneal administration, extracellular levels of dopamine in the nucleus accumbens were increased to 400% of preinjection levels by cocaine, but were only increased to 200% of preinjection levels by cocaethylene, the difference being statistically significant. Serotonin levels were increased to 360% of preinjection levels by cocaine, but only to 175% of preinjection value by cocaethylene. Levels of cocaine attained in brain were significantly higher than those for cocaethylene, suggesting pharmacokinetic differences with the intraperitoneal route. These results confirm in vivo that cocaethylene is more selective in its actions than cocaine with respect to dopamine and serotonin uptake. In addition, route-dependent differences in attainment of brain drug levels have been observed that may impact on interpretations of the relative potency of the reinforcement value of these compounds. 相似文献
955.
CB McCoy LR Metsch JB Page DC McBride ST Comerford 《Canadian Metallurgical Quarterly》1997,18(1):35-60
Miami is one of the major centers of illegal drug activity and has a significant proportion of AIDS cases among injection drug users (IDUs). Since Needle Exchange Programs (NEP) are illegal and therefore do not exist in the state of Florida, other strategies must play a large role in reducing the transmission of HIV among IDUs. In order to effectively communicate with IDUs about needle safety, it is necessary to understand the practices and culture of IDUs, including where and how the needle/syringes are obtained and used. Data from recent studies conducted in Miami and other local sites indicate that IDUs inject frequently, averaging more than 1,000 per year, per person. While the vast majority of IDUs feel it is very important to clean needles and to use a needle only one time, these sentiments are not always practiced. Furthermore, data indicate that the context where shooting takes place must be considered in the planning of HIV risk reduction interventions. These findings suggest the importance of understanding patterns of drug use, attitudes toward intervention, and the cultural context where risky behaviors occur. Although Needle Exchange Programs are illegal in Florida, intervention programs must still stress the importance of using only new needles, but since new needles cannot always be obtained, IDUs should be taught and motivated not to use contaminated drug paraphernalia. 相似文献
956.
957.
JB Holds JR Patrinely PL Zimmerman RL Anderson 《Canadian Metallurgical Quarterly》1993,100(10):1475-1482
BACKGROUND: A high-pressure stream from mechanical equipment may inject gas or liquids deep into the orbit with few initial clinical signs. Aggressive surgical debridement as used in the extremities for the treatment of injection injuries is not possible in the orbit. METHODS: Four patients with orbital injection injuries from farm or industrial equipment are presented. Previously reported cases of high-pressure injection injury are reviewed. RESULTS: Two patients suffered localized anterior orbital inflammation partially responsive to steroidal and nonsteroidal anti-inflammatory agents. Late debridement was required in one patient for a persistent lipogranuloma. Two patients suffered more dramatic and diffuse injections of hydrocarbon mixtures, requiring emergent early surgical debridement and decompression for compressive orbital signs. All patients attained an adequate functional outcome, with one patient's vision limited by a coexisting ocular injury. CONCLUSIONS: High-pressure orbital injection injuries manifest a spectrum of signs ranging from acute inflammation with tissue necrosis and compressive visual loss to late chronic inflammation with a pseudotumor-like course. The authors recommend the initial treatment of orbital injection injuries with systemic antibiotics followed by prompt neuroradiologic imaging. Systemic corticosteroids should be added for confirmed injection injuries with surgical debridement of discrete masses and orbital decompression when indicated. Continued therapy with anti-inflammatory medication may be required to suppress chronic inflammation with selective late surgical debridement of lipogranulomas. 相似文献
958.
959.
960.
A 66-year-old woman with longstanding psoriasis involving the skin presented with asymmetrical polyarthritis. Methotrexate (MTX) was given initially intramuscularly and orally. Intramuscular MTX was discontinued, and a few months after she had been taking only oral MTX she developed nodules, first in surgical incisions, and subsequently in her buttocks, thighs, legs, and arms. Reduction of the dose of oral MTX was followed by gradual diminution in size of the nodules and then total disappearance. 相似文献