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AM Lacy 《Canadian Metallurgical Quarterly》1998,10(3):279-86; quiz 288
Due to aesthetic and periodontal factors, patients often seek treatment to close diastemata. This condition may be eliminated by either direct or indirect techniques. Indirect techniques generally require multiple visits to facilitate the placement of laminate, crown, or bridge restorations, and involve significant financial expense. Direct techniques can be economical and successful, although they present unique challenges in the achievement of satisfactory proximal contacts and contours. This article describes three clinical techniques that may be employed to treat anterior and posterior diastemata in a single appointment. 相似文献
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The level of blood lipids and apolipoproteins in subjects being screened for abdominal aortic aneurysms have been investigated. As part of an ultrasound screening programme in a population of 65- to 75-year-olds, blood samples were collected from 1460 of 1504 subjects with a normal aorta (97.1%) and 69 of 70 patients with an abdominal aortic aneurysm > 29 mm (99%). Samples were also taken from 22 of 27 patients (81%) with an ectatic aorta (26-29 mm). Total cholesterol, HDL-cholesterol, LDL-cholesterol, Apo-AI and Apo-B levels were significantly higher in women than in men (P < 0.01). Levels of HDL-cholesterol and Apo-AI were significantly lower in patients with an abdominal aortic aneurysm than in normal subjects (P < 0.001). The mean(s.d.) body mass index was 25.1(3.9) in women and 25.5(3.2) in men with aneurysms and not significantly greater than that of normal subjects (25.2(3.61) and 25.2(3.38) respectively). 相似文献
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The role of clinical pharmacology in improving the prevention and treatment of malaria is reviewed. A series of general and specific issues is discussed, concentrating on risk-benefit and cost-effectiveness. The techniques of clinical pharmacokinetics play an important role in the optimal use of drugs and this is illustrated by studies on quinine and proguanil. In discussing amodiaquine toxicity, the role of the pharmacologist and the chemist in designing out drug toxicity lends hope for producing a new generation of antimalarial drugs. 相似文献
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cABL is a protooncogene, activated in a subset of human leukemias, whose protein product is a nonreceptor tyrosine kinase of unknown function. cABL has a complex structure that includes several domains and motifs found in proteins implicated in signal transduction pathways. An approach to elucidate cABL function is to identify proteins that interact directly with cABL and that may serve as regulators or effectors of its activity. To this end, a protein-interaction screen of a phage expression library was undertaken to identify proteins that interact with specific domains of cABL. An SH3-domain-containing protein has been identified that interacts with sequences in the cABL carboxyl terminus. The cDNA encoding ALP1 (amphiphysin-like protein 1) was isolated from a 16-day mouse embryo. ALP1 has high homology to BIN1, a recently cloned myc-interacting protein, and also shows significant homology to amphiphysin, a neuronal protein cloned from human and chicken. The amino terminus has homology to two yeast proteins, Rvs167 and Rvs161, which are involved in cell entry into stationary phase and cytoskeletal organization. ALP1 binds cABL in vitro and in vivo. Expression of ALP1 results in morphological transformation of NIH 3T3 fibroblasts in a cABL-dependent manner. The properties of ALP1 suggest that it may be involved in possible cytoskeletal functions of the cABL kinase. Additionally, these results provide further evidence for the importance of the cABL carboxyl terminus and its binding proteins in the regulation of cABL function. 相似文献
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AM Pollock 《Canadian Metallurgical Quarterly》1995,310(6994):1580-1584
The Association of Metropolitan Authorities has recently proposed that responsibility for the NHS should pass from health authorities to local authorities. One of the fiercest debates at the outset of the NHS was whether the hospitals should be run by local authorities. In the end the minister for health, Aneurin Bevan, decided against local democracy and in favour of a national health service. His arguments included the fact that equality of treatment could not be guaranteed if facilities varied with local finances and that even the largest authorities were not big enough to pool risks and expertise. All these arguments still apply today, and the recent changes in community care provide an insight into how a market model of local authority control might work. The changes have been accompanied by a shift from public to private sector provision and the introduction of charges for services that the NHS once provided free. As important, the willingness and ability of local authorities to raise extra revenue from local taxes and charges affect the service they can provide, so leading to inequalities of provision. Local authorities have yet to make the case that they can preserve the fundamental principles and benefits of the NHS, including its reliance on central taxation and unified funding formulas. 相似文献
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Comparison of protein adsorption isotherms and uptake rates in preparative cation-exchange materials
Adsorption isotherms and effective diffusivities of lysozyme in a set of six preparative cation-exchange stationary phases were determined from batch uptake data in a stirred vessel. Both a pore diffusion and a homogeneous diffusion model were used in estimating diffusivities, with the isotherms fitted to a non-Langmuirian analytical isotherm equation. The capacities inferred from the isotherms are found to be correlated with the surface area accessible to lysozyme, the effective surface concentrations obtained being in agreement with values measured by different methods in various non-chromatographic systems. The pore diffusivities show systematic trends with protein and salt concentration, and effects of pore size and connectivity are also evident. Some trends in the homogeneous diffusivities are quite different to those in the pore diffusivities, but these differences largely disappear when the homogeneous diffusivities are rescaled to account for adsorption equilibrium behavior. Additional information is required to elucidate further the mechanisms of coupled diffusion and adsorption in stationary phases. 相似文献