金属结合剂金刚石工具在石材加工过程中的磨损(上)

讨论了金属结合剂金刚石工具在石材加工过程中的磨损机理和影响因素,并介绍了研究过程中采用的测量金刚石工具的磨损状况的两种方法.     

Wirkstofffreigabe aus Externa

Drug Release from Topicals Release rates of two topical corticosteroids and an antimicrobial substance were measured in a diffusion cell where the formulations and acceptor phases were separated by a thin porous polycarbonate film which, however, did not influence the kinetics of drug transport. Aqueous phosphate buffer (pH 6), n-octanol and isopropyl palmitate were selected as acceptor phases to represent both the hydrophilic and lipophilic substances found in the skin. Supported by microbiological agar diffusion tests it could be shown how drug release was influenced by drug solubility, its activity in solution and by its interactions with other components by e. g. adsorption, solubilization or inclusion in surfactant micelles. It is therefore suggested to determine the release rate from topicals independent of absorption into skin.     

Microbiological oxidation of 2-methylbutanol of differing enantiomeric ratios by Gluconobacter species

 2-Methylbutanoic acid, an aroma compound of high economic interest, was synthesised using Gluconobacter species for bioconversion. The main focus was on enantioselective effects during metabolism. A preference for the (S)-enantiomer was observed when the microorganisms were fed with 2-methylbutanol of known enantiomeric ratios. Received: 15 December 1997     

金属结合剂金刚石工具在石材加工过程中的磨损(下)

讨论了金属结合剂金刚石工具在石材加工过程中的磨损机理和影响因素，并介绍了研究过程中采用的测量金刚石工具的磨损状况的两种方法。     

The economic cost of musculoskeletal disorders in Canada

OBJECTIVE: This study estimated the total cost of musculoskeletal disorders for Canadians in 1994 and assessed the sensitivity of these cost estimates to variations in the definition of musculoskeletal disorders. METHODS: Disease-related costs, from a societal perspective, were measured using a prevalence-based analysis. First, direct treatment costs, including expenditures on hospitals and other institutions, physicians and other health professionals, drugs, research, and other items were assessed. Second, indirect costs associated with lost (or foregone) productivity due to disability and premature mortality were evaluated using the human capital approach. RESULTS: The total cost of musculoskeletal disorders in Canada was $25.6 billion (in 1994 Canadian dollars, $1.00 CDN approximately $0.75 US) or 3.4% of the gross domestic product. Direct and indirect costs were estimated at $7.5 billion and $18.1 billion, respectively. Lower and upper bound estimates of the total cost of musculoskeletal disorders, derived from the sensitivity analysis, were $19.9 billion and $30.8 billion, respectively. Wide variations were reported in the total cost of various musculoskeletal disorder subcategories, with the highest costs reported for injuries ($10.7 billion), back and spine disorders ($8.1 billion), and arthritis and rheumatism ($5.9 billion). CONCLUSIONS: The economic cost of musculoskeletal disorders was substantial and was sensitive to the definition of musculoskeletal disorders and other underlying assumptions. The hallmark of this study was the variation between subcategories in their cost, pattern of health resource use, and sequelae. The cost estimates may provide guidance in setting priorities for research and prevention activities.