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61.
Studied Minnesota Multiphasic Personality Inventory (MMPI) profiles of 362 patients with acute and chronic low back pain (LBP) for replicable homogeneous subgroups using 3 cluster-analysis procedures. Two normal and 3 clinically elevated profile subgroups were identified. The 2 normal subgroups were characterized by relatively normal musculoskeletal condition and were least disabled but differed from each other in duration of pain, presence of physical abnormalities, and daily functioning. The most pathologic profile subgroup consisted largely of acute-pain patients whose musculoskeletal condition and daily functioning were similar to those of the normal subgroups. Patients in the 3 abnormal MMPI subgroups were exposed to more LBP physical-risk factors in the workplace. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Submicrometer powders of complex oxides were prepared via resin intermediates based on a starch type of organic precursor. A commercially available water-soluble starch derivative was (for the first time) used as the organic base for solution synthesis of ceramic powders. Calcination of the charred, fluffy, amorphous resins at a temperature below 600°C for 4 h yielded perovskite powders of Sr-doped LaMnO3 and Sr-doped La(Fe,Co)O3. Sr-doped LaCrO3 needed to be calcined above 750°C to ensure phase purity and to remove organic residue. Due to the low cost of starch derivatives, the process has the potential of being more economical than the commonly used Pechini's type process, which utilizes citric acid and ethylene glycol.  相似文献   
63.
64.
Guest Editorial     
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65.
Summary Polymeric antioxidants prepared from 2,6-di-tertiary-butyl-4-vinyl (4-lsopropenyl)phenol and butadiene or isoprene, and their hydrogenated products (6-8 mol % of phenolic AO in the polymer) were tested by oxygen uptake studies for their effectiveness as antioxidants for polyolefins and polydienes. The polymeric antioxidants seem to be slightly less effective in short-term protection against oxidation at 150° C as compared to low molecular weight antioxidants, but more effective in long-term protection of the polymer samples at a level of 0.1 weight percent.Part 43: P. Grosso, O. Vogl: J. Macromol. Sci. Chem., in pressNow Chemical Company, Midland, MI 48674, USATo whom all correspondence should be addressed: Herman F. Mark Professor of Polymer Science, Polytechnic Institute of New York, Brooklyn, NY 11201, USA  相似文献   
66.
The automation of the design of electronics has advanced greatly since the middle 1970s. The state of this development is such that additional considerations are now being incorporated into the automation process. One of the essential elements of a successful electronics design is reaching the reliability and maintainability (R&M) potential that should be achieved in any design effort. The automation of portions of the design process to address R&M must be based upon design rules that are basic to producing a reliable and maintainable system. This paper discusses a framework for considering these R&M design rules and points the developers of computer-aided engineering systems in the direction that is necessary if electronics designs are to realize their potential.  相似文献   
67.
Four sites in the Detroit River/Lake Erie western basin were evaluated for their toxicity. The evaluation was based on 1) bulk chemical characterization of the sediments, 2) chemical composition of the sediment elutriates, and 3) toxicity of the elutriates to ultraplankton and microplankton/net plankton. A sequence of decreasing contamination was determined from the chemical composition of the elutriates based on the elutriation release of metals such as Zn, Mn, Cd, Ni, and Co. Bioassessment of elutriate toxicity was determined by carbon-14 Algal Fractionation Bioassays (AFB's) which were conducted with various dilutions of standard and Chelex-100 treated elutriates. Site A (near Windsor, Ontario) and Site D (western Lake Erie) were found to be toxic to ultraplankton. The observed toxicity was attributed to the bioavailability and synergistic impact of elutriated metals on ultraplankton production. A direct relationship between the water soluble metal fraction and toxicity was observed. These results confirmed that sediment toxicity should not be evaluated solely on bulk chemical composition of the sediments. The AFB's have been proven useful in the bioassessment of sediments due to their rapidity/sensitivity and hence could be routinely used for the screening and early detection of contaminants affecting fast growing organisms which form the basis of the aquatic food chain.  相似文献   
68.
Buchbesprechung     
Ohne Zusammenfassung  相似文献   
69.
The possible flow measurement error due to heating or cooling of exhaust gases in the Single‐Burning‐Item (SBI) test is estimated from numerical experiments. It is illustrated that there is no one‐to‐one correspondence between the velocity profile shape and the instantaneous Reynolds number, due to the time‐dependent temperature and density profile evolution in the exhaust gas pipe. A non‐ambiguous relation is found between the velocity profile shape and an ‘effective’ Reynolds number, based on the turbulent viscosity. Maximum variations of the velocity correction factors, relating the mean velocity to the velocity on the pipe axis, are found to be in the order of 2% for limiting circumstances for the SBI test. The primary effect is caused by instantaneous Reynolds number variations. The effect of heating or cooling of the flow by the hot or cold pipe is noticeable, too. The statements are proved to be valid independent of the computational grid, the turbulence model and the time steps taken to obtain the numerical solutions. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
70.
Thrombocytopenia is a major cause of morbidity following intensive chemotherapy for acute leukemia. Over recent years, there has been an increasing use of platelet transfusions which, although generally efficacious to prevent severe hemorrhage, have associated risks of transmitting blood-borne disease and of alloimmunization. Therefore, there is a clinical requirement for a drug that will reliably alleviate the thrombocytopenia associated with leukemia therapy. The c-mpl ligand thrombopoietin is the most interesting factor for the treatment of thrombocytopenia because of its lineage specificity. Phase I and II studies confirm its biological efficacy to induce rise in platelet count in patients with solid tumors and acute leukemia. Several other pleiotropic hematopoietic growth factors are also currently in clinical trials. These include interleukin-6, interleukin-3, interleukin-11, PIXY321 and stem cell factor. The effects of these cytokines appear to be modest at most and, with the exception of interleukin-11, their side effects are likely to limit their clinical application. Combinations of factors may prove more efficacious approaches to enhance platelet recovery.  相似文献   
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