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131.
The outdating of units of blood can be reduced by decreasing the amount of time they spend in an assigned or crossmatched status. This reduction can be achieved in a hospital by establishing a maximum surgical blood order schedule (MSBOS) which reduces the excessive number of units of blood crossmatched preoperatively for patients undergoing elective surgery. The various steps which occurred in the development of a MSBOS in a large general hospital are detailed and the projected reduction in the number of crossmatched units which can be achieved with the MSBOS is illustrated. illustrated. The projected number of units of blood transfused to patients during their hospitalization for 50 common primary surgical procedures in the United States during 1974 is presented as a basis for defining maximum blood orders for each procedure. 相似文献
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134.
Julia M. Friedman 《The Annals of Regional Science》1975,9(1):45-55
The Federal Water Pollution Control Act of 1972, P.L. 92-500, requires tertiary treatment of all effluent by 1983; Oregon State policy focuses on maintaining future effluent discharges at a level no greater than current levels. The Federal and State policies are combined in planning for the future management of the quality of the Willamette River. As a consequence, the Willamette will be clean-too clean- and the economic inefficiency inherent in the water quality control plan will cause misallocation of public resources. This misallocation could be avoided by incorporating economic principles, especially cost comparisons and the consideration of alternative procedures, into the water quality plan. 相似文献
135.
Zhao S Datta AR Ayers S Friedman S Walker RD White DG 《International journal of food microbiology》2003,84(1):87-92
A total of 187 Salmonella isolates representing 82 serotypes recovered from 4072 imported foods in the year 2000 by the U.S. Food and Drug Administration field laboratories were tested for their susceptibility to 17 antimicrobials of human and veterinary importance. Fifteen (8%) isolates were resistant to at least one antimicrobial, and five (2.7%) were resistant to three or more antimicrobials. Most of the isolates (n=9) exhibited resistance to tetracycline. Four isolates from catfish or tilapia from Taiwan or Thailand also demonstrated resistance to nalidixic acid. These nalidixic acid-resistant Salmonella isolates possessed a point mutation at the Ser83 or Asp87 position in DNA gryase, resulting in amino acid substitutions to phenylalanine, tyrosine, or asparagine. One Salmonella Derby isolated from frozen anchovies imported from Cambodia was resistant to six antimicrobials including ampicillin, amoxicillin/clavulanic acid, chloramphenicol, sulfamethoxazole, tetracycline, and trimethoprim/sulfamethoxazole. Of seven isolates displaying resistance to sulfonamides, only one S. Derby and one Salmonella Agona contained class 1 integrons that were further shown to possess the aadA and pse-1 genes conferring resistance to streptomycin and ampicillin, respectively. This study indicates that antimicrobial-resistant Salmonella are present in imported foods, primarily of seafood origin, and stresses the need for continued surveillance of foodborne zoonotic bacterial pathogens from imported foods entering the United States. 相似文献
136.
Using a Michelson white-light interferometer, we measure the group-delay dispersion and third-order dispersion coefficients, d2(phi)/d(omega)2 and d3(phi)/d(omega)3, of chromium-doped forsterite (Cr:Mg2SiO4) over wavelengths of 1050-1600 nm for light polarized along both the c and b crystal axes. In this interval, the second-order dispersion for the c axis ranges from 35 fs2/mm to -14 fs2/mm, and the third-order dispersion ranges from 36 fs3/mm to 142 fs3/mm. For the b axis the second-order dispersion ranges from 35 fs2/mm to -15 fs2/mm and the third-order from 73 fs3/mm to 185 fs3/mm. Our data are relevant for the development of optimized dispersion compensation tools for Cr:Mg2SiO4 femtosecond lasers. These measurements help to clarify previously published results and show some significant discrepancies that existed, especially in the third-order dispersion. Our results should furthermore be useful to build up an analytic expression for the index of refraction of chromium forsterite. 相似文献
137.
Hilary Alto Rangaraj M. Rangayyan Raman B. Paranjape J. E. Leo Desautels Heather Bryant 《电信纪事》2003,58(5-6):820-835
Computer-aided diagnosis (cad) systems are being developed to assist radiologists in the interpretation of ambiguous mammographic features corresponding to possible signs of early breast cancer. Databases of digital mammograms are needed for testing such systems; we present an overview of a few such databases. Most databases are limited to single-exam sets of two or four mammograms on which the diagnosis was made, some ground-truth information related to the position of diagnostically significant mammographic features, and the diagnosis. We propose the design of a comprehensive, indexed atlas of digital mammograms. The design of an appropriate indexing scheme facilitates the implementation of content-based retrieval techniques needed for efficient access to and retrieval of relevant cases from the atlas. We also propose the use of mobile software agents for facilitating remote consultation of the atlas. Mobile agents can move between data sources such as the atlas and hospital repositories, perform computational tasks at each site, and return only relevant data to the user. These features reduce the computational requirements of the local computer system, bandwidth requirements, and overall network traffic. Proposed applications of the atlas include research, remote consultation, teaching, evaluation ofcad systems, and self-evaluation by radiologists. 相似文献
138.
N-grams are generalized words consisting of N consecutive symbols, as they are used in a text. This paper determines the rank-frequency distribution for redundant N-grams. For entire texts this is known to be Zipf's law (i.e., an inverse power law). For N-grams, however, we show that the rank (r)-frequency distribution is
, where N is the inverse function of fN(x)=x lnN–1x. Here we assume that the rank-frequency distribution of the symbols follows Zipf's law with exponent . 相似文献
139.
Martin Leslie R.; Friedman Howard S.; Schwartz Joseph E. 《Canadian Metallurgical Quarterly》2007,26(4):428
Objective: This study addressed whether personality in childhood and personality in adulthood are independent predictors of mortality risk and the extent to which behavioral and other psychosocial factors can explain observed relationships between personality and mortality risk. Design: This was a prospective longitudinal cohort study of 1,253 male and female Californians over 7 decades (1930-2000). Proportional hazards regressions were the principal analyses. Main Outcome Measures: Mortality risk (in the form of relative hazards) was the primary outcome. Additional tests of mediators and moderators ascertained whether associations between personality and mortality risk remained significant when psychosocial and behavioral variables were statistically controlled. Results: The findings, including a new 14-year additional follow-up in old age, revealed that conscientiousness, measured independently in childhood and adulthood, predicted mortality risk across the full life span. The link from childhood remained robust when adult conscientiousness and certain behavioral variables were controlled. Psychosocial and behavioral variables partly explained the adult conscientiousness-longevity association. Conclusion: The findings demonstrate the utility and complexity of modern personality concepts in understanding health and point to conscientiousness as a key underexplored area for future biopsychosocial studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
140.
Responds to a commentary by R. Wallerstein (see record 2007-10890-011) on the present author's original article (see record 2006-05420-002) regarding the evolution of psychoanalytic theory. I do not believe that misunderstanding or misrepresentation has played a part in these differences. What I think has been at play for almost 20 years has been a difference in outlook on scientific and social issues, and in our interpretations of the historical course of events affecting psychoanalytic theory. These are reversing in recent years, which I welcome. No objective events have taken place to account for these changes, only subjective developments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献