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991.
992.
During a 22-year period, 13 patients with hematologic diseases developed bacteremia caused by the Bacteroides fragilis group, with a frequency which remained almost unchanged. Nine patients (69%) had polymicrobial infections. Acute leukemia was the most common underlying disease. The lower intestinal tract (necrotizing enterocolitis and anorectal abscesses) was the most common source of infection. Prior antibiotic therapy was the most frequent host condition before bacteremia, followed by cancer chemotherapy, neutropenia, thrombocytopenia and hypoproteinemia. Septic shock occurred only in seven patients with polymicrobial infections. Six patients, including five with shock, died within a week of onset, while the other seven survived for at least three weeks. Despite its clinical similarity to aerobic gram-negative infection, bacteremia due to the B. fragilis group may well, therefore, be suspected particularly when neutropenic patients who present with lower intestinal symptomatology develop a persistent fever unresponsive to the initial empiric antibiotic therapy.  相似文献   
993.
The composition, thickness, thermodynamic activities of components, Gibbs energy and excess energy of formation of the surface layer on binary melts of iron, cobalt and nickel-based alloys with different interatomic interactions were evaluated with the aid of data from the literature and the authors measurements of the concentration dependence of the surface tension and molar volume.  相似文献   
994.
A new gram-positive, nonmotile coccus is described. Strains IFO 12422T (T = type strain) and IFO 15385 in the Institute for Fermentation, Osaka, culture collection, which were isolated from soil and water, respectively, have the following chemotaxonomic characteristics: menaquinone MK-9(H4); G + C content of DNA of 67 mol%; and LL-diaminopimelic acid, alanine, glycine, and glutamic acid in a molar ratio of ca. 1:2:1:1 (type A3 gamma). Mycolic acids are not present. The taxonomic characteristics of these organisms are different from those of previously described gram-positive, high-G + C-content cocci. The partial 16S rRNA sequence indicated that IFO 12422T represents a distinct line of descent among gram-positive bacteria with a high G + C content. The name Luteococcus japonicus gen. nov., sp. nov. is proposed. The type strain is strain IFO 12422.  相似文献   
995.
In this article the direct boundary element formulations of stretching and bending plate problems are combined together to solve thin walled structures and other similar frames. The final system is obtained by assuming each individual plane structural element as a subregion. After the necessary transforms of these equations they can be combined together taking into account the displacement compatibility and equilibrium conditions.  相似文献   
996.
Base alumina ceramics with dispersoids (BAC) are a new class of ceramics with improved mechanical properties as compared to pure alumina. They are obtained by dispersion of powder within an alumina matrix. Of the three new ceramics studied here, A20Z possesses the best mechanical properties as well as tribological properties superior to those of pure alumina whether it is used in ceramic-ceramic or ceramic-polyethylene combination.Mechanical behaviour and tissue response afterin vivo implantation were studied. Small four-point flexion bars obtained by pressureless sintering were implanted subcutaneously in the rat. The mechanical properties were unmodified even after one year from implantation.The tissue response was studied up to one year on cylinders implanted in the paravertebral muscles of Wistar rats, and was evaluated by qualitative examination of the encapsulating membrane and measurement of its thickness in relation to pure alumina. The tissue responses were comparable for both alumina and the three tested ceramics.  相似文献   
997.
998.
999.
A beam of fully polarized cold neutrons was transported through a zero magnetic field region of 70 m length without loss of polarization. The purpose of this exercise was twofold: firstly, to demonstrate that the new zero-field neutron spin-echo method will work also for very long neutron flight paths; secondly, to prove in the most direct way that the neutron free-flight region of the ILL neutron-antineutron oscillation experiment was indeed sufficiently field-free (“quasifree condition”) by using the neutrons themselves as a magnetometer. To this purpose the residual magnetic field integrals in the long “zero-field” region were measured with a conventional neutron spin-echo method. The overall spin precession angle of the neutrons during their flight through the long zero-field region was found to be less than 2°.  相似文献   
1000.
We present the results of an evaluation of the performance characteristics of a composite multivariate quality control (CMQC) system that incorporates quality control rules for univariate, multivariate, and correlation conditions. The CMQC system evaluated is designed to help analysts detect unacceptable trends and systematic error in one or more variables, unacceptable random error in one or more variables, and unacceptable changes in the correlation structure of any pair of variables. It is also designed to be tolerant of missing data, to allow analysts to reject as few as one or as many as all variables in a run, and to provide analysts with control statistics and graphics that logically relate to sources of analytical error. We show that the various components of the CMQC system have adequate statistical power to detect systematic errors, random errors, and correlation changes under the conditions likely to be encountered with multivariate analytical measurement systems: (1) a single variable with increased systematic or random error; (2) all variables or a subgroup of variables affected by a common problem that increases systematic or random error; and (3) missing data for one or more variables in a run. We also show that the power of the multivariate component of the CMQC system to detect systematic and random errors is higher than the power of an alternative multivariate test criterion.  相似文献   
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