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1.
Myelotoxicity is the dose-limiting factor in radioimmunotherapy. Traditional methods most commonly used to estimate the radiation adsorbed dose to the bone marrow of patients consider contributions from radionuclide in the blood and/or total body. Targeted therapies, such as radioimmunotherapy, add a third potential source for radiation to the bone marrow because the radiolabeled targeting molecules can accumulate specifically on malignant target cells infiltrating the bone marrow. A non-invasive method for estimating the radiation absorbed dose to the red marrow of patients who have received radiolabeled monoclonal antibodies (MoAb) has been developed and explored. The method depends on determining the cumulated activity in three contributing sources: 1) marrow; 2) blood; and 3) total body. The novel aspect of this method for estimating marrow radiation dose is derivation of the radiation dose for the entire red marrow from radiation dose estimates obtained by detection of cumulated activity in three lumbar vertebrae using a gamma camera. Contributions to the marrow radiation dose from marrow, blood, and total body cumulated activity were determined for patients who received an I-131 labeled MoAb, Lym-1, that reacts with malignant B-lymphocytes of chronic lymphocytic leukemia and nonHodgkin's lymphoma. Six patients were selected for illustrative purposes because their vertebrae were readily visualized on lumbar images. The radiation doses to the marrow contributed by nonpenetrating emissions in the marrow blood and penetrating emissions in the total body were similar in these patients with a mean of 0.2 and 0.3 rads per administered mCi from the blood and total body, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Task scheduling is essential for the proper functioning of parallel processor systems. Scheduling of tasks onto networks of parallel processors is an interesting problem that is well-defined and documented in the literature. However, most of the available techniques are based on heuristics that solve certain instances of the scheduling problem very efficiently and in reasonable amounts of time. This paper investigates an alternative paradigm, based on genetic algorithms, to efficiently solve the scheduling problem without the need to apply any restricted assumptions that are problem-specific, such is the case when using heuristics. Genetic algorithms are powerful search techniques based on the principles of evolution and natural selection. The performance of the genetic approach will be compared to the well-known list scheduling heuristics. The conditions under which a genetic algorithm performs best will also be highlighted. This will be accompanied by a number of examples and case studies  相似文献   
3.
The findings are presented of a conference on Outcomes of Hand Surgery organized by the audit committee of British Society for Surgery of the Hand in 1993. Measures of outcome in terms of movement, power, sensibility, pain, activities of daily living, complications and patient satisfaction are considered, and an example of a patient evaluation measure given as an appendix.  相似文献   
4.
The paper firstly provides an introduction to the broadband call control demonstrator platform developed at BT Laboratories. It describes the basic connection level functionality used to give point-to-point and point-to-multipoint call demonstrations. It then describes the introduction of a Digital Audio-Visual Council (DAVIC)-conformant session control capability and how this is used as the basis of a more comprehensive demonstration. The paper also examines how future networking concepts such as object orientation and distributed processing environments are being introduced, in particular the interworking between DAVIC and Telecommunications Information Network Architecture Consortium (TINA-C) approaches. Finally, some of the evolutionary aspects of the broadband call control demonstrator platform are introduced.  相似文献   
5.
Reduction in wort anthocyanogen content is achieved effectively when formaldehyde is introduced to the mash at the beginning of the mashing operation. Concentrations of 50 p.p.m. of formaldehyde with respect to the malt (equivalent to about 5 p.p.m. with respect to the final wort volume) are effective in reducing the anthocyanogen content by about 30%. Treatments four times as strong reduce the anthocyanogen content by 60–70%, and the effect is accompanied by a fall of up to 10% in the soluble nitrogen content of the wort. It seems likely that a condensation reaction occurs between anthocyanogens and a nitrogenous fraction of the wort. Under the conditions quoted, formaldehyde residues in the finished beers are less than 0·2 p.p.m. and are no greater than those observed in corresponding untreated control beers. Beers produced from treated mashes exhibit great non-biological stability, but are quite normal in other respects. The effect of formaldehyde on the anthocyanogen contents of worts and beers is of substantial theoretical interest and it is probable that it will also have a commercial application.  相似文献   
6.
1,25-dihydroxyvitamin D3 (1,25(OH)2D3), gamma interferon (IFN-gamma) and granulocyte-macrophage colony-stimulating factor (GM-CSF) can regulate monocyte maturation and activation. Using the human monocytoid cell line U937, we have shown that these agents increase surface tumor necrosis factor (TNF) expression without directly affecting TNF release. GM-CSF and IFN-gamma combined with 1,25(OH)2D3 increased cellular TNF secretion to levels not seen with these agents alone. Ability to express and secrete TNF in part depended on degree of monocytic maturation. The combination of 1,25(OH)2D3 and GM-CSF, however, facilitated lipopolysaccharide (LPS)-mediated release of surface TNF from U937 cells, an effect that was temporally independent of maximal maturation. 1,25(OH)2D3 plus IFN-gamma was less effective than 1,25(OH)2D3 plus GM-CSF at facilitating TNF secretion. We postulate that 1,25(OH)2D3 and GM-CSF are required together to prime a specific mechanism, probably a protease, which cleaves TNF from the surface of monocytic cells. This protease, once primed, can be activated by a secondary stimulus such as LPS.  相似文献   
7.
A phylogenetic tree for major lineages of iguanian lizards is estimated from 1,488 aligned base positions (858 informative) of newly reported mitochondrial DNA sequences representing coding regions for eight tRNAs, ND2, and portions of ND1 and COI. Two well-supported groups are defined, the Acrodonta and the Iguanidae (sensu lato). This phylogenetic hypothesis is used to investigate evolutionary shifts in mitochondrial gene order, origin for light-strand replication, and secondary structure of tRNACys. These three characters shift together on the branch leading to acrodont lizards. Plate tectonics and the fossil record indicate that these characters changed in the Jurassic. We propose that changes to the secondary structure of tRNACys may destroy function of the origin for light-strand replication which, in turn, may facilitate shifts in gene order.  相似文献   
8.
Chitons are marine molluscs that mineralize their teeth by the process of matrix‐mediated biomineralization. The teeth develop in a continuous manner forming hard minerals, including magnetite, making analysis of the matrix within these mineralized regions difficult. This article describes the use of charge contrast imaging techniques, rarely applied to biological samples, to simultaneously image the organic and mineral phases within the teeth of these animals. Resulting evidence demonstrates the power of this technique in delivering architectural information concerning both the matrix and mineral phases, without the need for removal of the hard mineralized material. SCANNING 31: 11–18, 2009. © 2009 Wiley Periodicals, Inc.  相似文献   
9.
This article describes effects of the birth of a premature infant on the family system and focuses on how problems associated with premature birth such as infant illness, hospitalization, and immaturity can place the family at risk. New data are presented describing differences in the behavior of preterm and full-term infants and in the feelings of mothers toward their infants at 12 months. Mothers of preterm infants reported feeling overprotective toward them, were less willing to leave them with sitters, and believed that their birth had an initially negative effect on the family. Preterm infants showed less exploratory play and stayed closer to their mothers during free play. The fact that these differences are not reflected in patterns of attachment, a key measure of the mother–infant relationship, is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
An Assessment of MPI Environments for Windows NT   总被引:1,自引:0,他引:1  
In this paper we evaluate the MPI environments currently available for Windows NT on the Intel IA32 and Compaq/DEC Alpha architectures. We present benchmark results for low-level communication and for the NAS Parallel Benchmarks to allow comparison with other systems, but our primary interest is determining real application performance and robustness in production cluster environments. For this we use PAFEC-FE, a large FORTRAN code for finite-element analysis. We present results from three MPI implementations, two architectures, and three networking technologies (10 and 100 Mbit/s Ethernet and 1 Gbit/s Myrinet).  相似文献   
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