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NG Nossal 《Canadian Metallurgical Quarterly》1998,148(4):1535-1538
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二氧化碳降解塑料产业前景广阔 总被引:4,自引:0,他引:4
阐述了国内外二氧化碳降解塑料的研发生产现状,分析了它的市场前景,并提出了建议. 相似文献
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A multisite, longitudinal study of patients undergoing inpatient alcohol and drug dependence treatment was conducted in private inpatient facilities, consisting of 4339 subjects from 38 independent programs enrolled in a national addiction treatment outcomes registry. Structured interviews were conducted upon admission, including documentation of current alcohol/drug disorder (DSM-III-R) and lifetime diagnosis of major depressive syndrome; structured interviews were conducted prospectively at 6- and 12-month follow-up periods. The prevalence rate of lifetime diagnosis of major depression in the sample was 39%. Comorbidity varied according to gender and substance of choice. Lifetime depressive symptoms did not correlate with differential length-of-stay, treatment completion, or follow-up consent and, at best, were very weakly associated with follow-up contact. Patients diagnosed with lifetime depression showed the same frequency of participation in posttreatment continuing care: they also showed statistically significant reductions in job absenteeism, inpatient hospitalizations, and arrest rates pre- vs. posttreatment comparable to those of patients without lifetime depression diagnosis. Lifetime major depressive syndrome was not a predictor of outcome in response to abstinence-based treatment. Involvement in posttreatment continuing care accounted for far greater outcome variance. Posttreatment vs. pretreatment factors may be more decisive in influencing risk for relapse. 相似文献
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Recent advances in the understanding of the biomechanics of the elbow and improvement in material designs have revolutionized the ability to treat difficult problems of the proximal interphalangeal and elbow joints. Dynamic skeletal fixation addresses the desire to allow an injured joint to heal, move, and remain stable simultaneously. In the past, such goals were achieved sequentially or in series. It is now possible to perform such tasks in parallel. 相似文献
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The Staphylococcus aureus 8325-4 hyaluronate lyase gene (hysA) was identified after detecting hyaluronate lyase activity expressed by phages from a genomic library. The hysA open reading frame, capable of encoding a protein of 91 980 Da, was identified by Tn5 mutagenesis and nucleotide sequencing. HysA shares 35 and 36% amino acid sequence identity with group B streptococcal hyaluronate lyase and pneumococcal hyaluronidase, respectively. A 94-kDa protein was expressed in Escherichia coli minicells, a result consistent with the coding capacity of hysA. Identification of the S. aureus 8325-4 hyaluronate lyase gene will allow the regulation of this putative virulence determinant to be studied. 相似文献
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