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The past year has seen significant advances in our understanding of the mechanism of RNA movement between the nucleus and the cytoplasm. The emerging view is that proteins bind to and escort RNAs to their proper subcellular location. The discovery of peptide signals that target nuclear export and the identification of novel protein mediators of RNA export are examples of significant recent discoveries. 相似文献
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Two glial cell types surround olfactory axons and glomeruli in the olfactory bulb (OB) and may influence synapse development and regeneration. OB astrocytes resemble type-1 astrocytes, and OB ensheathing cells resemble non-myelinating Schwann cells. We have produced clonal OB astrocyte and ensheathing cell lines from rat neonatal and adult OB cultures by SV40 large T antigen transduction. These cell lines have been characterized by morphology, growth characteristics, immunophenotype, and ability to promote neurite outgrowth in vitro. Neonatal and adult ensheathing cell lines were found to support higher neurite outgrowth than OB astrocyte lines. Neonatal OB astrocyte lines were of two types, high and low outgrowth support. The low support astrocyte lines express J1 and a chondroitin sulfate-containing proteoglycan as do astrocytes encircling the neonatal glomeruli in vivo. The adult OB astrocyte cell lines supported lower levels of outgrowth than adult ensheathing cell lines. These results are consistent with a positive role for ensheathing cells in OB synapse regeneration, in vivo. Further, based on our results, we hypothesize that ensheathing cells and high-outgrowth astrocytes facilitate axon growth in vivo, while low outgrowth astrocytes inhibit axon growth and may facilitate glomerulus formation. 相似文献
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Durand D.J. Sandell R.D. Heflinger L. Silver A.H. 《Applied Superconductivity, IEEE Transactions on》1992,2(2):106-110
Single-flux quantum devices are used in superconductive analog-to-digital converters (ADCs), shift registers, and memory cells. They have been proposed for logic applications. The authors report the performance of high-speed superconducting, single-flux quantum (SFQ) ripple counters. Both memory and logic functions of the counter are investigated. Errors in logic operation produce bit error rates (BERs) as low as 0.22 errors per million binary operations, measured while counting 100-MHz pseudorandom input pulses. Errors in memory function do not occur on the time scale of the measurements. The BER is shown to be nearly independent of input bit rate and pattern, but strongly dependent on the counter cell operating point 相似文献
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Rattok Jack; Ross Barbara; Ben-Yishay Yehuda; Ezrachi Ora; Silver Saralyn; Lakin Phyllis; Vakil Eli; Piasetsky Eugene; Zide Ellen; Diller Leonard 《Canadian Metallurgical Quarterly》1992,6(4):395
Within a clinical demonstration program, 59 traumatically brain-injured patients were treated with 1 of 3 mixes of treatment. Mix 1 included cognitive remediation (CGR), small-group interpersonal (SGI) communication training, therapeutic community activities, and personal counseling. Mix 2 was similar to Mix 1 but stressed SGI exercises and eliminated CGR. Mix 3 emphasized CGR and eliminated SGI exercises. The efficacy of the treatment mixes was evaluated with performance on neuropsychological tests, improved independence in functional activities, measures of intra- and interpersonal functioning, and vocational outcome. Ss' participation in the program, irrespective of treatment mix, yielded improvements in (1) self-image, (2) quality of interpersonal relatedness and interaction, (3) involvement with others in naturalistic settings, and (4) vocational outcome. Overall, data point to the superiority of the balanced mix (Mix 1) over Mixes 2 and 3. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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McIntosh Daniel N.; Silver Roxane Cohen; Wortman Camille B. 《Canadian Metallurgical Quarterly》1993,65(4):812
Parents (N?=?124) who had lost an infant to sudden infant death syndrome were interviewed 3 wks and 18 mo postloss. Two components of religion (religious participation and religious importance) were assessed, and their relations with 3 coping-process variables (perceived social support, cognitive processing of the loss, and finding meaning in the death) were examined. Greater religious participation was related to increased perception of social support and greater meaning found in the loss. Importance of religion was positively related to cognitive processing and finding meaning in the death. Furthermore, through these coping-process variables, religious participation and importance were indirectly related to greater well-being and less distress among parents 18 mo after their infants' deaths. Results suggest that further study of the social and cognitive aspects of religion would be profitable. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The purpose of this study was to characterize quality of care problems among Medicare and Medicaid inpatients in New York State. The patients selected for this study comprised 1991 and 1992 Medicare and all 1992 Medicaid inpatients in whom quality of care problems with actual or potential adverse effects were found. The patients in this study were drawn from public, proprietary, voluntary and teaching hospitals. A total of 1000 quality of care problems with either actual or potential adverse effects were found in 706 Medicare patients. Two hundred and seventy-five (275) quality of care problems with actual or potential adverse effects were found in 154 Medicaid patients. Premature death occurred in 53 (7.4%) of the 706 Medicare and in 42 (27.2%) of the 154 Medicaid patients. Treatment problems and monitoring failures accounted for the majority of quality of care problems with actual or potential adverse effects for both Medicare (63.0%) and Medicaid (75.7%) patients. Among Medicare patients, the treatment of infections and antibiotic use, fluid and electrolyte management, and inappropriate drug use were among the leading causes of quality of care problems. Attending physicians were associated with the majority of Medicare quality of care problems while house staff and attending physicians were associated with the majority of those among Medicaid patients. The results of this study indicate that there are several leading causes of quality of care problems among Medicare and Medicaid patients. Treatment problems and monitoring failures together comprise the majority of such problems. Among Medicare patients, it was found that most quality of care problems were associated with the treatment of infections and antibiotic use, fluid and electrolyte management, and inappropriate drug use. Most quality of care problems among Medicaid patients were associated with these categories as well as with labor and delivery problems, and poor discharge planning. The results of this study reflect the peer-review process in which providers are given an opportunity to respond to physician-reviewer decisions about the presence of actual or potential adverse effects. Such a process, which permits the presentation of additional data and information by providers, produces fewer final adverse outcome determinations than a process uniquely based on chart review. The quality of care problems observed in this study are amenable to focused educational interventions. Such remedial interventions could yield significant improvements in the quality of care for all patients. 相似文献
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