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排序方式: 共有1314条查询结果,搜索用时 484 毫秒
71.
The Effect of Compaction Force and Type of Pregelatinized Starch on the Dissolution of Acetaminophen
The influence of four pregelatinized starches—National® 1551, Lycatabps, Pregeflo®M, and Starch 1500®—as binders, on the dissolution of acetaminophen was evaluated in a model wet-granulated system. Systems containing 82% acetaminophen were prepared under the same processing conditions and compacted to three target tablet thicknesses. The dissolution performance was assessed using a point estimate of percent dissolved at 30 min (%T30) as well as dissolution eflciency through 30 min (DE30). All four binders evaluated meet USP requirements for purity. National 1551, Lycatab PGS, and Starch 1500 were not affected by compaction force in terms of dissolution performance. Differences were observed between the fully pregelatinized systems of National 1551 and Lycatab PGS, in comparison to the partially pregelatinized system, Starch 1500. The Pregeflo M starch produced a system with delayed drug dissolution and was influenced by compaction force. 相似文献
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WT Sholl 《Canadian Metallurgical Quarterly》1997,182(11):407-408
Following the fiftieth anniversary of the National Health Service Act 1946, I make the case in this article that professional provision of health care must remain the property of the citizen under common law and must not become a commodity that is bought and sold by third parties, including the state. 相似文献
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Bendov O. Browne J.F.X. Rhodes C.W. Wu Y. Bouchard P. 《Broadcasting, IEEE Transactions on》2001,47(3):207-217
It is now clear that methods used to predict the replication of the NTSC service in the United States were idealized and, for the most part, not validated. The need to review the methods and procedures now in use is highlighted by the various field tests conducted in the U.S. and elsewhere. This paper outlines potential improvements in the modeling, methods and procedures now in use for prediction and measurement of the DTV service 相似文献
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C. G. Rhodes M. S. Vassiliou M. R. Mitchell R. A. Spurling 《Metallurgical and Materials Transactions A》1990,21(6):1589-1593
Explosive shock-wave consolidation has been used to fabricate a composite consisting of gamma phase titanium aluminide matrix
reinforced with paniculate silicon carbide. Although the consolidation process takes less than a microsecond to complete,
melting of the surfaces of the titanium aluminide powder particles results in a reaction with the silicon carbide. Titanium
suicide and titanium carbide form in the molten zone, depleting it of titanium to the extent that its final composition is
TiAl3. In addition, a second titanium suicide phase forms on the surfaces of the silicon carbide particles.
This paper is based on a presentation made in the symposium “Interfaces and Surfaces of Titanium Materials” presented at the
1988 TMS/AIME fall meeting in Chicago, Illinois, September 25–29, 1988, under the auspices of the TMS Titanium Committee. 相似文献
80.
Yuan Zhou Yongzheng He Richa Sharma Wen Xing Selina A. Estwick Xiaohua Wu Steven D. Rhodes Mingjiang Xu Feng-Chun Yang 《International journal of molecular sciences》2015,16(6):12345-12359
Neurofibromatosis type 1 (NF1) is an autosomal dominant disease caused by mutations in the NF1 tumor suppressor gene, which affect approximately 1 out of 3000 individuals. Patients with NF1 suffer from a range of malignant and nonmalignant manifestations such as plexiform neurofibromas and skeletal abnormalities. We previously demonstrated that Nf1 haploinsufficiency in mesenchymal stem/progenitor cells (MSPCs) results in impaired osteoblastic differentiation, which may be associated with the skeletal manifestations in NF1 patients. Here we sought to further ascertain the role of Nf1 in modulating the migration and adhesion of MSPCs of the Nf1 haploinsufficient (Nf1+/−) mice. Nf1+/− MSPCs demonstrated increased nuclear-cytoplasmic ratio, increased migration, and increased actin polymerization as compared to wild-type (WT) MSPCs. Additionally, Nf1+/− MSPCs were noted to have significantly enhanced cell adhesion to fibronectin with selective affinity for CH271 with an overexpression of its complimentary receptor, CD49e. Nf1+/− MSPCs also showed hyperactivation of phosphoinositide 3-kinase (PI3-K) and mitogen activated protein kinase (MAPK) signaling pathways when compared to WT MSPCs, which were both significantly reduced in the presence of their pharmacologic inhibitors, and PD0325901, respectively. Collectively, our study suggests that both PI3-K and MAPK signaling pathways play a significant role in enhanced migration and adhesion of Nf1 haploinsufficient MSPCs. LY294002相似文献