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991.
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J.Edward Semple David C. Rowley Timothy D. Owens Nathaniel K. Minami Theresa H. Uong Terence K. Brunck 《Bioorganic & medicinal chemistry letters》1998,8(24):1525-3530
Crystal structure and evolving SAR considerations of potent, selective benzylsulfonamide lactam thrombin inhibitors and related serine protease inhibitors have led to the design of novel thrombin inhibitors 1a-g, featuring hydrophobic, basic, P4-alkylaminolactam scaffolds that serve as novel types of P3---P4 dipeptide mimics. The design, synthesis, and biological activity of these targets is presented. 相似文献
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R E Ryder D R Owens T M Hayes M A Ghatei S R Bloom 《BMJ (Clinical research ed.)》1990,301(6755):783-787
OBJECTIVE--To examine the traditional view that unawareness of hypoglycaemia and inadequate hypoglycaemic counterregulation in insulin dependent diabetes mellitus are manifestations of autonomic neuropathy. DESIGN--Perspective assessment of unawareness of hypoglycaemia and detailed assessment of autonomic neuropathy in patients with insulin dependent diabetes according to the adequacy of their hypoglycaemic counterregulation. SETTING--One routine diabetic unit in a university teaching hospital. PATIENTS--23 Patients aged 21-52 with insulin dependent diabetes mellitus (seven with symptoms suggesting autonomic neuropathy, nine with a serious clinical problem with hypoglycaemia, and seven without symptoms of autonomic neuropathy and without problems with hypoglycaemia) and 10 controls with a similar age distribution, without a personal or family history of diabetes. MAIN OUTCOME MEASURES--Presence of autonomic neuropathy as assessed with a test of the longest sympathetic fibres (acetylcholine sweatspot test), a pupil test, and a battery of seven cardiovascular autonomic function tests; adequacy of hypoglycaemic glucose counterregulation during a 40 mU/kg/h insulin infusion test; history of unawareness of hypoglycaemia; and response of plasma pancreatic polypeptide during hypoglycaemia, which depends on an intact and responding autonomic innervation of the pancreas. RESULTS--There was little evidence of autonomic neuropathy in either the 12 diabetic patients with a history of unawareness of hypoglycaemia or the seven patients with inadequate hypoglycaemic counterregulation. By contrast, in all seven patients with clear evidence of autonomic neuropathy there was no history of unawareness of hypoglycaemia and in six out of seven there was adequate hypoglycaemic counterregulation. Unawareness of hypoglycaemia and inadequate hypoglycaemic counterregulation were significantly associated (p less than 0.01). The response of plasma pancreatic polypeptide in the diabetic patients with adequate counterregulation but without autonomic neuropathy was not significantly different from that of the controls (change in plasma pancreatic polypeptide 226.8 v 414 pmol/l). The patients with autonomic neuropathy had a negligible plasma pancreatic polypeptide response (3.7 pmol/l), but this response was also blunted in the patients with inadequate hypoglycaemic counterregulation (72.4 pmol/l) compared with that of the controls (p less than 0.05). CONCLUSIONS--Unawareness of hypoglycaemia and inadequate glucose counterregulation during hypoglycaemia are related to each other but are not due to autonomic neuropathy. The blunted plasma pancreatic polypeptide responses of the patients with inadequate hypoglycaemic counterregulation may reflect diminished autonomic activity consequent upon reduced responsiveness of a central glucoregulatory centre, rather than classical autonomic neuropathy. 相似文献
996.
J. L. Gonzalez-Hernandez G. Sarath J. M. Stein V. Owens K. Gedye A. Boe 《In vitro cellular & developmental biology. Plant》2009,45(3):267-281
Due to the rapid rate of worldwide consumption of nonrenewable fossil fuels, production of biofuels from cellulosic sources
is receiving increased research emphasis. Here, we review the feasibility to produce lignocellulosic biomass on marginal lands
that are not well-suited for conventional crop production. Large areas of these marginal lands are located in the central
prairies of North America once dominated by tallgrass species. In this article, we review the existing literature, current
work, and potential of two native species of the tallgrass prairie, prairie cordgrass (Spartina pectinata), and little bluestem (Schizachyrium scoparium) as candidates for commercial production of biofuel. Based on the existing literature, we discuss the need to accelerate
research in the areas of agronomy, breeding, genetics, and potential pathogens. Cropping systems based on maintaining biodiversity
across landscapes are essential for a sustainable production and to mitigate impact of pathogens and pests. 相似文献
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Rossi P Aramini JM Xiao R Chen CX Nwosu C Owens LA Maglaqui M Nair R Fischer M Acton TB Honig B Rost B Montelione GT 《Proteins》2009,74(2):515-519
999.
Richard B. Hitchman Robert D. Possee Andrew T. Crombie Adam Chambers Kim Ho Evangelia Siaterli Olga Lissina Heather Sternard Robert Novy Kathryn Loomis Louise E. Bird Raymond J. Owens Linda A. King 《Cell biology and toxicology》2010,26(1):57-68
Generating large amounts of recombinant protein in transgenic animals is often challenging and has a number of drawbacks compared to cell culture systems. The baculovirus expression vector system (BEVS) uses virus-infected insect cells to produce recombinant proteins to high levels, and these are usually processed in a similar way to the native protein. Interestingly, since the development of the BEVS, the virus most often used (Autographa californica multi-nucleopolyhedovirus; AcMNPV) has been little altered genetically from its wild-type parental virus. In this study, we modified the AcMNPV genome in an attempt to improve recombinant protein yield, by deleting genes that are non-essential in cell culture. We deleted the p26, p10 and p74 genes from the virus genome, replacing them with an antibiotic selection cassette, allowing us to isolate recombinants. We screened and identified recombinant viruses by restriction enzyme analysis, PCR and Western blot. Cell viability analysis showed that the deletions did not improve the viability of infected cells, compared to non-deletion viruses. However, expression studies showed that recombinant protein levels for the deletion viruses were significantly higher than the expression levels of non-deletion viruses. These results confirm that there is still great potential for improving the BEVS, further increasing recombinant protein expression yields and stability in insect cells. 相似文献
1000.