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71.
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This paper examines the information available through leading indicators for modelling and forecasting the UK quarterly index of production. Both linear and non‐linear specifications are examined, with the latter being of the Markov‐switching type as used in many recent business cycle applications. The Markov‐switching models perform relatively poorly in forecasting the 1990s production recession, but a three‐indicator linear specification does well. The leading indicator variables in this latter model include a short‐term interest rate, the stock market dividend yield and the optimism balance from the quarterly CBI survey. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Botulinum toxin as a carrier for oral vaccines 总被引:1,自引:0,他引:1
Simpson LL Maksymowych AB Kiyatkin N 《Cellular and molecular life sciences : CMLS》1999,56(1-2):47-61
Botulinum toxin is an unusually potent substance that acts on the nervous system to produce the clinical outcome of flaccid
paralysis. To produce this effect, the toxin ordinarily proceeds through two separate but essential sequences of events. During
the first, the toxin is ingested, it traverses a portion of the gastrointestinal system and then it is transcytosed from the
lumen of the gut to the general circulation. During the second, circulating toxin binds to peripheral cholinergic nerve endings,
it is endocytosed and then it acts as a metalloendoprotease to cleave polypeptides that are essential for exocytosis. Although
botulinum toxin is antigenic, it ordinarily does not evoke an immune response during or after cases of oral poisoning. This
is due to the fact that the dose of toxin that produces flaccid paralysis—and potentially death—is less than the dose needed
to evoke an antibody response. In the recent past, the techniques of molecular biology have been used to generate an expression
product of botulinum toxin that retains the ability to escape the gut and reach the general circulation, retains the ability
to evoke an immune response, but has lost the ability to produce neurotoxicity. This modified toxin may have two clinical
applications. The expression product itself may have utility as an oral vaccine against botulism. Beyond this, the modified
toxin, or a truncation mutant of the toxin, may have utility as a carrier in the construction of other oral vaccines. Both
potential applications could lead to the expression of oral vaccines in common foods.
Received 29 December 1998; received after revision 22 March 1999; accepted 24 March 1999 相似文献
76.
J. S. Karliner T. Kagiya P. C. Simpson 《Cellular and molecular life sciences : CMLS》1990,46(1):81-84
Summary In neonatal rat ventricular myocytes pretreatment with pertussis toxin did not affect 1 M (–)-norepinephrine stimulation of inositol phosphates or myocardial cell hypertrophy as measured either by protein radiolabelling or by myocardial cell protein content. Thus guanine nucleotide protein (s) ADP-ribosylated by pertussis toxin do not play a role in two
1-adrenoceptor-mediated processes, phosphatidylinositide turnover and induction of myocardial cell hypertrophy. 相似文献
77.
Semaw S Simpson SW Quade J Renne PR Butler RF McIntosh WC Levin N Dominguez-Rodrigo M Rogers MJ 《Nature》2005,433(7023):301-305
Comparative biomolecular studies suggest that the last common ancestor of humans and chimpanzees, our closest living relatives, lived during the Late Miocene-Early Pliocene. Fossil evidence of Late Miocene-Early Pliocene hominid evolution is rare and limited to a few sites in Ethiopia, Kenya and Chad. Here we report new Early Pliocene hominid discoveries and their palaeoenvironmental context from the fossiliferous deposits of As Duma, Gona Western Margin (GWM), Afar, Ethiopia. The hominid dental anatomy (occlusal enamel thickness, absolute and relative size of the first and second lower molar crowns, and premolar crown and radicular anatomy) indicates attribution to Ardipithecus ramidus. The combined radioisotopic and palaeomagnetic data suggest an age of between 4.51 and 4.32 million years for the hominid finds at As Duma. Diverse sources of data (sedimentology, faunal composition, ecomorphological variables and stable carbon isotopic evidence from the palaeosols and fossil tooth enamel) indicate that the Early Pliocene As Duma sediments sample a moderate rainfall woodland and woodland/grassland. 相似文献
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Dickins RA Hemann MT Zilfou JT Simpson DR Ibarra I Hannon GJ Lowe SW 《Nature genetics》2005,37(11):1289-1295
79.
Collagenolytic activity of sarcoma tissues in culture 总被引:4,自引:0,他引:4
80.
Zusammenfassung Untersuchungen an Mandibel-, Hinterkopf- und Thoraxdrüsen der Bienenkönigin sowie an Thoraxdrüsen der Drohne haben gezeigt, dass sie, verglichen mit den Hypopharynxdrüsen der Arbeiterin, nur sehr wenig oder gar keine Invertase enthalten. Da weder Königin noch Drohne an der Honigspeicherung teilnehmen, brauchen sie keine Speicheldrüsen-Invertase. 相似文献