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51.
The yeast Saccharomyces cerevisiae can synthesize, process and secrete higher eukaryotic proteins. We have investigated the expression of immunoglobulin chains in yeast and demonstrate here the synthesis, processing and secretion of light and heavy chains, the glycosylation of heavy chain, the intracellular localization of these foreign proteins by immunofluorescence, and the detection of functional antibodies in cells co-expressing both chains. This may provide the basis of a microbial fermentation process for the production of monoclonal antibodies. The co-expression of light and heavy chains in Escherichia coli has been reported but functional antibodies were not assembled in vivo. Furthermore, only low-level assembly of these chains was found in vitro. 相似文献
52.
Effect of long acting somatostatin-analogue, SMS 201 995, on gut hormone secretion in normal subjects 总被引:1,自引:0,他引:1
SMS 201 995 is a new long acting analogue of somatostatin. We have investigated its effect on basal and meal stimulated secretion of gut hormones and have shown that after a single s.c. injection of 50 micrograms it lowers significantly the basal plasma levels of pancreatic polypeptide, secretin, motilin, pancreatic glucagon and insulin, it also effectively suppresses the postprandial release of pancreatic polypeptide, gastrin, secretin, gastric inhibitory peptide, pancreatic glucagon and insulin. Except for the usual brief discomfort of an injection, no symptoms or untoward effects were observed. 相似文献
53.
Locomotor affinities of Hominoid tali from Kenya 总被引:1,自引:0,他引:1
54.
Endothelin-1 synthesis reduced by red wine. 总被引:14,自引:0,他引:14
R Corder J A Douthwaite D M Lees N Q Khan A C Viseu Dos Santos E G Wood M J Carrier 《Nature》2001,414(6866):863-864
Statistical evidence of reduced coronary heart disease in areas of high wine consumption has led to the widespread belief that wine affords a protective effect. Although moderate drinking of any alcohol helps to reduce the incidence of coronary heart disease, there is no clear evidence that red wine confers an additional benefit. Here we show that red wines strongly inhibit the synthesis of endothelin-1, a vasoactive peptide that is crucial in the development of coronary atherosclerosis. Our findings indicate that components specific to red wine may help to prevent coronary heart disease. 相似文献
55.
56.
Pseudoxylechinus , new genus, and uniformis (type-species) (Yunnan), variegatus (Sanxi), sinensis (Yunnan), rugatus (Yunnan), and tibetensis (Tibet), new species, are described. Kissophagus tiliae Niisima, 1910, is also transferred to this genus. 相似文献
57.
Stephen L. Wood 《西北部美国博物学家》2011,52(1)
In Platypodidae the new name Genyocerus strohmeyeri replaced the junior homonym G. albipennis Strohmeyer, 1942, and the new name Platypus applanatulus replaced the junior homonym Platypus applanatus Schedl, 1976. New names are presented in Scolytidae as replacements for junior homonyms as follows: Cryphalus brownei for Cryphalus artocarpus Schedl, 1958; Cyclorhipidion dihingicum for Xyleborus dihingensis Schedl, 1951; Hypothenemus aterrimulus for Lepiceroides (now Hypothenemus ) aterrimus Schedl, 1957; Hypothenemus krivolutskayae for Hypothenemus insularis Krivolutskaya; Pityophthorus africanulus for Neodryocoetes (now Pityophthorus ) africanus Schedl, 1962; Scolytogenes papuensis for Xylocryptus (now Scolytogenes ) papuanus Schedl, 1975; Scolytogenes paradoxus for Scolytogenes papuanus Schedl, 1979; Xyleborinus spiniposticus for Eidophelus (now Xyleborinus ) spinipennis Schedl, 1979; Xyleborus formosae for Xyleborus formosanus Browne, 1981. New combinations for fossil Scolytidae include Dryocoetes diluvialis for Pityophthoroidea diluvialis Wickham, 1916, and Hylesinus hydropicus for Apidocephalus hydropicus Wickham, 1916. Phloeotribus zimmermanni Wickham, 1916, is transferred to the family Curculionidae. In Scolytidae, Cryphalophilus Schedl, 1970, is a junior generic synonym of Scolytogenes Eichhoff; Macrocryphalus Nobuchi, 1981, is a junior generic synonym of Hypothenemus Westwood, 1836; Nipponopolygraphus Nobuchi, 1981, is a junior generic synonym of Polygraphus Erichson, 1836; Pseudocosmoderes Nobuchi, 1981, is a junior generic synonym of Cosmoderes Eichhoff, 1878; Taphrocoetes Pfeffer, 1987, is a junior generic synonym of Taphrorychus Eichhoff; Trypanophellos Bright, 1982, is a junior generic synonym of Liparthrum Wollaston. New specific synonymy in Scolytidae includes: Brachyspartus moritzi Ferrari (= Corthylus obtusus Schedl), Carphoborus minimus (Fabricius) (= Carphobhorus balgensis Murayama), Coccotrypes dactyliperda (Fabricius) (= Coccotrypes tropicus Eichhoff), Cryphalus scabricollis Eichhoff (= Cryphalus brevicollis Schedl), Ficicis despects (Walker) (= Hylesinus samoanus Schedl), Hylastes plumbeus Blandford (= Hylurgops fushunensis Murayama), Hylurgops interstitialis (Chapuis) (= Hylurgops niponicus Murayama), Hylurgops spessivtsevi Eggers (= Hylurgops modestus Murayama), Ips stebbingi Strohmeyer (= Ips schmutzenhoferi Holzschuh), Phloeosinus rudis Blandford (= Phloeosinus shotoensis Murayama, Polygraphus kaimochi (Nobuchi) (= Polygraphus querci Wood), Polygraphus proximus Blandford (= Polygraphus magnus Murayama), Scolytogenes braderi Browne (= Scolytogenes orientalis Schedl), Scolytoplatypus parvus Sampson (= Scolytoplatypus ruficauda Eggers), Sphaerotrypes querci Stebbing (= Chramesus globulus Stebbing, Sphaerotrypes tectus Beeson), Sueus niisimai (Eggers) (= Sphaerotrypes controversae Murayama), Tomicus brevipilosus (Eggers) (= Blastophagus khasianus Murayama, Blastophagus multisetosus Murayama). The European Hylastes opacus Erichson is reported as an established breeding population in New York (USA). Phloeosinus armatus Reitter of Asia Minor is reported as causing economic damage as a new introduction to Los Angeles County, California. The following species are named as new to science: Cyclorhipidion subagnatum (Philippine Islands), Dendrotrupes zealandicus (New Zealand), Polygraphus thitsi (Burma), Triotemnus pilicornis (India), and Xyleborus mangificus (Peru). 相似文献
58.
The influence of winter weather on the survival of Utah's ring-necked pheasants was evaluated using correlation analysis. This method used published Utah State Division of Wildlife Resources population data and a calculated winter warmth index. Results show four different patterns of survival occurring in the 14 counties analyzed. 相似文献
59.
Regular, moderate consumption of red wine is linked to a reduced risk of coronary heart disease and to lower overall mortality, but the relative contribution of wine's alcohol and polyphenol components to these effects is unclear. Here we identify procyanidins as the principal vasoactive polyphenols in red wine and show that they are present at higher concentrations in wines from areas of southwestern France and Sardinia, where traditional production methods ensure that these compounds are efficiently extracted during vinification. These regions also happen to be associated with increased longevity in the population. 相似文献
60.
Pepys MB Hirschfield GM Tennent GA Gallimore JR Kahan MC Bellotti V Hawkins PN Myers RM Smith MD Polara A Cobb AJ Ley SV Aquilina JA Robinson CV Sharif I Gray GA Sabin CA Jenvey MC Kolstoe SE Thompson D Wood SP 《Nature》2006,440(7088):1217-1221
Complement-mediated inflammation exacerbates the tissue injury of ischaemic necrosis in heart attacks and strokes, the most common causes of death in developed countries. Large infarct size increases immediate morbidity and mortality and, in survivors of the acute event, larger non-functional scars adversely affect long-term prognosis. There is thus an important unmet medical need for new cardioprotective and neuroprotective treatments. We have previously shown that human C-reactive protein (CRP), the classical acute-phase protein that binds to ligands exposed in damaged tissue and then activates complement, increases myocardial and cerebral infarct size in rats subjected to coronary or cerebral artery ligation, respectively. Rat CRP does not activate rat complement, whereas human CRP activates both rat and human complement. Administration of human CRP to rats is thus an excellent model for the actions of endogenous human CRP. Here we report the design, synthesis and efficacy of 1,6-bis(phosphocholine)-hexane as a specific small-molecule inhibitor of CRP. Five molecules of this palindromic compound are bound by two pentameric CRP molecules, crosslinking and occluding the ligand-binding B-face of CRP and blocking its functions. Administration of 1,6-bis(phosphocholine)-hexane to rats undergoing acute myocardial infarction abrogated the increase in infarct size and cardiac dysfunction produced by injection of human CRP. Therapeutic inhibition of CRP is thus a promising new approach to cardioprotection in acute myocardial infarction, and may also provide neuroprotection in stroke. Potential wider applications include other inflammatory, infective and tissue-damaging conditions characterized by increased CRP production, in which binding of CRP to exposed ligands in damaged cells may lead to complement-mediated exacerbation of tissue injury. 相似文献