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1.
2.
D A Nickson M W McBride S Zeinali C S Hawes A Petropoulos U W Mueller R G Sutcliffe 《Journal of reproduction and fertility》1991,93(1):149-156
The monoclonal antibody FDO161G reacts with a 43-kDa protein found in human extravillous trophoblast, syncytiotrophoblast, adrenal cortex, interstitial cells of the testis and ovarian follicle cumulus cells. cDNAs for this protein have been isolated from the lambda gt11 library, sequenced, and expressed in COS-7 cells. The protein was identified as 3 beta-hydroxy-5-ene steroid dehydrogenase (HSD). The sequence of the HSD protein raises questions about its association with cell membrane systems. The lack of reactivity of FDO161G with other tissues suggests that HSD has a limited tissue distribution and that other enzymes may exist in peripheral tissues, which can convert delta 5 3-hydroxysteroids to delta 4 3-ketosteroids. 相似文献
3.
A. V. Shakhbazau G. A. Yakovleva I. A. Rod’kina N. A. Kartel 《Cytology and Genetics》2008,42(2):75-80
The pleiotropic effects of transgenesis includes different consequences of the insertion of a transgene that are not related to the direct action of its product. It is necessary to evaluate the outlook for the application in selection of the transgenic potato strain containing the bacterial chitinase gene chiA we created for studying the possible nonspecific influence of the introduction of the transgene on the phenotypical properties of the transgenic lines. In the present investigation we will consider the effect of the introduction of the chitinase transgene on such agronomically important characteristics as yield and nonspecific resistance. 相似文献
4.
A single-vial assay has been developed for N-acetylglucosamine-6-phosphate deacetylase, in which [3H]acetate released from 3H-acetyl-labeled substrate is measured in a biphasic liquid scintillation counting system after acidification of the reaction mixture. The deacetylase was partially purified from rat liver, and some of its properties were determined. Chromatography on a calibrated Sepharose CL-6B column indicated a molecular weight of 345,000. The Km for the substrate at pH 8.0 was 0.3 mM. Glucosamine 6-phosphate and glucose 6-phosphate inhibited the enzyme, whereas N-acetylgalactosamine, N-acetylglucosamine, N-acetylglucosamine 1-phosphate, and glucosamine 1-phosphate were without effect. The effects of several divalent cations were also examined. Under the conditions tested, Ca2+, Mg2+, and Ba2+ had essentially no effect, whereas Mn2+, Ni2+, and Cu2+ were inhibitory and Co2+ stimulated activity at low concentrations but inhibited above 5 mM. An increase in the ionic strength of the reaction mixture to 0.3 M decreased the activity by 40%. 相似文献
5.
Göran Ekborg Martin Klinger Lennart Rodén John Wjesen John S Schutzbach Dee H Huang N Rama Krishna Gattadalli M Anantharamaiah 《Glycoconjugate journal》1987,4(3):255-266
3-O-β-d-Xylopyranosyl-l-serine (xylosylserine) was synthesized by the following three-step procedure: 1) 2,3,4-tri-O-benzoyl-α-d-xylopyranosyl bromide (benzobromoxylose) was condensed withN-carbobenzoxy-l-serine benzyl ester using the silver triflate-collidine complex as promoter; 2) theN-carbobenzoxy and benzyl ester groups in the resultant glycoside were cleaved by transfer hydrogenation with palladium black as catalyst and ammonium formate as hydrogen donor; and 3) the benzoyl groups were removed with methanolic ammonia. Xylosylserine was obtained in an overall yield of 70%. O-β-d-Galactopyranosyl-(1-4)-O-β-d-xylopyranosyl-(1-3)-l-serine (galactosylxylosylserine) was also synthesized by this methodology and was characterized by 2-dimensional (2D) NMR spectroscopy techniques. The two serine glycosides (xylosylserine and galactosylxylosylserine) were used in detection and partial purification of galactosyltransferase I (UDP-d-galactose:d-xylose galactosyltransferase) from adult rat liver. 相似文献
6.
Atypical nucleosome spacing of rat neuronal identifier elements in non-neuronal chromatin. 总被引:1,自引:1,他引:0
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Rat neuronal identifier (ID) elements are located in chromatin regions that are organized in nucleosomal structures in both neuronal and non-neuronal cells. A subpopulation of ID sequences in chromatin of liver and kidney cells are relatively resistant to micrococcal nuclease digestion and are organized in nucleosomes exhibiting an atypically short repeat length. Other repetitive elements do not show this organization. 相似文献
7.
Isolation and expression of an anther-specific gene from tomato 总被引:31,自引:0,他引:31
David Twell Rod Wing Judy Yamaguchi Sheila McCormick 《Molecular & general genetics : MGG》1989,217(2-3):240-245
8.
Rod Peakall 《Oecologia》1989,79(3):361-365
Summary The orchid Prasophyllum fimbria is pollinated by nectar-feeding native bees and wasps. The pollinia are patially separated from the viscidium by a stipe so that pollinia can be labelled with coloured histochemical stains without interfering with pollinarium removal. Pollen flow was monitored by following the movement of the coloured pollen in several populations of P. fimbria in Western Australia. Statistical analysis confirmed that pollen labelling did not interfere with pollinarium removal or subsequent pollination of the labelled flower. Fifty eight labelled pollinaria were removed by vectors from 16 test spikes, with a total of 125 flowers on 47 spikes receiving labelled pollen. An average of 2 flowers received pollen for every pollinium removed but up to 6 flowers received pollen from a single collinium. No significant differences between mean vector flights and pollen flow distances were detected. On average, geitonogamous transfers only accounted for 22% of all pollinations. This is a simple and inexpensive technique for the direct labelling of pollen with minimal disruption to the pollination system and may have applications in other plant families. 相似文献
9.
D. J. Senior P. P. Mayers D. Miller R. Sutcliffe L. Tan J. N. Saddler 《Biotechnology letters》1988,10(12):907-912
Summary The specificity of action of a cellulase-free xylanase preparation on pulp fibers was revealed by the composition of the solubilized products after enzyme treatment. The neutral carbohydrates released by the treatment of two hardwood kraft pulps were composed exclusively of xylooligomers. A similar treatment of Solka Floc showed no detrimental effect on the degree of polymerization of the cellulose fibers, as determined by size exclusion chromatographic analysis. 相似文献
10.
Rod W. Fry Alan R. Morton Peter Garcia-Webb G P M Crawford David Keast 《European journal of applied physiology and occupational physiology》1992,64(4):335-344
Five subjects undertook 10 days of twice daily interval training sessions on a treadmill followed by 5 days of active recovery. On days 1, 6, 11, and 16 the subjects were required to undertake a test of submaximal and maximal work capacity on a treadmill combined with a performance test consisting of a run to exhaustion with the treadmill set at 18 km.h-1 and 1% gradient. Also on these days a pre-exercise blood sample was collected and analysed for a range of haematological, biochemical and immunological parameters. The subjects experienced a significant fall in performance on day 11 which had returned to pretraining levels on day 16. Serum ferritin concentrations were depressed significantly from pretraining concentrations at the conclusion of the recovery period while the expression of lymphocyte activation antigens (CD25+ and HLA-DR+) was increased both after the training phase and the recovery phase. The number of CD56+ cells in the peripheral circulation was depressed at the conclusion of the recovery period. Several parameters previously reported to change in association with overload training failing to reflect the decrease in performance experienced by subjects in this study, suggesting that overtraining may best be diagnosed through a multifactorial approach to the recognition of symptoms. The most important factor to consider may be a decrease in the level of performance following a regeneration period. The magnitude of this decreased performance necessary for the diagnosis of overtraining and the nature of an "appropriate" regeneration period are, however, difficult to define and may vary depending upon the training background of the subjects and the nature of the preceding training. It may or may not be associated with biochemical, haematological, physiological and immunological indicators. Individual cases may present a different range of symptoms and diagnosis of overtraining should not be excluded based on the failure of blood parameters to demonstrate variation. However, blood parameters may be useful to identify possible aetiology in each separate case report of over-training. An outstanding factor to emerge from this study was the difficulty associated with an objective diagnosis of overtraining and this is a possible reason why there have been new accounts of overtraining research in the literature. 相似文献