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11.
P. Witzgall W. Sauter H.-R. Buser S. Rauscher H. Arn P. J. Charmillot Th. Wildbolz 《Entomologia Experimentalis et Applicata》1989,53(2):133-136
As shown by chemical analysis and field trapping, the sex pheromone of Grapholita lobarzewskii consists of a blend of (E)-8-dodecenyl acetate and (Z)-8-dodecenyl acetate. Maximum attractiveness was found at 80–95%. Dodecyl acetate and tetradecyl acetate, both present in the female gland, did not affect trap catch. G. lobarzewskii has recently gained importance as a pest of apple and plum, but has so far been referred to as Grapholita janthinana. The latter is attracted to the same two compounds, but in reversed portions (20% E).
Zusammenfassung Chemische Analysen und Feldversuche zeigen, dass das Sexualpheromon des Kleinen Fruchtwicklers, G. lobarzewskii aus (E)-8-Dodecenylacetat (Z8-12:Ac) und (Z)-8-Dodecenylacetat (Z8-12:Ac) besteht. Die grösste Lockwirkung wurde mit einem Gemisch der beiden Substanzen bei einem E-Anteil von 80–95% erzielt. Dodecylacetat (12:Ac) und Tetradecylacetat (14:Ac) wurden ebenfalls in den weiblichen Pheromondrüsen nachgewiesen, hatten aber im Freiland keinen Einfluss auf die Lockwirkung. G. lobarzewskii tritt seit einiger Zeit in der Schweiz als Schädling von Apfel und Zwetschge auf und ist an ihrem charakteristischem Frassgang leicht erkennbar. Die Art wurde bisher irrtümlich als G. janthinana bezeichnet. G. janthinana lebt auf Rosaceen, und wird vom gleichen Substanzpaar angelockt, allerdings bei umgekehrtem Mischungsverhältnis (20% E).相似文献
12.
Summary Fibrous components other than collagen fibrils in the reticular fiber of mouse lymph node were studied by electron microscopy. Bundles of microfibrils not associated by elastin and single microfibrils dispersed among collagen fibrils were present. The diameter of the microfibrils was 13.29±2.43 nm (n=100). Elastin-associated microfibrils occurred at the periphery of the reticular fiber. Elastin was enclosed by microfibrils, thus forming the elastic fiber, which was clearly demonstrated by tannic acid-uranyl acetate staining. In the reticular fiber of lymph nodes, the elastic fiber consisted of many more microfibrils and a small amount of elastin. These microfibrils, together with the collagen fibrils, may contribut to the various functions of the reticular fibers. 相似文献
13.
Summary Axillary bud expiants from South Pacific (Solomon Islands) taro, Colocasia esculenta var. esculenta cv. Akalomamale (Araceae) cultured on a modified Murashige-Skoog medium containing 1 mg NAA 1–1 and TE formed callus and produced multiple plantlets. Explants died if NAA was present at levels lower than 0.1 mg 1–1. BA was not required and may have been inhibitory. Plantlets developed faster and became larger following transfer to a hormone-free medium two weeks after the start of culture. Fully grown plants were established in a potting mix and are growing well in a greenhouse.Abbreviations BA
benzyladenine
- BM
basal medium
- Ca
Colocasia esculenta var. antiquorum
- Ce
Colocasia esculenta var. esculenta
- Ck
cytokinin(s)
- CW
coconut water
- HSMSM
half strength Murashige Skoog macroelements
- HSMS
half strength Murashige and Skoog medium
- IM
initial medium(ia)
- MS
Murashige and Skoog medium
- NAA
naphthaleneacetic acid
- SM
second medium
- TE
taro corm extract
- UCI
University of California, Irvine 相似文献
14.
Alan J. Slusarenko 《Plant Molecular Biology Reporter》1990,8(4):249-252
A procedure which avoids the use of phenol-chloroform and RNAase for the isolation of total DNA fromA. tumefaciens is described. Specific precipitation of protein by 2.5 M ammonium acetate is employed and much of the RNA is removed by an isopropanol
precipition step. The procedure yields easily restrictable, good quality DNA and is probably applicable to other Gramnegative
bacteria. 相似文献
15.
用酸浸提、酒精沉淀法,从桔皮中提取果胶,通过正交设计分析,获得最佳得率的工艺条件。即果胶浸提液的酸度为pH2,反应时间2小时。沉淀果胶的酒精浓度为50%,其得率是12.6%。 相似文献
16.
Jose L. Vega Vicki L. Holmberg Edgar C. Clausen James L. Gaddy 《Archives of microbiology》1988,151(1):65-70
Intrinsic growth and substrate uptake parameters were obtained for Peptostreptococcus productus, strain U-1, using carbon monoxide as the limiting substrate. A modified Monod model with substrate inhibition was used for modeling. In addition, a product yield of 0.25 mol acetate/mol CO and a cell yield of 0.034 g cells/g CO were obtained. While CO was found to be the primary substrate, P. productus is able to produce acetate from CO2 and H2, although this substrate could not sustain growth. Yeast extract was found to also be a growth substrate. A yield of 0.017 g cell/g yeast extract and a product yield of 0.14 g acetate/g yeast extract were obtained. In the presence of acetate, the maximum specific CO uptake rate was increased by 40% compared to the maximum without acetate present. Cell replication was inhibited at acetate concentrations of 30 g/l. Methionine was found to be an essential nutrient for growth and CO uptake by P. productus. A minimum amount of a complex medium such as yeast extract (0.01%) is, however, required. 相似文献
17.
Improved media for normal human muscle satellite cells: Serum-free clonal growth and enhanced growth with low serum 总被引:5,自引:0,他引:5
Richard G. Ham Judy A. St. Clair Cecelia Webster Helen M. Blau 《In vitro cellular & developmental biology. Plant》1988,24(8):833-844
Summary We have developed a serum-free medium for clonal growth of normal human muscle satellite cells (HMSC). It consists of an optimized
nutrient medium MCDB 120, plus a serum-free supplement, designated SF, that contains epidermal growth factor (EGF), insulin,
dexamethasone, bovine serum albumin, and fetuin. Fibroblast growth factor was needed with dialyzed fetal bovine serum (dFBS)
as the only other supplement, but in media containing SF, it was only slightly beneficial, and was omitted from the final
medium without significant loss. Clonal growth of HMSC in MCDB 120 plus SF is as good as with 15% serum and 0.5% chicken embryo
or bovine pituitary extract. However, growth is further improved by use of a doubly-supplemented (DS) medium containing both
SF and 5% dFBS. Clonal growth of HMSC in the DS medium far exceeds that in previous media with any amount of serum, and monolayer
growth is at least equal to that in conventional media with higher levels of serum. Cells grown in these media exhibit little
differentiation, even when grown to high densities. However, they retain the capacity for extensive fusion and synthesis of
increased creatine kinase when transferred to a serum-free differentiation-promoting medium, such as Dulbecco's modified Eagle's
medium plus insulin. All experiments were done with clonal cultures of HMSC to insure that observed growth responses were
always those of muscle cells.
This research was supported by a grant from the Muscular, Dystrophy Association.
Editor's statement This article describes the optimization of both the basal nutrient medium and growth factor requirements
for human muscle cells in vitro. This system is critical for studies of normal muscle cell and molecular biology, as well
as for understanding diseases of muscle such as Duchenne, Muscular Dystrophy. 相似文献
18.
19.
J. Van Den Ende 《Plant and Soil》1991,133(1):65-74
The products of activities of calcium and sulphate were calculated for solutions of 75 glasshouse soils. The majority of these products was found to be higher than the solubility product of gypsum, thus indicating that these soil solutions were possibly supersaturated. In another investigation, soil solutions were examined to determine whether such high activity products could be really attributed to supersaturation. By means of ultracentrifuging of solutions of glasshouse soils, it could be established that the solutions were practically free of sulphate-bearing colloidal particles. Some solutions contained calcium-bearing colloidal particles, but the quantities of calcium contained in these particles were too small to substantially influence the calcium activity. Addition of gypsum crystals to soil solutions led to crystallization of so much calcium and sulphate that the products of the activities of calcium and sulphate dropped from values that can be listed as high to values approaching the solubility product of gypsum. The results obtained demonstrate the occurrence of supersaturation of soil solutions with respect to gypsum. It is further postulated that the presence of humic substances in the soil solution is responsible for this supersaturation. The possible occurrence of supersaturation with respect to gypsum in soils other than glasshouse soils is discussed. 相似文献
20.
Piero Pollesello Renato Toffanin Erminio Murano Roberto Rizzo Sergio Paoletti Bjarne J. Kvam 《Journal of applied phycology》1992,4(2):149-155
Lipid extracts of the red algaGracilaria longa were studied by1H- and13C-NMR spectroscopy. Peaks in the13C-NMR spectra attributable to sterols, chlorophylls and carotenoids allowed free and acylated cholesterol, chlorophylla and lutein to be identified as the most abundant components of these classes. A content of 0.5 ± 0.1 μmoles of total cholesterol/g
wet alga was estimated from the1H-NMR spectrum, which also allowed the determination of the phosphatidylcholine/total lipid molar ratio (9.5 ± 0.5%). The13C-NMR spectroscopic experiments provided information on the position of the double bonds on the fatty acid residues. A comparison
between NMR spectra of lipid extracts obtained for wet and dried alga showed that the alga undergoes both a dramatic peroxidation
and some glycolipid degradation during the drying process. 相似文献