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31.
An-Fei Hsu Dorothy Brower Ronald B. Etskovitz Peter K. Chen Donald D. Bills 《Phytochemistry》1983,22(7):1665-1669
A radioimmunoassay (RIA) procedure for the determination of pmol quantitites of morphine in capsule samples of Papaver somniferum was developed. An antiserum developed against a conjugate of morphine-3-hemisuccinate-BSA was relatively specific for morphine and possessed moderated cross-reactivity with codeine and mild cross-reactivity with thebaine, but none with narceine, papaverine, or noscapine. The standard curve was linear over a range of 0.01–0.20 ng. This assay allows for the rapid, sensitive and precise determination of morphine in unpurified aqueous extracts of capsule samples. The amounts of morphine in the aqueous extracts determined by radioimmunoassay were validated by high performance liquid chromatography (HPLC). The two methods show a high correlation coefficient (r = 0.98) with no significant difference in determinations of morphine content by RIA and HPLC. 相似文献
32.
Peeter Kangur 《Hydrobiologia》1996,338(1-3):173-177
The population of bream in L. Peipsi was studied with respect to age, growth rate, condition factor (according to Fulton) and length-weight relationship in 1994. That autumn the bream population in L. Peipsi consisted of fishes aged from 0+ to 15+. During the first year bream reached an average body length of 7.9 cm (the commercial legal size (30 cm) was usually attained by the end of the 5th–6th year. The condition of bream in this lake was above the average of Estonian lakes. The relatively good growth rate and condition of bream in the lake indicates that the waterbody is appropriate for this fish. 相似文献
33.
J. Des Forts 《International Journal of Anthropology》1996,11(2-4):123-136
For millenaria, maternal mortality has been considered as a fatality inherent to women's condition. Thanks to the progress of the obstetric technology, the world M.M.R. fell from 2.000 to 400 per 100.000 births during the past 150 years. At the same time women's condition improved chiefly because of a better level of education. Is there any relationship between them: the decrease of Maternal Mortality and the amelioration of women's general status? Or, in other words, can the decrease of Maternal Mortality Rate be considered as an “indicator” of the situation of women? After a historical review of the importance of the maternal mortality drama as it occured in older times before the “obstetric era”, which began with the improvement of the obstetric technology, this paper will present the actual situation of maternal mortality in relation with the obstetric coverage, the female literacy level and some other socio-economic variables, and in relation with the Gross National Product (G.N.P.) as an indicator of governmental interest in the specific female problems of giving-life. 相似文献
34.
Abstract: Possible effects on the physiological activity and culturability of soil microorganisms by different soil dispersion procedures, and effects on activity caused by extracting bacteria from soil, were investigated. There was no apparent difference in cfu's with dispersion of a silty loam soil and a loamy sand soil with pyrophosphate as compared to dispersion in NaCl. Substrate-induced respiration was reduced in the silty loam soil, and methanol oxidation was reduced in the loamy sand soil with dispersion in pyrophosphate, and the soil pH was irreversibly increased by the treatment. Extracted bacterial fractions had lower numbers of culturable cells as percentage of the total number of bacteria in each fraction, lower respiration rates and no methanol oxidation activity as compared to the soil slurry both before and after extraction. The physiological activity was apparently not affected by the number of cells extracted. This indicates that the increased extraction rate of indigenous soil bacteria obtained by effective disruption of aggregates and detachment of cells from surfaces, only results in increased extraction of cells that have been physiologically changed as a result of the extraction process. 相似文献
35.
Microspore culture is a very important and useful tool in plant breeding for haploid production and has been developed for many years.Brassica campestris (Brassica rapa L. ssp.oleifera) is an important oilseed crop, but it is relatively recalcitrant in tissue culture including microspore culture. The microspore culture in our laboratory is based on the Canadian protocol. Thirty genotypes ofB. campestris were included in this study; twenty produced embryos. The highest yield was 5930 embryos per 100 buds from Canadian genotype Cv-2, this result was one of the best that had been reported in microspore culture inB. campestris. The buds measuring 2.0 mm to 3.9 mm in length responded best to produce embryos, the optimum timing for microspore culture was confirmed to be during the mid-late to very-late uninucleate stage. The buds could be removed from either the main raceme or lateral racemes. Activated charcoal (150 mg l-1) was added to the liquid NLN medium, it promoted embryogenesis significantly; embryo development was faster and the embryo yield was significantly higher than those cultures without activated charcoal. The donor plant condition was considered an important factor influencing embryogenesis; older donor plants (older than five weeks) and a cold treatment are recommended. 相似文献
36.
Kristel Eggermont Inge J. Goderis Willem F. Broekaert 《Plant Molecular Biology Reporter》1996,14(3):273-279
We describe here a reliable high-throughput method for extraction of RNA from fresh or frozen plant tissue that obviates laborious
and time-consuming homogenisation by mortar and pestle. The method is based on homogenisation by high-speed reciprocal shaking
in presence of a mixture of inexpensive abrasive materials; i.e., quartz sand and glass beads. After homogenisation, the method
follows a standard procedure for RNA extraction by phenol/LiCl. Yield and quality of RNA obtained by homogenisation with the
sand/glass bead mix are identical to those obtained by mortar and pestle. 相似文献
37.
The tiny seeds of parasitic weeds of the genusOrobanche can be identified by using RAPD markers. A simple procedure for DNA extraction from single seeds, 10 μg each, followed by
RAPD-PCR and using specific DNA markers, leads to species identification. Seeds of five different species could be identified
using this method. 相似文献
38.
Summary Pyrolysis mass spectrometry (PyMS) was used to produce biochemical fingerprints from replicate frozen cell cultures of mouse macrophage hybridoma 2C11-12, human leukaemia K562, baby hamster kidney BHK 21/C13, and mouse tumour BW-O, and a fresh culture of Chinese hamster ovary CHO cells. The dimensionality of these data was reduced by the unsupervised feature extraction pattern recognition technique of auto-associative neural networks. The clusters observed were compared with the groups obtained from the more conventional statistical approaches of hierarchical cluster analysis. It was observed that frozen and fresh cell line cultures gave very different pyrolysis mass spectra. When only the frozen animal cells were analysed by PyMS, auto-associative artificial neural networks (ANNs) were employed to discriminate between them successfully. Furthermore, very similar classifications were observed when the same spectral data were analysed using hierarchical cluster analysis. We demonstrate that this approach can detect the contamination of cell lines with low numbers of bacteria and fungi; this approach could plausibly be extended for the rapid detection of mycoplasma infection in animal cell lines. The major advantages that PyMS offers over more conventional methods used to type cell lines and to screen for microbial infection, such as DNA fingerprinting, are its speed, sensitivity and the ability to analyse hundreds of samples per day. We conclude that the combination of PyMS and ANNs can provide a rapid and accurate discriminatory technique for the authentication of animal cell line cultures. 相似文献
39.
屎克螂适宜的繁殖条件初步研究 总被引:2,自引:0,他引:2
1991—1994年对屎克螂适宜的繁殖条件研究结果:1.土层40cm和60cm的平均温度分别为15.92±6.34℃和15.89±6.08℃;平均土壤含水量分别为26.70±3.74%和23.72±1.88%,使各虫态处于一个几乎恒温恒湿的条件,有利于生长发育与越冬,2.土壤含水量17%、20%、22%、26%和29%,其产卵最多的深度分别在65─70cm,75─80cm,65─80cm,65—80cm和35—50cm,分别占产卵总数的34.16%、42.42%、68.42%、55.40%和90.56%。3.不同土壤的产卵深度,沙壤土以土下45—50cm处最多,占产卵总数的34.78%;沙土以65—85cm最多,占产卵总数的86.67%;粘土以45—60cm最多,占产卵总数的51.11%。 相似文献
40.
在自生异养条件下,旋扭山绿豆根瘤菌MXDI6菌株的氢酶诱导表达受气相、pH值、镍等因子影响:氢酶表达的最适氧浓度为4%,最适氢浓度为15%,二氧化碳没有明显影响;氢酶表达的pH值以5.0—6.0为宜;0.5μmol/LNiCl2明显促进吸氢活性,但镍浓度大于1μmol/L则抑制吸氢活性. 相似文献