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21.
Hydrophobins are small (length, about 100 +/- 25 amino acids), cysteine-rich, hydrophobic proteins that are present in large amounts in fungal cell walls, where they form part of the outermost layer (rodlet layer); sometimes, they can also be secreted into the medium. Different hydrophobins are associated with different developmental stages of a fungus, and their biological functions include protection of the hyphae against desiccation and attack by either bacterial or fungal parasites, hyphal adherence, and the lowering of surface tension of the culture medium to permit aerial growth of the hyphae. We identified and isolated a hydrophobin (fruit body hydrophobin 1 [Fbh1]) present in fruit bodies but absent in both monokaryotic and dikaryotic mycelia of the edible mushroom Pleurotus ostreatus. In order to study the temporal and spatial expression of the fbh1 gene, we determined the N-terminal amino acid sequence of Fbh1. We also synthesized and cloned the double-stranded cDNA corresponding to the full-length mRNA of Fbh1 to use it as a probe in both Northern blot and in situ hybridization experiments. Fbh1 mRNA is detectable in specific parts of the fruit body, and it is absent in other developmental stages.  相似文献   
22.
“Half Fat Margarine” and the New Margarine Legislation The new margarine law dated 28th May 1974 ammending the previous legislation legally permits the sale of a low calory spread on vegetable fat basis (“Half Fat Margarine”) in the Federal Republic of Germany. This law also provides a new definition of margarine, in addition to clauses that are applicable to half fat margarine. The regulations of the new legislation are explained. Moreover, the official regulations of various countries are given, in which the so called “low fat spreads” are already in market. Furthermore, another regulation concerning similar products on milk fat basis, which came into force almost simultaneously, is discussed.  相似文献   
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Fluorescence in situ hybridization (FISH) is a powerful tool for detection of numerical and structural chromosomal aberrations. We have compared conventional banding techniques and FISH for the detection of monosomy 7 (-7) and trisomy 8 (+8) in 89 patients with myeloid malignancies. Of these patients, 21 had -7, 30 had +8, four had both, and 34 had no aberrations or aberrations other than -7 or +8 as assessed by banding techniques. Sequential samples were available in 23 patients. Alphoid DNA probes specific for chromosomes no. 7 and 8 were used for FISH. As controls, 10 normal bone marrow (BM) samples were hybridized with the chromosomes no. 7 and 8 probes, and in addition all tumor samples were hybridized with a chromosome no. 1 specific probe. The cut-off value for -7 was 18% one-spot cells, and for +8 was 3% three-spot cells. FISH analysis of 44 samples with -7 or +8, and at least 10 metaphases evaluated, showed that the proportions of aberrant metaphase cells mirrored the interphase clone sizes. Most samples with nonclonal metaphase aberrations, including those with only a few metaphases, had increased numbers of aberrant interphase cells: 20% to 80% for -7, and 3% to 43% for +8. Interphase cytogenetics of the 34 samples without -7 or +8 did not show significant cell populations with -7 or +8. In four patients, -7 or +8 could not be confirmed by FISH due to additional structural aberrations, marker chromosomes, or wrongly interpreted banding results. As FISH will be used more and more in cytogenetic diagnosis, clinical follow-up, and therapy monitoring, it will be necessary to standardize FISH procedures and supplement the Standing Committee on Human Cytogenetic Nomenclature (ISCN) definitions of a clone with criteria specifically for in situ hybridization.  相似文献   
25.
A characteristic EPR spectrum is observed from Photosystem I (PS I) particles that are illuminated under reducing conditions. This signal is thought to arise from the secondary electron acceptor of PS I, A1. This EPR spectrum, along with data from other spectroscopic methods, has been taken as evidence that A1 is phylloquinone. In the work reported here, we have used a methionine auxotroph of Anabaena to deuterate specifically the 2-methyl group on the phylloquinone ring. Mass spectrometry of the isolated quinone shows 65% yield in the labeling procedure. The photoaccumulated A1 EPR spectra in protonated and deuterium-labeled cells are indistinguishable, from which we conclude that the photoaccumulated radical is not phylloquinone.  相似文献   
26.
Summary The first part of this survey paper is devoted to derive under rather weak conditions, which don't guarantee contraction, a number of important existency and convergency results in Markov decision theory. In the second part of the paper conditions that guarantee that the contraction mapping approach can be used are analysed. These conditions are rather weak and allow for unbounded rewards. The generation of successive approximation methods for solving Markov decision processes by using action depending stopping times is described at the end of the paper.
Zusammenfassung Im ersten Teil dieser Übersichtsarbeit werden unter schwachen Voraussetzungen, die keine Kontraktion garantieren, eine Reihe wichtiger Existenz- und Konvergenzaussagen für Markoffsche Entscheidungs-prozesse gewonnen. Im zweiten Teil der Arbeit werden Bedingungen untersucht, die einen Zugang mit Hilfe kontrahierender Abbildungen erlauben. Diese Bedingungen sind recht schwach, insbesondere sind unbeschränkte Erträge zugelassen. Am Ende der Arbeit wird beschrieben, wie man mit Hilfe aktionsabhängiger Stopzeiten verschiedene Verfahren der sukzessiven Approximation zur Lösung Markoffscher Entscheidungsprozesse gewinnen kann.
  相似文献   
27.
Analytical Characterisation of Palm Oil Fractions by HPLC of Triglycerides The increasing importance of palm oils and palm oil fractions in international trade makes it necessary to develop analytical criteria for the characterisation of these products. One problem is the correct identification of palm oleins, which are often difficult to distinguish from palm oils. These products frequently exhibit similar fatty acid by GLC and similar iodine values. The correct identification of palm stearins by GLC is comparatively more easy. Palm oleins and palm oils can be characterized by HPLC using conditions that permit not only the separation of triolein from less unsaturated triglycerides of the same carbon number, but also, at the same time, a separation of tripalmitin from triglycerides containing oleic acid. By establishing the peak area ratios for a number of selected triglycerides a clear differentiation between palm oils and palm oleins, as well as various other palm oil fractions and their mixtures is obtained.  相似文献   
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A method of enrichment for immature myeloid cells from normal human bone marrow has been described. The method is based on 4 consecutive steps: 1. Density cut centrifugation. After centrifugation all cells above the pellet were collected. This suspension contained 93% of the originally present myeloblasts and promyelocytes. The majority of normoblasts and granulocytes was found in the pellet. 2. Nylon wool filtration. This procedure was performed to remove the majority (87%) of the monocytes. Recovery of myeloblasts and promyelocytes after filtration was 74%. 3. Centrifugation on a continuous density gradient. This procedure resulted in an additional purification of the myeloblasts and promyelocytes within a specific fraction. By centrifugation the concentration of myeloblasts and promyelocytes was increased from 19% to 38%. 4. Velocity sedimentation at 1 g. This technique produced a 82% pure immature myeloid cell suspension, comprising 57% myeloblasts and promyelocytes. All figures are the mean of 10 experiments.  相似文献   
30.
A study of Mg‐based bulk metallic glasses (BMGs) as biodegradable bone implants is presented. The implantation site can affect performance, so the BMGs were evaluated in vivo in rat femurs using µ‐CT scans at various times for more than 90 days. Estimates of H2 evolution correlate well with previous in vitro studies and bone–implant contact is similar to that for Ti pins. One potential drawback of Mg‐based BMGs in this application is embrittlement due to structural relaxation. Here, relaxation at 20 and 37 °C is examined, and an increase in the characteristic relaxation time, from 10 to 30 days at 20 °C, is observed as Zn increases from 29 to 32 at.%, correlating with dramatically reduced hydrogen evolution.  相似文献   
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