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421.
Witold Komocki 《Cell and tissue research》1939,29(2):201-213
Ohne Zusammenfassung 相似文献
422.
423.
U-snRNA genes,U-snRNAs and U-snRNPs of higher plants 总被引:2,自引:0,他引:2
Witold Filipowicz Tamas Kiss Chris Marshallsay Franz Waibel 《Molecular biology reports》1990,14(2-3):125-129
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425.
In the Scottish Highlands, Scots pine is at the north-western extreme of its wide natural distribution. Here, the remaining native populations are patchily distributed in highly variable environments, from the more continental, drier eastern Highlands to the milder, wetter Atlantic Ocean coast. As these pinewoods are the remnants of a naturally established forest, they form a valuable system for analysis of genetic and adaptive variation in heterogeneous environments. Using samples from across the Scottish population, we analysed data from nuclear and mitochondrial genes to assess patterns of within and between population genetic variation. Within population diversity levels were high, and significant genetic differentiation among pairs of Scottish populations at relatively small spatial scales was present at several nuclear loci. At these loci, no differentiation had been found among continental populations, even those separated by large geographic distances. Overall, no clear clustering of Scottish samples was found in population structure analysis suggesting that geographically distant populations with high intra-population nucleotide diversity are not strongly isolated or diverged from each other. Scottish populations lacked a mitotype that is widespread in eastern and north-eastern Europe, indicating that pines from that area may not have participated in the most recent colonisation of the British Isles. 相似文献
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427.
Third-instar larvae of the scarabaeid Sericesthis geminata were stimulated to bite and feed on filter paper by a number of sugars, amino acids and lipids. The degree of stimulation generally increased with increasing concentration, but high concentrations of fructose and amino acid had inhibitory effects. Sterols were non-stimulating at low concentrations and acted as feeding deterrents at high ones.
Zusammenfassung In einer Reihe von einfachen Wahlkammerversuchen wurde das Verhalten der bodenbewohnenden Larven des Scarabaeiden Sericesthis geminata (Boisduval) gegenüber Zuckern, Aminosäuren und Lipiden geprüft. Die Versuchschemikalien wurden in verschiedenen Konzentrationen auf Filtrierpapier aufgetragen und die gefressenen Stellen ausgemessen.Jeder der drei Zucker Saccharose, Maltose und Glucose erhöhte die Nahrungsaufnahme. Die Disaccharide Saccharose und Maltose hatten einen größeren Effekt als Glucose. Bei diesen drei Zuckern war im allgemeinen bis zu einer Konzentration von 1.0 M ein zunehmender Effekt festzustellen. Fructose erhöhte die Nahrungsaufnahme nicht und hatte bei höheren Konzentrationen einen hemmenden Effekt. Die einzelnen Aminosäuren L-Isoleucin, L-Leucin und L-Alanin sowie eine Gruppe von sechs Aminosäuren erhöhten die Nahrungsaufnahme in einem begrenzten Konzentrationsbereich, hemmten aber die Nahrungsaufnahme bei hohen Konzentrationen. Die Wirkung der Gruppe von Aminosäuren zeigte, daß dabei der Effekt der verschiedenen Aminosäuren komplementär war. Freie Fettsäuren, Triglyceride und Phospholipoide erhöhten die Nahrungsaufnahme. Steroide hatten bis zu hohen Konzentrationen keinen wesentlichen Einfluß; bei hohen Konzentrationen wurde die Nahrungsaufnahme verringert.相似文献
428.
Anna Majewska Witold Lasek Mariola Kuczer Grażyna Młynarczyk 《International journal of peptide research and therapeutics》2016,22(2):255-261
Over the past two decades there has been intense study of compounds from vertebrates, microorganisms, plants, mushrooms, marine sponges, worms, etc. as well as insects in terms of their antiviral activity. Insects produce a variety of biologically active peptides. One of them is alloferon. The in vitro and in vivo experiments demonstrate that synthetic alloferon has an immunomodulatory properties. It was reported that alloferon and its analogues (alloferon I and II) have antimicrobial properties, as well. The aim of this study was to evaluate in vitro the effect of alloferon I and II, either alone or in combination with human lymphocytes, on human herpesvirus type 1 (HHV-1) McIntyre strain replication. On the base of results we can conclude that alloferon I and II inhibit the replication of HHV-1 McIntyre strain in HEp-2 cells. Enhanced antiviral activity was observed when infected cells were treated with alloferons and unstimulated or phytohemagglutinin PHA-stimulated lymphocytes simultaneously. After application of alloferons and PHA-stimulated lymphocytes to the HHV-1 infected HEp-2 culture, the mean HHV-1 titer reduction for alloferon and II, when used at the highest dose—400 µg/mL, were 3.69 and 3.27 log10/TCID50/mL, respectively. 相似文献
429.
A combined method for clearing soft tissues, staining cartilage and bone, and injecting the vascular system of small mammals was developed using Mus musculus (house mouse). Mammalian muscle tissue remains milky or even opaque after “clearing” by previous techniques due to the relatively high content of intramuscular fat. A method employing chloroform-ethanol successfully renders soft tissues of mammalian specimens translucent without damaging or bleeding color from the latex injected in the circulatory system. Resulting specimens yield an excellent view of the skeletal system and the injected vascular system without obstruction by opaque tissues or disruption by physical removal of connective tissue. 相似文献
430.
The concentrations of glycine and 6 other amino acids have been assayed in the CSF and plasma of the rat, and regional heterogeneity of CSF amino acid concentration has been found. Steady state flux rates into the cranial and spinal fluid compartments were determined during perfusion with amino acid free medium. The transfer of glycine from blood into both the cranial and spinal subarachnoid fluids was saturable with only several-fold elevations of plasma glycine. The results are discussed with regard to the putative neurotransmitter function of glycine in the spinal cord. 相似文献