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981.
982.
983.
Plant Ecology - There is increasing evidence that climate change and nutrient fluctuations can affect the invasion of alien plants. However, most studies have been performed in pairwise experiments... 相似文献
984.
The results of experimental studies on the contribution of zoogenic debris to transformation of soil properties in the southern taiga subzone of Central Siberia are analyzed. They show that water-soluble carbon outflow from the forest litter increases by 21–26% upon a Siberian moth invasion, with this value decreasing to 14% one year later. The burning of forest in an area completely defoliated by the pest leads to changes in the stock, fractional composition, actual acidity, and ash element contents of the litter. The litter-dwelling invertebrate assemblage is almost completely destroyed by fire and begins to recover only after two years. 相似文献
985.
986.
Yixin Yu 《Insect Science》1997,4(1):56-58
Abstract Male and female adults of Leptoconops (Leptocmps) longicauda new species are described from material colleted from Wudang Mountain, Hubei Province, China. 相似文献
987.
Yan-yiu Yu Chelsea Bahney Diane Hu Ralph S. Marcucio Theodore Miclau III 《Journal of visualized experiments : JoVE》2012,(62)
Assessing modes of skeletal repair is essential for developing therapies to be used clinically to treat fractures. Mechanical stability plays a large role in healing of bone injuries. In the worst-case scenario mechanical instability can lead to delayed or non-union in humans. However, motion can also stimulate the healing process. In fractures that have motion cartilage forms to stabilize the fracture bone ends, and this cartilage is gradually replaced by bone through recapitulation of the developmental process of endochondral ossification. In contrast, if a bone fracture is rigidly stabilized bone forms directly via intramembranous ossification. Clinically, both endochondral and intramembranous ossification occur simultaneously. To effectively replicate this process investigators insert a pin into the medullary canal of the fractured bone as described by Bonnarens4. This experimental method provides excellent lateral stability while allowing rotational instability to persist. However, our understanding of the mechanisms that regulate these two distinct processes can also be enhanced by experimentally isolating each of these processes. We have developed a stabilization protocol that provides rotational and lateral stabilization. In this model, intramembranous ossification is the only mode of healing that is observed, and healing parameters can be compared among different strains of genetically modified mice 5-7, after application of bioactive molecules 8,9, after altering physiological parameters of healing 10, after modifying the amount or time of stabilization 11, after distraction osteogenesis 12, after creation of a non-union 13, or after creation of a critical sized defect. Here, we illustrate how to apply the modified Ilizarov fixators for studying tibial fracture healing and distraction osteogenesis in mice. 相似文献
988.
V. A. Efimov A. A. Buryakova N. N. Polushin I. Y. Dubey O. G. Chakhmakhcheva Yu. A. Ovchinnikov 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):279-282
Abstract An effective method for the synthesis of oligonucleotides by the phosphotriester approach has been developed. It is based on the use of phosphate protecting groups enabling O-nucleophilic intramolecular catalysis. 相似文献
989.
990.
The results of studies on the axial skeleton of the common toad (a model species) have been used to analyze factual limitations of individual variation. The results show that the states of the studied characters do not freely combine with each other but are subject to certain morphogenetic limitations. The causes of most these limitations have been revealed during the study. Classification of the main factors limiting individual variation in the course of development is presented. 相似文献