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591.
592.
Kizilgeci Ferhat Bayhan Bora Türkoğlu Aras Haliloglu Kamil Yildirim Mehmet 《Molecular biology reports》2022,49(9):8567-8574
Molecular Biology Reports - Turkey is not only a center of origin for wheat, but also contains wild forms of various cereals. Turkey, located in the Fertile Crescent, has conserved its genetic... 相似文献
593.
Martin Konvicka Kamil Zimmermann Martina Klimova Vladimir Hula Zdenek Fric 《Population Ecology》2012,54(1):91-101
A pertinent question in animal population ecology is the relationship between population abundance, density, and mobility.
Two extreme ways to reach sufficient abundance for long-term persistence are to inhabit restricted locations at high densities,
or large areas in low densities. The former case predicts low individual mobility, whereas the later predicts high one. This
assumption is rarely tested using across-species comparisons, due to scarcity of data on both mobility and population sizes
for multiple species. We used data on dispersal and local population densities of six butterfly species gained by mark-recapture,
and data on their (relative) regional abundance obtained by walking transects in a landscape surrounding the mark-recapture
sites. We correlated both local density and regional abundance against slopes of the inverse power function, appropriate for
describing the shape of dispersal kernel. Local densities correlated negatively with the dispersal kernel slopes both when
sexes were treated as independent data points and if treated together. For regional abundance, the correlation was also negative
but only marginally significant. Our results corroborate the notion that a trade-off exists between living in dense populations
and having poor dispersal, and vice versa. We link this observation to resource use by individual species, and distribution
of such resources as host plants in the study landscape. 相似文献
594.
The viral glycoproteins that decorate enveloped viruses play crucial roles in cell entry and in large part dictate the spectrum of cell types that a virus can infect. The identification in human cytomegalovirus (HCMV) of a viral endoplasmic reticulum (ER)-resident glycoprotein that regulates the composition of alternative viral envelope glycoprotein complexes raises the intriguing possibility that certain viruses might actively regulate the tropism of progeny virions to improve their fitness or to navigate through the host. 相似文献
595.
The structure of diverticula of the female gonads was analyzed in two scorpions from the family Scorpionidae by means of standard microscopic techniques (light microscopy, histochemistry, transmission electron microscopy). In scorpions, the female gonad, termed the ovariuterus, participates in two consecutive processes: oogenesis and embryogenesis. In sexually reproducing scorpions, the ovariuterus is also involved in fertilization. Both scorpions under study reproduce sexually. They also represent the katoikogenic type of development, which means that oogenesis, fertilization, and embryogenesis take place in the diverticula, which are sac-like outpocketings of the ovariuterine tubules. Formation of a lumen in the diverticulum is indispensable for sperm entry to enable fertilization and subsequent embryogenesis. The aim of the study was to test our hypothesis that the diverticulum lumen forms due to the engagement of the centrally located stalk cells. In this report, we show that in two species of katoikogenic scorpions, at the final stages of oogenesis, the cytoplasm of the stalk cells contains secretory organelles. In the stages preceding fertilization, secretory activity of the stalk cells and fragmentation of their apical parts lead to formation of the diverticulum lumen by a process similar to “cord hollowing” that commonly occurs for lumen formation in other morphogenesis model systems. 相似文献
596.
Kamil Rybníček James Dickson Eliška Rybníčková 《Vegetation History and Archaeobotany》1998,7(3):155-165
The paper presents and evaluates the results of macroscopic and pollen analyses of a buried organic layer at the confluence of the Svitava and Svratka rivers on the southern margin of the Brno City, southern Moravia, Czech Republic. The layer was covered with about 4 m of flood-loams and dates to ca. A.D. 1100. Remains of nearly 100 vascular plants and about 40 mosses contribute to the knowledge of the medieval flora, vegetation and environment in the vicinity of Brno as continuous settlement began in the city area and as the upstream landscapes were colonised. 相似文献