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Oenothera hookeri L. pollen germination and pollen tube growth proceed in very similar ways in the pistil and in vitro. A characteristic feature of pollen grain germination is the emergence of one or more pollen tubes from 1, 2 or 3 colpi at the same time. The second specific event is the different way pollen tubes branch during their growth. The present study compares germination and pollen tube growth in fresh and frozen pollen grains. Pollen grain viability was estimated by fluorescein diacetate staining and tested by germination on medium. The localization of nuclear and plastid DNA was detected after DAPI staining. Sperm cell and vegetative nucleus positions were observed in only one of the pollen tube branches and pollen tubes germinating from the same pollen grain. The vegetative nucleus was weakly stained and its fluorescence was dim. The nuclei of sperm cells were very well seen and were found at different distances from the pollen tube tip. After a period of incubation the pollen tube containing sperm cells was always longer than other tubes or branches germinating from the same pollen grain. In some tubes the sperm cell nuclei seemed to change position from one branch to another. Sperm cells probably can move within the pollen tube growing in the ovary to the branch closest to the embryo sac.
The problem of the lack of offspring is a phenomenon concerning approximately 15% of married couples in Poland. Infertility is defi ned as inability to conceive after a year of sexual intercourses without the use of contraceptives. In half of the cases the causative factor is the male. Males are exposed to the effect of various environmental factors, which may decrease their reproductive capabilities. A decrease in male fertility is a phenomenon which occurs within years, which may suggest that one of the reasons for the decrease in semen parameters is the effect of the development of techniques in the surrounding environment. A hazardous effect on male fertility may be manifested by a decrease in the amount of sperm cells, disorders in their mobility, as well as structure. The causative agents may be chemical substances, ionizing radiation, stress, as well as electromagnetic waves. The objective of the study was the determination of the effect of the usage of cellular phones on the fertility of males subjected to marital infertility therapy. The following groups were selected from among 304 males covered by the study: Group A: 99 patients who did not use mobile phones, Group B: 157 males who have used GSM equipment sporadically for the period of 1-2 years, and Group C: 48 people who have been regularly using mobile phone for more than 2 years. In the analysis of the effect of GSM equipment on the semen it was noted that an increase in the percentage of sperm cells of abnormal morphology is associated with the duration of exposure to the waves emitted by the GSM phone. It was also confi rmed that a decrease in the percentage of sperm cells in vital progressing motility in the semen is correlated with the frequency of using mobile phones.
One recent advance in plant embryology is the experimental manipulation of various reproductive cells and their protoplasts under in vitro conditions. These experimental means may be helpful for understanding the developmental biology of sexual plant reproduction, on one hand, and developing novel methods in biotechnology, on the other. This article reviews a series of our works in this field. The article includes manipulation of pollen protoplasts, de-exined pollen, male gametoplasts and female gametoplasts. Each section starts with isolation of the cells/protoplasts and is followed by further manipulations such as culture, fusion, gene transfer, and also some cell biology studies based on and related to these manipulations.
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