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1.
A capping process of epidermal growth factor receptors (EGF-Rs) was used for the study of the relation between the receptors and the actin-binding proteins (spectrin, vinculin, annexin I) that may be involved in EGF-R-cytoskeleton interaction. In intact, adherent A431 cells, EGF-Rs were diffusively distributed on the cell surface. Spectrin, vinculin, and annexin I were located beneath the plasma membrane. An abundance of EGF-Rs as well as submembrane proteins was observed in regions of membrane ruffles and cell-cell contacts. Annexin I was localized also in cytoplasm being attached to filamentous structures surrounding the nucleus and extending to the cell periphery. Under polyvalent ligand treatment, EGF-Rs of adherent cells were aggregated on one side of the cell. Spectrin, vinculin, and annexin I dislocated together with EGF-Rs and were concentrated under plasma membrane at regions where cap formation took place. In suspended A431 cells only spectrin was located under the plasma membrane whereas annexin I and vinculin were diffusively distributed through the cells. During cap formation only spectrin was colocalized with EGF-Rs. The results confirmed the major role of spectrin as a receptor-microfilament linking protein.  相似文献   
2.
Russian Journal of Genetics - The ITS1–5.8S rDNA–ITS2 sequence of the 35S rRNA genes of 16 species of feather grasses and 2 species of false needlegrasses of the flora of the Altai...  相似文献   
3.
The effects of cage fish farming on physico-chemical and bacteriological water quality in Lake Volta, Ghana, were investigated in 2013–2014. Farmed and unfarmed (control) areas of the lake were selected for monitoring. Nutrients, temperature, dissolved oxygen, conductivity, turbidity, pH, total coliforms, Pseudomonas and Vibrio spp. in the water were monitored monthly. Analyses of the water samples were carried out according to standard procedures. Physico-chemical quality of the water in both farm and control sites were within ranges typical of minimally impacted water and did not vary significantly between the two contrasting sites. The bacteriological analysis, however, revealed contamination of the lake water by fish farming. The bacterial counts at the farmed sites were significantly higher (p < 0.05) than those of the control sites, with figures at the farmed sites ranging from 132 to 1 708 cfu 100 ml?1 for total coliforms, 514 to 5 170 cfu 100 ml?1 Pseudomonas spp. and 14 to 516 cfu 100 ml?1 for Vibrio spp. The results suggested that cage fish farming has increased bacterial loads in the lake water, but has had minimal impact on its physico-chemical quality.  相似文献   
4.
Stipa shanxiensis, a cryptic species within Stipa grandis that originated from central and western China, is described based on morphological, genomic, and ecological data from field and common garden experiments. Stipa shanxiensis morphologically resembles S. grandis, although phylogenetically it is closely related to the less morphologically similar Stipa baicalensis and Stipa krylovii. Of the eight significant morphological differences between S. shanxiensis and S. grandis, the two, cauline ligules longer than 2 cm with a filiform apex, and hairs shorter than 0.2 mm on the adaxial surface of the cauline uppermost leaves can be used to distinguish the species. Results from a common garden experiment verified that the two diagnostic characteristics were relatively stable and less morphologically plastic in response to environmental variation. Furthermore, a significant ecological divergence was found between S. shanxiensis and S. grandis, such that the former preferred warmer and more humid climates, and their predicted distribution was generally separated. Taken together, our results highlight that the integrative taxonomic approach was valuable for recognizing a new cryptic species in Stipa. In particular, we find that common garden experiments involving the effects of growth stage and characteristic position helped to morphologically diagnose cryptic species. These findings may also facilitate our understandings of ecological adaption and phenotypic plasticity in response to environmental change.  相似文献   
5.
This paper presents a summary of reported cases of Serious Adverse Events (SAEs) following treatment with Mectizan® (ivermectin, Merck, Sharpe &; Dohme) in onchocerciasis mass treatment programs from January 1, 1989 to December 31, 2001 through a passive surveillance system. A total of 207 SAE cases were reported out of approximately 165 million reported treatments delivered during the period under review, giving rise to a cumulative incidence of 1 reported SAE per 800,000 reported treatments. The mean age was 40 years and 70% of the cases were males. The mean time between ivermectin intake and onset of illness was 1 day. For 57% of the cases (n = 118), that was their first exposure to ivermectin. The majority of cases were reported from Cameroon (n = 176; 85%) with peaks in the incidence of SAE reporting in 1989–1991 and 1994–1995 when the program expanded to ivermectin-naïve populations. Fifty-five percent of the cases from Cameroon (i.e. 97 out of 176 cases) were encephalopathic and were reported from the central-southern region of the country; two-thirds of these cases were 'probable' or 'possible' cases of Loa loa encephalopathy temporally related to ivermectin treatment. Reporting bias may explain some but not all of the differences in SAE reporting between the 34 onchocerciasis-endemic countries that have, or have had, mass treatment programs. Further research is needed to understand the apparent clustering of encephalopathy cases in central-southern Cameroon since L. loa infection alone probably does not explain the increased incidence of this type of SAE from this region.  相似文献   
6.
A search of transthyretin (TTR) gene mutations was performed in patients with cardiomyopathies from St. Petersburg. Mutations H90N, V30M and deletion (del9) of nucleotides GACTTCTCC in position 6776 from the start codon of the TTR gene (in position 98782 according to reference sequence AC079096 (NCBI) was found. The H90N mutation in the third exon of TTR gene was detected in a son of a cardiomyopathy patient and in his mother, which lacked any clinical manifestations. Mutation V30M in exon 2 of TTR gene was found in heterozygous in one of the probands. Deletion (del9) was revealed in a patient with cardiomyopathy and in his two daughters from different marriages, who had no clinical manifestations of the disease. All the mutations revealed in this study were previously identified in other populations.  相似文献   
7.
Currently, the potential genotoxicity of high power microwave pulses (HPMP) is not clear. Using the alkaline single cell gel electrophoresis assay, also known as the alkaline comet assay, we studied the effects of HPMP (8.8 GHz, 180 ns pulse width, peak power 65 kW, pulse repetition frequency 50 Hz) on DNA of human whole-blood leukocytes and isolated lymphocytes. The cell suspensions were exposed to HPMP for 40 min in a rectangular waveguide. The average SAR calculated from the temperature kinetics was about 1.6 kW/kg (peak SAR was about 300 MW/kg). The steady-state temperature rise in the 50 microl samples exposed to HPMP was 3.5 +/- 0.1 degrees C. In independent experiments, we did not find any statistically significant DNA damage manifested immediately after in vitro HPMP exposure of human blood leukocytes or lymphocytes or after HPMP exposure of leukocytes subsequently incubated at 37 degrees C for 30 min. Our results indicate that HPMP under the given exposure conditions did not induce DNA strand breaks, alkali-labile sites, and incomplete excision repair sites, which could be detected by the alkaline comet assay.  相似文献   
8.
Experiments were conducted on guinea pigs with the use of cell migration inhibition test of the peritoneal exudate; stimulation of a definite level of cell immunity in response to the administration of both live and of inactivated vaccine virus was shown. The results obtained are used for the interpretation of the action mechanism of the inactivated preparation in two-stage smallpox vaccination.  相似文献   
9.
The influence of mitogens on the expression of surface membrane TC-II receptors of human blood lymphocytes and internalization of (TS-II+57Co-CNCbl) complex into cytoplasm were investigated. Mature lymphocytes have a very small number of surface receptors to plasma TC-II but their expression is increased significantly by PHA or Con-A stimulation. CBl transport to cytoplasma is activated in definite sequence by two different mechanisms. Stimulated cells take free CBl without participation of TC-II in early hours of mitogen action (12-42 hrs) before maximal 3H-thymidine incorporation into DNA. On day 3 of cultivation, specific mechanism of CBl transport triggers and the number of lymphoblast receptors is increased manifold. Radioactive CBl enters cytoplasma due to interaction of TC-II-CN [57Co] CBl of the medium with surface membrane receptor of the cells. Thus, the definition of TC-II receptors as an important functional parameter may serve a marker of proliferating cells.  相似文献   
10.
Dynamics of changes of and plasma corticosterone was studied in both male and female rats after intraperitoneal injections of adrenaline at a dose of 20 micrograms per 100 g body weight. The control rats were injected with saline. Animals were decapitated 10, 30, 60, 120, 180 and 240 min after the injections. The specific effect of adrenaline was revealed in the first 10 min of adrenaline injection. This effect was significantly increased to 30-60 min after termination of saline--induced activation of the pituitary-adrenal axis. Both saline and adrenaline caused more significant increases in corticosterone levels in female rats than in male ones. There was a significant delay in the return of corticosterone to resting levels in males compared to that in females. It is supposed that the almost two-fold difference in peak plasma corticosterone concentrations observed after stressors may be associated with increased responsiveness of the female hypothalamus with respect to adrenaline secretion.  相似文献   
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