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Estrogen-alpha receptor (ER) and progesterone receptor (PR) were examined immunohistochemically in uteri of normal bitches, in uteri of bitches with cystic endometrial hyperplasia-mucometra (CEH-M) and in uteri of bitches with endometritis-pyometra (E-P), under exogenous progesterone treatment.In the CEH-M group, the ER- and PR-scores of all uterine cell types were higher than the ER- and PR-scores of normal uteri, although these differences were not always statistically significant. The ER-scores of E-P group were significantly lower than the ER-scores of the normal uteri and CEH-M group. The PR-scores of the E-P group tended to be higher than the PR-scores of the normal uteri, except for the surface epithelium, although these differences were not statistically significant. Exogenous progesterone treated bitches with CEH-M or E-P showed reduced ER- and PR-scores in the different uterine cell types, compared with the corresponding nontreated CEH-M or E-P group.The differences in ER and PR expression between CEH-M and E-P suggest different factors in the pathogenesis of both entities. Although, these changes in ER and PR expression do not seem to be directly involved in the pathogenesis of CEH-M and E-P. It is suggested that for CEH-M and progestin induced CEH-M a hormone dependent pathway is responsible. For P, the trigger may be bacterial infection.  相似文献   
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An early warning system using a rapid enzymatic semiautomated method suitable for fecal coliform detection in recreational waters within 8 h was developed further and evaluated in this study. This rapid method was compared to the standard method followed in the United Kingdom. We used 1,011 samples originating from 206 different locations in Wales. When we assessed the presence or absence of fecal coliforms, targeting very low levels of contamination, we obtained 83.9% agreement between the rapid method and the lauryl sulfate broth-membrane filtration technique, whereas direct confirmation of the samples processed by the rapid method showed 89.3% agreement. Environmental enzymatic background activity was found to be the main limiting factor for this method. Owing to a specific and integrated handling of the results by the software of the instrument, the percentage of false-positive results (a consequence of enzymatic background) was successfully limited to 2.9% by the direct confirmation evaluation. However, 7.8% false-negative results due to “late-growers” had to be accepted in order to produce results within a working day. At present, the method can be used in a more conservative way to assess the environmental threshold of 100 CFU of fecal coliforms per 100 ml in recreational waters. The implications of our findings with regard to the applicability of rapid enzymatic methods are discussed.  相似文献   
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In this study, toxicity effects in plants of uranium in a binary pollution condition were investigated by studying biological responses and unraveling oxidative stress related mechanisms in Arabidopsis thaliana seedlings, grown on hydroponics and exposed for 3 days to 10 μM uranium in combination with 5 μM cadmium. While uranium mostly accumulated in the roots with very low root-to-shoot transport, cadmium was taken up less by the roots but showed higher translocation to the shoots. Under mixed exposure, cadmium influenced uranium uptake highly but not the other way round resulting in a doubled uranium concentration in the roots. Under our mixed exposure conditions, it is clear that micronutrient concentrations in the roots are strongly influenced by addition of cadmium as a second stressor, while leaf macronutrient concentrations are mostly influenced by uranium. Oxidative stress related responses are highly affected by cadmium while uranium influence is more limited. Hereby, an important role was attributed to the ascorbate redox balance together with glutathione as both metabolites, but more explicitly for ascorbate, increased their reduced form, indicating an important defense and regulatory function. While for roots, based on an increase in FSD1 gene expression, oxidative stress was suggested to be superoxide induced, in leaves on the other hand, hydrogen peroxide related genes were mostly altered.  相似文献   
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Field experiments were conducted in the Chernobyl-affected area to assess if short rotation coppice (SRC) for energy production is a feasible alternative for contaminated land. Four willow clones were planted on sandy and peaty soil and the radiocaesium (137Cs) and radiostrontium (90Sr) transfer factors (TF) and yield relevant parameters were recorded during four growing seasons. The 137Cs and 90Sr soil-to-willow wood TF on sandy soil (second growing season) were on average 1.40+/-1.06 x 10(-3) m2 kg(-1) and 130+/-74 x 10(-3) m2 kg(-1), respectively. The 137Cs TF recorded for the peaty soil (fourth growing season or end of the first rotation cycle) was on average 5.17+/-1.59 x 10(-3) m2 kg(-1). The 90Sr-TF was on average 2.61+/-0.44 x 10(-3) m2 kg(-1). No significant differences between clones for the 137Cs and 90Sr-TF were observed. Given the high TFs and the high deposition levels, Belarus exemption levels for fuel wood were highly exceeded. The annual average biomass production for one rotation cycle on the peaty soil ranged from 7.8 to 16.0 t ha(-1) y(-1) for one of the clones, comparable with average annual yield figures obtained for western Europe. On the sandy soils, first-year yields were 0.25 t ha(-1) y(-1). These soils are not suitable for SRC production and should better be dedicated to pine forests or drought-resistant grasses.  相似文献   
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Cyclic changes in estrogen receptor expression in the uterine tissue of 60 female dogs were evaluated, using an immunohistochemical technique on formalin-fixed paraffin-embedded sections. The expression of estrogen receptors in the uterine horns, body and cervix was quantified by means of an immunohistochemical score. A negative correlation was found between staining scores in the uterine horns and serum progesterone levels. Generally, staining scores in the uterine horns were highest during proestrus, declined during estrus and were lowest during early metestrus. During anestrus high staining scores for estrogen receptors were observed, indicating sensitivity for estrogens in a sexual quiescence stage. Compared with the uterine horns, high staining scores were found in the uterine body and cervix during estrus and metestrus. No positive staining for estrogen receptors was detected in 1 pregnant uterus. Fluctuations in estrogen receptors were more pronounced in endometrial stroma cells than in epithelial cells of the uterine horns. The importance of stromal cells in the sexual cyclicity of the canine uterus should not be underestimated when studying uterine endocrinology and pathology.  相似文献   
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Long-lived radionuclides such as 90Sr and 137Cs can be naturally or accidentally deposited in the upper soil layers where they emit β/γ radiation. Previous studies have shown that arbuscular mycorrhizal fungi (AMF) can accumulate and transfer radionuclides from soil to plant, but there have been no studies on the direct impact of ionizing radiation on AMF. In this study, root organ cultures of the AMF Rhizophagus irregularis MUCL 41833 were exposed to 15.37, 30.35, and 113.03 Gy gamma radiation from a 137Cs source. Exposed spores were subsequently inoculated to Plantago lanceolata seedlings in pots, and root colonization and P uptake evaluated. P. lanceolata seedlings inoculated with non-irradiated AMF spores or with spores irradiated with up to 30.35 Gy gamma radiation had similar levels of root colonization. Spores irradiated with 113.03 Gy gamma radiation failed to colonize P. lanceolata roots. P content of plants inoculated with non-irradiated spores or of plants inoculated with spores irradiated with up to 30.35 Gy gamma radiation was higher than in non-mycorrhizal plants or plants inoculated with spores irradiated with 113.03 Gy gamma radiation. These results demonstrate that spores of R. irregularis MUCL 41833 are tolerant to chronic ionizing radiation at high doses.  相似文献   
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