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31.
The article discusses osteonecrosis of the jaw as a possible side effect of bisphosphonate treatment. It provides practical guidelines for prevention, diagnosis and management of bisphosphonate-associated osteonecrosis according to literature and clinical evidence. Since controlled clinical trials have not been carried out, the recommendations are based on reviews, reports and clinical experience. Osteonecrosis of the jaw (ONJ) is a historical clinical entity, which can potentially develop in cancer patients receiving bisphosphonate therapy. The pathogenesis of ONJ has not been totally revealed yet. A thorough dental/oral surgical examination and counseling is recommended in cases when intravenous bisphosphonate therapy is needed. All required dental and surgical treatment should be carried out before starting bisphosphonate therapy to prevent ONJ. The patient should be informed about the possible side effects, and the importance of good oral home care and regular dental check-ups. Once the intravenous bisphosphonate therapy has started, only conservative manipulations should be carried out in the oral cavity. Even in case of developed ONJ, suspension of bisphosphonate therapy is not necessary. In these cases a non-surgical approach is recommended concerning the treatment of ONJ. Regarding the growing number of ONJ cases in association with bisphosphonate therapy it is important for the professionals treating cancer patients to be aware of this phenomenon and the importance of prevention.  相似文献   
32.
In this paper the application of microchip electrophoresis to examine the protein profile of cervicovaginal fluid and the detection of IgA heavy and light chains is presented. This method is a fast growing field of technology and ensures high-speed analysis requiring only microliters of sample. Proteins with wide range of molecular masses could be separated within 1 min. Cervicovaginal specimens of healthy women showed a complex protein pattern-containing several peaks in the 15-70 kDa region. sIgA is considered to be an important protein constituent of all mucosal surfaces. Detection of sIgA in cervicovaginal samples was achievable by microchip technology. Under reduced circumstances (induced by mercaptoethanol, a component of the denaturating solution) the disulfide bonds connecting IgA heavy and light chains are broken up and chains can be detected as separate peaks during electrophoresis. In 82.5% of the cases only the light chain of IgA could be detected in the clinical samples. The intact IgA heavy chain could be demonstrated in only 12.5% of the cases. Based on our data some conclusions were provided about the correlation of these patterns with the age of patients, pH of the cervicovaginal fluid, operations performed before sample collection and usage of oral contraceptives.  相似文献   
33.
Heavy-metal stress induced accumulation of chitinase isoforms in plants   总被引:3,自引:0,他引:3  
Plant chitinases belong to so-called pathogenesis related proteins and have mostly been detected in plants exposed to phytopathogenic viruses, bacteria or fungi. A few studies revealed that they might also be involved in plant defence against heavy metals. This work was undertaken to monitor the accumulation of chitinases in a set of heavy-metal stressed plants and bring evidence on their involvement during this kind of stress. Roots of different plant species including Vicia faba cvs. Aštar and Piešťansky, Pisum sativum, Hordeum vulgare, Zea mays and Glycine max were exposed to different concentrations of lead (300 and 500 mg l−1 Pb2+), cadmium (100 and 300 mg l−1 Cd2+) and arsenic (50 and 100 mg l−1 As3+). In each case, the toxicity effects were reflected in root growth retardation to 80–10% of control values. The most tolerant were beans, most sensitive was barley. Extracts from the most stressed roots were further assayed for chitinase activity upon separation on polyacrylamide gels. Our data showed that in each combination of genotype and metal ion there were 2–5 different chitinase isoforms significantly responsive to toxic environment when compared with water-treated controls. This confirms that chitinases are components of plant defence against higher concentrations of heavy metals. In addition, accumulation of some isoforms in response to one but not to other metal ions suggests that these enzymes might also be involved in a more (metal) specific mechanism in affected plants and their biological role is more complex than expected.  相似文献   
34.
Varga  Ildikó 《Hydrobiologia》2003,506(1-3):413-420
Hydrobiologia - Rhizome litter of Phragmites australis were enclosed in litter bags of 1 mm mesh size and submerged in a die-back reed stand of Lake Fert?/Neusiedler See (Hungary). Species...  相似文献   
35.
Molecular and Cellular Biochemistry - Deuterium (D) is a stable isotope of hydrogen (H) with a mass number of 2. It is present in natural waters in the form of HDO, at a concentration of...  相似文献   
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37.
Changing climatic conditions with warming winters and shifts in the frequencies of drought, intense rainfall and cold spells together with associated changes in the geographical distribution of arable crops increase the challenges for selecting new varieties. In this context, we aim to contribute to a better understanding of the determinants of barley (Hordeum vulgare) frost tolerance (FRT) and consequent improvements to marker-assisted selection (MAS). Freezing injury in a diversity panel of 121 barley genotypes with different growth habits and origins was assessed using phenotyping based on chlorophyll fluorescence (Fv/Fm) measurements to screen genetic diversity in plants at an early growth stage. The haplotypes of vernalisation and photoperiod genes were determined with PCR, and correlation analyses were done using data from 12 laboratory and field-laboratory FRT tests. Previous results of allelic combinations of VRN-H1/VRN-H2 for FRT were confirmed with these experiments using a larger set of genotypes. The predictive power of polymorphisms in VRN-H1 intron 1 region for FRT was significantly higher than that of the VRN-H1 promoter polymorphism. The vrn-H1/vrn-H2 facultative genotypes had similar or higher FRT than vrn-H1/Vrn-H2 winter genotypes under suboptimal hardening conditions. Genes regulating long-day and short-day photoperiodic responses were significantly correlated with FRT. The most parsimonious model for prediction of FRT was based on polymorphisms in the VRN-H1 intron 1 region, VRN-H2 and PPD-H2 and explained 69% of the variation in FRT.  相似文献   
38.
Climate change may affect species diversity and, consequently, ecological processes such as leaf decomposition. We evaluated the effects of increased temperature and carbon dioxide (CO2) on fungal biomass, leaf breakdown, and on survival and growth of the shredder Phylloicus elektoros. We hypothesized that climatic changes would result in lower survival and growth of shredders and lower leaf consumption by these organisms. On the other hand, we predicted an increase in fungal biomass in response to climatic changes. We conducted an experiment in Manaus, Brazil, using four microcosms that simulate real-time air temperature and CO2 (control chamber), as well as three other chambers subjected to fixed increases in temperature and CO2 as compared to the control chamber. The “extreme” condition represented an increase of ~4.5°C in temperature and ~870 ppm in CO2 in relation to the control chamber. Total and shredder leaf-breakdown rates, fungal biomass, and shredder survival rates were significantly lower in warmer and CO2 concentrated atmospheres. Shredder growth rate and leaf breakdown by microorganisms were similar among all climatic conditions. With climatic changes, we found an increase in the relative importance of microorganisms on leaf-breakdown rates as compared to shredders. Thus, lower leaf breakdown and a change in the main decomposer due to future climatic conditions may result in major changes in the pathways of organic matter processing and, consequently, in aquatic food webs.  相似文献   
39.
Several isoforms of connexin (Cx) proteins have been identified in a variety of tissues where they play a role in intercellular communication, either as the components of gap junctions or as large, nonselective pores known as hemichannels. This investigation seeks to identify the localization and regulation of Cx30.3 in mouse, rat, and rabbit kidney using a Cx30.3(+/lacZ) transgenic approach and immunofluorescence. Cx30.3 was detected in all three species and predominantly in the renal medulla. Both the nuclear lacZ staining indicative of Cx30.3 expression and indirect immunohistochemistry provided the same results. Cx30.3 immunolabeling was mainly punctate in the mouse, typical for gap junctions. In contrast, it showed continuous apical plasma membrane localization in certain tubule segments in the rat and rabbit kidney, suggesting that it may also function as hemichannels. In the cortex, Cx30.3 was localized in the intercalated cells of the cortical collecting duct, because the immunoreactive cells did not label for AQP2, a marker for principal cells. In the medulla, dense Cx30.3 staining was confined to the ascending thin limbs of the loop of Henle, because the immunoreactive cells did not label for AQP1, a marker of the descending thin limbs. Immunoblotting studies indicated that Cx30.3 expression was unchanged in response to either high or low salt intake or in spontaneously hypertensive rats. Cx30.3 appears to be constitutively expressed in certain renal tubular segments and cells and its role in overall kidney function remains to be investigated.  相似文献   
40.
A vegetation survey was carried out in a relatively intact Atlantic blanket bog in Southwest Ireland to study the vegetation patterns in relation to environmental variation, and to quantify the effect of artificial and natural borders on compositional variation. The data were analysed using canonical correspondence analysis. In terms of both vegetation and water chemistry, the study site can be categorized as typical of Atlantic blanket bogs in the maritime regions of North-western Europe. The distribution of plant species was explained mainly by depth of the water table. The distribution of bryophytes was secondarily explained by the pH of the bog water, while the distribution of vascular plants was secondarily explained by concentrations of ammonia. The vegetation distribution exhibited little variation between the central sector of the peatland and its disturbed edges (hill-grazing and restoration areas), but a substantial variation was observed between the area along a natural edge (stream) and the areas close to the other peatland borders or centre. Similarly, the internal variation within each sector (centre, hill-grazing edge and restoration area edge) was small, but substantial vegetation variation was observed within the area located along the stream. The area along the stream was associated with relatively deep water table, shallow peat depth, high water colour, pH and NH4 + concentrations, and low Cl concentrations in the bog water. Our results suggest the existence of strong centre-natural margin gradients, as in raised bogs, and indicate that human or animal disturbance do not give rise to the marked transition zones that often characterize natural margins of mire systems. This indicates that even small areas and remnants of Atlantic blanket bogs are worthy of conservation and that their conservation value would benefit from the inclusion of sectors close to the natural peatland borders, which would increase the plant biodiversity of the conserved area.  相似文献   
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