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1.
The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants.  相似文献   
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Glioblastomas (GBL) are the most common and aggressive brain tumors. They are distinguished by high resistance to radiation and chemotherapy. To find novel approaches for GBL classification, we obtained 16 primary GBL cell cultures and tested them with real-time PCR for mRNA expression of several genes (YB-1, MGMT, MELK, MVP, MDR1, BCRP) involved in controlling cell proliferation and drug resistance. The primary GBL cultures differed in terms of proliferation rate, wherein a group of GBL cell cultures with low proliferation rate demonstrated higher resistance to temozolomide. We found that GBL primary cell cultures characterized by high proliferation rate and lower resistance to temozolomide expressed higher mRNA level of the YB-1 and MDR1 genes, whereas upregulated expression of MVP/LRP mRNA was a marker in the group of GBL with low proliferation rate and high resistance. A moderate correlation between expression of YB-1 and MELK as well as YB-1 and MDR1 was found. In the case of YB-1 and MGMT expression, no correlation was found. A significant negative correlation was revealed between mRNA expression of MVP/LRP and MELK, MDR1, and BCRP. No correlation in expression of YB-1 and MVP/LRP genes was observed. It seems that mRNA expression of YB-1 and MVP/LRP may serve as a marker for GBL cell cultures belonging to distinct groups, each of which is characterized by a unique pattern of gene activity.  相似文献   
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Method of Pneumocystis carinii DNA detection in clinical samples (sputum) is presented. Primers to one fragment of 16S rRNA gene were used for detection of DNA. Isolation and amplification of DNA were performed in presence of internal DNA control. Analytical sensitivity of method was 200 copies of DNA per 1 ml. Analytical and diagnostic specificities were 100% and 95% accordingly. Sputum from 176 children with frequent respiratory infections were sampled before start of antibacterial therapy and studied simultaneously by the polymerase-chain reaction (PCR) and immunofluorescent assay (IFA). Results of PCR and IFA coincided in 167 (94.89%) children. From them, P.carinii was detected in sputum in 5 (2.85%) children. All children with positive results were treated with antibiotics. Repeated tests of sputum 8 days after start of treatment were all negative. PCR could be recommended as part of complex of clinical diagnostics and control of treatment.  相似文献   
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Russian Journal of Bioorganic Chemistry - The composition of phenolic compounds of rowanberry (Sorbus aucuparia L.) fruit extracts prepared with 40% ethanol and 95% acidified ethanol was studied....  相似文献   
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One hundred eighty nine children with acute bronchopulmonary infectious pathological processes were examined bacteriologically and serologically for typical pneumotropic pathogens, 47 of them being as well examined for atypical organisms. Microbial associations mainly with Mycoplasma and Pneumocystis and to a lesser extent with Chlamydia were isolated from the majority of the children. Reactivation of the cytomegalovirus infection was observed in 25 per cent of the children. Pneumonia and bronchitis due to Mycoplasma pneumoniae either as a monoagent or in associations were mainly stated in children over 7 years of age. No significant changes between the indices of the infection due to a definite organism and the active progression of the infectious process of the same etiology were revealed, though in the cases of chlamydiosis the changes reached almost 10 per cent. In cases of acute bronchitis and pneumonia the chlamydial or cytomegalovirus infection could be assumed to be of the persisting nature, mainly acute in cases of pneumococcal infection, mixed in cases of hemophilic or pneumocystic infection, primary contamination with a tendency to prolonged in cases of mycoplasmic infection. The findings of the examination and the clinical and anamnestic data showed that the clinical picture of acute pneumonia had specific features associated with the supposed etiological agents, still it could change under the action of associations of pneumotropic pathogens.  相似文献   
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Background  

Multidrug resistance (MDR) phenotype of malignant cells is the major problem in the chemotherapy of neoplasia. The treatment of leukemia with retinoids is aimed on the induction of leukemic cells differentiation. However the interconnections between retinoid regulated differentiation of leukemic cells and regulation of MDR remains unclear.  相似文献   
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Background  

The distribution area of pearl millet in West and Central Africa (WCA) harbours a wide range of climatic and environmental conditions as well as diverse farmer preferences and pearl millet utilization habits which have the potential to lead to local adaptation and thereby to population structure. The objectives of our research were to (i) assess the geographical distribution of genetic diversity in pearl millet inbreds derived from landraces, (ii) assess the population structure of pearl millet from WCA, and (iii) identify those geographical parameters and environmental factors from the location at which landraces were sampled, as well as those phenotypic traits that may have affected or led to this population structure. Our study was based on a set of 145 inbred lines derived from 122 different pearl millet landraces from WCA.  相似文献   
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