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41.
This article analyzes the indices of oxidative stress activity in freshwater bivalve Dreissena polymorpha (Pallas) from areas of the Rybinsk Reservoir with different levels of anthropogenic load. The following indices are studied: activity of catalase (CAT), glutathione reductase (GST), glutathione S-transferase (GST) and content of reduced glutathione (GSH), malondialdehyde (MDA), and carbonyl groups of oxidized proteins (CG). During the study period (July), the indices of oxidative stress of zebra mussel D. Polymorpha did not differ between sexes. Mussels that were collected in the most polluted part of the reservoir, the Sheksna stretch near the industrial complex of the city of Cherepovets, had a higher activity of catalase, glutathione S-transferase, and glutathione reductase and a higher content of malondialdehyde than zebra mussels taken from the relatively clean Volga stretch.  相似文献   
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alpha-Adrenoceptor agonists of both main groups, i. e. arylalkylamines and imidazolines, have a pronounced radioprotective effect. Their chemical analogs, which fail to stimulate alpha-adrenoceptors, do not protect mice. The effect of phenylephrine, adrenaline, and noradrenaline comes into play via alpha 1-adrenoceptors and that of clonidine, via alpha 2-adrenoceptors and also via alpha 1-adrenoceptors. Adrenoceptor agonists can probably manifest their radioprotective action via both subtypes of alpha-adrenoceptors. Possible intracellular mechanisms of the radioprotective action are discussed.  相似文献   
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Russian Journal of Bioorganic Chemistry - A radioligand-based method was proposed for quantifying the binding activity of β1-adrenergic receptors (ARs) on the surface of human T lymphocytes....  相似文献   
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Background

Protein structures are critical for understanding the mechanisms of biological systems and, subsequently, for drug and vaccine design. Unfortunately, protein sequence data exceed structural data by a factor of more than 200 to 1. This gap can be partially filled by using computational protein structure prediction. While structure prediction Web servers are a notable option, they often restrict the number of sequence queries and/or provide a limited set of prediction methodologies. Therefore, we present a standalone protein structure prediction software package suitable for high-throughput structural genomic applications that performs all three classes of prediction methodologies: comparative modeling, fold recognition, and ab initio. This software can be deployed on a user''s own high-performance computing cluster.

Methodology/Principal Findings

The pipeline consists of a Perl core that integrates more than 20 individual software packages and databases, most of which are freely available from other research laboratories. The query protein sequences are first divided into domains either by domain boundary recognition or Bayesian statistics. The structures of the individual domains are then predicted using template-based modeling or ab initio modeling. The predicted models are scored with a statistical potential and an all-atom force field. The top-scoring ab initio models are annotated by structural comparison against the Structural Classification of Proteins (SCOP) fold database. Furthermore, secondary structure, solvent accessibility, transmembrane helices, and structural disorder are predicted. The results are generated in text, tab-delimited, and hypertext markup language (HTML) formats. So far, the pipeline has been used to study viral and bacterial proteomes.

Conclusions

The standalone pipeline that we introduce here, unlike protein structure prediction Web servers, allows users to devote their own computing assets to process a potentially unlimited number of queries as well as perform resource-intensive ab initio structure prediction.  相似文献   
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Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine carcinoma of the skin. Although it is 40 times less common than malignant melanoma, its mortality is much higher compared to melanoma. From 1986 to 2001 there was rapidly increasing incidence in reported cases of MCC, with a tripling in the rate over this 15-year period. The vast majority of MCC presents on sun-exposed skin. The head and neck area is the most common site of tumor occurrence. We present 70-year old female patient with painless red-colored nodule, size 2 x 2 x 2 cm on the dorsal side of mid left forearm. The surgical excision with negative margins was performed, and pathohistological analysis confirmed Merkel cell carcinoma. Sentinel lymph node biopsy was negative. In conclusion, as MCC is a very aggressive rare skin carcinoma with lethal outcome, it should be mandatory to perform biopsies of any suspected skin lesion.  相似文献   
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Background  

Pathogen diagnostic assays based on polymerase chain reaction (PCR) technology provide high sensitivity and specificity. However, the design of these diagnostic assays is computationally intensive, requiring high-throughput methods to identify unique PCR signatures in the presence of an ever increasing availability of sequenced genomes.  相似文献   
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The possibility of using monoclonal antibodies (McAb), obtained earlier, for the detection of herpes simplex virus (HSV) in clinical specimens taken from sick and infected persons was studied. The examination of 90 persons revealed that the mixture of McAb 4A and 2C could effectively detect the presence of HSV antigen in the indirect immunofluorescence assay (IFA) directly in cells contained in cytological preparations (smears, scrapes, impressions) obtained from different organs of patients. The search of optimum combinations of McAb for the detection of HSV antigens by the method of the solid-phase enzyme immunoassay (EIA) was carried out. This study, made on purified HSV used as an experimental model, revealed that the maximum sensitivity could be achieved with the use of two McAb (4f6 and 7c4) out of three McAb (4f6, 7c4 and 3d10). The approbation of both variants of EIA on clinical specimens taken from 99 patients (blood clots, seminal fluid, scrapes of cervical canal cells, peripheral blood lymphocytes) showed that the addition of McAb 3d10 made it possible to detect 8 more positive specimens. 754 specimens from 337 patients were studied with the use of McAb-based EIA, and in 204 of these patients (61%) HSV antigen was detected. The results obtained with the use of our McAb were compared with the data obtained with certified commercial test systems. The coincidence of the EIA data with those obtained with the use of the Murex Wellcozyme HSV test system (UK) was registered in 75% of cases (in 15 out of 20 cases). The coincidence of the IFA data with those obtained with the use of the Sanofi test system (France) was observed in all 19 cases (100%).  相似文献   
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