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1.
In experiments on CBA mice it was shown that migration of 51Cr-labeled spleen lymphocytes, injected intravenously, to lymph nodes of intact recipients was suppressed 6-24 months after the administration of a radiopharmaceutic preparation of selenium-75-selenomethionine in a quantity forming the doses of 1 Gy and 1.5 Gy absorbed within the whole body and lymphoid organs, respectively. Migration of labeled lymphocytes to the liver, kidneys and lungs, as well as their retention in the circulating blood, were increased. As the result of the migration disorders the specific affinity of lymphocytes for peripheral lymphoid tissue decreased.  相似文献   
2.
The localization of a gene responsible for a normal variant of the human electroencephalogram to the distal part of chromosome 20q is reported. A linkage analysis, including 17 families with 191 individuals, tested with 73 RFLPs and 22 blood and serological markers, was performed for the low-voltage electroencephalogram. This is a normal variant of the human electroencephalogram with an autosomal dominant mode of inheritance. The results present strong evidence for close linkage with the highly polymorphic marker CMM6 (D20S19) and for genetic heterogeneity.  相似文献   
3.
In the adoptive transfer system of (CBA X C57BL/6)F1 mice, the estimation was made of the function of splenic cells, suppressors of the humoral immune response to sheep erythrocytes 1 and 6 months following the injection of 125I and 131I. Low absorbed doses of the radioactive isotopes were shown to stimulate the activity of the suppressors generated in mouse spleen.  相似文献   
4.
The syngeneic transfer system was used to study migration of 51Cr-labelled spleen lymphocytes in mice after incorporation of beta-emitter, 35S-methionine. Migration of 51Cr-labelled lymphocytes to lymph nodes was stably decreased, and to liver, kidneys and lungs increased. The lymphocyte migration impairment was associated with the influence of beta-radiation on both the migratory properties of cells and the factors of their microenvironment responsible for the lymphocyte migration within the mouse body. No distinctions were observed in the character and manifestation of disturbances of the lymphocyte migration after the injection of 35S-methionine and gamma-emitter, 75Se-selenomethionine.  相似文献   
5.
KV Thomas 《Biofouling》2013,29(1):73-86

Antifouling paint booster biocides are a group of organic compounds added to antifouling paints to improve their efficacy. They have become prevalent since the requirement for alternative antifouling paints formulations for small boats (< 25 m). This need followed a ban on the use of triorganotin biocides in antifouling paints for small boats, in the late 1980's. Worldwide, around eighteen compounds are currently used as antifouling biocides, viz. benzmethylamide, chlorothalonil, copper pyrithione, dichlofluanid, diuron, fluorofolpet, Irgarol 1051, Sea‐Nine 211, Mancozeb, Polyphase, pyridine‐triphenyl‐borane, TCMS (2,3,5,6‐tetrachloro‐4‐methylsulfonyl) pyridine, TCMTB [2‐(thiocyanomethylthio)benzothia‐zole], Thiram, tolyfluanid, zinc pyrithione (ZPT), ziram and Zineb. Any booster biocide released into the environment is subjected to a complex set of processes. These processes include transport mechanisms, transformation, degradation, cross media partitioning, and bioaccumulation. This paper reviews the fate and behaviour data currently available in the public domain concerning antifouling paint booster biocides.  相似文献   
6.
Genetic influences on alcohol and drug dependence partially overlap, however, specific loci underlying this overlap remain unclear. We conducted a genome‐wide association study (GWAS) of a phenotype representing alcohol or illicit drug dependence (ANYDEP) among 7291 European‐Americans (EA; 2927 cases) and 3132 African‐Americans (AA: 1315 cases) participating in the family‐based Collaborative Study on the Genetics of Alcoholism. ANYDEP was heritable (h 2 in EA = 0.60, AA = 0.37). The AA GWAS identified three regions with genome‐wide significant (GWS; P < 5E‐08) single nucleotide polymorphisms (SNPs) on chromosomes 3 (rs34066662, rs58801820) and 13 (rs75168521, rs78886294), and an insertion‐deletion on chromosome 5 (chr5:141988181). No polymorphisms reached GWS in the EA. One GWS region (chromosome 1: rs1890881) emerged from a trans‐ancestral meta‐analysis (EA + AA) of ANYDEP, and was attributable to alcohol dependence in both samples. Four genes (AA: CRKL, DZIP3, SBK3; EA: P2RX6) and four sets of genes were significantly enriched within biological pathways for hemostasis and signal transduction. GWS signals did not replicate in two independent samples but there was weak evidence for association between rs1890881 and alcohol intake in the UK Biobank. Among 118 AA and 481 EA individuals from the Duke Neurogenetics Study, rs75168521 and rs1890881 genotypes were associated with variability in reward‐related ventral striatum activation. This study identified novel loci for substance dependence and provides preliminary evidence that these variants are also associated with individual differences in neural reward reactivity. Gene discovery efforts in non‐European samples with distinct patterns of substance use may lead to the identification of novel ancestry‐specific genetic markers of risk.  相似文献   
7.

Background

The function of proteins is a direct consequence of their three-dimensional structure. The structural classification of proteins describes the ways of folding patterns all proteins could adopt. Although, the protein folds were described in many ways the functional properties of individual folds were not studied.

Results

We have analyzed two β-barrel folds generally adopted by small proteins to be looking similar but have different topology. On the basis of the topology they could be divided into two different folds named SH3-fold and OB-fold. There was no sequence homology between any of the proteins considered. The sequence diversity and loop variability was found to be important for various binding functions.

Conclusions

The function of Oligonucleotide/oligosaccharide-binding (OB) fold proteins was restricted to either DNA/RNA binding or sugar binding whereas the Src homology 3 (SH3) domain like proteins bind to a variety of ligands through loop modulations. A question was raised whether the evolution of these two folds was through DNA shuffling.  相似文献   
8.
The enzyme immunoassay system (EIA) for differentiation of antibodies in therapeutic heterogeneous antitoxic serum and antibodies to Corynebacterium diphtheriae toxigenic strains in patients and carriers was developed. The use of EIA permitted the dynamic evaluation of the characteristics of humoral antitoxic and antibacterial immune response in 50 patients with the localized and disseminated forms of stomatopharyngeal diphtheria and 14 "healthy" carriers of toxigenic C. diphtheriae. As revealed in this study, the symptoms of the disease in patients with disseminated forms of stomatopharyngeal diphtheria developed in the presence of statistically significant low quantitative values of antitoxic and antibacterial antibodies to C. diphtheriae antigens. In the group of patients with the localized forms of the disease the initially low level of antitoxic antibodies was detected with the concentration of antibacterial antibodies remaining unchanged. During the period of convalescence the levels of antitoxic antibodies in both groups reached those of healthy persons. In case of localized forms of the disease the level of antibacterial antibodies decreased as compared with healthy persons, starting from the second week of the disease. The period of convalescence in the disseminated forms was characterized by the low concentration of antibacterial antibodies. Carrier state was formed in the presence of high levels of antitoxic antibodies and significantly low levels of antibacterial ones.  相似文献   
9.
The typology analysis of the spectral density curves of time series obtained from various parameters of unit pulse oscillations was performed. The formal classification (typology) of spectral curves was performed using correlations of peak values of the spectral density of VLF, LF, and HF slow waves. To include a spectral density curve into a particular type, the criteria were introduced that characterize the intensity of these oscillatory components. The experimental data was collected during examinations of children and adolescents that were performed to detect the early stage of arterial hypertension (AH). The distribution of the subjects among the types of spectral density based on various parameters of pulse oscillation was evaluated. The results of the comparative analysis of spectral type distribution for various parameters are shown. This analysis has revealed the most informative spectral parameters for differential diagnosis of conditions of two types: type 1, essential hypertension, and type 2, various functional disorders with a normal blood pressure. It has been found that the parameters of the oscillatory components of dicrotic pulse wave time characteristics are the most informative for detecting hypertension in children.  相似文献   
10.
The plasticity of neural networks is a complex process determined by changes in physiological status, gene expression and phenotype of a cell. A detailed study of this process dynamics requires the simultaneous recording of electrical and genomic activities in networks of neurons. This sets up one of the tasks for modern neuroscience as development of integration of electrophysiology and molecular biology methods. In the paper we review the current approaches to such integration, as well as the choice of molecular markers for detection of genomic and synaptic plasticity of neurons by use of physiological micro-sensorial system based on neuronal cells cultured on the micro-electrode arrays.  相似文献   
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