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1.
We have evaluated codon usage bias in Drosophila histone genes and have obtained the nucleotide sequence of a 5,161-bp D. hydei histone gene repeat unit. This repeat contains genes for all five histone proteins (H1, H2a, H2b, H3, and H4) and differs from the previously reported one by a second EcoRI site. These D. hydei repeats have been aligned to each other and to the 5.0-kb (i.e., long) and 4.8-kb (i.e., short) histone repeat types from D. melanogaster. In each species, base composition at synonymous sites is similar to the average genomic composition and approaches that in the small intergenic spacers of the histone gene repeats. Accumulation of synonymous changes at synonymous sites after the species diverged is quite high. Both of these features are consistent with the relatively low codon usage bias observed in these genes when compared with other Drosophila genes. Thus, the generalization that abundantly expressed genes in Drosophila have high codon bias and low rates of silent substitution does not hold for the histone genes.   相似文献   
2.
Mouse Monoclonal antibodies against human adiponectin were produced by the routine method and the specificity of antibodies was verified. These monoclonal antibodies (MoAbs) interacted with the monomeric and trimeric forms of recombinant adiponectin according to the results of a Western blot analysis. Human blood serum was fractionated by gel filtration, and the protein of these fractions was stained using labeled MoAbs. It was established that a single high-molecular-weight form (HMW) of endogenous adiponectin was detected by this method. The use of competitive enzymelinked immunoassay on the basis of the obtained MoAbs allowed us to show that the sera of healthy male donors contains lower adiponectin concentrations than that of female donors (8.42 ± 1.59 μg/ml vs. 11.01 ± 2.58 μg/ml, p = 0.01). We also detected statistically significant lower adiponectin levels in the serum of patients with coronary artery disease for both men (6.01 ± 2.73 μg/ml vs. 8.42 ± 1.59 μg/ml, p = 0.015) and women (5.79 ± 2.98 μg/ml vs. 11.01 ± 2.58 μg/ml, p = 0.0003). Therefore, the developed methods for the analysis of the HMW form of adiponectin can be helpful in the diagnostics of the possible implications and assessment of unfavorable prognoses in patients with cardiovascular disorders.  相似文献   
3.
There is a need for safe medications that can effectively support recovery by treating symptoms of protracted abstinence that may precipitate relapse in alcoholics, e.g. craving and disturbances in sleep and mood. This proof-of-concept study reports on the effectiveness of gabapentin 1200 mg for attenuating these symptoms in a non-treatment-seeking sample of cue-reactive, alcohol-dependent individuals. Subjects were 33 paid volunteers with current Diagnostic and Statistical Manual of Mental Disorders-IV alcohol dependence and a strength of craving rating 1 SD or greater for alcohol than water cues. Subjects were randomly assigned to gabapentin or placebo for 1 week and then participated in a within-subjects trial where each was exposed to standardized sets of pleasant, neutral and unpleasant visual stimuli followed by alcohol or water cues. Gabapentin was associated with significantly greater reductions than placebo on several measures of subjective craving for alcohol as well as for affectively evoked craving. Gabapentin was also associated with significant improvement on several measures of sleep quality. Side effects were minimal, and gabapentin effects were not found to resemble any major classes of abused drugs. Results suggest that gabapentin may be effective for treating the protracted abstinence phase in alcohol dependence and that a randomized clinical trial would be an appropriate next step. The study also suggests the value of cue-reactivity studies as proof-of-concept screens for potential antirelapse drugs.  相似文献   
4.
The study aimed to explore the suicidal process, suicidal communication and psychosocial situation of young suicide attempters in a rural community in Hanoi, Vietnam. Semi-structured interviews were conducted, in a community setting, with 19 suicide attempters aged 15-24 who had been consecutively hospitalized in an intensive care unit. In 12 of 19 cases, the first pressing, distinct and constant suicidal thoughts appeared less than one day before the suicide attempt in question. However, distress and mild, fleeting suicidal thoughts had been present up to six months before the suicide attempt in 16 cases. Five respondents had a suicide plan one to three days before attempting suicide. Altogether, 13 engaged in some form of suicidal communication before their attempt. This communication was, however, difficult for outsiders to interpret. Twelve of the respondents were victims of regular physical abuse and 16 had suffered psychological violence for at least one year before attempting suicide. Eighteen of the respondents used pesticides or raticides in their suicide attempts. None sought advice or consultation in the community despite long-standing psychosocial problems. The strategy of reducing the availability of suicide means (e.g., pesticides or raticides) in Asian countries should be complemented with a long-term suicide-preventive strategy that targets school dropouts and domestic violence, and promotes coping abilities and communication about psychological and social problems as well as recognition of signs of distress and suicidal communication.  相似文献   
5.
6.
The intermolecular noncovalent binding of complementary fibrin polymerization sites localized in fibrin domains D and E was investigated in the model system. In this system fibrinogen molecules represent the active D domains and the N-terminal disulphide knot of fibrin (N-DSK) represents the active E domain. Quantitative definition of insoluble fibrinogen and N-DSK copolymer and light scattering data of their mixtures before the appearance of visible precipitate show that complexing of these structures decreases with an increase of the temperature and ionic strength. The character of this dependence permits certain conclusions to be made on the functioning mechanism for two types of the D-E binding sites. These conclusions are based on an idea of their different affinity. The interdomain binding is primarily realized by D1-E1 sites which are characterized by a high affinity and work mainly on the basis of electrostatic forces. This binding directs the D2-E2 binding which is characterized by lower affinity and which determines the final degree of fibrinogen and N-DSK complexing. These sites function mainly by the H-binding.  相似文献   
7.
Peptides Gly-Pro-Arg-Pro and Gly-His-Arg-Pro (fibrin alpha- and beta-chain NH2-terminal analogs, respectively) are studied for their effect on fibrinogen (F) and fibrin NH2-terminal disulphide knot (N-DSK) specific binding. Both peptides are found to inhibit the formation of soluble and insoluble F-N-DSK-complexes through inhibition of the interdomain D-E-binding. Gly-Pro-Arg-Pro is much more potent inhibitor than Gly-His-Arg-Pro. Lowering the insoluble F-N-DSK-copolymer quantity by concentration-dependent way these peptides do not change its composition described by the formula [F(N-DSK)2]n. Invariability of fibrinogen and N-DSK copolymer structure is asserted. In this structure neighbouring fibrinogen molecules are bound by two N-DSK molecules via the D1-E1 and D2-E2 binding sites.  相似文献   
8.
The study on sensitivity of clinical strains of the causative agents of purulent infections to carbenicillin showed that 34.6% of the staphylococcal strains, 48.1% of the E. coli strains and 40.3% of the Proteus strains were sensitive to the antibiotic. The strains of Ps. aeruginosa were characterized by moderate sensitivity to carbenicillin. The MTC for most of the isolates ranged within 25-128 microgram/ml. High therapeutic efficacy of carbenicillin in treatment of cases with purulent inflammatory processes of various localization was shown. Positive results were obtained in 82.5% of the adults and 76.2% of the premature infants treated with carbenicillin. A satisfactory therapeutic effect was observed in the cases with sepsis, diffuse purulent peritonitis and abscessing pneumonia treated with carbenicillin in combination with gentamicin.  相似文献   
9.
The oil-oxidizing potential of associative rhizobacteria of the genus Azospirillum was studied under laboratory conditions. After screening, A. brasilense strain SR80 was chosen for further investigation. The strain was capable of degrading 56.5% of crude oil (added in a concentration of 1%) over 14 days in a medium containing malate as an additional source of carbon and energy. Studies of associative properties showed that the strain had positive chemotaxis to wheat root exudates, colonized wheat roots, and produced indolyl-3-acetic acid. The synthesis of indolyl-3-acetic acid was not inhibited by oil. Under hydroponic conditions, crude oil stimulated growth of A. brasilense SR80, which promoted development of the wheat root system in the presence of oil and enhanced the level of oil degradation by the plant-microbial association.  相似文献   
10.
It has been shown that the fungus Lentinus edodes grown on a solid wort agar substrate produces intracellular enzymes, including Mn-dependent peroxidase, laccase, and tyrosinase as a family of isoforms. The composition of the complex (containing one to four forms of each enzyme) varied during the basidiomycete life cycle. The activity of oxidases was maximal at the stage of nonpigmented mycelium and at the stages of a brown mycelial mat and a fruit body. The activity of tyrosinase increased in the course of mycelium pigmentation and had two maxima: at the stage of a brown mycelial mat and at the stage of a fruit body. Laccase and tyrosinase activities were shown to increase sharply upon addition of oak sawdust extract to the culture medium as compared with the enzyme activities of mycelium grown on wort agar alone. It was established that the effect of phenol oxidase substrates on the growing mycelium consists in a twofold acceleration of the process of morphogenesis in the fungus L. edodes.  相似文献   
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