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991.
Microcystin synthetase-gene-specific primers were used to identify hepatotoxic microcystin producing genotypes in six Microcystis spp.-dominant water blooms. Four blooms gave positive PCR reaction. They produced microcystin-RR and -LR amounting to 0.037 to 0.095% of the dry mass.  相似文献   
992.
Objective: To describe changes in the distribution of waist circumference (WC) and abdominal obesity (AO) in white, black, and Mexican‐American adults from 1988 through 2000. Research Methods and Procedures: Nationally representative cross‐sectional surveys of adults 20 to 79 years of age were examined using data from U.S. National Health and Nutrition Examination Surveys of 1988 to 1994 and 1999 to 2000. AO was defined as WC ≥102 cm in men and ≥88 cm in women. Results: There was a gradient of increasing WC and AO with increasing age in both study periods in whites and blacks. In men, the average increase between the study periods in overall WC in whites, blacks, and Mexican Americans were 3, 3.3, and 3.4 cm, respectively. The corresponding values in women were 2.4, 5.3, and 3.7 cm, respectively. In men, the percentage change in prevalence of AO between 1988 and 2000 ranged from 5.5% in Mexican‐American men to 8.2% in white men. In women, there was a 1.7% decrease in AO in Mexican Americans, whereas there was an increase of 6.3% for whites and 7% for blacks. Discussion: Despite increased understanding of the need for screening and treatment for obesity, this study indicates increasing prevalence of AO in white and black Americans. Without concerted effort to reduce the prevalence of overall obesity, the increasing prevalence of AO is likely to lead to increased prevalence of metabolic syndromes in the United States. Our results highlight the need to design evidence‐based programs that show promise for long‐term health behavior changes to facilitate the prevention of AO and related comorbidities.  相似文献   
993.
One hundred children with suspected congenital and/or malformation and their parents who reported to SAT hospital, Medical College, Trivandrum, India formed the test group. Fifty children with no obvious anomalies or abnormalities and their parents formed the control group. The criteria for selection of the control was (1) the maternal age at delivery was below 30 years and (2) the parents belong to first or second birth order. The chromosomal analysis was carried out in all the subjects using peripheral blood lymphocyte microculture to investigate any constitutional chromosomal markers and quantitate the mutagen (bleomycin) sensitivity of the chromosomes. All the subjects were evaluated clinically and a complete family history was recorded. Chromosome anomalies were noted in 41 out of 100 children and in 4 out of 200 parents of the test group. No constitutional aberrations were seen either in the parents or in the children of the control group. Bleomycin sensitivity study revealed a high b/c value in 35 children (24 hypersensitive and 11 sensitive) of the test group whereas in the control group the b/c values were low denoting hyposensitivity and very good DNA repair mechanism. This study reveals that the incidence of chromosome aberrations is higher when the age and birth order of parents are higher. A direct correlation was noted with parental order and b/c value. This was also true with the parental age and birth defects.  相似文献   
994.
995.
Malaria is an important tropical infection which urgently requires intervention of an effective vaccine. Antigenic variations of the parasite and allelic diversity of the host are main problems in the development of an effective malaria vaccine. Cytotoxic T lymphocytes (CTL) directed against Plasmodium falciparum­derived antigens are shown to play an important role for the protection against malaria. The merozoite surface protein 1 (MSP1) is expressed in all the four life-cycle stages of Plasmodium falciparum and did not find any sequence similarity to human and mouse reference proteins. MSP1 is a known target of the immune response and a single CTL epitope binding to the HLA­A*0201 is available for merozoite form. Here, we report the results from the computational characterization of MSP1, precursor (1720 residue) and screening of highest scoring potential CTL epitopes for 1712 overlapping peptides binding to thirty four HLA class­I alleles and twelve HLA class­I supertypes (5 HLA­A and 7 HLA­B) using bioinformatics tools. Supertypes are the clustered groups of HLA class­I molecules, representing a sets of molecules that share largely overlapping peptide binding specificity. The prediction results for MSP1 as adhesin and adhesin-like in terms of probability is 1.0. Results also show that MSP1 has orthologs to other related species as well as having non allergenicity and single transmembrane properties demonstrating its suitability as a vaccine candidate. The predicted peptides are expected to be useful in the design of multi-epitope vaccines without compromising the human population coverage.  相似文献   
996.
In this paper, we present numerical evidence that supports the notion of minimization in the sequence space of proteins for a target conformation. We use the conformations of the real proteins in the Protein Data Bank (PDB) and present computationally efficient methods to identify the sequences with minimum energy. We use edge-weighted connectivity graph for ranking the residue sites with reduced amino acid alphabet and then use continuous optimization to obtain the energy-minimizing sequences. Our methods enable the computation of a lower bound as well as a tight upper bound for the energy of a given conformation. We validate our results by using three different inter-residue energy matrices for five proteins from protein data bank (PDB), and by comparing our energy-minimizing sequences with 80 million diverse sequences that are generated based on different considerations in each case. When we submitted some of our chosen energy-minimizing sequences to Basic Local Alignment Search Tool (BLAST), we obtained some sequences from non-redundant protein sequence database that are similar to ours with an E-value of the order of 10-7. In summary, we conclude that proteins show a trend towards minimizing energy in the sequence space but do not seem to adopt the global energy-minimizing sequence. The reason for this could be either that the existing energy matrices are not able to accurately represent the inter-residue interactions in the context of the protein environment or that Nature does not push the optimization in the sequence space, once it is able to perform the function.  相似文献   
997.
The mass transfer in an eccentric annular region through diffusion by taking blood as a Newtonian fluid with the investigation of oxygen transfer and drug transport to the tissue cells in an eccentric catheterized artery is studied. The region bounded by eccentric circles in x-y plane is mapped conformally to concentric circles in \(\xi -\eta\) plane using a conformal mapping \(z = \lambda /1 - \zeta\). The resulting governing equations are analytically solved by using transformation for the concentration. Numerical computations are carried out to understand the simultaneous~effects of absorption parameter and eccentricity on the flow. ~The observation through the numerical computation reveals that, as absorption parameter and eccentricity enhances, the solute concentration diminishes. This mathematical model provides an insight for physiologists to understand the drug transport to the tissues in various clinical treatments of cardiovascular diseases.  相似文献   
998.
A series of 2-sulfonyl-4H-3,1-benzoxazinones was prepared that inhibit C1r protease in vitro. Several compounds were found to be selective for C1r verses the related serine protease trypsin. Selected compounds demonstrated functional activity in a hemolysis assay.  相似文献   
999.
A specific 5′ NH2 labeled DNA probe of speB gene was immobilized onto the gold nanoparticles/carboxylated multi walled carbon nanotubes (Nano-Au/cMWCNT) screen printed electrode using EDC/NHS cross linking chemistry. This was followed by hybridization with 0.5–50 ng/6 µl of single stranded genomic DNA Streptococcus pyogenes infected patient throat swab samples. Electrochemical amperometric assay was deciphered by using cyclic voltammetry (CV) with methylene blue a redox indicator. The sensor had a sensitivity of 104.7 µA cm?2 ng?1 using CV with a R2 of 0.907 and 0.01 ng/6 µl as the limit of detection (LOD). The modified electrode surface morphology was characterized using scanning electron microscopy. The stability of the electrode was seen at 4 °C for 180 days having 6% loss in the initial current. The sensor is speB gene specific and can detect the pathogen within 30 min.  相似文献   
1000.
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