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151.
R5 variants of human immunodeficiency virus type 1 preferentially infect CD62L- CD4+ T cells and are potentially resistant to nucleoside reverse transcriptase inhibitors 下载免费PDF全文
152.
Diversity of some insect fauna in industrial and non-industrial areas of West Bengal, India 总被引:1,自引:0,他引:1
The present work is designed to study diversity of five insect orders (viz., Hemiptera, Orthoptera, aculeate Hymenoptera,
Lepidoptera and Coleoptera) in the industrial region of Haldia (India) and in non-industrial area of the same district and
to evaluate the impact of industrialization on the biodiversity of those insect orders. The objective also extended to find
out the possibility of existence of bioindicator, if any. Eight study sites were selected from the East part of Midnapur district
covering 40 km aerial distance. Out of eight different study sites, five were distributed in and around Haldia industrial
complex and three in industry-free area. During this study, a total of 120 species under 98 genera in 37 families of insects
were collected. Binary data of 5 orders revealed that the species richness of Hemiptera, Orthoptera and Lepidoptera is higher
in non-industrial zone in comparison to that of industrial zone. Aculeate Hymenoptera shows no particular trend whereas Coleoptera
shows higher species richness in industrial areas. Results of multivariate analyses are compared with the species richness
data for all the eight study sites. It is concluded that even in an apparently homogeneous ecological condition species richness
may drastically change with the influence of industries. Total insect fauna decline by at least 23.33% is noticed in industrial
areas. It is found that some species of lepidopteran, hemipteran and orthopteran insects are susceptible to industrial pollution
and some of the members of these orders may be considered as a bioindicator group. 相似文献
153.
Molecular biological methods based on genus-specific PCR, species-specific PCR, and amplified ribosomal DNA restriction analysis (ARDRA) of two PCR amplicons (523 and 914bp) using six restriction enzymes were used to differentiate among species of Bifidobacterium. The techniques were established using DNA from 16 type and reference strains of bifidobacteria of 11 species. The discrimination power of 914bp amplicon digestion was higher than that of 523bp amplicon digestion. The 914bp amplicon digestion by six restrictases provided unique patterns for nine species; B. catenulatum and B. pseudocatenulatum were not differentiated yet. The NciI digestion of the 914bp PCR product enabled to discriminate between each of B. animalis, B. lactis, and B. gallicum. The reference strain B. adolescentis CCM 3761 was reclassified as a member of the B. catenulatum/B. pseudocatenulatum group. The above-mentioned methods were applied for the identification of seven strains of Bifidobacterium spp. collected in the Culture Collection of Dairy Microorganisms (CCDM). The strains collected in CCDM were differentiated to the species level. Six strains were identified as B. lactis, one strain as B. adolescentis. 相似文献
154.
Matthew W. Pennell Mark Kirkpatrick Sarah P. Otto Jana C. Vamosi Catherine L. Peichel Nicole Valenzuela Jun Kitano 《PLoS genetics》2015,11(5)
Chromosomal fusion plays a recurring role in the evolution of adaptations and reproductive isolation among species, yet little is known of the evolutionary drivers of chromosomal fusions. Because sex chromosomes (X and Y in male heterogametic systems, Z and W in female heterogametic systems) differ in their selective, mutational, and demographic environments, those differences provide a unique opportunity to dissect the evolutionary forces that drive chromosomal fusions. We estimate the rate at which fusions between sex chromosomes and autosomes become established across the phylogenies of both fishes and squamate reptiles. Both the incidence among extant species and the establishment rate of Y-autosome fusions is much higher than for X-autosome, Z-autosome, or W-autosome fusions. Using population genetic models, we show that this pattern cannot be reconciled with many standard explanations for the spread of fusions. In particular, direct selection acting on fusions or sexually antagonistic selection cannot, on their own, account for the predominance of Y-autosome fusions. The most plausible explanation for the observed data seems to be (a) that fusions are slightly deleterious, and (b) that the mutation rate is male-biased or the reproductive sex ratio is female-biased. We identify other combinations of evolutionary forces that might in principle account for the data although they appear less likely. Our results shed light on the processes that drive structural changes throughout the genome. 相似文献
155.
156.
Cell growth and metabolite production greatly depend on the feeding of the nutrients in fed-batch fermentations. A strategy
for controlling the glucose feed rate in fed-batch baker’s yeast fermentation and a novel controller was studied. The difference
between the specific carbon dioxide evolution rate and oxygen uptake rate (Q
c − Q
o) was used as controller variable. The controller evaluated was neural network based model predictive controller and optimizer.
The performance of the controller was evaluated by the set point tracking. Results showed good performance of the controller. 相似文献
157.
Mark J. Ammirati Kim M. Andrews David D. Boyer Anne M. Brodeur Dennis E. Danley Shawn D. Doran Bernard Hulin Shenping Liu R. Kirk McPherson Stephen J. Orena Janice C. Parker Jana Polivkova Xiayang Qiu Carolyn B. Soglia Judith L. Treadway Maria A. VanVolkenburg Donald C. Wilder David W. Piotrowski 《Bioorganic & medicinal chemistry letters》2009,19(7):1991-1995
A series of 4-substituted proline amides was synthesized and evaluated as inhibitors of dipeptidyl pepdidase IV for the treatment of type 2 diabetes. (3,3-Difluoro-pyrrolidin-1-yl)-[(2S,4S)-(4-(4-pyrimidin-2-yl-piperazin-1-yl)-pyrrolidin-2-yl]-methanone (5) emerged as a potent (IC50 = 13 nM) and selective compound, with high oral bioavailability in preclinical species and low plasma protein binding. Compound 5, PF-00734200, was selected for development as a potential new treatment for type 2 diabetes. 相似文献
158.
Jana Němcová 《Mathematical biosciences》2010,223(2):83-96
Since analysis and simulation of biological phenomena require the availability of their fully specified models, one needs to be able to estimate unknown parameter values of the models. In this paper we deal with identifiability of parametrizations which is the property of one-to-one correspondence of parameter values and the corresponding outputs of the models. Verification of identifiability of a parametrization precedes estimation of numerical values of parameters, and thus determination of a fully specified model of a considered phenomenon. We derive necessary and sufficient conditions for the parametrizations of polynomial and rational systems to be structurally or globally identifiable. The results are applied to investigate the identifiability properties of the system modeling a chain of two enzyme-catalyzed irreversible reactions. The other examples deal with the phenomena modeled by using Michaelis–Menten kinetics and the model of a peptide chain elongation. 相似文献
159.
Lenka Besse Lenka Sedlarikova Fedor Kryukov Jana Nekvindova Lenka Radova Ondrej Slaby Petr Kuglik Martina Almasi Miroslav Penka Marta Krejci Zdenek Adam Ludek Pour Sabina Sevcikova Roman Hajek 《PloS one》2015,10(9)
Poor outcome of extramedullary disease in multiple myeloma patients and lack of outcome predictors prompt continued search for new markers of the disease. In this report, we show circulating microRNA distinguishing multiple myeloma patients with extramedullary disease from myeloma patients without such manifestation and from healthy donors. MicroRNA-130a was identified by TaqMan Low Density Arrays and verified by quantitative PCR on 144 serum samples (59 multiple myeloma, 55 myeloma with extramedullary disease, 30 healthy donors) in test and validation cohorts as being down-regulated in myeloma patients with extramedullary disease. Circulating microRNA-130a distinguished myeloma patients with extramedullary disease from healthy donors with specificity of 90.0% and sensitivity of 77.1%, patients with extramedullary disease from newly diagnosed multiple myeloma patients with specificity of 77.1% and sensitivity of 34.3% in the test cohort and with specificity of 91.7% and sensitivity of 30.0% in the validation cohort of patients. Circulating microRNA-130a in patients with extramedullary myeloma was associated with bone marrow plasma cells infiltration. Further, microRNA-130a was decreased in bone marrow plasma cells obtained from patients with extramedullary myeloma in comparison to bone marrow plasma cells of myeloma patients without such manifestation, but it was increased in tumor site plasma cells of patients with extramedullary disease compared to bone marrow plasma cells of such patients (p<0.0001). Together, our data suggest connection between lower level of microRNA-130a and extramedullary disease and prompt further work to evaluate this miRNA as a marker of extramedullary disease in multiple myeloma. 相似文献
160.
The extent of research on children’s speech in general and on disordered speech specifically is very limited. In this article, we describe the process of creating databases of children’s speech and the possibilities for using such databases, which have been created by the LANNA research group in the Faculty of Electrical Engineering at Czech Technical University in Prague. These databases have been principally compiled for medical research but also for use in other areas, such as linguistics. Two databases were recorded: one for healthy children’s speech (recorded in kindergarten and in the first level of elementary school) and the other for pathological speech of children with a Specific Language Impairment (recorded at a surgery of speech and language therapists and at the hospital). Both databases were sub-divided according to specific demands of medical research. Their utilization can be exoteric, specifically for linguistic research and pedagogical use as well as for studies of speech-signal processing. 相似文献