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41.
42.
Ganesh Kumar Veeramachaneni K Kranthi Raj Leela Madhuri Chalasani Sai Krishna Annamraju Bondili JS Venkateswara Rao Talluri 《Bioinformation》2015,11(12):535-542
Increase in obesity rates and obesity associated health issues became one of the greatest health concerns in the present world
population. With alarming increase in obese percentage there is a need to design new drugs related to the obesity targets. Among
the various targets linked to obesity, pancreatic lipase was one of the promising targets for obesity treatment. Using the in silico
methods like structure based virtual screening, QikProp, docking studies and binding energy calculations three molecules namely
zinc85531017, zinc95919096 and zinc33963788 from the natural database were reported as the potential inhibitors for the pancreatic
lipase. Among them zinc95919096 presented all the interactions matching to both standard and crystal ligand and hence it can be
further proceeded to drug discovery process. 相似文献
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45.
Theodore H. DeWitt Jeffrey S. Levinton 《Journal of experimental marine biology and ecology》1985,92(1):97-113
In the presence of the mud snail Ilyanassa obsoleta (Say), the tubicolous amphipod Microdeutopus gryllotalpa (Costa) emigrates to snail-free sediments, as demonstrated in laboratory and field experiments. Emigration occurs predominantly in the dark when the amphipod is most active. Unlike crevices, the thickness of sediments in which the amphipod is established offers no protection from snail disturbance. Emigration is shown to be caused by the disturbance generated by the snail's plowing and burrowing across the sediment surface, and not a response to a reduction in the shared microfloral food supply. The crawling and burrowing of the smaller mud snail, Hydrobia totteni Morrison, does not disturb Microdeutopus, supporting the hypothesis that relative body sizes affects the ability of bioturbators/burrowers to disturb tube-dwellers. As the burrows of Microdeutopus extend only ≈2 cm below the sediment surface, thick mud layers do not offer any refuge from Ilyanassa. However, very small solid surfaces (≈1–2 mm in relief) to which the amphipods build tubes do provide some protection from Ilyanassa. In soft-sediment benthic communities, such small structures may provide significant refuge for small epifauna and shallow burrowing infauna escaping from small-scale, biogenic disturbance. 相似文献
46.
R Martin DS Buchan JS Baker J Young N Sculthorpe FM Grace 《Biology of sport / Institute of Sport》2015,32(4):307-313
The present study examined the physiological impact of a school based sprint interval training (SIT) intervention in replacement of standard physical education (SPE) class on cardio-respiratory fitness (CRF) and glucose homeostasis during the semester following summer vacation. Participants (n=49) were randomly allocated to either intervention (SIT; n=26, aged 16.9 ± 0.3 yrs) or control group who underwent standard physical education (SPE; n=23, aged 16.8 ± 0.6 yrs). CRF (VO2max) and glucose homeostasis were obtained prior-to and following 7 weeks of SIT exercise. Significant group x time interaction was observed for CRF (P < 0.01) with non-significant trends for fasting insulin (P= 0.08), and HOMA-IR (P=0.06). CRF decreased (P < 0.01) in SPE such that POST intervention CRF was significantly lower (P< 0.05) in SPE. Fasting plasma glucose (P < 0.01), insulin (P< 0.01) and HOMA-IR (P< 0.01) increased significantly amongst SPE. The main finding of the present study is that 7-weeks of SIT exercise is an effective method of maintaining (but not improving) CRF and fasting insulin homeostasis amongst school-going adolescents. SIT exercise demonstrates potential as a time efficient physiological adjunct to standard PE class in order to maintain CRF during the school term. 相似文献
47.
The cDNA cloning and molecular evolution of reptile and pigeon lactate dehydrogenase isozymes 总被引:1,自引:0,他引:1
The cDNAs encoding lactate dehydrogenase isozymes LDH-A (muscle) and LDH-B
(heart) from alligator and turtle and LDH-A, LDH-B, and LDH-C (testis) from
pigeon were cloned and sequenced. The evolutionary relationships among
vertebrate LDH isozymes were analyzed. Contrary to the traditional belief
that the turtle lineage branched off before the divergence between the
lizard/alligator and bird lineages, the turtle lineage was found to be
clustered with either the alligator lineage or the alligator-bird clade,
while the lizard lineage was found to have branched off before the
divergence between the alligator/turtle and bird lineages. The pigeon
testicular LDH-C isozyme was evidently duplicated from LDH-B (heart), so it
is not orthologous to the mammalian testicular LDH-C isozymes.
相似文献
48.
Sacha AFT van Hijum Richard JS Baerends Aldert L Zomer Harma A Karsens Victoria Martin-Requena Oswaldo Trelles Jan Kok Oscar P Kuipers 《BMC bioinformatics》2008,9(1):1-10
Background
Visualising the evolutionary history of a set of sequences is a challenge for molecular phylogenetics. One approach is to use undirected graphs, such as median networks, to visualise phylogenies where reticulate relationships such as recombination or homoplasy are displayed as cycles. Median networks contain binary representations of sequences as nodes, with edges connecting those sequences differing at one character; hypothetical ancestral nodes are invoked to generate a connected network which contains all most parsimonious trees. Quasi-median networks are a generalisation of median networks which are not restricted to binary data, although phylogenetic information contained within the multistate positions can be lost during the preprocessing of data. Where the history of a set of samples contain frequent homoplasies or recombination events quasi-median networks will have a complex topology. Graph reduction or pruning methods have been used to reduce network complexity but some of these methods are inapplicable to datasets in which recombination has occurred and others are procedurally complex and/or result in disconnected networks.Results
We address the problems inherent in construction and reduction of quasi-median networks. We describe a novel method of generating quasi-median networks that uses all characters, both binary and multistate, without imposing an arbitrary ordering of the multistate partitions. We also describe a pruning mechanism which maintains at least one shortest path between observed sequences, displaying the underlying relations between all pairs of sequences while maintaining a connected graph.Conclusion
Application of this approach to 5S rDNA sequence data from sea beet produced a pruned network within which genetic isolation between populations by distance was evident, demonstrating the value of this approach for exploration of evolutionary relationships. 相似文献49.
Functional changes in human leukemic cell line HL-60. A model for myeloid differentiation 总被引:12,自引:0,他引:12 下载免费PDF全文
Polar solvents induce terminal differentiation in the human promyelocytic leukemia cell line HL-60. The present studies describe the functional changes that accompany the morphologic progression from promyelocytes to bands and poly-morphonuclear leukocytes (PMN) over 9 d of culture in 1.3 percent dimethylsulfoxide (DMSO). As the HL-60 cells mature, the rate of O(2-) production increase 18-fold, with a progressive shortening of the lag time required for activation. Hexosemonophosphate shunt activity rises concomitantly. Ingestin of paraffin oil droplets opsonized with complement or Ig increases 10-fold over 9 d in DMSO. Latex ingestion per cell by each morphologic type does not change significantly, but total latex ingestion by groups of cells increases with the rise in the proportion of mature cells with greater ingestion capacities. Degranulation, as measured by release of β-glucuronidase, lysozyme, and peroxidase, reaches maximum after 3-6 d in DMSO, then declines. HL-60 cells contain no detectable lactoferrin, suggesting that their secondary granules are absent or defective. However, they kill staphylococci by day 6 in DMSO. Morphologically immature cells (days 1-3 in DMSO) are capable of O(2-) generation, hexosemonophosphate shunt activity, ingestion, degranulation, and bacterial killing. Maximal performance of each function by cells incubated in DMSO for longer periods of time is 50-100 percent that of normal PMN. DMSO- induced differentiation of HL-60 cells is a promising model for myeloid development. 相似文献
50.
Limulus ventral photoreceptors were voltage clamped to the resting (dark) potential and stimulated by a 20-ms test flash and a 1-s conditioning flash. At a constant level of adaptation, we measured the response to the test flash given in the dark (control) and the incremental response produced when the test flash occurred within the duration of the conditioning flash. The incremental response is defined as the response to the conditioning and test flashes minus the response to the conditioning flash given alone. When the test flash was presented within 100 ms after the onset of the conditioning flash we observed that: (a) for dim conditioning flashes the incremental response equaled the control response; (b) for intermediate intensity conditioning flashes the incremental response was greater than the control response (we refer to this as enhancement); (c) for high intensity conditioning flashes the incremental response nearly equaled the control response. Using 10-μm diam spots of illumnination, we stimulated two spatially separate regions of one photoreceptor. When the test flash and the conditioning flash were presented to the same region, enhancement was present; but when the flashes were applied to separate regions, enhancement was nearly absent. This result indicates that enhancement is localized to the region of illumination. We discuss mechanisms that may account for enhancement. 相似文献