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1.
Molecular Biology Reports - Stevia rebaudiana produces sweet steviol glycosides that are 300 times sweeter than sugar and have the beneficial effects on human health including anti-hyperglycaemic....  相似文献   
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Crystals of an ATPase fragment of bovine clathrin uncoating ATPase   总被引:1,自引:0,他引:1  
A 44,000 Mr amino-terminal, clathrin-independent ATPase fragment of the bovine clathrin uncoating ATPase has been crystallized in a form suitable for X-ray diffraction studies. The crystals are orthorhombic, space group P2(1)2(1)2(1), a = 145.3 A, b = 65.0 A, c = 46.9 A, with one protein molecule per asymmetric unit (1 A = 0.1 nm).  相似文献   
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Patterns of sequence variation in the mitochondrial D-loop region of shrews   总被引:8,自引:2,他引:6  
Direct sequencing of the mitochondrial displacement loop (D-loop) of shrews (genus Sorex) for the region between the tRNA(Pro) and the conserved sequence block-F revealed variable numbers of 79-bp tandem repeats. These repeats were found in all 19 individuals sequenced, representing three subspecies and one closely related species of the masked shrew group (Sorex cinereus cinereus, S. c. miscix, S. c. acadicus, and S. haydeni) and an outgroup, the pygmy shrew (S. hoyi). Each specimen also possessed an adjacent 76-bp imperfect copy of the tandem repeats. One individual was heteroplasmic for length variants consisting of five and seven copies of the 79-bp tandem repeat. The sequence of the repeats is conducive to the formation of secondary structure. A termination-associated sequence is present in each of the repeats and in a unique sequence region 5' to the tandem array as well. Mean genetic distance between the masked shrew taxa and the pygmy shrew was calculated separately for the unique sequence region, one of the tandem repeats, the imperfect repeat, and these three regions combined. The unique sequence region evolved more rapidly than the tandem repeats or the imperfect repeat. The small genetic distance between pairs of tandem repeats within an individual is consistent with a model of concerted evolution. Repeats are apparently duplicated and lost at a high rate, which tends to homogenize the tandem array. The rate of D- loop sequence divergence between the masked and pygmy shrews is estimated to be 15%-20%/Myr, the highest rate observed in D-loops of mammals. Rapid sequence evolution in shrews may be due either to their high metabolic rate and short generation time or to the presence of variable numbers of tandem repeats.   相似文献   
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大鼠胼胝体内神经肽Y免疫反应阳性纤维的发育   总被引:1,自引:0,他引:1  
本实验用免疫组织化学ABC法研究了大鼠胼胝体内神经肽Y免疫反应阳性(NPY-IR)纤维的生后发育。结果发现,许多NPY-IR纤维在大鼠出生时便存在于胼胝体内。NPY-IR胼胝体纤维的密度在生后1周内继续逐渐增高,在第2周内达到最高峰。之后,NPY-IR胼胝体纤维的密度逐渐下降,至第3周末时接近成年时的水平,即仅有少量NPY-IR纤维存在于胼胝体内。这些结果提示在大鼠早期生后发育过程中许多NPY-IR胼胝体纤维是暂时性的,其作用可能与大脑皮质的机能发育有关。  相似文献   
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International Journal of Peptide Research and Therapeutics - Infections with HCV, HBV and poliovirus are still considered to be substantial global health burdens. Vaccination is one of the most...  相似文献   
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Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a non-invasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory substitution.In this study,22 healthy participants took part besides 5 amputee participants.The duration time of the study was 31 days with five test steps according to the Leitner technique.An adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to participants.Also,to isolate the surround-ings and show colors,a Virtual Reality(VR)glass was employed.The statistical results conducted are based on the response of participants with questionnaire method.Using Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the"Repeated Measures ANOVA",it is noticed that the time of numbness felt by participants had significant(P value<0.001)difference.Participants could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object's temperature with only once time experimenting the color temperature.  相似文献   
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A novel affinity biosensor is proposed based on the hybrid plasmonic platform. The proposed biosensor benefits from the high sensitivity of the surface plasmon resonance (SPR), while at the same time, it is capable of performing measurements in both the TM and TE polarizations (p- and s-polarizations). Unlike the conventional SPR biosensors, the polarization diversity of the hybrid sensor allows for decoupling of the bulk index variations in the fluidic channels (due to variations in concentration, decomposition, temperature, and so on) from the surface properties of the attached molecules. Compatibility of the proposed hybrid plasmonic biosensor with standard Si-processing techniques and the simplicity of its design are other advantages of the sensor which makes its fabrication straightforward. The best figure of merit for the biosensor is defined based on the minimum detection limit and a genetic algorithm is used to optimize the device. A method of de-convolving the surface and bulk effects is also discussed.  相似文献   
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