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51.
BackgroundNon Hodgkin lymphoma (NHL) is one of the immune system cancers. The occurrence and progression of malignant lymphomas depends on cellular pathways deregulation. Understanding the relationship between the immune system at the genetic level and malignant transformation is critical to reach its etiology.ObjectiveThe aim of this work is to evaluate the expression of five immune related genes (PD-1, FOXP3, GrA, GrB and CD11c) in patients with diffuse large B cell non Hodgkin lymphoma (DLBCL).Materials and methodsThis study was conducted on fifty patients with DLBCL and fifty sex and age matched apparently healthy subjects. The participants were subjected to these laboratory investigations: complete blood count, serum lactate dehydrogenase and β2microglobulin (β2M) levels and determination of PD-1, FOXP3, GrA, GrB and CD11c gene expressions.ResultsThe results of this study revealed that PD-1, FOXP3, GrA, GrB and CD11c gene expressions were significantly increased in DLBCL patients.ConclusionPatients with DLBCL have variablePD-1, FOXP3,GrA, GrB and CD11cgene expressions levels, which are correlated with the overall survival (OS) indicating that they can be good predictors of outcome in these patients.  相似文献   
52.
BackgroundMyocardial infarction (MI) is the major cause of death and disability worldwide. Many recent studies revealed the relationship between circulating irisin levels, endothelial dysfunctions and subclinical atherosclerosis in adult patients.ObjectivesThe aim of this study was to investigate the distribution of Irisin gene single nucleotide polymorphism in patients with MI and its association with other clinical and laboratory variables in these patients.Patients and methodsThis study was carried out in 100 patients with MI, and 100 healthy subjects served as controls. All studied subjects underwent laboratory investigations, including measurement of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-c) high-density lipoprotein cholesterol (HDL-c), creatinine kinase-MB (CK-MB), troponin I (TnI) and genotyping of rs 3480 and rs726344 of Irisin genes using the TaqMan Allelic Discrimination assay technique.ResultsThere was a significant difference of Irisin genotypes in patients when compared to controls. By estimating odd ratio (OR) an association was found between G allele of rs 3480 and A allele of rs726344with increase the risk of developing myocardial infarction by 4.03 and 3.47 fold respectively. GG of rs 3480 carriers had significantly increased Troponin I and triglyceride levels, while GA carriers of rs726344 had significantly increased CKMB, Total cholesterol, LDLc, HDLc, troponin I and triglyceride levels compared with other genotypes.ConclusionG allele of rs 3480 and A allele of rs726344can considered as genetic risk factors for MI; these findings could have an impact on preventive strategy for myocardial infarction.  相似文献   
53.

Background  

The chicken genome contains a BBP-A gene showing similar characteristics to avidin family genes. In a previous study we reported that the BBP-A gene may encode a biotin-binding protein due to the high sequence similarity with chicken avidin, especially at regions encoding residues known to be located at the ligand-binding site of avidin.  相似文献   
54.

Background  

Voice disorders affect patients profoundly, and acoustic tools can potentially measure voice function objectively. Disordered sustained vowels exhibit wide-ranging phenomena, from nearly periodic to highly complex, aperiodic vibrations, and increased "breathiness". Modelling and surrogate data studies have shown significant nonlinear and non-Gaussian random properties in these sounds. Nonetheless, existing tools are limited to analysing voices displaying near periodicity, and do not account for this inherent biophysical nonlinearity and non-Gaussian randomness, often using linear signal processing methods insensitive to these properties. They do not directly measure the two main biophysical symptoms of disorder: complex nonlinear aperiodicity, and turbulent, aeroacoustic, non-Gaussian randomness. Often these tools cannot be applied to more severe disordered voices, limiting their clinical usefulness.  相似文献   
55.
Field use of surface plasmon resonance (SPR) biosensors for environmental and defense applications such as detection and identification of biological warfare agents has been hampered by lack of rugged, portable, high-performance instrumentation. To meet this need, we have developed compact multi-analyte SPR instruments based on Texas Instruments' Spreeta sensing chips. The instruments weigh 3 kg and are built into clamshell enclosures measuring 28 cm x 22 cm x 13 cm. Functions are divided between an electronics unit in the base of the box and a fluidics assembly in the lid. Automated valves and pumps implement an injection loop flow system that allows sensors to be exposed to sample, rinsed, and treated with additional reagents (such as secondary antibodies) under computer control. Injected samples flow over the surfaces of eight sensor chips fastened into a temperature-controlled silicone flowcell. Each chip has 3 sensing regions, for a total detection of 24 areas that can be simultaneously monitored by SPR. Coating these areas with appropriate antibodies or other receptors allows a sample to be screened for up to 24 different substances simultaneously. The instruments report refractive index (RI) values every second, with a typical noise level of 1-3 x 10(-6) RI units. The design of the device is described, and performance is illustrated with detection of six distinct analytes ranging from small molecules to whole microbes during the course of a single experiment.  相似文献   
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57.
Abstract. Adults of different species of the genus Papilio can easily be mated by hand-pairing. The data on egg hatchability, adult formation and F1 fertility in these interspecific hybrids show notable variations according to the crosses. Using these data, values of a differentiation index for each cross were calculated. These estimates of genetic distance were then used to study the phylo-genetic relationships of the species involved. The data are consistent with the existence of the following groups, each consisting of closely related species: the black Papilio supergroup, the Papilio memnon group, the P.demoleus group, the P.xuthus group, the P.machaon group, the P.bianor group, the P.glaucus group and the P.troilus group. The phylogenetic relationships revealed by these data generally coincide with the relationships established by classical taxonomy. In cases where there are differences of opinion among taxonomists, the writer's data usually support one or other of them.  相似文献   
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59.
Previous studies have shown remarkable rostrocaudal selectivity by regenerating motoneurons to the rat serratus anterior (SA) muscle after freezing, crushing, or sectioning the long thoracic (LT) nerve. The LT nerve contains motoneurons from both the sixth and seventh cervical spinal nerves (C6 and C7), with C6 motoneurons as the major source of innervation throughout the muscle, and with C7 motoneurons innervating a larger percentage of muscle fibers caudally than rostrally. To determine if synaptic competition can play a role in neuromuscular topography, both the LT nerve and the branch carrying C6 (rostral) motoneurons to the LT nerve were crushed in newborn rats. This approach provides a temporal advantage to regenerating C7 (caudal) motoneurons. After an initial period during which C7 motoneurons reinnervated a larger proportion of muscle fibers than normal in all SA muscle sectors, C6 motoneurons regained their original proportion of rostral muscle fibers. Caudally, however, C7 motoneurons maintained an expanded territory. With this two-site crush method, the number of C6 motoneurons that reinnervate the SA muscle was significantly decreased from normal, whereas the number of C7 motoneurons remained the same. It is concluded that when C7 motoneurons are given a temporal advantage, synaptic specificity can be altered transiently in rostral muscle sectors and permanently in caudal sectors, and this is correlated with a disproportionate loss of C6 motoneurons. Moreover, this may be an important model for studies of synaptic competition, where terminals destined to be eliminated can be identified beforehand. © 1995 John Wiley & Sons, Inc.  相似文献   
60.
Mitochondrial mismatch analysis is insensitive to the mutational process   总被引:13,自引:4,他引:9  
Mismatch distributions are histograms showing the pattern of nucleotide (or restriction) site differences between pairs of individuals in a sample. They can be used to test hypotheses about the history of population size and subdivision (if selective neutrality is assumed) or about selection (if a constant population size is assumed). Previous work has assumed that mutations never strike the same site twice, an assumption that is called the model of infinite sites. Fortunately, the results are surprisingly robust even when this assumption is violated. We show here that (1) confidence regions inferred using the infinite- sites model differ little from those inferred using a model of finite sites with uniform site-specific mutation rates, and (2) even when site- specific mutation rates follow a gamma distribution, confidence regions are little changed until the gamma shape parameter falls well below its plausible range, to roughly 0.01. In addition, we evaluate and reject the proposition that mismatch waves are produced by pooling data from several subdivisions of a structured population.   相似文献   
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