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1.
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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Exhausted T cells and regulatory T (Treg) cells have been recently proposed to be new risk factors for recurrent miscarriage (RM). Intravenous immunoglobulin G (IVIG) treatment reported to modulate various immune cells. In this study, the effects of IVIG on the frequency and function of exhausted T cells, exhausted Tregs, and Treg cells, as well as pregnancy outcome in women with unexplained RM (URM), were investigated. Ninety-four pregnant women with RM were enrolled. At the time of positive pregnancy, blood samples were drawn. Forty-four patients with URM were included as IVIG receiving treated group and received 400 mg/kg of IVIG and the rest fifty patients were considered as a control group and received no IVIG administration. IVIG was given intravenously every 4 weeks during 32 weeks of gestation. Blood samples of patients were collected after the latest administration. Exhausted T cells, exhausted Tregs, and Treg cells were evaluated pre- and posttreatment in both groups. IVIG induced a significant decrease in the frequency of exhausted Tregs population and function as well as a significant increase in Treg cells population, however, IVIG failed to affect population and the function of exhausted T cells. Pregnancy outcome was successful in IVIG treated women (86.3%) and were significantly different (P = 0.0006) in compared with the untreated URM subjects (42%). Therefore, employing of IVIG increases Treg cells and diminishes exhausted Tregs responses in RM patients with cellular immune anomalies throughout the pregnancy. Immunemodulatory effects of IVIG are probably associated with successful pregnancy outcome.  相似文献   
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N(6)-Isopentenyladenosine (iPA), a member of the cytokinin family of plant hormones, exerts remarkable inhibition on tumor cell proliferation and apoptosis in several tumor cell lines. In this study, we report that iPA is able to inhibit the proliferation and promotes apoptosis in HCT-15 human colon cancer cells in a dose-dependent manner with a concentration of 2.5?μM, which causes 50% inhibition of cell viability. The cell cycle analysis by flow cytometry showed that iPA-induced growth arrest could be associated to apoptosis. Moreover, suppression of clonogenic activity occurs after exposure to iPA at a concentration of 2.5?μM for HCT-15.  相似文献   
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We report on the second phase of a programme to select a relative of Arabidopsis thaliana for use in large-scale molecular genetic studies of nickel (Ni) and zinc (Zn) hyperaccumulation. We also report on the relatedness among Thlaspi caerulescens accessions and the utility of using O-acetyl-L-serine as a marker for Ni and Zn hyperaccumulation potential. Twenty-seven new accessions of metal-accumulating species collected in the Czech Republic, France, Greece, Italy, Slovenia and the USA during Spring-Summer 2002 were evaluated. The criteria established for selection were hyperaccumulation of metals (Ni and Zn); compact growth habit; reasonable time to flowering; production of > or = 1000 seeds per plant; self-fertility; compact diploid genome; high sequence similarity to A. thaliana; > or = 0.1% transformation efficiency with easy selection. We conclude that the best candidate identified in the first phase was the best candidate overall: T. caerulescens accession St Félix de Pallières.  相似文献   
5.
In the present study Cervatana and Almagra models from decision support system, MicroLEIS DSS, were applied to segregation of arable land surfaces from the marginal ones and suitability evaluation of wheat (Triticum aestivum), maize (Zea mays) and alfalfa (Medicago sativa) in Souma area with approximately 4100 ha extension in West Azarbaijan. Obtained results from both models are presented and discussed in this research work. Soil morphological and analytical data were collected from 35 soil profiles, representative of the study area and stored in SDBm plus database. The control or vertical section of soil for applying and running the models for annual selected crops, was calculated by soil layer generator 0.0–50 cm in depth, or between the surface and the limit of useful depth when the latter is between 0.0 and 50 cm. According to results, 80.49% of the total area was good capable for agricultural uses and 19.51% must be reforested and not dedicated to agriculture. The lands with good capability for agricultural uses is classified as highly suitable area (S2) for wheat, maize and alfalfa, but results in 822 ha for maize and in 126 ha for alfalfa refers to an excellent suitable (S1) and moderately suitable (S3) classes respectively. The most important limitation factors are soil texture and carbonate alone or together and maize — wheat — alfalfa can be selected as the best crop rotation. A simple map subsystem (ArcView GIS) was used for basic data and models result demonstration on a map.  相似文献   
6.
Selenium (Se), an essential micronutrient, is believed to enhance neutrophil functions. This study aimed to compare the effects of supplemented organic (Sel-Plex®) and inorganic (sodium selenite) Se on neutrophil functions in high-producing dairy cows, during the periparturient period. Twenty-five Holstein cows were randomly allocated to five dietary treatments as follows: control diet (basal diet without Se supplementation), IN 0.3 (basal diet supplemented with inorganic Se at 0.3 mg/kg dry matter (DM)), IN 0.5 (inorganic Se at 0.5 mg/kg DM), OR 0.3 (organic Se at 0.3 mg/kg DM) and OR 0.5 (organic Se at 0.5 mg/kg DM). Some evaluated parameters included neutrophil functions and plasma Se concentrations in cows and plasma Se concentrations in calves. Neutrophil phagocytosis did not significantly differ among the five groups. However, organic Se supplementation significantly increased (P < 0.01) the respiratory burst of neutrophils when compared to cows fed IN 0.3 and the control diet. In comparison to inorganic Se, neutrophil apoptosis was decreased (P < 0.01) when cows were fed organic Se or the control diets. These effects of organic Se on respiratory burst activities and apoptosis of neutrophils were in a dose-dependent manner. Calf plasma Se concentrations were higher (P < 0.05) when cows were fed OR 0.5 and IN 0.5.  相似文献   
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Cumulus contributions during bovine fertilization in vitro   总被引:5,自引:0,他引:5  
A mandatory step in performing micromanipulation techniques, studying sperm-oocyte interactions and evaluating morphological aspects of oocyte quality is the removal of cumulus cells from oocytes or zygotes at various stages. In cattle, cumulus removal shortly before fertilization in vitro strongly decreases sperm penetration rates. This study was conducted to evaluate the function of the cumulus oophorus during bovine fertilization in vitro. The importance of cumulus secretions during IVF was investigated by inseminating cumulus-denuded oocytes (CDOs) in fertilization medium supplemented with individual cumulus secretions, such as progesterone or hyaluronic acid. None of these substances increased the fertilization rate of CDOs. However, fertilizing CDOs in cumulus-conditioned medium or on a cumulus monolayer partially restored the reduction in fertilization rate (P<0.05). The fertilization rate of CDOs inseminated on a cumulus monolayer further increased when physical contact between the gametes and the monolayer was prevented by fertilizing them inside a culture plate insert placed on the monolayer (P<0.05). Finally, the importance of reactive oxygen species (ROS) generation and O(2) concentration during IVF was studied. Luminol-dependent chemiluminescence revealed a higher ROS load in conditioned medium of cumulus-enclosed oocytes (CEOs) than in that of CDOs after sperm-oocyte co-incubation (P<0.05). Furthermore, lowering the external O(2) concentration from 20 to 5% decreased the fertilization rate of both CEOs and CDOs, but had a higher impact on CEOs (P<0.05). In conclusion, this study provides evidence that the cumulus oophorus benefits the fertilizing ability of penetrating spermatozoa by creating a complex microenvironment of both cumulus secretions and metabolic products around the oocyte. Gap junctional communication between the oocyte and corona cells as well as sperm trapping by the cumulus oophorus seem to be essential factors in supporting fertilization.  相似文献   
10.
Understanding the functional connections between genes, proteins, metabolites and mineral ions is one of biology's greatest challenges in the postgenomic era. We describe here the use of mineral nutrient and trace element profiling as a tool to determine the biological significance of connections between a plant's genome and its elemental profile. Using inductively coupled plasma spectroscopy, we quantified 18 elements, including essential macro- and micronutrients and various nonessential elements, in shoots of 6,000 mutagenized M2 Arabidopsis thaliana plants. We isolated 51 mutants with altered elemental profiles. One mutant contains a deletion in FRD3, a gene known to control iron-deficiency responses in A. thaliana. Based on the frequency of elemental profile mutations, we estimate 2-4% of the A. thaliana genome is involved in regulating the plant's nutrient and trace element content. These results demonstrate the utility of elemental profiling as a useful functional genomics tool.  相似文献   
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