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91.
Using oriented Gabor patches, we found that for nearly cardinal target orientations, oblique flankers' orientations induced more interference than did cardinal flankers' orientations. This pattern was observed both at the local and global levels of flankers' orientation. With respect to the global orientation (flankers' global arrangement around the target), there was no difference between the effects of the two cardinal orientations, and both induced the same amount of interference. With respect to the local orientation (Gabors' orientation), in accordance with previous reports, a difference was found between the effects of the two cardinal orientations--a considerable amount of interference with flankers equal in orientation to the target (although less than with the oblique flankers) and almost no interference from flankers orthogonal to the target. Crowding was also affected by an anisotropy based on the target-fixation axis (radial, tangential, and diagonal) and by the flankers' relations. The magnitude of these latter factors was small relative to that of the former ones. The multiple factors that affected crowding, as well as the similarities and the differences between the effects at the two orientation levels, suggest that crowding is determined by multiple sources of interference operating at several levels of representation. 相似文献
92.
Shallu Tomer Yogesh K Chawla Ajay Duseja Sunil K Arora 《World journal of gastroenterology : WJG》2016,22(22):5173-5182
AIM: To elucidate the molecular mechanisms leading to development of functionally impaired dendritic cells(DCs) in chronic hepatitis C(CHC) patients infected with genotype 3 virus.METHODS: This prospective study was conducted on the cohorts of CHC individuals identified as responders or non-responders to antiviral therapy. Myeloid DCs were isolated from the peripheral blood of each subject using CD1c(BDCA1)+ DC isolation Kit. Monocytes from healthy donor were cultured with DC growth factors such as IL-4 and GM-CSF either in the presence or absence of hepatitis C virus(HCV) viral proteins followed by LPS stimulation. Phenotyping was done by flowcytometry and gene expression profiling was evaluated by real-time PCR.RESULTS: Non-responders [sustained virological response(SVR)-ve] to conventional antiviral therapy had significantly higher expression of genes associated with interferon responsive element such as IDO1 and PD-L1(6-fold) and negative regulators of JAK-STAT pathway such as SOCS(6-fold) as compared to responders(SVR+ve) to antiviral therapy. The downregulated genes in non-responders included factors involved in antigen processing and presentation mainly belonging to major histocompatibility complex(MHC) Class-Ⅱ family as HLA-DP, HLA-DQ(2-fold) and superoxide dismutase(2-fold). Cells grown in the presence of HCV viral proteins had genes downregulated for factors involved in innate response, interferon signaling, DC maturation and co-stimulatory signaling to T-cells, while the genes for cytokine signaling and Toll-like receptors(4-fold) were upregulated as compared to cells grown in absence of viral proteins.CONCLUSION: Underexpressed MHC class-Ⅱ genes and upregulated negative regulators in non-responders indicate diminished capacity to present antigen and may constitute mechanism of functionally defective state of DCs. 相似文献
93.
94.
Five drug-models, 4-parahydroxybenzoic acid (4HBA), methyl (MBA), propyl (PBA) and butyl (BBA) paraben and propyl gallate (PG), all of similar chemical nature, were mixed in different proportions (50-73.7%) with microcrystalline cellulose (MCC) (26.3-50%) plus various levels of water (26.9-50.0%). The wet powder mass was extruded and spheronized under standard conditions. The pellets produced were evaluated in terms of their median diameter, their modal size range, the % within a given size range (0.7-1.7 mm) and their shape factor. For the majority of formulations, all drug models, except 4HBA, produced pellets. This material only had two combinations of excipients that produced acceptable pellets. For all the model drugs, two combinations of formulations could be identified; (1) a combination, which produced pellets from all the model drugs and (2) a combination, which was too wet to produce pellets with any of the model drugs. Between these two extremes, whether pellets could be made and their quality varied with the model drug. Cluster analysis was able to divide the formulations into 4 clusters. In cluster 1 all the model drugs produced pellets except 4HBA; in cluster 2 all drugs produced pellets except MBA; in cluster3, pellets were produced with PBA, BBA and PG while MBA produced agglomerates and 4HBA was too dry; in cluster 4, MBA and BBA produced pellets, PBA produced agglomerates while 4HBA was too dry to pelletise and PG too dry to extrude. The five drug models showed different relationships between the median pellet size and drug-load and initial water content in the formulation. Cluster analysis indicated that, the level of water and type of model drug were the most significant factors in determining the pellet size. Three clusters could be identified, but the response to water content was drug dependent. It was not possible to identify a relationship between the force required to extrude the wet mass and the ability to produce good pellets nor their median size. All the products, which could be classified as good pellets, when produced, had a shape factor that can be considered to be indicative of a spherical shape. The most consistent material, in terms of spheronization, as represented by median diameter, size range and roundness, was propyl gallate (PG), which throughout all the formulations produced an almost constant value for shape factor and median pellet size, which in the majority of cases fell within a limited pellet size. 相似文献
95.
96.
Characterization of a calcium-activated chloride channel as a shared target of Th2 cytokine pathways and its potential involvement in asthma. 总被引:12,自引:0,他引:12
Y Zhou Q Dong J Louahed C Dragwa D Savio M Huang C Weiss Y Tomer M P McLane N C Nicolaides R C Levitt 《American journal of respiratory cell and molecular biology》2001,25(4):486-491
Interleukin (IL)-9 is a T helper (Th) 2 cytokine recently implicated as an essential factor in determining susceptibility to asthma. Transgenic mice overexpressing IL-9 exhibit many features that are characteristic of human asthma. To better understand the mechanism by which IL-9 mediates the various biologic activities in asthma, we performed suppressive subtraction hybridization with whole lung from IL-9 transgenic and control mice. Here we report the identification of mCLCA3, a calcium-activated chloride channel that was specifically induced in the lung epithelium of IL-9 transgenic mice. Expression of mCLCA3 could also be induced by intratracheal administration of IL-9 or other Th2 cytokines (IL-4, IL-13), but not by interferon-gamma. Moreover, expression of mCLCA3 was induced in the lung of antigen-exposed mice, and this induction could be suppressed by neutralizing IL-9 antibody treatment, indicating IL-9 is both necessary and sufficient to induce mCLCA3 in this experimental model of asthma. Finally, we demonstrate that hCLCA1 is the human counterpart to mCLCA3 and is also induced in vitro in human primary lung cells by Th2 cytokine treatment. Together, these data strongly implicate the involvement of mCLCA3 (in mice) and hCLCA1 (in humans) in the pathogenesis of Th2 cytokine-mediated asthmatic disorders. 相似文献
97.
A recent study has demonstrated that the mere organization of some elements in the visual field into an object attracts attention automatically [Kimchi, R., Yeshurun, Y., & Cohen-Savransky, A. (2007). Automatic, stimulus-driven attentional capture by objecthood. Psychonomic Bulletin & Review, 14(1), 166-172]. We tested whether similar results will emerge when the target is not a part of the object and with simplified task demands. A matrix of 16 black L elements in various orientations preceded the presentation of a Vernier target. The target was either added to the matrix (Experiment 1), or appeared after its offset (Experiment 2). On some trials four elements formed a square-like object, and on some of these trials the target appeared in the center of the object. No featural uniqueness or abrupt onset was associated with the object and it did not predict the target location or the direction of the target’s horizontal offset. Performance was better when the target appeared in the center of the object than in a different location than the object, even when the target appeared after the matrix offset. These findings support the hypothesis that a perceptual object captures attention (Kimchi et al., 2007), and demonstrate that this automatic deployment of attention to the object is robust and involves a spatial component. 相似文献
98.
Cooks T Arazi L Schmidt M Marshak G Kelson I Keisari Y 《International journal of cancer. Journal international du cancer》2008,122(7):1657-1664
In the present study, we examined the antitumoral effects caused by the release of alpha emitting radioisotopes into solid squamous cell carcinoma (SCC) tumors. Using a novel method termed DART (Diffusing Alpha-emitters Radiation Therapy), we assessed the efficacy of short-lived daughters of (224)Ra releasing alpha particles, dispersing in the malignant tissue, to cause tumor growth retardation and destruction. It was carried out using specially designed wires loaded with (224)Ra activities in the range of 7-42 kBq in a set of experiments performed on BALB/c and nude mice bearing metastatic SCC tumors derived from either mouse SQ2 or human CAL27 cell lines. The insertion of a DART wire to the center of 6-7 mm primary tumors, retarded tumor growth, reduced lung metastatic load, prolonged life expectancy and in some cases caused tumor eradication. These effects were enhanced either when treating smaller tumors or treating identical tumors with 2 DART wires. Similar experiments on human-derived SCC tumors in nude mice were consistent with the outcomes of the murine model. Histological assessments revealed the tissue damage pattern, and indicated a role for the tumor vasculature in the dispersion of the atoms and the propagation of the damage. Our findings indicate that Diffusing Alpha-emitting Radiation Therapy is effective in a model system using SCC primary tumors. The in situ destruction of primary solid tumors by DART is evidently a necessary step toward curing cancer and might be augmented by chemotherapy and other modalities such as immunotherapy or antigrowth factors agents. 相似文献
99.
Feigenberg T Ben-Shushan A Daka K Klein BY Bloom RA Rojansky N 《The Journal of reproductive medicine》2008,53(4):287-293
OBJECTIVE: To study whether osteopenia occurs following pregnancy and to evaluate its severity in young primiparas. STUDY DESIGN: A prospective case control study. Sixty-one young primigravidae early after birth and 59 nulligravidae matched for age and BMI participated in the study. Bone status was examined using ultrasonic bone transmission velocity over the tibia; Z-score and T-score for bone density were calculated. Serum bone alkaline phosphatase, osteocalcin and urinary N-telopeptide crosslinks were evaluated as bone remodeling biochemical markers. RESULTS: Ultrasonic parameters of bone status following delivery were significantly lower in the puerperal group as compared to the nulligravida group. Serum mean bone alkaline phosphatase levels and urinary N-telopeptide crosslinks secretion were higher by 50% in the puerperal group, while serum osteocalcin levels were significantly lower (by 25%) than in the nulligravida controls. A positive correlation between ultrasonic measurements and biochemical markers was demonstrated in the postpartum group, whereas the control group showed a negative correlation. CONCLUSION: Women at their early puerperium demonstrate a significant cortical bone mass reduction as measured by ultrasonograph and markers of bone turnover. It appears that pregnancy is a state of unbalanced accelerated bone turnover that may be associated with reduced osteoblastic activity. 相似文献
100.
Yaron Arbel Yacov Shacham Ariel Finkelstein Amir Halkin Assi Milwidsky Shlomo Berliner Tomer Ziv-Baran Miri Revivo Itzhak Herz Gad Keren Shmuel Banai 《Thrombosis research》2014