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41.
随着嵌入式WinCE系统的发展和近距离无线通信的广泛使用,有必要为近距离无线通信芯片编写驱动。由于nRF24L01在WinCE系统下驱动的缺乏,使得WinCE与nRF24L01芯片之间的直接通信成为困难。本文的驱动设计正好解决了这一难题。 相似文献
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Asmaa A. Zidan Mohammed Al-Hawwas Griffith B. Perkins Ghada M. Mourad Catherine J. M. Stapledon Larisa Bobrovskaya Xin-Fu Zhou Plinio R. Hurtado 《International journal of molecular sciences》2021,22(1)
Elucidation of the biological functions of extracellular vesicles (EVs) and their potential roles in physiological and pathological processes is an expanding field of research. In this study, we characterized USC–derived EVs and studied their capacity to modulate the human immune response in vitro. We found that the USC–derived EVs are a heterogeneous population, ranging in size from that of micro–vesicles (150 nm–1 μm) down to that of exosomes (60–150 nm). Regarding their immunomodulatory functions, we found that upon isolation, the EVs (60–150 nm) induced B cell proliferation and IgM antibody secretion. Analysis of the EV contents unexpectedly revealed the presence of BAFF, APRIL, IL–6, and CD40L, all known to play a central role in B cell stimulation, differentiation, and humoral immunity. In regard to their effect on T cell functions, they resembled the function of mesenchymal stem cell (MSC)–derived EVs previously described, suppressing T cell response to activation. The finding that USC–derived EVs transport a potent bioactive cargo opens the door to a novel therapeutic avenue for boosting B cell responses in immunodeficiency or cancer. 相似文献
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Farrukh Aqil Jeyaprakash Jeyabalan Radha Munagala Iqbal Ahmad David J. Schultz Ramesh C. Gupta 《International journal of molecular sciences》2021,22(12)
Breast cancer (BC) is a leading cause of cancer deaths in women in less developed countries and the second leading cause of cancer death in women in the U.S. In this study, we report the inhibition of E2-mediated mammary tumorigenesis by Cuminum cyminum (cumin) administered via the diet as cumin powder, as well as dried ethanolic extract. Groups of female ACI rats were given either an AIN-93M diet or a diet supplemented with cumin powder (5% and 7.5%, w/w) or dried ethanolic cumin extract (1%, w/w), and then challenged with subcutaneous E2 silastic implants (1.2 cm; 9 mg). The first appearance of a palpable mammary tumor was significantly delayed by both the cumin powder and extract. At the end of the study, the tumor incidence was 96% in the control group, whereas only 55% and 45% animals had palpable tumors in the cumin powder and extract groups, respectively. Significant reductions in tumor volume (660 ± 122 vs. 138 ± 49 and 75 ± 46 mm3) and tumor multiplicity (4.21 ± 0.43 vs. 1.16 ± 0.26 and 0.9 ± 0.29 tumors/animal) were also observed by the cumin powder and cumin extract groups, respectively. The cumin powder diet intervention dose- and time-dependently offset E2-related pituitary growth, and reduced the levels of circulating prolactin and the levels of PCNA in the mammary tissues. Mechanistically, the cumin powder diet resulted in a significant reversal of E2-associated modulation in ERα, CYP1A1 and CYP1B1. Further, the cumin powder diet reversed the expression levels of miRNAs (miR-182, miR-375, miR-127 and miR-206) that were highly modulated by E2 treatment. We analyzed the composition of the extract by GC/MS and established cymene and cuminaldehyde as major components, and further detected no signs of gross or systemic toxicity. Thus, cumin bioactives can significantly delay and prevent E2-mediated mammary tumorigenesis in a safe and effective manner, and warrant continued efforts to develop these clinically translatable spice bioactives as chemopreventives and therapeutics against BC. 相似文献
46.
Luciana M. Rodriguez María B. Fernández Ethel E. Pérez Guillermo H. Crapiste 《European Journal of Lipid Science and Technology》2021,123(1):2000132
The main goal of this work is to evaluate the extraction of sunflower oil from enzyme-treated collets using ethanol and isopropanol (IPA) as solvents. The sunflower collets are pretreated with the multienzyme complex Viscozyme L prior to solvent extraction by the Soxhlet method. The influence of the moisture content of the collets, pretreatment, processing time, and solvent type on the amount of total extracted material and the oil extraction efficiency is studied. Some quality parameters such as phospholipid content of the oil and chlorogenic acid content of the residual meal are also analyzed. At low moisture content (7%) the solvents exhibit similar oil extraction ability (98–99%), but with increasing moisture the extraction efficiency of ethanol decreases to about 85%, while no significant differences are observed for IPA. The enzymatic treatment increases the extraction efficiency for all times, especially for ethanol. It is observed that IPA is more efficient in the extraction compared to ethanol, and the amount of nonlipid material is reduced by ≈70%. In addition, the oil extracted with IPA have lower phospholipid content and the residual meal presents a higher chlorogenic acid content. Practical Applications:This work would contribute toward the use of green solvents in the extraction of sunflower oil from collets. Ethanol and isopropanol, used as solvents, present attractive advantages, including low toxicity, good operational security, as well as being obtained from a renewable source. The obtained data provide up-to-date information on the use of these alcohols in the extraction of sunflower oil from collets and the influence of operating conditions, such as moisture content, enzymatic pretreatment of the collets, and the extraction time. Information about oil and meal quality is also reported. 相似文献
47.
Many isotopic techniques can be applied to determine the relative immediate and residual effectiveness of P fertilizers. Using isotopes as tracers, the percentage of utilization by plants of the P derived from a fertilizer can be determined. However this is only possible during the three or four months after the application. Therefore, the P fertilizers may be classified only according to their relative immediate effectiveness. To also evaluate residual effect, which can be observed when more P is applied than is removed with harvest, isotopes of phosphorus can be used. This residual effect is determined by comparing pool sizes of bioavailable soil P in soils with and without P fertilizer aged in soil. The bioavailable soil P pool may be analyzed according to three isotopic experimental procedures which give access to either the A value, or the E value or the L value. The aims, the similarities and the differences between these three procedures, are examined. Some of the theoretical and practical constraints of each method are described in this paper; they must be followed in order to obtain reliable information for agronomic purposes. A method involves measuring the rate of isotopic exchange of phosphate ions in soil-solution systems maintained in steady-state. It is now possible to predict the effectiveness of P fertilizers, whatever their chemical form when this method is applied on soil samples where P fertilizers were applied.This paper was originally submitted as part of the special issue on Evaluation of the Agronomic Effectiveness of Phosphate Fertilizers through the use of Nuclear Related Techniques edited by F. Zapata 相似文献
48.
大型管磨机启停时电压会波动,常规方法是采用一台液体电阻启动器来保证电机启动过程平滑、无冲击。而在小电网下,此法却不尽人意。在越南某水泥粉磨站的水泥磨主电机的供电系统中,成功地将I.L.B装置与液体电阻启动器结合起来,收到事半功倍的效果。 相似文献
49.
超低碳不锈钢316L管-管板的焊接采用手工钨极氩弧焊,对316L不锈钢的焊接性进行了分析和研究,通过工艺试验,证明了焊接工艺的可靠性,并在不锈钢浓H2SO4冷却器阳极保护(管壳式)设备的焊接中取得了满意的效果. 相似文献
50.
W. D. Branch T. Nakayama M. S. Chinnan 《Journal of the American Oil Chemists' Society》1990,67(9):591-593
Fatty acid composition was determined among seven U.S. runner-type peanut (Arachis hypogaea L.) cultivars: Florunner, Sunrunner, GK-7, Southern Runner, Sunbelt Runner, Okrun, and Langley. Significant year and cultivar
differences were found within these fatty acid profiles. Southern Runner had the best oleic to linoleic ratio and iodine values;
whereas Florunner, Sunrunner, and Langley were the highest in unsaturated and lowest in saturated and long-chain fatty acids.
For the future, breeding programs need to continue developing peanut cultivars with improved oil quality. 相似文献