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21.
Johnson AL Ratajczak C Haugen MJ Liu HK Woods DC 《Reproduction (Cambridge, England)》2007,133(3):609-616
Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) represents one of several cytokine members of the tumor necrosis factor superfamily reported to initiate apoptosis in a wide range of transformed, but not most normal, cell types. The present studies were conducted to evaluate the potential for TRAIL to promote apoptotic cell death in differentiated granulosa cells collected from hen preovulatory follicles. While mRNA encoding critical components (including TRAIL) required for a functional extrinsic cell death pathway are expressed in granulosa cells, TRAIL treatment by itself fails to induce either caspase-3 activity or a decrease in cell viability. On the other hand, preculture of cells with the conventional chemotherapeutic, cisplatin, or the 20S proteosome inhibitor, Z-LLF-CHO, sensitizes granulosa cells to TRAIL as evidenced by enhanced caspase-3 activity after 4 h of culture and loss of cell viability after 24 h when compared with either cisplatin or Z-LLF-CHO treatment alone. Moreover, the sensitizing effect of Z-LLF-CHO on TRAIL-induced loss of cell viability is prevented by the selective caspase-8 inhibitor, Z-IETD-FMK. Interestingly, TRAIL mRNA expression is elevated both in prehierarchal follicles undergoing spontaneous atresia and in prehierarchal follicles induced to undergo atresia for 6 h in vitro. In summary, the data demonstrate the presence of a functional TRAIL signaling pathway in hen granulosa cells, and are consistent with the possibility that TRAIL signaling may directly or indirectly participate in the process of follicle atresia in vivo. 相似文献
22.
We report a case in which traumatic scleral tissue loss was surgically treated by a synthetic patch used in neurosurgical procedures. In the present case the patch served as a permanent solution to scleral loss. The patch is available commercially and easily stored. In the light of our experience, we suggest that this patch material be considered for both urgent and semi-elective scleral patching procedures. 相似文献
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Dov Dori Somwang Thipphayathetthana 《International Journal of Satellite Communications and Networking》2016,34(2):295-319
Three persistent common problems in satellite ground control software are obsolescence, lack of desired features and flexibilities, and endless software bug fixing. The obsolescence problem occurs when computer and ground equipment hardware become obsolete, usually after only one‐third into the satellite mission lifetime. The software needs to be updated to accommodate changes on the hardware side, requiring significant work of satellite operators to test, verify, and validate these software updates. Trying to help solve these problems, we have proposed an object‐process methodology model and guidelines for developing satellite ground control software. The system makes use of a database‐driven application and concepts of object‐process orientation and modularity. In the new proposed framework, instead of coding each software function separately, the common base functions will be coded, and combining them in various ways will provide the different required functions. The formation and combination of these base functions will be governed by the main code, definitions, and database parameters. These design principles will make sure that the new software framework would provide satellite operators with the flexibility to create new features and enable software developer to find bugs quicker and fix them more effectively. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
26.
Metacognition, or ′thinking about thinking′, can improve scientific literacy and practices. It involves knowledge of cognition, i. e., being cognisant of one‘s knowledge, and regulation of cognition, i. e., consciously controlling the process of knowledge acquisition. A self‐regulated learner can assimilate new knowledge, conduct inquiry, solve problems and plan ahead his or her learning. While studies have been conducted on metacognition in chemistry education, none have included detailed assignments covering a range of metacognitive strategies. Our review of studies on metacognition in chemistry secondary and higher education also includes also several exemplary assignments on the energy topic for facilitating and assessing metacognition in high school classrooms. We use metacognitive prompts and the construct of chemistry understanding levels, macroscopic, microscopic, symbol, and process, as an approach for metacognitive intervention. Finally, we provide recommendations for educators and a rubric for researchers. 相似文献
27.
Negotiating Norms of Discussion in the Public Arena: The Use of Irony in Israeli Political Radio Phone‐In Programs
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Phone‐in radio programs are part of the public sphere and thus require open access, rationality, and practicality. Simultaneously, they are a media product, which requires entertaining content. We demonstrate these demands through the analysis of interactional irony in Israeli political radio phone‐ins. From an emic perspective, callers see irony as detrimental to the discussions, yet hosts and regular callers use it to make entertaining interactions. Irony is a critical tool that points to violations of norms: the norm of a clear 2‐sided interaction; norms akin to the Habermasian public sphere; and at the content level, irony is used to reject racist positions. Being indirect, irony can be used to create an entertaining yet critical discussion in the public sphere. 相似文献
28.
Dori L. Severi M. Impronta M. Sun J.Y.-C. Arienzo M. 《Electron Devices, IEEE Transactions on》1990,37(1):177-182
Charge trapping and interface-state generation in very thin nitride/oxide (4-nm Si3N4+8-nm SiO2) composite gate insulators are studied as a function of gate electrode work function and bottom oxide thickness. The behavior of the trapped positive charge under bias-temperature stress after avalanche electron injection (AEI) is investigated. Evidence is presented that secondary hole injection from the anode (gate/Si3N4 interface) and subsequent trapping near the SiO2-Si interface result in a turnaround of the flatband voltage shift during AEI from the substrate. Just like the thermal oxides on Si, slow-state generation near the SiO2-Si interface and boron acceptor passivation in the surface-space charge layer of the Si substrate are also observed after AEI in these nitride/oxide capacitors, and they are found to be strongly related to the secondary hole injection and trapping. Finally, interface-state generation can take place with little secondary anode hole injection and is enhanced by the occurrence of hole trapping 相似文献
29.
The authors describe two cases of premacular hemorrhage secondary to retinal macroaneurysm, with significant loss of vision. A few low-energy bursts of ND:YAG laser were applied to perforate the anterior surface of the hemorrhage, subsequently draining the blood into the vitreous cavity. The blood gradually cleared from the vitreous, with restoration of good vision. Nd:YAG laser seems to be a safe and efficient method for treating premacular hemorrhage and should be considered as a therapeutic option. 相似文献
30.
Use of different sensing materials and deposition techniques for thin-film sensors to increase sensitivity and selectivity 总被引:1,自引:0,他引:1
The performances of metal oxide semiconducting materials used as gas-sensing detectors depend strongly on their structural and morphological properties. The average grain size has been proved to play a prominent role and better sensor performances were found in polycrystalline films where the grain size is few tens of nm or smaller. On the other hand, thermal treatments during thin-film deposition and/or sample postprocessing could lead to a grain coalescence, thus decreasing the conductivity of the sensing film. Avoiding such a phenomenon, still keeping optimized processing conditions, will increase the sensor performances, maintaining the resistivity at acceptable values. In this work, new gas-sensing materials and new thin-film deposition procedures have been investigated. Aiming to preserve the sensitivity, to enhance selectivity and to reduce the drift, thin films of WO/sub 3/ and CrTiO/sub 3/ deposited by pulsed-laser ablation (PLA) and of SnO/sub 2/ deposited by rheotaxial growth and thermal oxidation techniques were comparatively characterized. Three issues were mainly addressed: the variation of the conductivity as a function of RH, the sensitivity toward benzene, CO, acetone, and NO/sub 2/, and the selectivity. 相似文献