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排序方式: 共有273条查询结果,搜索用时 15 毫秒
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The influence of socioeconomic and nutritional status on menarche in Nigerian school girls 总被引:1,自引:0,他引:1
EA Abioye-Kuteyi EO Ojofeitimi OI Aina F Kio Y Aluko O Mosuro 《Canadian Metallurgical Quarterly》1997,11(3):185-195
Two once-daily electroconvulsive shocks (ECS) produced retrograde amnesia in rats trained on a Hebb-Williams maze; Verapamil (12.5 mg/kg, i.p.) or felodipine (10 mg/kg, p.o.) administered half an hour before each ECS attenuated this ECS-induced amnesia. Hence, these drugs may hold promise for the containment of amnesia induced by electroconvulsive therapy (ECT). Speculatively, one or more of several mechanisms may be involved: cerebral vasodilatation, enhancement of cholinergic tone, and inhibition of calcium-mediated impairment of neuronal function. These drugs may also act by attenuating the systolic surge in blood pressure during ECT, thereby decreasing edema due to cerebral hyperperfusion, as well as decreasing the possible transfer of potentially neurotoxic macromolecules through a putative breach in the blood-brain barrier. 相似文献
3.
Homozygous and hemizygous deletions of 9p21 are the earliest and most common genetic alteration in bladder cancer. The identification of two cell cycle regulators, CDKN2 and CDKN2B, that map to the common region of deletion has prompted the hypothesis that they are critical tumor suppressor genes in this malignancy. However, controversy as to whether these genes are the only or even the most important target in bladder cancer oncogenesis remains. To more clearly determine the effect of these 9p21 alterations, we mapped the homozygous deletions and performed a detailed mutational and expression analysis for CDKN2, CDKN2B and a closely linked gene, methylthioadenoside phosphorylase (MTAP), in 16 established bladder cancer cell lines. Nine of the 16 lines exhibit large (30 to > 2000 kb) homozygous deletions on 9p21. All deletions include at least one exon of CDKN2, eight of nine include CDKN2B, and six of nine include MTAP. MTAP function correlates with the genomic deletions. SSCP and sequence analysis does not reveal any inactivating point mutations of CDKN2 or of CDKN2B in any of the cell lines without homozygous deletions, and all express the CDKN2 and the CDKN2B mRNA as well as the encoded p16 protein. The p16 protein levels vary widely and are correlated with absent pRb expression. We conclude that the 9p21 deletions in bladder cancer usually inactivate the CDKN2. CDKN2B, and MTAP genes but that CDKN2 is the most common target. Other mechanisms for inactivating this gene in bladder cancer appear to be uncommon. 相似文献
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Fifty-eight new anonymous simple sequence repeats (SSR) were generated and mapped to various rat chromosomes. Among them two genes (rat homologs for human cadherin-14 and mouse fibroblast growth factor-related protein) were mapped on Chromosomes (Chrs) 2 and 11 respectively. The majority of markers were generated from a small insert genomic library specific to Chr 11, 13, 14, and 15. Twenty new markers were mapped to Chr 13, which is known to contain a blood pressure quantitative trait locus (QTL). Several approaches to obtain microsatellite markers are described. The protocols and newly generated markers should be useful for ongoing rat genome project. 相似文献
6.
VA Poberskaia LV Kozhelupenko EA Kradinova OI Dement''eva 《Canadian Metallurgical Quarterly》1995,75(4):10-13
A favourable effect of sanatorium treatment on the key body functions was found in children with thyroid hyperplasia consequent to environmental pollution due to Chernobyl accident. It is emphasized that balneofactors in the above children should be used in sparing regimens. 相似文献
7.
Some mechanical and electrical properties of the BPDA/ODA/PDA polyimide film prepared on mylar followed by various cure schedules have been studied. It has been found by FTIR that the imidization reaches its maximum after a 200°C cure schedule for this polyimide. However, the optimum condition of curing is a 350°C cure schedule. Following this cure schedule, one can obtained a polymide film with good mechanical and electrical properties. © 1993 John Wiley & Sons, Inc. 相似文献
8.
本文通过介绍数字信号处理器(DSP)的特点和应用,指出了在高等院校学生实验中引入数字信号处理器的必要性,并且给出了基于数字信号处理器的实验系统构建。 相似文献
9.
Tao Liu Aina He Fengyu Kong Anding Wang Yaqiang Dong Hua Zhang Xinmin Wang Hongwei Ni Yong Yang 《材料科学技术学报》2021,68(9):53-60
The harsh melt-spinning and annealing processes of high saturation magnetization nanocrystalline softmagnetic alloys are the biggest obstacles for their industrialization. Here, we proposed a novel strategy to enlarge the processing window by annealing the partially crystallized precursor ribbons via a heterostructured crystallization process. The heterostructured evolution of Fe84.75Si2B9P3C0.5Cu0.75(at.%)alloy ribbons with different spinning rate were studied in detail, to demonstrate the gradient nucleation and grain refinement mechanisms. The nanocrystalline alloys made with industrially acceptable spinning rate of 25-30 m/s and normal annealing process exhibit excellent magnetic properties and fine nanostructure. The small quenched-in crystals/clusters in the free surface of the low spinning rate ribbons will not grow to coarse grains, because of the competitive grain growth and shielding effect of metalloid elements rich interlayer with a high stability. Avoiding the precipitation of quenched-in coarse grains in precursor ribbons is thus a new criterion for the composition and process design, which is more convenient than the former one with respect to the homogenous crystallization mechanism, and enable us to produce high performance nanocrystalline soft-magnetic alloys. This strategy is also suitable for improving the compositional adjustability, impurity tolerance, and enlarging the window of melt temperature,which is an important reference for the future development of composition and process. 相似文献
10.
Aina Martín-Medina Noemi Cern-Pisa Esther Martinez-Font Hanaa Shafiek Antnia Obrador-Hevia Jaume Sauleda Amanda Iglesias 《International journal of molecular sciences》2022,23(12)
The most frequent cause of death by cancer worldwide is lung cancer, and the 5-year survival rate is still very poor for patients with advanced stage. Understanding the crosstalk between the signaling pathways that are involved in disease, especially in metastasis, is crucial to developing new targeted therapies. Toll-like receptors (TLRs) are master regulators of the immune responses, and their dysregulation in lung cancer is linked to immune escape and promotes tumor malignancy by facilitating angiogenesis and proliferation. On the other hand, over-activation of the WNT signaling pathway has been reported in lung cancer and is also associated with tumor metastasis via induction of Epithelial-to-mesenchymal-transition (EMT)-like processes. An interaction between both TLRs and the WNT pathway was discovered recently as it was found that the TLR pathway can be activated by WNT ligands in the tumor microenvironment; however, the implications of such interactions in the context of lung cancer have not been discussed yet. Here, we offer an overview of the interaction of TLR-WNT in the lung and its potential implications and role in the oncogenic process. 相似文献