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991.
Iveta Yotova Quanah J. Hudson Florian M. Pauler Katharina Proestling Isabella Haslinger Lorenz Kuessel Alexandra Perricos Heinrich Husslein Ren Wenzl 《International journal of molecular sciences》2021,22(16)
Endometriosis is a common gynecological disorder characterized by ectopic growth of endometrium outside the uterus and is associated with chronic pain and infertility. We investigated the role of the long intergenic noncoding RNA 01133 (LINC01133) in endometriosis, an lncRNA that has been implicated in several types of cancer. We found that LINC01133 is upregulated in ectopic endometriotic lesions. As expression appeared higher in the epithelial endometrial layer, we performed a siRNA knockdown of LINC01133 in an endometriosis epithelial cell line. Phenotypic assays indicated that LINC01133 may promote proliferation and suppress cellular migration, and affect the cytoskeleton and morphology of the cells. Gene ontology analysis of differentially expressed genes indicated that cell proliferation and migration pathways were affected in line with the observed phenotype. We validated upregulation of p21 and downregulation of Cyclin A at the protein level, which together with the quantification of the DNA content using fluorescence-activated cell sorting (FACS) analysis indicated that the observed effects on cellular proliferation may be due to changes in cell cycle. Further, we found testis-specific protein kinase 1 (TESK1) kinase upregulation corresponding with phosphorylation and inactivation of actin severing protein Cofilin, which could explain changes in the cytoskeleton and cellular migration. These results indicate that endometriosis is associated with LINC01133 upregulation, which may affect pathogenesis via the cellular proliferation and migration pathways. 相似文献
992.
For the modeling of the mechanical behavior of a two phase alloy with the rule of mixture (RM), the flow stress of both phases is needed. In order to obtain these information for the α′‐martensite in high alloyed TRIP‐steels, compression tests at cryogenic temperatures were performed to create a fully deformation‐induced martensitic microstructure. This martensitic material condition was subsequently tested under compressive loading at ?60, 20, and 100°C and at strain rates of 10?3, 100, and 103 s?1 to determine the mechanical properties. The α′‐martensite possesses high strength and surprisingly good ductility up to 60% of compressive strain. Using the flow stress behavior of the α′‐martensite and that of the stable austenitic steel AISI 316L, the flow stress behavior of the high alloyed CrMnNi TRIP‐steel is modeled successfully using a special RM proposed by Narutani et al. 相似文献
993.
粉末冶金齿轮由于材料中残留有孔隙,和用切削加工铸锻材料制造的零件相比,强度与耐磨性较差,不适用于重负载应用.通过横向辗压,利用选择性表面致密化,可显著改进粉末冶金齿轮的强度与耐磨性.这篇论文阐述了用压制、烧结、选择性表面致密化、表面硬化及根据要求的品质水平可能还有最后珩磨,制造轿车变速器的粉末冶金螺旋齿轮.研究了各种参数,诸如材料组成、横向辗压与热处理的工艺参数对致密化与硬度深度、孔隙形态、显微组织、齿轮齿廓、DIN品质以及表面粗糙度的影响.初步研究是在3轴的总成成对试验台架上进行的,其表明粉末冶金齿轮具有高负载承载能力. 相似文献
994.
A. Lorenz J. Ott M. Harrer E.A. Preissner A.H. Whitehead M. Schreiber 《Journal of Electroceramics》2001,6(1):43-54
Two novel chemical processing routes were developed for the production of ZnO-based varistor powders and compared with the conventional mixed-oxide route. The central idea behind the new techniques was to separate the minority components in relation to their function and incorporate them into the varistor powders accordingly. The densification of green bodies prepared by the chemical routes proceeded in one or two stages (at 770 °C and 910 °C) compared to many stages for the conventional route. The sintered pellets thus produced from the chemical routes showed smaller grain sizes, higher densities and more evenly distributed intergranular phases than those from the conventional mixed-oxide route. 相似文献
995.
Aylward LL Charnley G Goodman J Rhomberg L 《Environmental science & technology》2008,42(6):2201; author reply 2202-2201; author reply 2203
996.
Henzler S. Koeppe S. Lorenz D. Kamp W. Kuenemund R. Schmitt-Landsiedel D. 《Solid-State Circuits, IEEE Journal of》2008,43(7):1666-1676
Time-to-digital converters (TDCs) are promising building blocks for the digitalization of mixed-signal functionality in ultra-deep-submicron CMOS technologies. A short survey on state-of-the-art TDCs is given. A high-resolution TDC with low latency and low dead-time is proposed, where a coarse time quantization derived from a differential inverter delay-line is locally interpolated with passive voltage dividers. This high-resolution TDC is monotonic by construction which makes the concept very robust against process variations. The feasibility is demonstrated by a 90 nm demonstrator which uses a 4x interpolation and provides a time domain resolution of 4.7 ps. An integral nonlinearity of 1.2 LSB and a differential nonlinearity of 0.6 LSB are achieved. The resolution restrictions imposed by an uncertainty of the stop signal and local variations are derived theoretically. 相似文献
997.
Lorenz Ratke Prof. Dr.-Ing. 《Beton- und Stahlbetonbau》2008,103(4):236-243
Fabrication and Properties of a New Light Weight Concrete: Aerogel Concrete The distribution of super hydrophobic aerogel in particulate form into conventional cement or concrete mixtures produces a light weight concrete with extraordinary properties: good heat and sound insulation, fire protection of the class F120 and better, armorable und easy workable. The paper describes the fabrication and some properties of this new construction material. 相似文献
998.
999.
DJ Garry GA Ordway JN Lorenz NB Radford ER Chin RW Grange R Bassel-Duby RS Williams 《Canadian Metallurgical Quarterly》1998,395(6705):905-908
Myoglobin, an intracellular haemoprotein expressed in the heart and oxidative skeletal myofibres of vertebrates, binds molecular oxygen and may facilitate oxygen transport from erythrocytes to mitochondria, thereby maintaining cellular respiration during periods of high physiological demand. Here we show, however, that mice without myoglobin, generated by gene-knockout technology, are fertile and exhibit normal exercise capacity and a normal ventilatory response to low oxygen levels (hypoxia). Heart and soleus muscles from these animals are depigmented, but function normally in standard assays of muscle performance in vitro across a range of work conditions and oxygen availability. These data show that myoglobin is not required to meet the metabolic requirements of pregnancy or exercise in a terrestrial mammal, and raise new questions about oxygen transport and metabolic regulation in working muscles. 相似文献
1000.
Nagib Chamon Lorenz Dobereiner 《Bulletin of Engineering Geology and the Environment》1988,38(1):37-43
The presence of caverns in sandstones on the border of the Amazon sedimentary basin, which could cause problems to the watertightness of artificial reservoirs in this area, has justified a study of the different geophysical methods which could be used to detect such features from the surface. One particular area, with the presence of a cavern of approximatively 300 m in lengh was chosen, for this study. The methods tested were the electroresistivity, magnetometry, gravimetry and VLF-EM. The gravimetric survey was the most successful for the direct detection of the cavern, but the other methods could be useful in detecting geological features which could be associated with the presence of these features. 相似文献