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Agnieszka M. Wusatowska-Sarnek Martin J. Blackburn Mark Aindow 《Materials Science and Engineering: A》2003,360(1-2):390-395
Methods are described for sample preparation of polycrystalline Ni-based superalloys in order to perform a detailed microstructural characterization. Specific techniques for the precise definition of the various phases present are outlined and these are shown to be useful for the measurement of size, volume fractions and distribution. A number of optical, scanning and transmission microscopy techniques are used to provide the necessary information. 相似文献
35.
Analysis of non-stationary electrochemical oscillations emerges utilization of the techniques allowing an observation of time evolution of their parameters such as instantaneous frequency, amplitude or frequency band. An algorithm of extraction of these parameters can be based on one of linear or quadratic time-frequency representations of oscillations record. In this paper, the authors present representatives of such transformations (Choi-Williams and Cone-shaped) originating from one of the most popular joint time-frequency energy distribution—Wigner-Ville distribution. Short introduction to the mathematics of the topic discussed is provided, then the authors present an example of application in the analysis of current oscillations of copper dissolution process. 相似文献
36.
The expression of cytokeratins (CK), involucrin, vimentin, CD34, and alpha-smooth-muscle actin was studied in fetal and adult hair follicles. The first stage of the developing hair follicle is characterized by palisaded, elongated epithelial cells budding from the epidermal basal layer. These cells express CK5/6, CK14, CK17, CK19, and vimentin. During the following weeks of gestation, different structures in the developing hair follicle can be identified and characterized. The matrical cells display only CK19. The keratinocytes of the outer root sheath express CK5/6, CK14, CK17, CK19, and involucrin; those of the inner root sheath, CK4, CK18, and involucrin; those of the isthmus, the same profile as the ORS. In the infundibulum, the basal-layer keratinocytes express CK5/6, CK14, CK17, and CK19, whereas in the suprabasal layers CK1, CK4, CK10, CK14, and CK17 are seen. The adult hair follicle in anagen fails to express CK19 in the matrical cells and isthmus and both CK17 and CK19 in the infundibulum. These profiles of intermediate filaments and other markers appear to be potentially useful in categorizing neoplasms with apparent follicular differentiation. 相似文献
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Phospholamban (PLN) was expressed in Escherichia coli as a protein fusion with glutathione S-transferase (GST). GST-PLN was mostly present in the insoluble protein fraction and accounted for approximately 50% of total insoluble protein. Attempts to suppress inclusion body formation or to use GST as an affinity-purification tag failed. A successful purification method is based on preparative SDS/PAGE and electrodialysis. From 1 g cells we typically purified 13.5 mg fusion protein with a PLN content of 2.8 mg. We genetically inserted an enterokinase (EK) protease site just in front of the PLN sequence and demonstrated the proteolytical liberation of PLN from the carrier protein. The approach described represents a substantial advancement in PLN expression and purification. 相似文献
39.
We report a 20 month old female patient with diploid-triploid mixoploidy (46,XX/69,XXX) syndrome with hypothyroidism and precocious puberty. The triploid cell line was only expressed in the fibroblast culture and comprised the majority (95%) of the cells. Chromosome analysis of the fetal blood sample and peripheral blood sample were normal. The patient shows typical features of full triploidy (growth and severe mental retardation, cranial and facial dysmorphism, complete syndactyly of fingers 3/4, partial syndactyly of toes 2/3) and facial but no body asymmetry. At the age of 5 months central hypothyroidism and precocious puberty were diagnosed. Thin pigmented streaks were visible on the wrists and legs of the patient at the age of 16 months. This is the first patient reported so far with 46,XX/69,XXX mixoploidy suffering from hypothyroidism and precocious puberty. 相似文献
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M Souquet T Restle R Krebs SF Le Grice RS Goody BM W?hrl 《Canadian Metallurgical Quarterly》1998,37(35):12144-12152