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31.
Melanotic neuroectodermal tumor of infancy (MNTI) is a rare but well-documented lesion of neuroectodermal derivation. Maturation of the neural elements has been reported only occasionally. We report a case of MNTI of the maxilla showing maturation of neural elements to ganglionic cells. 相似文献
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A systematic study of microbend effects in singlemode optical fibers is presented. An algorithm is developed to characterize optical attenuation as a function of the spatial period of the microbend deformation. Optical attenuation peaks are described in terms of central wavelength, amplitude, and spectral width. An excellent correlation is shown between the experimental results and the theoretical predictions, with nominal errors of less than 2.5% 相似文献
34.
The addition of malonaldehyde (MA) results in significant changes in the visco-elastic behaviour of wheat flour dough. Incorporation of MA in wheat flour also enhances its rate of maturation during subsequent storage. After storage, MA treated wheat flour had lesser extensibility and higher resistance, dough development time and stability than the untreated sample. Altered visco-elastic behaviour of wheat flour has been explained by the reaction of MA with sulphohydryl and amino groups. 相似文献
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Methallibure administration caused reduction of gonadal weights in female rats and mice indicative of suppression of pituitary gonadotrophins. In the ovaries of the methallibure treated females, there was a great atresia of the follicles and of the corpora lutea. Methalbure caused atrophic changes in the endometrial lining of the vagina. Uterine horns became thin after methallibure treatment. A significant decrease in protein, RNA and sialic acid concentration in uterus and vagina was observed following methallibure treatment. Uterus of treated animals showed decreased glycogen contents. Histological and biochemical changes in the female genital tract of rats and mice suggested that the drug caused antifertility effect due to its possible antiestrogenic action. 相似文献
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Paul P. Lynn Santosh K. Arya 《International journal for numerical methods in engineering》1973,6(1):75-88
This paper presents a new method of formulating the finite element relationships based on the least squares criterion. To overcome the high degree of inter-element continuity, a method of reducing the original governing differential equation to a set of equivalent system of first-order differential equations is proposed. The validity of the method is demonstrated by means of several numerical examples. In particular, application of the method to problems with unknown variational functionals is considered. 相似文献
40.
A. Bouazzi J.J. Loferski M. Kwietniak R.R. Arya M. Sosnowski 《Journal of power sources》1984,12(2):167-172
Minority carrier diffusion lengths in thin film p-CuInSe2 and n-CdS were determined from the decay of the short-circuit current generated by the electron beam of a scanning electron microscope (SEM) for different accelerating voltages. The bulk diffusion lengths were determined taking into account the surface recombination velocity at the scanned surface: they were 0.6 μm in CuInSe2 and 1.17 μm in CdS. 相似文献