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996.
E M Chernovskaia 《Eksperimental?nai?a onkologii?a》1987,9(4):18-21, 78
The data of literature about the structure of cytoskeleton proteins in the normal and malignant cells are analyzed. The possibilities of using a specific polyclonal serum and a monoclonal antibody for a more precise ascertainment of the origin and diagnostic of tumours are discussed. The intermediate and active filaments may be used as a new class of histochemical markers. Laminin, the protein of basement membranes, probably, plays an important role in metastatic spreading. 相似文献
997.
J. M. Corbett 《Behaviour & Information Technology》1987,6(4):441-453
The role played by technology as a discrete independent variable in shaping the design of work is explored. The concept of coupling is developed and an empirical study of work with advanced manufacturing technology (AMT), using measurement scales derived from this concept, is outlined. Results indicate that operators of tightly coupled AMT perceive stronger supervisory influence on their working methods and show signs of lower intrinsic job satisfaction and poorer mental health than operators of more loosely coupled AMT. Implications for job redesign are discussed. 相似文献
998.
M. A. Koenders 《Acta Mechanica》1987,70(1-4):31-49
Summary The problem of fairly densily packed particles with rate independent though otherwise arbitrary interaction is investigated in two dimensions. It is shown that slow changes in a statistically uniform medium in the pre-failure deformation state can be described by a stiffness tensor. An approximate expression for this tensor is obtained from first principles. The connection with the perfectly random heterogeneous medium is established. A simple example for round rough particles in an isotropic packing of four contacts is given.With 8 Figure 相似文献
999.
First lactation records of 9941 Alpine, 2383 LaMancha, 11,203 Nubian, 3714 Saanen, and 4649 Toggenburg dairy goat does were obtained from the USDA to evaluate relation of registration (purebred, American, or grade) with lactation yield traits (mature equivalent milk and fat yields) and with reason for termination of lactation (normal, sold for dairy, or culled). Does were grouped by age at first kidding (11 through 16 mo or 21 through 26 mo) and by calendar year (1976 through 1978, 1979 through 1981, or 1982 through 1984). Data were analyzed within breed and year group for yield traits and within breed for reason of termination. Registration and age at first kidding accounted for little variation in mature equivalent milk and fat yields or in reason for termination. 相似文献
1000.
M. Yu. Brazhnikov A. A. Levchenko L. P. Mezhov-Deglin 《Instruments and Experimental Techniques》2002,45(6):758-763
A new technique for exciting nonlinear waves on a charged surface of liquid hydrogen is described. Methods of optical detection of surface oscillations in experiments on capillary turbulence at frequencies of up to 10 kHz are discussed. The results of a study of capillary waves on the surface of liquid hydrogen are presented. 相似文献