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51.
The combination of cell microenvironment control and real‐time monitoring of cell signaling events can provide key biological information. Through precise multipatterning of gold nanoparticles (GNPs) around cells, sensing and actuating elements can be introduced in the cells' microenviroment, providing a powerful substrate for cell studies. In this work, a combination of techniques are implemented to engineer complex substrates for cell studies. Alternating GNPs and bioactive areas are created with micrometer separation by means of a combination of vacumm soft‐lithography of GNPs and protein microcontract printing. Instead of conventional microfluidics that need syringe pumps to flow liquid in the microchannels, degas driven flow is used to fill dead‐end channels with GNP solutions, rendering the fabrication process straightforward and accessible. This new combined technique is called Printing and Vacuum lithography (PnV lithography). By using different GNPs with various organic coating ligands, different macroscale patterns are obtained, such as wires, supercrystals, and uniformly spread nanoparticle layers that can find different applications depending on the need of the user. The application of the system is tested to pattern a range of mammalian cell lines and obtain readouts on cell viability, cell morphology, and the presence of cell adhesive proteins.  相似文献   
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A new family of extinction-pulses (E-pulses), called subsectional-polynomial E-pulses, is presented. This new type of E-pulse is constructed by choosing polynomials of degree Q as subsectional basis-functions in the E-pulse expansion. The main feature of this family of E-pulses is that the waveforms are continuous and smooth. Several topics concerning the E-pulse technique are investigated, such as: insensitivity to the exact number of natural modes present in the target response; aspect-angle independence; and effects of additive white Gaussian noise. Numerical results, using the response of a thin cylinder and a sphere, show that the subsectional-polynomial E-pulses improve the results obtained using subsectional-rectangular E-pulses  相似文献   
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Tibial torsion?     
A longitudinal study evaluating the degree of rotation of the bimalleolar axis of tibia and fibula at birth, 6 month, 12 months and 24 months revealed a gradual statistically significant external rotation from a mean of 4 degrees at birth to a mean of 11 degrees at 24 months. There was no correlation with the sex or race of the child or with the age at which the child began independent walking. It is concluded that this external rotation is a part of normal growth and development of the infants' lower extremities.  相似文献   
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The uni-arterial vascularisation of the lateral bilary duct makes it impossible to systematise the arteries which supply the common bile duct. Only the cystic artery is seen at coelio-mesenteric catheterization. The techniques essential for visualisation of the cystic artery are discussed, on the basis of one hundred coelio-mesenteric arteriograms: frequency of demonstration, origin, course, termination, calibre and length. The frequent finding of opacification of the wall of the gall bladder under normal conditions is stressed.  相似文献   
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There are two forms of ornithine decarboxylase with respect to pyridoxal 5'-phosphate (pyridoxal-P) affinity in exponentially-growing Swiss 3T3 mouse fibroblasts: form I (Km approximately 10 muM) accounts for 30% of the total activity, and form II (Km approximately 0.4 muM) the remainder. Each form of the enzyme is in rapid equilibrium with ornithine and pyridoxal-P; neither form recognizes the Schiff base between ornithine and pyridoxal-P as a substrate. Total pyridoxal-P concentrations indicate that both forms may normally be at least partially active in vivo. Upon stimulation of 3T3 cells by pituitary growth factors, form I becomes undetectable within 4 h. As total activity increases over 10-fold during this time and continues to increase thereafter, a possible conversion of form I to form II could account for this increase only if the Km change reflects other changes in preexisting enzyme. The rates of cofactor dissociation are apparently the same for each form and neither rate changes with the growth state. Since rapid equilibrium kinetics apply, the forms apparently differ in their rate of cofactor association. The half-lives of the two forms in vivo are the same in unstimulated cells when measured concurrently. Also, the half-life of total activity decreases markedly upon stimulation as form II becomes dominant. These and other observations are not consistent with pyridoxal-P serving a major protective function for the enzyme in vivo.  相似文献   
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Serum complement levels were assayed in 26 patients with disseminated cancer, who received immunotherapy with infusion of C. parvum. Complement activation, indicated by the consumption of C3 or C4 or both, was found in 46% of the patients. Serum samples showed direct correlation between decreased C3 and conversion of C3 proactivator, whereas such conversion did not occur when C4 alone was decreased. It is concluded that the bypass (properdin) pathway was activated in patients in whom C3 consumption was detected, while the classical (C1) pathway was activated in the patients with C4 consumption unaccompanied by C3 decrease. Direct correlation was observed between delayed cutaneous hypersensitivity reactions to recall antigens and the incidence of C. parvum-associated complement activation.  相似文献   
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