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21.
Simone Ottonello Giovanni Maraini Mario Mammi Hugo L. Monaco Paola Spadon Giuseppe Zanotti 《Journal of molecular biology》1983,163(4):679-681
Crystals of human plasma retinol-binding protein have been obtained from 4.5 m-NaCl buffered at pH 6.8 with 20 mm-cacodylate. The crystals are trigonal with space group R3 and unit cell dimensions, referred to the hexagonal system. . The crystals diffract to a resolution of 2.0 Å. 相似文献
22.
In various applications one faces the problem of estimating a signal from discontinuous observations. For example, in biomedical applications the signal may be the ‘state’ of a given organ and one observes through an external counter the amount of radioactivity sequestered by the organ after injection of a radioactive tracer. Here the problem is studied in the context of nonlinear filtering when the signal can be modelled as either a random variable or a diffusion process, and the observations have a continuous and a purely discontinuous component; both components may be affected by the signal. When the signal is a random variable an explicitly computable solution is obtained; for the diffusion case the solution is given as a sequence of approximating filters that can be computed recursively. 相似文献
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Dr. Gastone Giovanni Nussdorfer 《Cell and tissue research》1970,103(3):398-409
Summary The structural changes of the zona juxtamedullaris of the rat adrenal cortex at birth, have been examined by the light and the electron microscope. In this zone clusters of medullary cells lying among the strands of cortical tissue were observed. In the inner portion of the zona juxtamedullaris two types of adrenocortical cells were found: light and very-dark cells. The latter are smaller than the light cells and are always in close connection with the medullary tissue. The ultrastructural features of the very-dark cells suggest that these elements are in degeneration. This finding supports the hypothesis that at birth there is a partial degeneration of the rat zona juxtamedullaris, i.e. the zone corresponding to the fetal zone of some mammalian species.It is proposed that in all mammalian species at birth there is a partial regression of the zona juxtamedullaris and that the regression of the fetal zone is only the quantitative increase of this phenomenon. This hypothesis is discussed in relation to numerous data demonstrating that there are enzymatic conditions in the rat during fetal life, which permit a discrete hypertrophy of the adrenal cortex.The author wishes to express his appreciation to Dr. A. Gambino and to Mr. G. Gottardo for technical assistance. 相似文献
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Facchiano Angelo; Facchiano Antonio; Facchiano Francesco; Ragone Raffaele; Colonna Giovanni 《Bioinformatics (Oxford, England)》1989,5(4):299-303
A flexible package designed to study protein structure is described.The package is devoted to the analysis of protein sequencesby drawing structural profiles of specific structure-relatedamino acid parameters. An Aminoacidic Parameters Data Bank (CHAMP)containing 32 different series of physico-chemical parametersof amino acids is available. Sequences can be loaded from anyASCII format data bank or from keyboard. The program possessesa routine which enables easy updating of the protein data bankand CHAMP Data Bank. FAST reads statistical correlations betweentwo plots in order to identify structural similarities. Plotscan be printed, saved or used for correlation, comparison orgraph overlap by using common spreadsheets (e.g. Lotus 123).Plots can be smoothed by a running mean or a running median.The program also has a special featurea global flexibilityanalysis of proteins. The package runs on IBM or compatiblesand requires DOS 3.0 or later.
Received on June 20, 1989; accepted on August 2, 1989 相似文献
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B Bottazzi N Nobili A Mantovani 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(12):4878-4882
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Antonella Di Biase Serafina Salvati Giovanni Serlupi Crescenzi 《Neurochemical research》1989,14(2):153-156
We have developed a simple method involving high-performance thin layer chromatographic separation of total brain and myelin lipids. Only two solvent systems consisting of chloroform: methanol: acetic acid and water at different concentrations were needed. The plate was then stained with three sequential procedures to visualize phospholipids, cholesterol and galactolipids. Densitometric procedure at each step of staining was utilized to obtain quantitative analysis of brain and myelin samples. 相似文献
30.
J M Wang Z G Chen G J Cianciolo R Snyderman F Breviario E Dejana A Mantovani 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(6):2012-2017
The effects of IL-1 on vascular endothelium result in a complex set of alterations which are potentially disruptive of vessel wall and underlying tissue integrity. The present study was aimed at investigating possible regulation of such potentially destructive responses elicited by IL-1 on endothelial cells. Culture supernatants of IL-1-treated human umbilical vein endothelial cells (HEC) were depleted of retroviral p15E-related Ag with immobilized anti-p15E mAb. The monocyte chemotactic and polarizing activity of supernatants of IL-1-treated HEC (presumably related to colony-stimulating factors being released by HEC) was markedly augmented by absorption on immobilized anti-p15E antibodies. Irrelevant IgG had no effect and anti-p15E antibodies did not affect the chemotactic activity of supernatants from unstimulated HEC. The material eluted from Sepharose-bound anti-p15E antibodies was devoid of chemotactic and polarizing activity and suppressed the polarization and migration of monocytes in response to chemoattractants. The alpha and beta molecular species of IL-1 were equally effective in inducing the production of p15E-related inhibitor. The production of a p15E-related inhibitor of chemotaxis induced by IL-1 in HEC may represent a negative signal in the regulation of the potentially destructive responses to pro-inflammatory cytokines. 相似文献