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1.
1. In rat kidney cortex, outer and inner medulla the development of activities of seven enzymes was investigated during postnatal ontogeny (10, 20, 30, 60 and 90 days of age). The enzymes were selected in such a manner, as to characterize most of the main metabolic pathways of energy supplying metabolism: hexokinase (glucose phosphorylation, HK), glycerol-3-phosphate dehydrogenase (glycerolphosphate metabolism or shunt, GPDH), triose phosphate dehydrogenase (glycolytic carbohydrate breakdown, TPDH), lactate dehydrogenase (lactate metabolism, LDH), citrate synthase (tricarboxylic acid cycle, aerobic metabolism, CS), malate NAD dehydrogenase (tricarboxylic acid cycle, intra-extra mitochondrial hydrogen transport, MDH) and 3-hydroxyacyl-CoA-dehydrogenase (fatty acid catabolism, HOADH). 2. The renal cortex already differs metabolically from the medullar structures on the 10th day of life. It displays a high activity of aerobic breakdown of both fatty acids and carbohydrates. Its metabolic capacity further increases up to the 30th day of life. 3. The outer medullar structure is not grossly different from the inner medulla on the 10th day of life. Further it differentiates into a highly aerobic tissue mainly able to utilize carbohydrates. It can, however, to some extent, also utilize fatty acids aerobically and produce lactate from carbohydrates anaerobically. 4. The inner medullar structure is best equipped to utilize carbohydrates by anaerobic glycolysis, forming lactate. This feature is already pronounced on the 10th day of life, its capacity increases to some extent during postnatal development, being highest between the 10th and the 60th day of life.  相似文献   
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W Nagl  F A Popp 《Cytobios》1983,37(145):45-62
There are a number of biological phenomena and events that cannot yet be adequately described, such as cell growth and differentiation, which may be controlled by physical factors. Fr?hlich (1980) has discussed the principles of dissipative structures as applied to electromagnetic interactions in relation to basic couplings in biological systems. Recently, increasing evidence of photon storage and ultraweak photon emission from living systems, particularly from DNA, has suggested the concept of an electromagnetic model of differentiation, based on the known quantum optical properties of nucleic acids. This model has the advantage over all ideas so far published, that it is (1) simple; (2) universally applicable to events in living matter, because it is consistent with both the quantum mechanical and the thermodynamic properties on the one hand, and the known biological and biochemical data and phenomena at the other hand; (3) it not only describes the phenomena and events in terms of pure mathematical parameters, but it can also explain them; and (4) it escapes the difficulty of finding basic control mechanisms, which themselves do not need a regulator, ad infinitum.  相似文献   
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Normative adontometric data are presented on a sample of 100 adult Cercopithecus aethiops(51 male, 49 female). When correlation effects among the teeth were held constant through multivariate canonical analyses, contributions of individual tooth loci to the male-female distance were found to be similar to those isolated by univariate means. The present study fails to support Garn’s field theory of sex dimorphism. When these patterns of sexual dimorphism were contrasted with those of three other conspecific groups, the anterior teeth were found to show greater intrapopulation variation than the posterior teeth. This, together with the finding that Penrose’s shape distances between the groups were greater for anterior than postcanine teeth, provides evidence in support of Suolé’s hypothesis. The latter suggests, inter alia, that high coefficients of variation indicate a proportionately higher environmental than hereditary contribution to phenotypic variation. Negative correlations between tooth size and coefficients of variation suggest that tooth-size variability is related to size rather than occlusal complexity.  相似文献   
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Normative odontometric data are presented on a sample of 66 adult thick-tailed bushbabies Otolemur crassicaudatus(34 male, 32 female). This species is characterized by low levels of sexual dimorphism, with univariate differences centered on the canines and the maxillary third molar. Multivariate canonical analysis isolates a third discriminator, the maxillary second molar. Stepwise discriminant analyses, performed after jackknifing, indicate high percentages of correct classification (males, 79.8–81.8%;females, 81–85.2%). When variability profiles consisting of arrays of CVs are compared, males and females are found to share similar patterns. Data for maxillary teeth offer support for Gingerich’s occlusal complexity model, while morphogenetic clusterings within regressions of variability on tooth size conform to those previously reported in other species. These relationships are lost in the mandibular dentition, suggesting an independence of upper from lower toothsize determination.  相似文献   
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Cyclic voltammetry data were obtained for delta 1-pyrroline-2-carboxylate, delta 3-thiazoline-4-carboxylate, delta 2-thiazoline-2-carboxylate and their complexes with Cu(II), Fe(III), and Fe(II). The free ligands were reduced at about -0.35 V and were oxidized in the range of 0.42-0.52 V. Complexing the imine carboxylates with metal ions produces reduction and oxidation in the ranges of 0.05-0.37 V and 0.52-0.74 V, respectively. Prior reports show that these ligands take part in various biological functions. We propose that electron transfer may be involved in some aspects of the physiological activity. The captodative effect can be applied.  相似文献   
8.
Photon reemission in the ultraweak intensity range that is observed after irradiation of cell suspensions with light, reveals characteristic differences between normal human amnion cells and transformed Wish cells from the same parental tissue. The reemission kinetics, approximated best by a hyperbolical process, were studied as a function of cell density, showing that: malignant Wish cells have a photon storage capacity that is not improved by increasing the cell density; and that normal amnion cells exhibit a photon storage capacity that strongly increases with increasing cell density. The interpretation of this effect and the nature of the emitter are discussed.  相似文献   
9.
We describe the first protein of mammalian origin that induces the growth and differentiation of resting B lymphocytes. A proline-rich protein has been isolated from sheep colostrum. A purified proline-rich protein preparation (PRPP) induced resting mouse B cells into and supported their progression through the cell cycle at frequencies comparable with those seen for LPS. Differentiation of resting B cells to plaque formation was also supported as efficiently by PRPP as it was by LPS. However, PRPP was distinct from LPS in that it supported the growth and differentiation of resting B cells derived from either C3H/Tif or C3H/HeJ mice. Splenocytes from neonatal mice responded robustly to PRPP with the growth and differentiation of contained B cells to plaque formation. Unlike LPS, PRPP did not induce detectable Ig isotype switching.  相似文献   
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The primary structures of the alpha chains in hemoglobins from three stocks of mice with theHba w2,Hba w3, andHba w4 haplotypes were determined to establish whether the tentative alpha-chain assignments based on the results of isoelectric focusing patterns were correct. TheseHba haplotypes were identified in laboratory descendants of feral mice captured in different parts of the world. Hemoglobin from Centreville, Maryland,Mus musculus domesticus (Hba w2) contains equal amounts of alpha chains 1 and 3. Hemoglobin from CzechMus musculus musculus (Hba w4) contains equal amounts of alpha chains 3 and 4. Amino acid analysis of the alpha-globins of Skive DanishMus musculus musculus (Hba w3) establishes that its hemoglobin is comprised of about one-third alpha chain 2 as expected plus a greater amount of a unique alpha chain that has not been described previously. This unique alpha chain has glycine at position 25, isoleucine at position 62, and serine at position 68; it is called chain 7. It may represent an intermediate in the evolution of genes that code for chain 2 (which has glycine, valine, and serine at positions 25, 62, and 68, respectively) and chain 4 (which has valine, isoleucine, and serine at positions 25, 62, and 62, respectively).This research was sponsored jointly by the National Institutes of Environmental Health Sciences under Contract 1-ES-55078 and by the Office of Health and Environmental Research, U.S. Department of Energy, under Contract DE-AC05-840R21400 with Martin Marietta Energy Systems, Inc.  相似文献   
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