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I V Lur'e  E B Presman 《Genetika》1979,15(5):912-916
Isolated cyclopia is one of the members of the prosencephalic teratologic series. In some families with cyclopian monster other types of prosencephalic malformations are found in sibs or more distant relatives. All these malformations occur more frequently in females. Different forms of prosencephalies are observed in the same type of chromosome disbalance. These data suggest that morphogenesis and etiology of the prosencephalic malformations are common. Therefore a whole teratologic series but not a single member-malformation must be an object of genetic analysis. The same data are found for another teratologic series: bilateral renal agenesis--unilateral one--aplastic variant of the cystic dysplasia of kidneys. Polygenic inheritance with the threshold phenomenon is the most probable type of genetic determination of such malformations. The more frequent occurrence of polygenic malformations in families with the studied malformation whose inheritance is not yet established may be an indirect indication for the polygenic determination of the latter.  相似文献   

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Animal and human blood serum contains great amount of blocked (or "silent") immunoglobulins which, being activated by heating to 60 degrees C, pH decrease to 2.0-2.5 or treatment with 5M KSCN acquire a capacity to interact with different antigens. This interaction may be equally prevented or weakened by both identical and serologically non-related antigen, i.e. activated immunoglobulins are polyspecific. Polyspecific immunoglobulins show less affinity in comparison with monospecific antibodies, their interaction with antigens depends considerably on temperature.  相似文献   

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Evidence for the presence of the metal-binding protein metallothionein, MT, in higher plants is equivocal. Although a number of MT-like metal complexes have been isolated from plants, the chemical structures of most of these compounds have not been fully elucidated. Recently a novel class of plant peptides, poly (γ-glutamylcysteinyl) glycines, (γEC)nG, have been discovered. These peptides bind metal ions, and in the presence of such ions the amount of (γEC), G in plant cells increases. The presence of peptide bonds through the γ-carboxyl group of glutamate, rather than the α-carboxyl group, suggests that these peptides are not encoded by structural genes but are the products of biosynthetic pathways. Cells which are resistant to supra-optimal concentrations of certain metal ions over-produce (γEC)n G. (γEC)n G. may be functional analogues of MT. Whether or not some plants also produce MT is an important question which remains to be answered.  相似文献   

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Fifty hearts of corpses of humans of different age groups were studied by means of macro-microscopical anatomical dissection of muscle fibres and cardiac blood vessels. The muscle bridges were found over the coronary arteries in all preparations of the heart. They were most frequently met on the anterior interventricular branch of the left coronary artery. The topography of muscle bridges is described and the miocardium muscle bundles participating in their formation are revealed. The character of the course of fibres in the muscle bridge is related to the course of the fibres of the muscle bundle forming it.  相似文献   

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The repeatability coefficient of sire evaluation by daughters performance in different lactations was 0.38-0.70, that suggests the necessity to specify annually the previous sire evaluation on receiving new daughters performance data. When using the "daughters-mothers" method the repeatability coefficients of sire evaluation by dairy indexes, milk fat content and total milk fat production (0.41, 0.52 and 0.45 respectively) were significantly higher than those obtained by the "daughters-herdmates" method (0.25, 0.30 and 0.28 respectively). Thus, sire progeny testing evaluation should be carried out simultaneously by both methods. Nevertheless, the "daughters-mothers" method is preferable.  相似文献   

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The light and electron-microscopy original data and other morphological and physiological findings reveal that a population of cortical neurones is gathered in compact cell clusters (blocks, ensembles, modules) and most of neurones participate in maintaining such modules by their axonal ramifications. Some elements of cell clusters may be joined by associative, callosal and projectional thalamic afferents. Authors' new findings are discussed in relation with corresponding literature data. The main attention is given to the self-organization of cortical modules.  相似文献   

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When protanopes or deuteranopes arrange the Farnsworth Dichotomous Test colors in order of similarity, they reveal their lack of red/green hue discriminations by alternating chips that the normal trichromat sees as reddish and greenish test colors. The dichromatic orderings follow a systematic variation in saturation of blue hues through neutral and into yellow hues as described by theory for each of the two types. Some dichromats who show the typical test behavior nevertheless use reddish and greenish hue terms appropriately when instructed to name the same test colors. Lightness cues are probably used by these dichromats in the naming task but ignored in the perceptual similarity task. Thus, unlike normal trichromats, who use similar names for perceptually similar colors, dichromats may use dissimilar names for perceptually similar colors. In this way they can achieve concordance with the normative language system despite its discordance with their impoverished color perceptions.  相似文献   

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Nixon AE  Firestine SM 《IUBMB life》2000,49(3):181-187
A familiar refrain within industrial circles is better, faster, and cheaper. Efforts to place this mantra into practice within the biotechnology industry has brought a focus on protein engineering as one method to create new products quickly and inexpensively. Typically, protein engineering has utilized either rational design or combinatorial methods, both of which have been explored and improved in recent years. Continued advancement in these two areas and their application to an increasing list of industrially and medically important processes mean that the number of "synthetic" proteins displacing old technologies is likely to grow at an amazing rate over the next few years. We discuss some of the technologies available for protein redesign and illustrate these with examples from the biocatalysis, biosensor, and therapeutic fields.  相似文献   

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以斑叶红雀珊瑚叶片为外植体,在愈伤组织诱导培养基上 20d 后产生浅黄绿色愈伤组织;转入幼芽分化培养基中 20~25d 后逐渐产生幼芽;外植体直接接入幼芽分化培养基培养 30d 后,可从外植体表面产生绿色幼芽。所产生的幼芽转至生根培养基上可长根,并发育成完整再生植株。  相似文献   

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Ribosomal gene sequences were obtained from bryozoans in the genus Bugula and their bacterial symbionts; analyses of host and symbiont phylogenetic trees did not support a history of strict cospeciation. Symbiont-derived compounds known to defend host larvae from predation were only detected in two out of four symbiotic Bugula species.  相似文献   

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The relationship between the angiosperm families Apiaceae and Araliaceae (order Apiales) has been difficult to resolve, due in large part to problems associated with taxa characterized by a mixture of features typical of both families. Among such confounding groups are the araliads Delarbrea, Pseudosciadium, Myodocarpus, Mackinlaya, and Apiopetalum and many members of Apiaceae subfamily Hydrocotyloideae. Traditional systems have often envisioned these taxa as phyletic intermediates or bridges between the two families. To reevaluate the phylogenetic position of the "intermediate" araliad genera, molecular data were collected from nuclear (rDNA ITS) and plastid (matK) sequences from a complete or near-complete sampling of species in each genus. When analyzed with samples representing the other major clades now recognized within Apiales, results confirm and expand the findings of previously published studies. The five araliad "intermediates" are placed within two well-supported clades clearly segregated from the "core" groups of both Apiaceae and Araliaceae. These segregate clades closely parallel traditional definitions of the araliad tribes Myodocarpeae (Delarbrea, Pseudosciadium, and Myodocarpus) and Mackinlayeae (Mackinlaya and Apiopetalum), and relationships among the species within these clades are largely supported by morphological and anatomical data. Based on these results, Myodocarpeae and Mackinlayeae may best be treated as distinct families. This approach would render four monophyletic groups within Apiales, to which a fifth, Pittosporaceae, cannot at present be excluded. Sampling of taxa from Hydrocotyloideae remains preliminary, but results confirm previous studies indicating the polyphyly of this subfamily: hydrocotyloid taxa may be found in no fewer than three major clades in Apiales.  相似文献   

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