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131.
132.
Abnormal dark-adapted ERG in cats heterozygous for a recessively inherited rod-cone degeneration 总被引:1,自引:0,他引:1
Purpose To study retinal function in cats homozygous and heterozygous for a recessively inherited rod‐cone degeneration. Methods Dark‐adapted electroretinograms (ERGs) were performed on early affected, heterozygous (ophthalmoscopically normal), and clinically normal, nonrelated cats. Responses to blue stimuli over a 3.9‐log unit range were recorded. Results Lower b‐wave amplitudes than normal were observed in heterozygotes and early affected cats. The amplitudes of the heterozygotes took an intermediate position between normal and early affected cats. Normalized amplitude/intensity data suggest a normal dynamic range in carriers. B‐wave implicit times in carriers were comparable to those of normal cats. Conclusions These results show that heterozygotes have an altered retinal function, although they are ophthalmoscopically normal. It is difficult to electrophysiologically differentiate heterozygotes from affected cats with the very early stage of retinal degeneration. 相似文献
133.
Genetic diversity in 79 European accessions of the Barley Core Collections was surveyed using isozyme electrophoresis. A total of 26 alleles were observed at the ten isozyme loci. All loci were polymorphic except Pgd-1 which was monomorphic. The comparison of the results with those of previous studies indicates that most of the alleles occurring in the European Barley are also observed in this set of the European Barley Core Collections. Only five alleles (Est-1 Al; Est-5 Ag, Te; Pgi-1 C and Ndh-2 B) were absent. Nine of 26 alleles were rare alleles, which were detected only in one or two accessions. Moreover, most of rare alleles were detected in 6-rowed winter barley. It is very important to include rare alleles for maximising the genetic variations in core collections. In the set of European Barley Core Collection, 6-rowed barley contained larger diversity than 2-rowed barley; winter type contained larger diversity than spring type. The cluster analysis separated 79 accessions into three major groups. Group I is more complex and comprised 2-rowed spring, 2-rowed winter and 6-rowed winter barley. In this group, 18 accessions in the cluster A and 14 accessions in the cluster B possessed identical genotypes as judged from the ten isozyme data. Principal coordinate analysis could not clearly separate the spring cultivars from the winter barley lines, as well as not separate 2-rowed from 6-rowed barley. 相似文献
134.
135.
Bjærke O, Østbye K, Lampe HM, Vøllestad LA. Covariation in shape and foraging behaviour in lateral plate morphs in the three‐spined stickleback. Ecology of Freshwater Fish 2010: 19: 249–256. © 2010 John Wiley & Sons A/S Abstract – In three‐spined stickleback (Gasterosteus aculeatus) colonisation of freshwater has led to rapid evolution in various morphological and behavioural traits. Examples are reduction in lateral plate number and increased benthic foraging. These changes are believed to result from natural selection, but the evolutionary mechanisms driving behavioural changes and how such changes are associated with phenotypes, are poorly understood. Here, we study three different lateral plate morphs from a brackish water lake and one morph from a river upstream. We investigate if the lateral plate morphs differ in overall body shape and then experimentally test how foraging behaviour differ among morphs and with body shape. Foraging behaviour is measured as the consumption efficiency of benthic and pelagic prey types. The results show that lateral plate morphs differ in overall body shape and that body shape significantly co‐varies with foraging behaviour. 相似文献
136.
F H Gage A Bj?rklund U Stenevi S B Dunnett P A Kelly 《Science (New York, N.Y.)》1984,225(4661):533-536
Grafts of fetal septal tissue rich in cholinergic neurons were implanted as a dissociated cell suspension into the depth of the hippocampal formation in aged rats with severe impairments in spatial learning abilities. After 2 1/2 to 3 months, the rats with grafts, but not the controls, had improved their performance in a spatial learning test. Their improvement was due, at least in part, to an increased ability to use spatial cues in the task. In all animals the grafts had produced an extensive acetylcholinesterase-positive terminal network in the surrounding host hippocampal formation. Thus, the action of cholinergic neurons in the graft onto elements in the host hippocampal circuitry may be a necessary, but perhaps not sufficient, prerequisite for the observed functional recovery. 相似文献
137.
Human monoclonal antibodies to Pf 155, a major antigen of malaria parasite Plasmodium falciparum 总被引:16,自引:0,他引:16
R Udomsangpetch K Lundgren K Berzins B W?hlin H Perlmann M Troye-Blomberg J Carlsson M Wahlgren P Perlmann A Bj?rkman 《Science (New York, N.Y.)》1986,231(4733):57-59
Pf 155, a protein of the human malaria parasite Plasmodium falciparum, is strongly immunogenic in humans and is believed to be a prime candidate for the preparation of a vaccine. Human monoclonal antibodies to Pf 155 were obtained by cloning B cells that had been prepared from an immune donor and transformed with Epstein-Barr virus. When examined by indirect immunofluorescence, these antibodies stained the surface of infected erythrocytes, free merozoites, segmented schizonts, and gametocytes. They bound to a major polypeptide with a relative molecular weight of 155K and to two minor ones (135K and 120K), all having high affinity for human glycophorin. The antibodies strongly inhibited merozoite reinvasion in vitro, suggesting that they might be appropriate reagents for therapeutic administration in vivo. 相似文献
138.
Curtis MA Kam M Nannmark U Anderson MF Axell MZ Wikkelso C Holtås S van Roon-Mom WM Björk-Eriksson T Nordborg C Frisén J Dragunow M Faull RL Eriksson PS 《Science (New York, N.Y.)》2007,315(5816):1243-1249
The rostral migratory stream (RMS) is the main pathway by which newly born subventricular zone cells reach the olfactory bulb (OB) in rodents. However, the RMS in the adult human brain has been elusive. We demonstrate the presence of a human RMS, which is unexpectedly organized around a lateral ventricular extension reaching the OB, and illustrate the neuroblasts in it. The RMS ensheathing the lateral olfactory ventricular extension, as seen by magnetic resonance imaging, cell-specific markers, and electron microscopy, contains progenitor cells with migratory characteristics and cells that incorporate 5-bromo-2'-deoxyuridine and become mature neurons in the OB. 相似文献
139.
Since 1983, the Norwegian environmental authorities have given financial support to operational liming and research following recommendation given by the Norwegian Liming Project (1979–1984). Liming all acid waters in Norway would require an annual expenditure exceeding NOK (Norwegian Kroner) 300 × 106. The funding level for 1988 is NOK 14 × 106 and will probably increase to NOK 30 mill. by 1990, including NOK 1 to 3 mill. for research and development. Priority is given to lakes and rivers whose fishing is open to the public, and to save or restore valuable fish populations. Local support in the form of voluntary labor is a condition for financial aid. Two salmon rivers are currently included in the program. T h e Norwegian Institute for Water Research (NIVA) plays an important role in liming research and development in Norway. The aims of this research are twofold: to document the chemical and biological response to neutralization and liming, and to improve liming strategy to obtain cost efficient liming activities. 相似文献
140.
Lauer B Ottleben I Jacobsen HJ Reinard T 《Journal of agricultural and food chemistry》2005,53(4):899-904
The selection of synthetic antibody fragments from large phage libraries has become a common method for the generation of specific antibodies. The technique is particularly valuable when antibodies against small, non-immunogenic molecules (haptens) or highly toxic substances have to be produced. In addition, haptens are usually coupled to protein carriers, bearing the risk that the free hapten is not detectable. Here, a single variable chain antibody (scFv) against the highly toxic mycotoxin fumonisin B1 has been produced. The hapten was coupled via a linker to biotin. Using this conjugate and a naive scFv library, it was possible to circumvent both the necessity of immunization and the risk of a disguised hapten. The scFv obtained after three panning rounds was found to bind specifically to both free fumonisin B1 and fumonisin-biotin conjugate. Also fumonisin B2 was bound by the scFv. Modeling of both scFv and fumonisin B1 molecule revealed a good fitting of structures. The antibody obtained can potentially be used for developing a rapid and affordable immunoassay for detection of food contamination and can be applied in immunoaffinity chromatography, usually carried out prior to HPLC analysis of mycotoxin-contaminated food and feed. 相似文献