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951.
Comparison of the three basic scattering functions of myoglobin in solution with those from the known structure in crystalline state 总被引:2,自引:0,他引:2
H B Stuhrmann 《Journal of molecular biology》1973,77(3):363-369
X-ray small-angle scattering of myoglobin in aqueous solutions enhances the probability that the structure of myoglobin is conserved on passing to the dissolved state. The agreement of measured and calculated results could be extended up to which roughly corresponds to 5 Å resolution. 相似文献
952.
The lipid composition of swimming spores, cysts and five hour germlings was established. Spores utilized triglycerides first, then phospholipids. Upon encystment all glycolipid components decreased, while in germlings the phospholipids, monoglycerides and sterol esters exhibited a marked increase. 相似文献
953.
R B Reisberg 《Life sciences》1974,14(10):1965-1973
Choline acetyltransferase activity in homogenates, or in partially purified extracts of rat brain cerebra, was increased by 11–37% in the presence of ethanol when incubated at 38°C with [14C] acetyl-CoA, choline chloride and alcohol concentrations of 0.17M to 1.02M. In preincubation experiments with enzyme preparations and ethanol, inactivation of the enzyme by the alcohol, which occurs at incubation times longer than 20 minutes, could be at least partially prevented by the addition of certain components of the incubation mixture to the preincubation mixture. 相似文献
954.
955.
Michael S. Lipkowitz Edgar Leal-Pinto B. Eleazar Cohen Ruth G. Abramson 《Glycoconjugate journal》2002,19(7-9):491-498
UAT, also designated galectin 9, is a multifunctional protein that can function as a urate channel/transporter, a regulator of thymocyte-epithelial cell interactions, a tumor antigen, an eosinophil chemotactic factor, and a mediator of apoptosis. We review the evidence that UAT is a transmembrane protein that transports urate, describe our molecular model for this protein, and discuss the evidence from epitope tag and lipid bilayer studies that support this model of the transporter. The properties of recombinant UAT are compared with those of urate transport into membrane vesicles derived from proximal tubule cells in rat kidney cortex. In addition, we review channel functions predicted by our molecular model that resulted in the novel finding that the urate channel activity is regulated by sugars and adenosine. Finally, the presence and possible functions of at least 4 isoforms of UAT and a closely related gene hUAT2 are discussed. Published in 2004. 相似文献
956.
957.
B?rbel Maus Camille Jung Jestinah M. Mahachie John Jean-Pierre Hugot Emmanuelle Génin Kristel Van Steen 《PloS one》2013,8(10)
Complex human diseases commonly differ in their phenotypic characteristics, e.g., Crohn’s disease (CD) patients are heterogeneous with regard to disease location and disease extent. The genetic susceptibility to Crohn’s disease is widely acknowledged and has been demonstrated by identification of over 100 CD associated genetic loci. However, relating CD subphenotypes to disease susceptible loci has proven to be a difficult task. In this paper we discuss the use of cluster analysis on genetic markers to identify genetic-based subgroups while taking into account possible confounding by population stratification. We show that it is highly relevant to consider the confounding nature of population stratification in order to avoid that detected clusters are strongly related to population groups instead of disease-specific groups. Therefore, we explain the use of principal components to correct for population stratification while clustering affected individuals into genetic-based subgroups. The principal components are obtained using 30 ancestry informative markers (AIM), and the first two PCs are determined to discriminate between continental origins of the affected individuals. Genotypes on 51 CD associated single nucleotide polymorphisms (SNPs) are used to perform latent class analysis, hierarchical and Partitioning Around Medoids (PAM) cluster analysis within a sample of affected individuals with and without the use of principal components to adjust for population stratification. It is seen that without correction for population stratification clusters seem to be influenced by population stratification while with correction clusters are unrelated to continental origin of individuals. 相似文献
958.
B.A. Whitton 《欧洲藻类学杂志》2013,48(1):121-123
The conventions at present used in the classification of blue-green algae frequently prove unsatisfactory. A solution is suggested which requires the simultaneous use of two different approaches. When a binomial is essential the flora of Geitler (1932) should be adequate for most purposes, but any long term attempt to sort out the present chaos will require the use of numerical taxonomy. This dual approach will necessitate various practical changes in current methods of naming and reporting on blue-green algae. 相似文献
959.
I. Denholm 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1998,353(1376):1757-1767
For many key agricultural pests, successful management of insecticide resistance depends not only on modifying the way that insecticides are deployed, but also on reducing the total number of treatments applied. Both approaches benefit from a knowledge of the biological characteristics of pests that promote or may retard the development of resistance. For the whitefly Bemisia tabaci (Gennadius), these factors include a haplodiploid breeding system that encourages the rapid selection and fixation of resistance genes, its breeding cycle on a succession of treated or untreated hosts, and its occurrence on and dispersal from high-value crops in greenhouses and glasshouses. These factors, in conjunction with often intensive insecticide use, have led to severe and widespread resistance that now affects several novel as well as conventional control agents. Resistance-management strategies implemented on cotton in Israel, and subsequently in south-western USA, have nonetheless so far succeeded in arresting the resistance treadmill in B. tabaci through a combination of increased chemical diversity, voluntary or mandatory restrictions on the use of key insecticides, and careful integration of chemical control with other pest-management options. In both countries, the most significant achievement has been a dramatic reduction in the number of insecticide treatments applied against whiteflies on cotton, increasing the prospect of sustained use of existing and future insecticides. 相似文献
960.
Structure and Functions of Channel-Forming Peptides: Magainins,Cecropins, Melittin and Alamethicin 总被引:26,自引:0,他引:26
B. Bechinger 《The Journal of membrane biology》1997,156(3):197-211