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1.
On the measurement of growth with applications to the modelling and analysis of plant growth 总被引:3,自引:0,他引:3
M. L. Roderick 《Functional ecology》2000,14(2):244-251
2.
Summary Different staining procedures, various digestion methods and autoradiographic techniques were employed to study the structure and composition of the nucleolus and of the nucleolonema, after unmasking the latter by adenosine treatment. The presence of DNA, RNA, protein and lipid in these structures has been shown. It has been demonstrated that the filamentous structure within the nucleolus — the nucleolonema— has a core of DNA, around which RNA and protein have accumulated. The structure of the nucleolonema suggests that it is in a highly active state, in synthesizing ribosomal RNA and protein.We take the opportunity to express our gratefulness to the Director, Prof. Dr. Hans Lettré, for providing facilities to work in this Institute. We like to thank our other colleagues, particularly Dr. N. Paweletz, for their valuable help during the course of the investigations. 相似文献
3.
Davila Anne-Marie Marchal Rémy Vandecasteele Jean-Paul 《Journal of industrial microbiology & biotechnology》1994,13(4):249-257
Summary Sophorose lipids stand out as biosurfactants with a wide potential for industrial application and which can be produced in good yield from glucose and a lipidic cosubstrate.Candida bombicola CBS 6009 (ATCC 22214) was used in the present study. The influence of the lipidic cosubstrate on various aspects of production performance of these glycolipids (final concentration, yield) and on product composition (in particular, the structure of the hydroxy fatty acid vegetable and animal oils, markedly influenced product composition. In terms of production performance, the best substrates were oils or esters rich in C18:0 and C18:1 fatty acids. Optimal overall performance was obtained with esters (340 g L–1 sophorose lipids with rapeseed esters). Conclusions drawn from the results allow predictive evaluation of lipidic industrial substrates. 相似文献
4.
LDL的氧化修饰和氧化修饰LDL的组成和结构变化 总被引:8,自引:1,他引:7
与低密度脂蛋白(LDL)相比,氧化修饰LDL(O-LDL)的组成、结构和生物学特性发生了深刻的变化,而组成和结构的改变是生物学特性改变的基础.本文根据最近文献资料.结合我们实验室的工作.对LDL的氧化修饰、O-LDL的组成、结构改变,以及它们的机理作一简要综述. 相似文献
5.
6.
S V Rana S Mehta J S Chopra C K Nain U K Dhand J Mehta 《Journal of medical primatology》1984,13(4):205-217
An experimental model of protein calorie malnutrition (PCM) was created in young rhesus monkeys. Ulnar and tibial nerves from six monkeys with PCM, six rehabilitated and 12 control monkeys were studied for lipid composition and activity of myelin marker enzyme. Total lipids, myelin marker lipids and activity of myelin marker enzyme, 2', 3'-cyclic nucleotide 3' - phosphohydrolase were decreased, while esterified cholesterol and free fatty acids were increased in PCM as compared to controls. There was partial recovery in myelin marker lipids and complete restoration of other lipids on nutritional rehabilitation. 相似文献
7.
Michel Becker 《Plant Ecology》1980,40(3):155-161
Summary In a previous study, 772 floristics relevés, made in a large forest on calcareous soils (north-east France), had been treated by factorial analysis of correspondences in order to establish a site typology. The third axis separated chiefly Fagus and Quercus, which are very common in the forest, and various other ligneous or herbaceous species (see fig. 1). Two groups of relevés, homogeneous as for edaphic conditions, were choosen, having a significant position on this axis (with either positive or negative values). From this, floristic tables have been elaborated; they show clearly the influence of silvi culture (here high forest or coppice-with-standards) on part of both ligneous and herbaceous flora. Considering plant sociology, it appears that treating a stand as a coppice-with-standards can convert a Melico-Fagetum typicum (Eu-Fagion) into a Querceto Carpinetum typicum (Fraxino-Carpinion), and a Carici-Fagetum (Cephalanthero-Fagion) into a Querceto-Carpinetum primuletosum (Fraxino-Carpinion). Fortunately a large number of species are not influenced by the silviculture; this allows the identification of isopotential sites. Possible ecological causes are briefly discussed.
Nomenclature suivant: P. Fournier, 1961. Les quatre flores de France. Edition P. Le Chevalier, Paris. 1154 p. 相似文献
8.
The lamellar membrane stacks of Ectothiorhodospira mobilis were isolated and purified by a combination of lysozyme and osmotic shock treatment, followed by differential and density gradient centrifugation. Preparations of lamellar membranes were enriched at least 2.4-fold in the ratio of bacteriochlorophyll a to protein.Thin-sectioning, negative staining, platinumcarbon shadowing and freeze-etching were used to study the architecture of the membrane units. Both platinum-carbon shadowing and freeze-etching showed the outer surfaces of the isolated lamellar membrane stacks to be relatively smooth. Particles averaging 7 nm in diameter were seen on several faces following freeze-ctching.Non-polar amino acids amounted to 60% of the total amino acid composition. Lipids constituted 32% of the membrane dry weight. Phosphatidyl ethanolamine and diphosphatidyl glycerol were the major phospholipids. Fatty acids of 10–15 carbons represented a small fraction of both membrane and whole cell fatty acids. Monoenes constituted 36% of the total membrane fatty acids and 38.4% of the total whole cell fatty acids. The major fatty acids of both whole cells and purified membranes were C16:0, C18:1 and cyclopropane C19:0. 相似文献
9.
《Journal of Asia》2020,23(2):430-438
The bacterial community living in the insect gut may play an important role in nutrition, immunity and protection, detoxification of toxins, and inter- and intra-specific communication. Rice leaffolder Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Crambidae) is a notorious pest in rice, and the diversity of the gut bacteria of C. medinalis across life stages are not well understood. Here, the diversity and abundance of the gut bacterial community in C. medinalis through life stages were investigated using Illumina Miseq technology. A total of 22 bacterial phyla, 42 classes, 100 orders, 179 families, 350 genera and 395 species were identified across the different life stages of C. medinalis. Proteobacteria and Firmicutes phyla were the dominant bacterial taxa. Members of the genera Enterococcus, unclassified Enterobacteriaceae, Wolbachia, Acinetobacter, Stenotrophomonas, Microbacterium, Bacillus, Corynebacterium, Lampropedia, and Sphingobacterium were found at all life stages. Enterococcus and unclassified Enterobacteriaceae occupied higher relative abundance among bacteria community in the 2nd to 5th instar larvae, pupae and adults. The structure of bacterial community differed across the life stages of C. medinalis. Our findings will enrich the understanding of gut bacteria in C. medinalis, and will provide foundation and assistance for the development of novel pest management strategies through utilization of microbiota. 相似文献
10.
Marie-Annette Carbonneau Emeline Cartron Claude-Louis Leger Christiane Senglat Bernard Descomps 《Free radical research》2013,47(2):127-142
Oxidized low density lipoprotein (LDL) plays an important role in atherogenesis. It is generally thought that LDL is mainly oxidized in the intima of vessel walls, surrounded by hydrophilic antioxidants and proteins such as albumin. The aim of this study was to investigate the possible interrelationships between oxidation resistance of LDL and its protein and lipid moieties. Proteins and to a lesser extent lipids, appeared to be the major determinants in the LDL Cu 2+ -oxidation resistance, which in turn depend on the ultracentrifugation (UC) procedure used. Comparing high speed/short time (HS/ST, 4 u h), high speed/long time (HS/LT, 6-16 u h) and low speed/long time (LS/LT, 24 u h) conditions of UC, HS with the shortest time (4 u h) led to prepare LDL (named LDL·HS-4 u h) with higher total protein and triglyceride contents, unchanged total cholesterol, phospholipids and Vitamin E, and higher Cu 2+ -oxidation resistance. Among proteins, only albumin allows to explain changes. PAF acetyl hydrolase appeared to be unaffected, whereas its pro-oxidant role was established and found only in the absence of albumin. In contrast the pro-oxidant role of caeruloplasmin took place regardless of the albumin content of LDL. The antioxidant effect of albumin (the oxidation lag time was doubled for 20 u mol/mol albumin per LDL) is assumed to be due to its capacity at decreasing LDL affinity for Cu 2+ . Interestingly, the LDL·HS-4 u h albumin content mirrored the intrinsic characteristics of LDL in the plasma and was not affected by added free albumin. Moreover, it has been verified that in 121 healthy subjects albumin was the best resistance predictor of the Cu 2+ -oxidation of LDL·HS-4 u h, with a multiple regression equation: lag time (min)=62.1+0.67(HSA/apoB)+0.02 (TG/apoB) m 0.01(TC/apoB); r =0.54, P <0.0001. Accounted for by lag time, the oxidation resistance did not correlate with f -tocopherol and ubiquinol contents of LDL. The mean albumin content was about 10 u mol/mol, and highly variable (0-58 u mol/mol) with subjects. The LDL·HS-4 u h may account for the status of LDL in its natural environment more adequately than LDL resulting from other conditions of UC. 相似文献