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1.
Juniperus communis has been used e.g. as poles (posts), haysticks and wall-coating. In some districts it has even been an important export article. The fields of columnar juniper are the result of a long history of cultivation and grazing. In this article the main types of juniper fields in Sogn, Western Norway are presented, and their relationships to soil conditions and traditional use are discussed. According to structure, utilization and development four main types of juniper fields are recognized: I. Traditional juniper fields, II. Semi-cultural juniper fields, III. Secondary juniper fields and IV. Semi-natural juniper fields. Due to changes in agricultural methods, juniper fields are becoming rare.  相似文献   
2.
Dinucleotide repeat polymorphism at the D11S528 locus   总被引:3,自引:1,他引:2       下载免费PDF全文
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4.
Stabursvik (1959) described the saponin fraction of Narthecium ossifragum as a sarsasapogenin glycoside with the structure arabinosegalactose-xylose-glucose-sarsasapogenin. In a renewed study of the phototoxic lamb disease alveld, in which this saponin has been implicated (Ender 1955), we have looked more closely at the saponin fraction. We find that there are two saponins, one major and one minor. Both have a branched trisaccharide on C-3 of the sapogenin. Galactose is directly attached to C-3 in both saponins. The major saponin has glucose and arabinose attached to galactose, the minor saponin has glucose and xylose. We suggest the names narthecin and xylosin for the spirostanol form of these two saponins. In fresh juice from leaves we find little narthecin, however. Most of the saponin is present in the furostanol form, with glucose on C-26. Enzymatic hydrolysis showed this glucose to be bound as a β-glucoside. From specific rotations in partial hydrolysates we conclude that the saccharide on C-3 is a β-D-glucoside, α-L-araboside, β-D-galactoside.  相似文献   
5.
Isolation of the Arabidopsis ABI3 gene by positional cloning.   总被引:43,自引:11,他引:32       下载免费PDF全文
Arabidopsis abi3 mutants are altered in various aspects of seed development and germination that reflect a decreased responsiveness to the hormone abscisic acid. The ABI3 gene has been isolated by positional cloning. A detailed restriction fragment length polymorphism (RFLP) map of the abi3 region was constructed. An RFLP marker closely linked to the abi3 locus was identified, and by analyzing an overlapping set of cosmid clones containing this marker, the abi3 locus was localized within a 35-kb region. An 11-kb subfragment was then shown to complement the mutant phenotype in transgenic plants, thereby further delimiting the position of the locus. A candidate ABI3 gene was identified within this fragment as being expressed in developing fruits. The primary structure of the encoded protein was deduced from sequence analysis of a corresponding cDNA clone. In the most severe abi3-4 allele, the size of this predicted protein was reduced by 40% due to the presence of a point mutation that introduced a premature stop codon. The predicted ABI3 protein displays discrete regions of high similarity to the maize viviparous-1 protein.  相似文献   
6.
YAC clones corresponding to 125 Arabidopsis thaliana RFLP markers have been identified. At least one YAC clone has been isolated for each of the RFLP markers tested. Based on CHEF gel analysis of 196 clones, the mean insert size of the available Arabidopsis YAC libraries is approximately 160 kb. The YACs of known genetic map location encompass about 30% of the Arabidopsis genome. The results presented here represent a first step towards assembly of an overlapping YAC library of the A. thaliana genome.  相似文献   
7.
The gene encoding the dopamine D2 receptor (DRD2) has been suggested as a candidate gene for several mental disorders. We previously described the cloning and chromosomal mapping (to 11q22-q23) of a human DRD2 gene as well as its use for the detection of a two-allele TaqI RFLP with a minor allele frequency of 0.24, corresponding to a PIC of 0.30. Family linkage utilizing DRD2 would be facilitated if the PIC of the DRD2 locus were increased. To this end, we have used additional phage and cosmid clones in the vicinity of DRD2 to identify a new two-allele TaqI RFLP as well as a TG microsatellite polymorphism with a PIC of 0.62. We report localizations of the three polymorphisms on the restriction map of the DRD2 locus. The TaqI RFLPs are in apparent linkage equilibrium with the microsatellite, yielding a highly informative compound marker locus with a PIC of 0.76.  相似文献   
8.
This study aimed to examine whether lung tissue extracellular matrix (ECM) hydrogels have protective effects on radiation-induced lung injury (RILI). The cytocompatibility and histocompatibility were tested for the obtained ECM-derived hydrogel. Sprague–Dawley rats were randomly divided into three groups (n = 18): control group (control); rats receiving irradiation and intratracheal injection of normal saline (IR + NS); and rats receiving irradiation and intratracheal injection of lung ECM-derived hydrogel (IR + ECM). The wet/dry weight ratio was used to evaluate the congestion and edema of the lungs. Histopathological analysis of lung tissues was performed using hemotoxylin and eosin staining and Masson's trichrome staining. Immunohistochemical staining and western blot analyses were carried out to determine the expression of epithelial–mesenchymal transition (EMT)-related proteins in lung tissues (E-cadherin, α-smooth muscle actin [α-SMA], and vimentin). In addition, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6), hydroxyproline, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were also evaluated. The ECM-derived hydrogels had good cytocompatibility and histocompatibility. ECM-derived hydrogel treatment improved lung histopathology injury and pulmonary edema. Higher expression of E-cadherin and lower expression of vimentin and α-SMA were found in the IR + ECM group compared with those in the IR + NS group. Hydroxyproline levels were reduced by ECM-derived hydrogel treatment compared with those in the IR + NS group. Obvious increases of TNF-α, IL-6, and TGF-β1 were identified following irradiation. Marked reductions in MDA content and increases in SOD were induced by ECM-derived hydrogel treatment in rats after radiation. ECM-derived hydrogels were shown to protect against RILI, potentially by reducing EMT, inflammation, and oxidative damage.  相似文献   
9.
An anthocyanin, 1, with the novel 4-substituted aglycone, 5-carboxypyranopelargonidin, was isolated in small amounts from the acidified, methanolic extract of strawberries, Fragaria ananassa Duch., by preparative HPLC after purification by partition against ethyl acetate, Amberlite XAD-7 and Sephadex LH-20 column chromatography. It was identified mainly by 2D NMR spectroscopy and electrospray LC-MS as the 3-O-beta-glucopyranoside of 5-carboxy-2-(4-hydroxyphenyl)-3,8-dihydroxy-pyrano[4,3,2-de]-1-benzopyrylium, an anthocyanidin which is homologous to 5-carboxypyranomalvidin (vitisidin A) reported in red wines and 5-carboxypyranocyanidin recently isolated from red onions. By comparison of UV-Vis absorption spectra, 1 showed in contrast to 2, pelargonidin 3-O-beta-glucopyranoside, a local absorption peak around 360 nm, a hypsochromic shift (8 nm) of the visible absorption maximum, and lack of a distinct UV absorption peak around 280 nm. The similarities between the absorption spectra of 1 in various acidic and neutral buffer solutions implied restricted formation of the instable colourless equilibrium forms, which are typical for most anthocyanins in weakly acidic solutions. The molar absorptivity (epsilon) of 1 varied little with pH contrary to similar values of for instance the major anthocyanin in strawberry, 2. However, 2 revealed higher epsilon-values than 1 at all pH values except 5.1. At pH 5.1, the epsilon-value of 1 (6250) was nearly four times the corresponding value of 2 (1720), which showed the potential of 5-carboxypyranopelargonidin derivatives as colorants in solutions with pH around 5. The colours of 1 and 2 in buffered solutions with pH 1.1 and pH 6.9 have been described by the CIELAB coordinates h(ab) (hue angle), C* (chroma), and L* (lightness).  相似文献   
10.

Introduction  

Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology.  相似文献   
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