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101.
Rudolph J O'Callaghan DJ Osterrieder N 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(1):31-36
The genome of equine herpesvirus type 1 (EHV-1) strain RacL11, a highly virulent isolate obtained from an aborted foal, and that of the modified live vaccine strain KyA, were cloned as bacterial artificial chromosomes (BAC) in Eseherichia coli. Mini F plasmid sequences were inserted into the viral genomes by homologous recombination instead of the gene 71 (EUS4) open reading frame after co-transfection of viral DNA and recombinant plasmid pdelta71-pHA2 into RK13 cells. After isolation of recombinant viruses by three rounds of plaque purification, viral DNA was isolated from RK13 cells infected with RacL11 or KyA virus mutants expressing the green fluorescent protein (GFP), and electroporated into Escherichia coli DH10B cells. Several bacterial colonies were shown to contain high-molecular weight BAC DNA with a restriction enzyme fragment pattern indicative of the presence of full-length RacL11 or KyA genomes. Two selected BAC clones were analysed by restriction enzyme analysis and Southern blotting, and were eventually termed pRacLI I and pKyA. respectively. Upon transfection of pRacL11 or pKyA DNA into RK13 cells, GFP-expressing fluorescing virus plaques could be identified from day 1 after transfection. Infectivity after transfection of pRacL11 or pKyA could be readily propagated on RK13 or equine cells, indicating that infectious full-length DNA clones of strains RacL11 and KyA were successfully cloned in Escherichia coli as BACs. The glycoprotein 2-negative progeny reconstituted from pRacL11 and pKyA (L11deltagp2 and KyAdeltagp2) exhibited different growth properties. Whereas both L11deltagp2 and KyAdeltagp2 extracellular titres were reduced by 15- to 32-fold, plaque diameters were only markedly (50%) reduced in the case of KyAdeltagp2. 相似文献
102.
Anna Carbone Barbara Parrino Paola Barraja Virginia Spanò Girolamo Cirrincione Patrizia Diana Armin Maier Gerhard Kelter Heinz-Herbert Fiebig 《Marine drugs》2013,11(3):643-654
2,5-bis(3′-Indolyl)pyrroles, analogues of the marine alkaloid nortopsentin, were conveniently prepared through a three step procedure in good overall yields. Derivatives 1a and 1b exhibited concentration-dependent antitumor activity towards a panel of 42 human tumor cell lines with mean IC50 values of 1.54 μM and 0.67 μM, respectively. Investigating human tumor xenografts in an ex-vivo clonogenic assay revealed selective antitumor activity, whereas sensitive tumor models were scattered among various tumor histotypes. 相似文献
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106.
Determining some parameters of capillary moisture transport in porous building materials. Part 3: Tests on mortars and sands Because a mortar component ultimately belongs to brickwork, the contribution of sand, which serves as an aggregate, to capillary liquid rise was investigated. Since up to now this kind of transport can only be observed with difficulty, as also confirmed by experiment, due to complex interaction of the individual characteristic values, an attempt was made to also enhance present experience on other material than brick. 相似文献
107.
A 6-year trial was laid out with varied PK fertilization on fen soil and analysed for the capability of undersown clover species to fix atmospheric nitrogen. No mineral nitrogen was applied. On an average of the six test years, the share of white clover in the total crop yield of the sward was 17% after sowing once and that of red clover or Swedish clover was 19% after sowing twice. The annual mean shares of these two clover variants in the total yield varied only slightly over the test period. White clover showed typical seasonal dynamics in the test years, with yield portions increasing from spring to late summer. Undersown red and Swedish clovers reached the highest yield percentages in their 2nd and 3rd growths. The variants grown without PK fertilizer and clover yielded 45 dt DM ha???1. With PK fertilizer dry matter yields increased to 57 and 68 dt ha???1, respectively. With supplemental white clover or red/Swedish clover sown into the sward, substantial amounts of symbiotic nitrogen were accumulated in the harvestable plant matter, giving a total dry matter yield of 76 dt ha???1. Clover yield shares up to 30% resulted in increasing DM yields which, however, declined again with even larger shares of clover. As to the ingredients of grasses, herbs and clover, the differences were mostly significant. On an average of the six test years, nitrogen fixation was 58.4?kg ha???1 for white clover and 46.6?kg ha???1 for red/Swedish clover. 相似文献
108.
The present study on the sediment production in natural forests was carried out on an 13,284 ha area,ocated in Guilan Province, in the north of Iran. This area is under intensive management. We first analyzed the physi- sal factors of the area. Then, the amount of road construction, afforestation and harvested wood volume, as well as the harvesting method in the region were determined for the years between 1993 and 2010. The results show that the aver- age annual amount of sediment production in the entire region, over this 18-year period, has increased annually at a rate of 3.54 t.km-2 (R2 = 0.56) at a confidence level of 95%. Operations management and management methods used in :his forest area has affected the amount of sediment production. Clear cutting and extensive harvesting methods in the region caused an increase in the amount of sediment production, as indicated by a coefficient of determination of 0.71, mplying that forest management may be considered effective and in harmony with the environment. 相似文献
109.
Irene Flickinger Barbara C Rütgen Wilhelm Gerner Ivana Calice Alexander Tichy Armin Saalmüller Miriam Kleiter 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(2):207-214
To evaluate radiosensitivity and the effects of radiation on the expression of vascular endothelial growth factor (VEGF) and VEGF receptors in the canine oral melanoma cell line, TLM 1, cells were irradiated with doses of 0, 2, 4, 6, 8 and 10 Gray (Gy). Survival rates were then determined by a MTT assay, while vascular endothelial growth factor receptor (VEGFR)-1 and -2 expression was measured by flow cytometry and apoptotic cell death rates were investigated using an Annexin assay. Additionally, a commercially available canine VEGF ELISA kit was used to measure VEGF. Radiosensitivity was detected in TLM 1 cells, and mitotic and apoptotic cell death was found to occur in a radiation dose dependent manner. VEGF was secreted constitutively and significant up-regulation was observed in the 8 and 10 Gy irradiated cells. In addition, a minor portion of TLM 1 cells expressed vascular endothelial growth factor receptor (VEGFR)-1 intracellularly. VEGFR-2 was detected in the cytoplasm and was down-regulated following radiation with increasing dosages. In TLM 1 cells, apoptosis plays an important role in radiation induced cell death. It has also been suggested that the significantly higher VEGF production in the 8 and 10 Gy group could lead to tumour resistance. 相似文献
110.
To better promote forest resource management and strengthen the development of forest carbon sink marketization, this paper studied the accounting of forest carbon sinks from 2003 to 2008 based on a system of national accounts(SNA) and data from the latest forest resources inventory in China. The study calculated the value of forest carbon stocks at a total of RMB817.13 × 10~9 yuan in 2003 and RMB 839.93× 109 yuan in 2008, with an average annual increase of 0.55 % from an increase in physical carbon sinks. The total value of forest carbon sinks in 2003 and 2008 was RMB 26.73 × 10~9 yuan and RMB 29.77 × 10~9 yuan, respectively, with an average annual growth of 2.18 %. From 2003 to 2008, both stock and flow value of forest carbon sinks increased, but the total net flow value of carbon sinks decreased. The growth rate for the environmentally adjusted Gross Domestic Product(ea GDP) for China's forest carbon sinks was 17.23 %, outstripping the average growth rate of 9.5 % for the GDP during the same period. The study also indicates that China's forest carbon sinks affects the GDP in the range of 0.25–0.26 %, and its economic potential is not relatively huge. 相似文献