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21.
We report a case of implantation of a new design of stent which allows creation of a double-hemispheric lumen for the treatment of a bifurcational stenosis. The unfavourable outcome following the implantation of this stent is described.  相似文献   
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Genes controlling proliferation and differentiation of astrocytes are likely to play an important role in the pathogenesis of astrocytic gliomas and could serve as therapeutic targets. mRNA differential display analysis identified two genes, viz. BAALC and RAMP3, whose expression is altered in primary astrocytes treated with differentiation inducers. BAALC, which has been reported to be expressed in neural progenitor cells, was found to be up regulated in both normal and malignant astrocytes on inhibition of proliferation. RAMP3 functions as a modulator of the receptor for adrenomedullin (AM). AM has been suggested to act as autocrine/paracrine growth factor for gliomas. Our studies show RAMP3 down regulation on staurosporine treatment of astrocytes, suggesting protein kinase C inhibition as a possible strategy for inhibiting AM activity and thereby growth of glioma cells.  相似文献   
23.
Irradiation induced synthesis of asparagine synthetase was localized in the nucleus of the potato buds. Isolated nuclei were capable of incorporating amino acids into asparagine synthetase protein and the process was inhibited by cycloheximide (100%), puromycin (73%) and by feed back inhibitor β-aspartyl hydroxamate (100%). Preincubation of the bud tissue with actinomycin D was necessary to express its inhibitory effect.  相似文献   
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Cyclooxygenases (COXs) catalyze the rate-limiting step in the production of prostaglandins, bioactive compounds involved in processes such as fever and sensitivity to pain, and are the target of aspirin-like drugs. COX genes have been cloned from coral, tunicates and vertebrates, and in all the phyla where they are found, there are two genes encoding two COX isoenzymes; it is unclear whether these genes arose from an early single duplication event or from multiple independent duplications in evolution. The intron-exon arrangement of COX genes is completely conserved in vertebrates and mostly conserved in all species. Exon boundaries largely define the four functional domains of the encoded protein: the amino-terminal hydrophobic signal peptide, the dimerization domain, the membrane-binding domain, and the catalytic domain. The catalytic domain of each enzyme contains distinct peroxidase and cyclooxygenase active sites; COXs are classified as members of the myeloperoxidase family. All COXs are homodimers and monotopic membrane proteins (inserted into only one leaflet of the membrane), and they appear to be targeted to the lumenal membrane of the endoplasmic reticulum, where they are N-glycosylated. In mammals, the two COX genes encode a constitutive isoenzyme (COX-1) and an inducible isoenzyme (COX-2); both are of significant pharmacological importance.  相似文献   
26.
Merkouropoulos G  Shirsat AH 《Planta》2003,217(3):356-366
We detail the expression of the Arabidopsis thaliana (L.) Heynh. atExt1 extensin gene. atExt1 is normally expressed in roots and inflorescences, and is induced by wounding, exogenously supplied salicylic acid, methyl jasmonate, auxins and brassinosteroids. Northern assays and histochemical analysis of transgenics expressing an atExt1:: gus fusion show that this gene is also induced by the brassica pathogen Xanthomonas campestris pv. campestris and that this induction is restricted to tissues close to the site of infection. Expression at regions of abscission and senescence also implicates atExt1 in these important developmental processes.  相似文献   
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In etiolated pea and maize leaves illuminated after incubation at 38 degreesC, a new dark reaction was shown manifested in the bathochromic shift of spectral bands and accompanied by esterification of the product of protochlorophyllide photochemical reduction--Chld 684/676: Chld 684/676 --> Chl 688/680. After completion of the reaction a rapid (20-30 sec) quenching of the fluorescence of the reaction product (Chl 688/680) was observed. The reaction Chld 684/676 --> Chl 688/680 is inhibited under anaerobic conditions and in the presence of cyanide; the reaction accompanied by Chl 688/680 fluorescence quenching is not observed in pea mutants with impaired function of photosystem II reaction centers. The spectral properties of the formed Chl form with the absorption maximum at 680 nm, fluorescence quenching, and simultaneous synthesis of pheophytin suggest that the reaction is connected with the chlorophyll of photosystem II reaction center--P-680.  相似文献   
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We report a patient who received a stent following intracoronary 3-irradiation. Despite a good initial angiographic result, the stent appeared to be not fully expanded on intravascular ultrasound imaging at 6-month follow-up. Four months later, sudden thrombotic occlusion occurred shortly after aspirin cessation.  相似文献   
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The expression of extA, an extensin gene from Brassica napus L. (oilseed rape) was examined in transgenic Nicotiana tabacum L. (tobacco) and untransformed Brassica juncea L. and B. napus tissues. Northern analysis showed that this gene maintained its normal pattern of expression when transferred to tobacco. In transgenic tobacco plants containing an extA promoter/-glucuronidase coding sequence fusion, expression of extA was detected in the external and internal phloem of the main stem. High expression levels were seen in cortical parenchyma cells at the point where the axillary flowering branch joined the main stem. Expression was greatest in regions where the maximum tensile stress would seem to be exerted on the main stem by the weight of the axillary branch. It was confirmed that this expression pattern was due to tensile stress by using weights to induce expression of the fusion gene in axillary flowering stalks. In B. juncea pods, in-situ hybridisation studies showed that the extensin gene was strongly expressed in cells of the carpel walls within which considerable tensile stresses develop.Abbreviations GUS -glucuronidase - X-GLUC 5-bromo-4-chloro-3-indolyl glucuronide - SSC saline sodium citrate We thank the Biotechnology and Biological Sciences Research Council for funding this research, and Mrs. W. Grail for her expertise in histochemical technique. Ms. J. Spence is the recipient of a Biotechnology and Biological Sciences Research Council post-graduate studentship award.  相似文献   
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