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Summary Multiple shoots were induced from cotyledonary nodes of grasspea (Lathyrus sativus L.) derived from 7-d-old in vitro seedlings on Murashige and Skoog (MS) medium containing N6-benzyladenine (BA), kinetin, or thidiazuron, BA being the most effective. Among the five genotypes tested, shoot proliferation frequency was the highest (93.3%) for IC-120487, giving the maximum number of shoots (11.3 shoots per explant) on MS medium augmented with 2.0 mgl−1 (8.87 μM) BA. Shoot cultures were established by repeatedly subculturing the original cotyledonary nodes on fresh medium after each harvest of the newly formed shoots. Thus 30–40 shoots were obtained in 2 mo. from a single cotyledonary node. Up to 81.8% of the shoots developed roots following transfer to half-strength MS medium containing 0.5 mgl−1 (2.85 μM) indole-3-acetic acid. Plantlets were successfully acclimatized and established in soil.  相似文献   
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A Streptomyces strain UK10 was isolated from Ukrainian soil and identified by taxonomical studies as Streptomyces arenae var ukrainiana. HA-2-91 was isolated from the biomass of S. arenae var ukrainiana and is supposedly a polyene macrolide antibiotic belonging to the tetraene group. HA-2-91 showed promising antifungal activity (in vitro) against yeasts and filamentous fungi, including plant pathogens and dermatophytes and was found to be less toxic in mice than nystatin and rimocidin.  相似文献   
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The understanding of erythrocyte deformation under conditions of high shear stress and short exposure time is central to the study of hemorheology and hemolysis within prosthetic blood contacting devices. A combined computational and experimental microscopic study was conducted to investigate the erythrocyte deformation and its relation to transient stress fields. A microfluidic channel system with small channels fabricated using polydimethylsiloxane on the order of 100 mum was designed to generate transient stress fields through which the erythrocytes were forced to flow. The shear stress fields were analyzed by three-dimensional computational fluid dynamics. Microscopic images of deforming erythrocytes were experimentally recorded to obtain the changes in cell morphology over a wide range of fluid dynamic stresses. The erythrocyte elongation index (EI) increased from 0 to 0.54 with increasing shear stress up to 123 Pa. In this shear stress range, erythrocytes behaved like fluid droplets, and deformed and flowed following the surrounding fluid. Cells exposed to shear stress beyond 123 Pa (up to 5170 Pa) did not exhibit additional elongation beyond EI=0.54. Two-stage deformation of erythrocytes in response to shear stress was observed: an initial linear elongation with increasing shear stress and a plateau beyond a critical shear stress.  相似文献   
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Background

Choroidal metastases from gynaecological primary are extremely rare. There is no documented case in the literature of choroid metastasis in a patient with primary peritoneal carcinoma (PPC).

Methods & Results

We describe the first case of a 54-year-old woman with a history of borderline mucinous tumour who presented 17 months later with PPC and 21 months after with recurrent disease metastatic to the eye, and review pertinent literature.

Conclusion

High index of suspicion is warranted when patients with history of primary peritoneal carcinoma present with visual complaints in order to treat and/or relieve symptomatology from metastatic eye disease.
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In Wilson disease, mutations in the ATP7B-gene lead to hepatic accumulation of copper that becomes toxic when the hepatic binding capacity is exceeded, leading to oxidative stress and acute liver failure. Several proteins are probably involved in dealing with the excess copper and oxidative stress. As a first step towards biomarker discovery and analyzes of copper metabolism in Wilson disease patients we characterized copper-induced changes in protein expression in cell lysates and culture media from an in vitro copper-overload model using surface enhanced laser desorption/ionization (SELDI) proteomics technology. HepG2 cells were cultured for 48 h with a physiological (0.5 microM) or a pathological (100 microM) copper concentration. Samples were applied to weak cation exchange (WCX) proteinchip arrays and chips were analyzed by time of flight (TOF)-mass spectrometry. Copper-coated IMAC chips were used to detect copper-binding proteins in cell lysate of copper depleted cells using buffers with increasing imidazole concentrations. Data from the 2 to 50 kDa range indicate that high extra-cellular copper substantially altered both intra-cellular protein expression as well as the composition of the secretome. In the lysate 15 proteins were found up-regulated, while 6 proteins were down-regulated. In culture media 21 proteins were increased while 4 proteins were decreased in abundance. Copper-coated protein chips revealed the presence of 18 high-affinity copper-binding proteins. Further identification is necessary to determine the exact cellular roles of the discovered proteins.  相似文献   
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  总被引:3,自引:0,他引:3  
Custom-made zinc-finger nucleases (ZFNs) can induce targeted genome modifications with high efficiency in cell types including Drosophila, C. elegans, plants, and humans. A bottleneck in the application of ZFN technology has been the generation of highly specific engineered zinc-finger arrays. Here we describe OPEN (Oligomerized Pool ENgineering), a rapid, publicly available strategy for constructing multifinger arrays, which we show is more effective than the previously published modular assembly method. We used OPEN to construct 37 highly active ZFN pairs which induced targeted alterations with high efficiencies (1%-50%) at 11 different target sites located within three endogenous human genes (VEGF-A, HoxB13, and CFTR), an endogenous plant gene (tobacco SuRA), and a chromosomally integrated EGFP reporter gene. In summary, OPEN provides an \"open-source\" method for rapidly engineering highly active zinc-finger arrays, thereby enabling broader practice, development, and application of ZFN technology for biological research and gene therapy.  相似文献   
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