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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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A fast atom bombardment mass spectrometric protocol has been developed to determine the type of oligosaccharide chain present in glycoproteins. The procedure is based on acetolysis of the intact glycoconjugate, extraction of the peracetylated carbohydrate fragments and analysis by fast atom bombardment mass spectrometry. The molecular ions present in the FAB spectra uniquely define the composition of the oligosaccharides with respect to hexose, aminohexose and sialic acid content. High mannose oligosaccharides yield a series of peracetylated hexose oligomers whereas complex-type oligosaccharides afford a series of N-acetyl-lactosamine containing species. Fucosylation is usually not detected but sialylated oligosaccharides are readily identified and the type of sialic acid is also defined. The method has been tested on three glycoproteins of known structure - fetuin, ribonuclease B and erythrocyte Band 3 - and on a glycoprotein of unknown structure - alpha-galactosidase I, an enzyme lectin from Vicia faba. The latter is shown to contain high mannose carbohydrate chains.  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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