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991.
Apple shoots were grown in a Murashige and Skoog liquid proliferation medium containing 4.4 10 -6 M BA, and supplemented with various fractions of agar. Hydrolysed agar from Difco was able to overcome hyperhydricity when its concentration was increased to 0.7%. Among the fractions isolated from this hydrolysed agar, only oligosaccharides were found to reduce the occurrence of this developmental abnormality. The most anti-hyperhydric fraction had a molecular weight slightly less than 1900 daltons and contained methylated and sulphated galactose derivatives. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
992.
Procedures are given on how to prepare alginate- and gelatin-bound moist foods for exhibit fishes. Fish meal is the principal nutrient source; no fresh ingredients are used. The liquid portion can be seawater, distilled water. NaCl dissolved in distilled water, or canned clam juice, depending on whether the fishes to be fed are freshwater or seawater. Proximate analysis of the foods is provided on both a moist (ready-to-feed) and dry (desiccated) basis.  相似文献   
993.
Polyelectrolytes from seaweeds   总被引:2,自引:2,他引:0  
Smidsrød  Olav  Grasdalen  Hans 《Hydrobiologia》1984,116(1):19-28
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994.
Tryporaastogotes of three strains of Trypanosoma cruzi were isolated from the blood of infected mice employing lymphoprep for separation of the red blood cells and a column of DEAE cellulose for removal of white cells and platelets. An average recovery of 45 to 5 8 percent of actively motile, infective organisms, free of contaminating blood cells was obtained. Protein and carbohydrate assays of the separated organisms revealed significant differences between the Tulahuen, a reticulotropic strain, and the House 510 and House 11, two myotropic strains of this parasitic species. The present procedure should provide sufficient parasites for physiological and biochemical studies; it has also served to indicate particular strain characteristics which may aid in a taxonomic classification of these organisms.  相似文献   
995.
Cancer survivorship rates have drastically increased due to improved efficacy of oncologic treatments. Consequently, clinical concerns have shifted from solely focusing on survival to quality of life, with fertility preservation as an important consideration. Among fertility preservation strategies for female patients, ovarian tissue cryopreservation and subsequent reimplantation has been the only clinical option available to cancer survivors with cryopreserved tissue. However, follicle atresia after transplantation and risk of reintroducing malignant cells have prevented this procedure from becoming widely adopted in clinics. Herein, we investigated the encapsulation of ovarian follicles in alginate hydrogels that isolate the graft from the host, yet allows for maturation after transplantation at a heterotopic (i.e., subcutaneous) site, a process we termed in vivo follicle maturation. Survival of multiple follicle populations was confirmed via histology, with the notable development of the antral follicles. Collected oocytes (63%) exhibited polar body extrusion and were fertilized by intracytoplasmic sperm injection and standard in vitro fertilization procedures. Successfully fertilized oocytes developed to the pronucleus (14%), two‐cell (36%), and four‐cell (7%) stages. Furthermore, ovarian follicles cotransplanted with metastatic breast cancer cells within the hydrogels allowed for retrieval of the follicles, and no mice developed tumors after removal of the implant, confirming that the hydrogel prevented seeding of disease within the host. Collectively, these findings demonstrate a viable option for safe use of potentially cancer‐laden ovarian donor tissue for in vivo follicle maturation within a retrievable hydrogel and subsequent oocyte collection. Ultimately, this technology may provide novel options to preserve fertility for young female patients with cancer.  相似文献   
996.
The indigenous bacteria Bacillus sp. CFR1601 produced significant levels of endo-mannanase when grown on agro-wastes, namely, green gram husk and sunflower oil cake (25.6 IU/mL), used as sole carbon and nitrogen sources, respectively. Under immobilized cell system, synthetic supports (polyurethane foam, scotch brite, polyester; up to 33.2 IU/mL) were found marginally superior as compared to natural supports (cotton and silk; up to 28.2 IU/mL) for endo-mannanase production. Cooperative interactions between L-lysine HCl (0.3% w/v), Tween 60 (0.3% v/v), and sunflower oil cake (3.0% w/v) in central composite design response surface methodology ameliorated (1.61-fold) endo-mannanase titers to 48.0 IU/mL. Partially purified endo-mannanase was tested for its ability to produce oligosaccharides from guar gum. These oligosaccharides were tested in vitro for their ability to promote growth of Lactobacillus plantarum MTCC 5422 and Lactobacillus salivarius CHS 1E. Results indicated that low-molecular-weight degraded products from guar gum were (1) able to support the growth of tested strains [increased O.D600nm up to 2.3-fold and decrease in pH (<6.3) due to production of short chain fatty acid (SCFA)] when used as sole carbon source; and (2) after purification and analysis by electron spray ionization–mass spectrometry (ESI-MS) were found to be composed of mainly disaccharide and tetrasaccharide. The compatibility of endo-mannanase with various detergents together with wash performance test confirmed its potential applicability for laundry industry.  相似文献   
997.
In this study, the effect of Bacillus amyloliquefaciens-produced β-mannanase on the nutrient diffusion (release) and antioxidant activity of spent brewer yeast (SBY) was investigated. Three pretreatments were performed: (1) autolysis at 50°C for 24?h; (2) autolysis at 50°C for 24?h, with the addition of β-mannanase during the autolysis; (3) autolysis at 50°C for 24?h, and the β-mannanase was added for another 12?h treatment. The pretreatments with the addition of β-mannanase caused significant cell wall degradation, markedly increased the yield of SBY extracts. More importantly, this study found that polysaccharides were degraded to be oligosaccharides with a considerable reduction in molecular weights. Meanwhile, pretreatment with the enzyme also exhibited a higher antioxidant activity in SBY extract compared to autolysis itself. The current study indicated that pretreatment (3) had a better effect than pretreatment (2) in terms of improving in antioxidant activity in SBY extract. These improved characteristics of SBY extracts isolated through enzymatic treatment appear to show promising features for their prospective use as natural functional agents.  相似文献   
998.
Carbohydrate Accumulation in Siberian Spruce Needles of Various Ages   总被引:1,自引:0,他引:1  
The content of mono- and oligosaccharides, hemicelluloses, and water-soluble polysaccharides was studied in Siberian spruce (Picea obovata Ledeb.) needles of various ages. Accumulation of carbohydrates during the growth period and the ratio of their individual fractions were determined by the proportions between the growth rate and assimilate export in developing needles. Throughout the growth period, the content of monosaccharides in needles of all ages was much higher than that of oligosaccharides. Unlike the period of active growth, the dormancy period was characterized by a wider diversity of oligosaccharides and their rather high content. Hemicelluloses that accumulated during the previous growth season and water-soluble polysaccharides of 2- and 3-year-old needles were involved into metabolism at the time of active growth of current-year needles. Analysis of carbohydrate accumulation in 1- to 9-year-old needles showed that the monosaccharide concentration was higher in needles of the first two years. The content of hemicelluloses A and B and water-soluble polysaccharides was higher in older needles. During the growth period, the assimilates of 2- and 3-year-old needles were partly used for the formation of young needles. The increase in relative content of polysaccharides during needle senescence reflects the involvement of photosynthetic products into the secondary pool of carbon metabolites.  相似文献   
999.
母乳中存在的人乳寡糖(HMOs)是一类结构高度复杂的低聚糖,对婴儿的肠道菌群、免疫屏障、大脑发育发挥积极作用。由于母乳中基质复杂,寡糖的种类繁多,丰度跨度大,存在众多异构体,这都使得检测面临诸多挑战。现已有多种技术用于HMOs的分析,发现了200多种HMOs,液相色谱和毛细管电泳在分离HMOs方面效果显著,核磁共振、质谱、红外多光子解离光谱推动了对HMOs结构的全面解析。本文回顾了对HMOs实现高灵敏度和高特异性分析的多种技术方法,比较了不同技术的优缺点,还重点介绍了质谱以及不同技术联用在推动HMOs解析和测定方面的突破,为探究寡糖的结构-功能关系、深入理解HMOs的生物学功能提供了全面的技术支持。  相似文献   
1000.
Investigation on seasonal variation in size and chemical constituents of Sargassum sinicola Setchell et Gardner from Bahía de La Paz, Baja California Sur, Mexico, was carried out from a control bed and compared with an experimental bed with artificial nutrients added. No significant differences were found between the control and experimental thalli for size or chemical composition, except for iodine and raw fiber. For control thalli the results were: size 7.5–56.0 cm, alginate yield 7.2–13.7%, viscosity 58.7–191.7 millipascal seconds (mPa s), mannitol 2.9–8.1%, raw fiber 5.5–7.5% and iodine 0.020–0.141%; while in the experimental thalli the size ranged from 7.5 to 80.3 cm and the alginate yield was 7.8–10.4%, viscosity 41.4–163.4 mPa s, mannitol 2.9–8.3%, raw fiber 5.9–10.7% and iodine 0.021–0.098%. These variations were related to its natural growth cycle, and showed reductions during the senescence period. Results suggest that S. sinicola is not affected by relatively low nutrient concentrations, and could be considered as raw material for alginate production.  相似文献   
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