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461.
Addition of 2.5 mM vitamin C or 40 mM of glucose to washed buffalo spermatozoan suspensions in Ca2(+)-free Kreb's Ringer Hanseliet saline buffer (pH 7.0) resulted in significant lower malonaldehyde concentration and higher spermatozoan motility and liver spermatozoa compared to control levels after 45 min of aerobic incubation at 37 degrees C or pre-incubation levels. 相似文献
462.
Vitamin E significantly (P less than 0.01), inhibited lipid peroxidation as indicated by malonaldehyde (MDA) production and improved significantly (P less than 0.01) motility and percent live spermatazoa of B. bubalis semen. Bulls with higher MDA formation had lower sperm motility and percent live count. Variance due to bulls for all the three parameters were significant (P less than 0.05). 相似文献
463.
Uttam Chand Banerjee 《Biotechnology Techniques》1993,7(5):339-345
Rifamycin oxidase of Curvularia lunata was immobilized on polyacrylamide gel. The optimum pH and temperature for immobilized enzyme reaction were 6.5 and 50 °C, respectively. Enzyme stability increased on immobilization and the half lives of immobilized enzyme preparations at 30 and 40 °C were 30 and 11.5 d, respectively. With 2.5 mm beads diffusional resistances were observed. Reusability studies showed that 1 mm size beads gave a higher rate of transformation in comparison with 2 or 2.5 mm beads. 相似文献
464.
Transgenic tea [Camellia sinensis (L.) O. Kuntze cv. Kangra Jat] plants obtained by Agrobacterium-mediated transformation of somatic embryos 总被引:1,自引:0,他引:1
A protocol for the production of transgenic tea [Camellia sinensis (L.) O. Kuntze cv. Kangra Jat] was developed via Agrobacterium-mediated genetic transformation of somatic embryos. Two disarmed Agrobacterium tumefaciens strains, EHA 105 and LBA 4404, both carrying the binary plasmid p35SGUSINT with the nptII gene and gus-intron were evaluated as vector systems. A number of parameters were tested with respect to maximizing transformation efficiency. While pre-culture, wounding and acetosyringone treatment were inhibitory, the bacterial growth phase (optical density; OD600 = 0.6), cell density (109/ml), co-cultivation period (5 days) and pH of the co-cultivation medium (5.6) had positive effects on transformation. Following co-cultivation, globular somatic embryos were placed on multiplication medium and stressed with kanamycin (50 µg/ml). Further selection occurred in the maturation and germination medium at an elevated kanamycin level (75 µg/ml). An average of 40% transient expression was evident based on the GUS histochemical assay. Kanamycin-resistant, GUS-positive embryos were germinated, and the resulting microshoots were multiplied in vitro. Integration of the transgenes into the tea nuclear genome was confirmed by PCR analysis using nptII- and gus-specific primers and by Southern hybridization using an nptII-specific probe. The transgenic shoots were micrografted onto seed-grown rootstocks of cv. Kangra Jat and eventually hardened in a walk-in polyhouse. This is the first report on the production of transgenic tea. 相似文献
465.
Uttam Chand Banerjee 《Biotechnology Techniques》1993,7(10):733-738
Summary
Curvularia lunata was grown in a stirred and aerated reactor for the production of extracellular rifamycin oxidase. Volumetric oxygen transfer coefficients (KLa) were measured for various stirrer speeds, rates of aeration and cell mass concentrations in the reactor. Stirrer speed and aeration rate were optimized and it was found that stirrer speeds of 400–500 rpm and aeration rates of 0.75–1 vvm were optimum for the maximum amount of enzyme production. It was noticed that the increase in cell mass decreased the oxygen transfer coefficient. It was also noticed that the organism formed pellets rather than mycelia when grown on glucose and with an increase in the concentration of glucose in the reactor, there was heavy pellet formation. 相似文献
466.
Effect of gypsum,pressmud, fulvic acid and zinc sources on yield and zinc uptake by rice crop in a saline-sodic soil 总被引:1,自引:0,他引:1
Summary The application of fulvic acid to a saline-sodic soil augmented the solubility of zinc by thousands fold. Zinc fulvate when applied at levels equivalent to that of zinc sulphate was more effective in enhancing diffusion of zinc in the soil. Application of gypsum, zinc sulphate and fulvic acid significantly increased dry matter yield and uptake of zinc by rice crop in a saline-sodic soil. Application of gypsum with pressmud or with fulvic acid and zinc sulphate resulted in significantly higher yield and zinc uptake than in other treatments. 相似文献
467.
Debabrata Banerjee Raj Tiwari Mitali Basu Gora Chand Chatterjee 《Journal of biosciences》1983,5(1):53-62
A new bioluminescent fungal system from a wood sample with a characteristic emission around 518 ±1 nm is described. This study
indicates that water is not only important for emission but has a function in the kinetics of the reaction 相似文献
468.
Mahmoud A. Ghannoum Nancy C. Isham David V. Chand 《Current fungal infection reports》2009,3(3):142-146
The dermatophytes are a specialized group of fungi that infect the keratinized tissues of humans (hair, nails, and skin) and
cause superficial infections. Although several studies have been conducted to develop methods to determine the susceptibilities
of yeast and filamentous fungi, similar studies for dermatophytes have only recently taken place. We review how susceptibility
testing of dermatophytes was developed and how it has already been applied to clinical samples. We also review recent advances
in the development of disk diffusion and colorimetric methodologies for determining the antifungal susceptibility of dermatophytes.
With several agents now available for treating infections due to dermatophytes, susceptibility testing will serve as a valuable
tool for clinicians as they choose the most appropriate treatment option. Studies are still needed to establish interpretive
breakpoints for antifungal agents used in the treatment of superficial fungal infections. 相似文献