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1.
Summary As a part of integrated study of makhana, the mineral contents of the plant parts and the fruits of makhana (Euryale ferox) have been presented here. It has been observed that the fruits were not only rich in minerals but also in protein. The plant parts also contained high amounts of micronutrients. Its fruits are, therefore, a good supplement for minerals which are produced from otherwise agriculturally waste (water-logged) areas.  相似文献   
2.
Callus cultures were established from stem explants of Ruscus hypophyllum on a modified basal medium of Murashige and Skoog (1962) supplemented with 1 mg l-1 2,4-D+0.1 mg l-1 BAP. The optimal 2,4-D concentration for promoting shoot bud formation and growth was 0.05 mg l-1 along with 0.5 mg l-1 BAP. Sixty percent of rootless shoots produced flowers on the regenerating medium. Rooting was induced when shoots were transferred to half strength MS inorganic salts supplemented with 2 mg l-1 IBA. Eighty percent of plants transferred to soil have survived.  相似文献   
3.
The culture for 7 days in medium with 5.5 mM glucose and 1 mM 2-deoxy-D-glucose enhanced the glucose sensitivity of neonatal rat B cells, and even stimulated their growth in vitro. Also, 2-deoxy-D-glucose supplementation maintained insulin release evoked by leucine and 2-ketoisocaproate from B cells at day 7 at levels several times higher than at day 1. The effect of leucine was greatly augmented by glutamine, whereas that of the 2-keto acid remained almost unchanged irrespective of the presence of glutamine. These results suggest an increase in oxidative catabolism of medium nutrients in B cells grown in medium with 2-deoxy-D-glucose for 7 days, and such metabolic changes may promote the growth of B cells in vitro.  相似文献   
4.
T. B. Jha  S. C. Roy 《Protoplasma》1979,101(1-2):139-142
Summary Protoplasts were isolated for the first time from cell suspensions ofNigella sativa. These were then cultured in media and observed at regular intervals. Different concentrations of auxin and kinetin were tried with success to obtain root from the callus tissues of the protoplasts.  相似文献   
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6.
Cytokinesis in many eukaryotes requires an actomyosin contractile ring. Here, we show that in fission yeast the myosin-II heavy chain Myo2 initially accumulates at the division site via its COOH-terminal 134 amino acids independently of F-actin. The COOH-terminal region can access to the division site at early G2, whereas intact Myo2 does so at early mitosis. Ser1444 in the Myo2 COOH-terminal region is a phosphorylation site that is dephosphorylated during early mitosis. Myo2 S1444A prematurely accumulates at the future division site and promotes formation of an F-actin ring even during interphase. The accumulation of Myo2 requires the anillin homologue Mid1 that functions in proper ring placement. Myo2 interacts with Mid1 in cell lysates, and this interaction is inhibited by an S1444D mutation in Myo2. Our results suggest that dephosphorylation of Myo2 liberates the COOH-terminal region from an intramolecular inhibition. Subsequently, dephosphorylated Myo2 is anchored by Mid1 at the medial cortex and promotes the ring assembly in cooperation with F-actin.  相似文献   
7.
An exopolysaccharide producing marine bacterium, Enterobacter cloacae, was isolated from marine sediment collected from Gujarat coast, India. Chemical investigation of exopolysaccharide (EPS 71 a) revealed that this exopolysaccharide was an acidic polysaccliaride containing high amount of uronic acid, fucose and sulfate which is rare for bacterial exopolysaccharides. EPS 71a was found to have fucose, galactose, glucose and glucuronic acid in a molar ratio of 2: 1: 1: 1.  相似文献   
8.
Pollination services are increasingly threatened by the loss and modification of natural habitats, posing a risk to the maintenance of both native plant biodiversity and agricultural production. In order to safeguard pollination services, it is essential to examine the impacts of habitat degradation on the population dynamics of key pollinators and identify potential “rescue pollinators” capable of persisting in these human-altered landscapes. Using a landscape genetic approach, we assessed the impact of landscape structure on genetic differentiation in the widely-distributed tropical stingless bee Trigona spinipes (Apidae: Meliponini) across agricultural landscape mosaics composed of coffee plantations and Atlantic forest fragments in southeastern Brazil. We genotyped 115 bees at 16 specific and highly polymorphic microsatellite loci, developed using next-generation sequencing. Our results reveal that T. spinipes is capable of dispersing across remarkably long distances, as we did not find genetic differentiation across a 200 km range, nor fine-scale spatial genetic structure. Furthermore, gene flow was not affected by forest cover, land cover, or elevation, indicating that reproductive individuals are able to disperse well through agricultural landscapes and across altitudinal gradients. We also found evidence of a recent population expansion, suggesting that this opportunistic stingless bee is capable of colonizing degraded habitats. Our results thus suggest that T. spinipes can persist in heavily-altered landscapes and can be regarded as a rescue pollinator, potentially compensating for the decline of other native pollinators in degraded tropical landscapes.  相似文献   
9.
Large‐scale conversion of traditional agricultural cropping systems to biofuel cropping systems is predicted to have significant impact on the hydrologic cycle. Changes in the hydrologic cycle lead to changes in rainfall and its erosive power, and consequently soil erosion that will have onsite impacts on soil quality and crop productivity, and offsite impacts on water quality and quantity. We examine regional change in rainfall erosivity and soil erosion resulting from biofuel policy‐induced land use/land cover (LULC) change. Regional climate is simulated under current and biofuel LULC scenarios for the period 1979–2004 using the Weather Research Forecast (WRF) model coupled to the NOAH land surface model. The magnitude of change in rainfall erosivity under the biofuel scenario is 1.5–3 times higher than the change in total annual rainfall. Over most of the conterminous United States (~56%), the magnitude of the change in erosivity is between ?2.5% and +2.5%. A decrease in erosivity of magnitude 2.5–10% is predicted over 23% of the area, whereas an increase of the same magnitude is predicted over 14% of the area. Corresponding to the changes in rainfall erosivity and crop cover, a decrease in soil loss is predicted over 60% of the area under the biofuel scenario. In Kansas and Oklahoma, the states in which a large fraction of land area is planted with switchgrass under the biofuel scenario, soil loss is estimated to decrease 12% relative to the baseline. This reduction in soil loss is due more to changes in the crop cover factor than changes in rainfall or rainfall erosivity. This indicates that the changes in LULC, due to future cellulosic biofuel feedstock production, can have significant implications for regional soil and water resources in the United States and we recommend detailed investigation of the trade‐offs between land use and management options.  相似文献   
10.
International Journal of Peptide Research and Therapeutics - Candida albicans is the most common nosocomial systemic fungal infections causing high mortality/morbidity. Existing antifungal...  相似文献   
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