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Effect of season, media type, carbon source, growth regulators and transplanting media on micropropagation of Dendrocalamus asper, an important bamboo species, was examined. The season of explant collection played an important role in axillary bud sprouting and spring (February?CApril) was found to be the best period for explant collection. Among the different media MS was found to be the best for micropropagation. Maximum numbers (4.83/explant) of shoots were initiated in MS?+?15???M BAP. For shoot multiplication, MS medium supplemented with 10???M BAP and 75???M Adenine sulfate was used. BAP was superior to KIN for both explant establishment, as well as, shoot multiplication. Optimal rooting was achieved in shoots cultured on ? strength MS medium supplemented with 5???M each of IBA and NAA. Regenerated plantlets were acclimatized and hardened in green house using dune sand and vermi-compost (3:1) with 92.34% success and transferred to the field with 100% survival rate. In the field, plants supplied with FYM along with urea showed better growth and development. Macroproliferation, plant multiplication by separating the rooted tillers of well established in vitro raised plantlets after 5 to 6?months of growth in the green house could double the multiplication rate. More than 25000 in vitro raised plants were successfully transferred to the field and no morphological variations in growth were observed, thus proving the potential of tissue culture for raising large scale plantations of D. asper.  相似文献   
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Fourier transform infrared (FTIR) spectroscopic imaging is an emerging microscopy modality for clinical histopathologic diagnoses as well as for biomedical research. Spectral data recorded in this modality are indicative of the underlying, spatially resolved biochemical composition but need computerized algorithms to digitally recognize and transform this information to a diagnostic tool to identify cancer or other physiologic conditions. Statistical pattern recognition forms the backbone of these recognition protocols and can be used for highly accurate results. Aided by biochemical correlations with normal and diseased states and the power of modern computer-aided pattern recognition, this approach is capable of combating many standing questions of traditional histology-based diagnosis models. For example, a simple diagnostic test can be developed to determine cell types in tissue. As a more advanced application, IR spectral data can be integrated with patient information to predict risk of cancer, providing a potential road to precision medicine and personalized care in cancer treatment. The IR imaging approach can be implemented to complement conventional diagnoses, as the samples remain unperturbed and are not destroyed. Despite high potential and utility of this approach, clinical implementation has not yet been achieved due to practical hurdles like speed of data acquisition and lack of optimized computational procedures for extracting clinically actionable information rapidly. The latter problem has been addressed by developing highly efficient ways to process IR imaging data but remains one that has considerable scope for progress. Here, we summarize the major issues and provide practical considerations in implementing a modified Bayesian classification protocol for digital molecular pathology. We hope to familiarize readers with analysis methods in IR imaging data and enable researchers to develop methods that can lead to the use of this promising technique for digital diagnosis of cancer.  相似文献   
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A viable option for increasing nitrogen (N) use efficiency and mitigation of negative impacts of N on the environment is to capitalize on multi-element interactions through implementation of nutrient management programs that provide balanced nutrition. Numerous studies have demonstrated the immediate efficacy of this approach in the developing regions like China and India as well as developed countries in North America. Based on 241 site-years of experiments in these countries, the first-year N recovery efficiency (RE) for the conventional or check treatments averaged 21% while the balanced treatments averaged 54% RE, for an average increase of 33% in RE due to balanced nutrition. Effective policies to promote adoption are most likely those that enable site-specific approaches to nutrient management decisions rather than sweeping, nation-wide incentives supporting one nutrient over another. Local farmers, advisers and officials need to be empowered with tools and information to help them define necessary changes in practices to create more balanced nutrient management.

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We reviewed records of all persons dying between 1979 and 1986 in eight California institutions for the mentally retarded. Autopsies had been done in 71% of the 1,181 deaths. Nine deaths were due to hepatocellular carcinoma, which invariably developed in carriers of hepatitis B surface antigen (HBsAg) and was fatal within four months of diagnosis. The mean age at death was 32.7 years. The incidence of hepatocellular carcinoma in HBsAg carriers was 140 times greater than in the US population. Persistent hepatitis B infection was probably etiologically related to hepatocellular carcinoma in this population, which is relatively free of exposure to other hepatocarcinogens.  相似文献   
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Summary Dynamics of F-actin organization during activation and germination ofPyrus communis (pear) pollen was examined using rhodaminephalloidin. Prior to activation, the rhodamine-phalloidin labelling pattern appeared as circular profiles in the peripheral cytoplasm of the vegetative cell and as coarse granules around the vegetative nucleus. In activated pollen, parallel arrays of cortical F-actin were aligned circumferentially, along the polar axis in non-apertural areas of the pollen grain, and at 45° to 90° to the polar axis beneath the apertures. Some pollen also showed fluorescent granules or fusiform bodies dispersed throughout the cytoplasm, but as the number of such pollen diminished with prolonged incubation, these are being considered as intermediate patterns. In later stages, the filaments became organized as interapertural bundles traversing the three apertures. However, prior to emergence of the pollen tube, labelling became confined to a single aperture. In germinated pollen grains, actin microfilaments are aligned more or less axially with respect to the axis of the developing pollen tube.The granular labelling pattern seen around the vegetative nucleus prior to pollen activation also became clearly filamentous with pollen activation; this filamentous pattern persisted until germination when it was replaced by cables that aligned longitudinally with respect to the emerging tube axis.The results demonstrate that the organization of actin undergoes considerable changes in the period preceding pollen germination and that microfilament polarization is achieved before pollen germination.  相似文献   
7.
Anabaena sp. grew with mono- and di-ester phosphate compounds as sources of phosphate, indicating the presence of phosphomonoesterase (PMEase) and phosphodiesterase (PDEase) activities. Cell-bound PMEase and PDEase activities were detected during growth in 0.5 and 10 mg PO4l–1 only when the cellular phosphate concentration fell to 0.46% of cell protein and the activities increased as cellular phosphate content decreased. The Km values for these enzymes were 0.3mm forp-nitrophenyl phosphate and 0.2mm for bis-p-nitrophenyl phosphate, respectively. Only PMEase activity was found extracellularly. The pH optima for PMEase and PDEase were 10.2 and 10.4, respectively, and the temperature optima at pH 10.2 were 37°C and 40°C, respectively. Ca2+ increased the enzyme activities while Zn2+ caused marked inhibition. The inorganic phosphate repressed the cellular PMEase activity after a lag of 4 h.  相似文献   
8.
In situ digestion of metaphase and polytene chromosomes and of interphase nuclei in different cell types ofDrosophila nasuta with restriction enzymes revealed that enzymes like AluI, EcoRI, HaeIII, Sau3a and SinI did not affect Giemsa-stainability of heterochromatin while that of euchromatin was significantly reduced; TaqI and SalI digested both heterochromatin and euchromatin in mitotic chromosomes. Digestion of genomic DNA with AluI, EcoRI, HaeIII, Sau3a and KpnI left a 23 kb DNA band undigested in agarose gels while withTaqI, no such undigested band was seen. TheAluI resistant 23 kb DNA hybridized insitu specifically with the heterochromatic chromocentre. It appears that the digestibility of heterochromatin region in genome ofDrosophila nasuta with the tested restriction enzymes is dependent on the availability of their recognition sites.  相似文献   
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Bacillus megaterium cells from various growth phases were equally susceptible to the lethal effects of aflatoxin B1. Known surfactants (EDTA and Tween-80) accentuated the effects of aflatoxin B1. Viability and inulin uptake in aflatoxin B1-exposed cells decreased considerably. The effect was concentration dependent. A straight-line relationship observed in the death curve indicated a single target for aflatoxin B1 action in B. megaterium. Leakage of intracellular constituents in B. megaterium was also concentration dependent, and this can be related to the extent of cell membrane damage.  相似文献   
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