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1.
Phytochemical analysis of dried twigs of Marsdenia roylei (family Asclepiadaceae) has resulted in the isolation of a trisaccharide, maryal, and a diglycoside, rolinose. Their structures were determined as O-beta-D-oleandropyranosyl-(1-->4)-O-beta-D-digitoxopyranosyl++ +-(1-->4)-D- cymaral and ethyl O-beta-D-oleandropyranosyl-(1-->4)-O-3-O-methyl-6-deoxy-beta-D- allopyranoside, respectively, by chemical degradation and spectroscopic methods. 相似文献
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Composition of complex lipid of chloroplasts of two cultivars of wheat and barley was determined at tillering, ear emergence and grain filling stages. The chloroplast lipids, MGDG, DGDG and PG were maximum at grain filling stage in both wheat and barley. PC content showed variations at different stages in both the crops while no significant changes were observed in PI concentrations at grain filling stage. 相似文献
4.
Ambikesh Soni Manohar Prasad Bhandari Gagan Kant Tripathi Priyavand Bundela Pradeep Kumar Khiriya Purnima Swarup Khare Manoj Kumar Kashyap Abhijit Dey Balachandar Vellingiri Suresh Sundaramurthy Arisutha Suresh José M. Pérez de la Lastra 《Journal of cellular and molecular medicine》2023,27(6):737-762
In recent years, drug manufacturers and researchers have begun to consider the nanobiotechnology approach to improve the drug delivery system for tumour and cancer diseases. In this article, we review current strategies to improve tumour and cancer drug delivery, which mainly focuses on sustaining biocompatibility, biodistribution, and active targeting. The conventional therapy using cornerstone drugs such as fludarabine, cisplatin etoposide, and paclitaxel has its own challenges especially not being able to discriminate between tumour versus normal cells which eventually led to toxicity and side effects in the patients. In contrast to the conventional approach, nanoparticle-based drug delivery provides target-specific delivery and controlled release of the drug, which provides a better therapeutic window for treatment options by focusing on the eradication of diseased cells via active targeting and sparing normal cells via passive targeting. Additionally, treatment of tumours associated with the brain is hampered by the impermeability of the blood–brain barriers to the drugs, which eventually led to poor survival in the patients. Nanoparticle-based therapy offers superior delivery of drugs to the target by breaching the blood–brain barriers. Herein, we provide an overview of the properties of nanoparticles that are crucial for nanotechnology applications. We address the potential future applications of nanobiotechnology targeting specific or desired areas. In particular, the use of nanomaterials, biostructures, and drug delivery methods for the targeted treatment of tumours and cancer are explored. 相似文献
5.
R. S. Khare 《American anthropologist》2003,105(2):397-398
Time for Tea: Women, Labor, and Post/Colonial Politics on an Indian Plantation. Piya Chatterjee. Durham, NC: Duke University Press, 2001. 417 pp. 相似文献
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Neeru Jain Shruti Gupta Shashi B. Babbar 《Journal of plant biochemistry and biotechnology.》1997,6(2):129-131
Isubgol, the mucilaginous husk derived from the seeds of Plantago ovata, has been successfully used as a gelling agent for microbial culture media. As illustrative examples, fast growing symbiotic bacterium, Rhizobium meliloti and saprophytic fungi, Aspergillus flavus and Penicillium chrysogenum were cultured on media gelled with either Isubgol or agar. All the three microbes employed in the study exhibited normal growth when cultured on their respective media gelled with Isubgol. Rather, Isubgol gelled medium appears to promote the growth of bacterial cultures as the colonies on this medium were denser than the corresponding ones on the medium gelled with agar. Likewise, on Isubgol gelled medium, sporulation in both the fungi took place earlier than on the medium gelled with agar, thus indicating the promotive influence of the former gelling agent. 相似文献
8.
Two new pregnane ester glycosides designated as pallidine and pallidinine have been isolated from the dried twigs of Pergularia pallida. Chemical and spectroscopic evidences are consistent with the structure 12,20-di-O-benzoyl sarcostin-3-O-β-d-oleandroside and 12,20-di-O-benzoyl-sarcostin-3-O-β-d-cymaropyranosyl(1 → 4)-β-d-oleandropyranoside for pallidine and pallidinine respectively. 相似文献
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Shashi Shrivastav Yousuf Sharief John Day Charles F. Reich Robert A. Bonar 《In vitro cellular & developmental biology. Plant》1981,17(12):1117-1124
Summary A new cell line, SS78, was established from a primary renal cell carcinoma of a Caucasian male. The tissue was dispersed with
collagenase, and viable cells were separated by flotation on a Ficoll-Hypaque gradient. In culture, the SS78 cells retained
a distinct epithelial morphology, and no fibroblastlike cells were seen. The cultured cells were aneuploid with a modal chromosome
number of 80 and had several marker chromosomes. Inoculation of the cultured cells into athymic nude mice caused tumors at
the sites of inoculation.
This research was supported in part by Grants CA 15972 and CA 14930 from the National Cancer Institute through the National
Bladder Cancer Project and by the Medical Research Service of the Veterans Administration. 相似文献
10.
Two steroidal saponins, floribundasaponins A and B isolated from the yams of Dioscorea floribunda, have been characterized as pennogenin-3-O-β-d-glucopyranoside and pennogenin-3-O-α-l-rhamnopyranosyl(1→4)-β-d-glucopyranoside. 相似文献