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61.
62.
Summary Soils from rhizosphere and non-rhizosphere of maize and mung crops and an uncultivated field were analysed for organic carbon, total nitrogen, cation exchange capacity and pH. The rhizosphere soils showed higher carbon and nitrogen content than non-rhizosphere soils. Phenolic acids viz, vanillic, p-hydroxybenzoic, p-coumaric, salicylic and syringic and pyrocatechol were detected in different cultivated and uncultivated soils. Pyrocatechol was absent from rhizosphere soils of both crops while p-coumaric and salicylic acids were not detected in rhizosphere of mung crop and nonrhizosphere of maize crop respectively. Syringic acid was present only in case of maize. Gluconic, tartaric, and citric acids were also detected in different soils. re]19720712 相似文献
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64.
Lipopolysaccharide was isolated from strain LMG 6999 of Burkholderia vietnamiensis. Degradative and NMR spectroscopic studies established the presence of two polymeric fractions based on the following trisaccharide repeating units: I: →3)-α-d-Galp-(1→3)-β-d-Galp-(1→3)-β-d-GalpNAc-(1→; II: →3)-α-d-GalpNAc-(1→3)-β-d-GalpNAc-(1→4)-α-l-Rhap-(1→.The same polymers have previously been found together in lipopolysaccharide from the reference strain for Burkholderia cepacia serogroup O4 and, individually, in those from B. cepacia serogroups C (I) and A (II). 相似文献
65.
Sandeep Kumar Gaur Krishna Kumar 《Archives Of Phytopathology And Plant Protection》2017,50(15-16):802-814
Oral administration of root extracts of a medicinal plant, Ashwagandha (Withania somnifera) to last instar larvae of a polyphagous pest, Spodoptera litura resulted into abnormal morphogenesis and the effects comprised mortality, delay in larval-pupal and pupal-adult ecdysis, ecdysial stasis, formation of larval-pupal and pupal-adult intermediates, reduced pupation and formation of abnormal pupae, complete suppression of normal adult emergence and formation of adultoids. These effects are similar to those produced by the administration of JHAs and may be due to interference with the normal hormonal mechanism of moulting and metamorphosis. 相似文献
66.
Background
Despite tremendous progress in understanding the mechanisms of constitutive and alternative splicing, an important and widespread step along the gene expression pathway, our ability to deliberately regulate gene expression at this step remains rudimentary. The present study was performed to investigate whether a theophylline-dependent "splice switch" that sequesters the branchpoint sequence (BPS) within RNA-theophylline complex can regulate alternative splicing. 相似文献67.
Allal Ouhtit Rajiv L. Gaur Zakaria Y. Abd Elmageed Augusta Fernando Rajesh Thouta Alison K. Trappey Mohamed E. Abdraboh Hassan I. El-Sayyad Prakash Rao Madhwa G.H. Raj 《生物化学与生物物理学报:癌评论》2009
CD146, also known as melanoma cell adhesion molecule or MCAM, is a key cell adhesion protein in vascular endothelial cell activity and angiogenesis. CD146 promotes tumor progression of many cancers including melanoma and prostate. Strikingly, its expression is frequently lost in breast carcinoma cells, and it may act as a suppressor of breast cancer progression. While upstream mechanisms regulating CD146 are well documented, our understanding of the downstream molecular events underlying its mode of action remains to be elucidated. This review aims to focus on the progress in understanding the signaling mechanisms and the functional relevance of CD146, a multifaceted molecule, in cancer with particular emphasis on its role in inhibiting breast cancer progression. 相似文献
68.
Kaushalaya Nandan Gaur 《Revue de Micropaléontologie》2009,52(3):227
A prolific foraminiferal assemblage comprising 51 species is reported from Jurassic sediments of the Chari Formation, Jumara Hills, Kutch, India. The assemblage is dominated by the families Vaginulinidae and Nodosariidae. Sixteen species are reported for the first time from the Indian region including one new species. The foraminiferal assemblage suggests a Callovian to Oxfordian age for the studied sequence. The depositional environment of the studied sequence is interpreted based on foraminiferal evidence combined with lithology and megafauna which indicates that the sediments of the Chari formation exposed at Jumara Hills were deposited in a shallow-water, near shore, environment with fluctuating shoreline in a tectonically unstable shelf zone. The Jumara Hills foraminiferal assemblage exhibits close affinity with certain other Jurassic assemblages of the Tethyan Realm and helped in drawing palaeogeographic conclusions, suggesting that during the Middle and Late Jurassic epochs Kutch had close sea connections with Central Arabia, Afghanistan and Rajasthan on the one hand and Somalia and Malagasy on the other. 相似文献
69.
Histopathological effects of cisplatin,doxorubicin and 5-flurouracil (5-FU) on the liver of male albino rats
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Hassan I El-Sayyad Mohamed F Ismail F M Shalaby RF Abou-El-Magd Rajiv L Gaur Augusta Fernando Madhwa HG Raj Allal Ouhtit 《International journal of biological sciences》2009,5(5):466-473
Cisplatin, doxorubicin and fluorouracil (5-FU), drugs belonging to different chemical classes, have been extensively used for chemotherapy of various cancers. Despite extensive investigations into their hepatotoxicity, there is very limited information on their effects on the structure and ultra-structure of liver cells in vivo. Here, we demonstrate for the first time, the effects of these three anticancer drugs on rat liver toxicity using both light and electron microscopy. Light microscopic observations revealed that higher doses of cisplatin and doxorubicin caused massive hepatotoxicity compared to 5-FU treatment, including dissolution of hepatic cords, focal inflammation and necrotic tissues. Interestingly, low doses also exhibited abnormal changes, including periportal fibrosis, degeneration of hepatic cords and increased apoptosis. These changes were confirmed at ultrastructural level, including vesiculated rough endoplasmic reticulum and atrophied mitochondria with ill-differentiated cisternae, dense collection of macrophages and lymphocytes as well as fibrocytes with collagenous fibrils manifesting early sign of fibrosis, especially in response to cisplatin and doxorubicin -treatment. Our results provide in vivo evidence, at ultrastructural level, of direct hepatotoxicity caused by cisplatin, doxorubicin and 5-FU at both light and electron microscopi. These results can guide the design of appropriate treatment regimen to reduce the hepatotoxic effects of these anticancer drugs. 相似文献
70.
Molecular techniques play a critical role in studies of phylogeny and, thus, have been applied to understand the distribution and extent of genetic variation within and between species. In the present study, a genetic analysis was undertaken using molecular markers (9 ISSR and 13 SSR) on 60 ginger cultivars from different regions of the eastern coast of India (Odisha). The data obtained with 22 polymorphic markers revealed moderate to high diversity in the collection. Both ISSR and SSR markers were efficient in distinguishing all the 60 ginger cultivars. A total of 42 and 160 polymorphic bands were observed with ISSR and SSR markers, respectively. However, SSR markers were observed to be better at displaying average polymorphism (63.29%) than ISSR markers (55%). Analysis of molecular variance results showed that 52 and 66% of the variation occurred among different ginger populations, whereas 48 and 34% of the variation was found within populations, respectively, using ISSR and SSR markers, indicating that ginger cultivars display significant genetic diversity at the population level. Principal coordinates analysis and the dendrogram constructed out of combined data of both markers showed grouping of ginger accessions to their respective area of collection, indicating geographical closeness due to genetic similarity irrespective of the relationship that exists at the morphological level. 相似文献