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排序方式: 共有378条查询结果,搜索用时 0 毫秒
371.
372.
Mary Babu Padma Bai Vasanthy Narayanaswami K. Lalitha Joseph K. Thomas 《Biological trace element research》1986,10(4):317-325
The effect of selenium (Se) on collagen characteristics and glutathione peroxidase (GSH-Px) activity in the skin of Japanese
quailsCoturnix coturnix japonica fed a formulated, semipurified, low-Se diet (basal) (0.05 ppm) was investigated. The quails exhibited severe Se-deficiency
symptoms and significant reduction in skin GSH-Px activity at the end of 30 d. Selenium supplementation at a 2-ppm level restored
the normal skin conditions and enhanced skin GSH-Px activity significantly. But a dietary Se level of 0.1 ppm was found to
be inadequate in restoring the general skin conditions and GSH-Px activity. A markedly low total collagen content of about
23% was observed in the skin of quails fed the basal diet, compared to 39% of total collagen content in the skin of the 2-ppm
Se-supplemented group. Molecular organization of skin collagen of quails on the basal and 0.1-ppm Se diet showed an abundance
of monomeric forms with less crosslinks, compared to the presence of polymeric forms with more crosslinks, indicating enhanced
stability in the skin collagen of quails on the 2-ppm diet. The delay in the in vitro fibril formation of collagen from the
basal and 0.1-ppm Se groups, compared to a relatively faster rate in the case of the 2-ppm Se group, indicates a disturbance
in the aggregation phenomenon of collagen. The increase in skin GSH-Px activity and concurrent increase in polymeric collagen
on increasing the dietary Se level suggest a possible role for Se in collagen metabolism. 相似文献
373.
G. M. Reddy A. Padma 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1976,47(3):115-118
Summary The allelic nature of five dwarfs (d6, d7, d8, d9 and d10), recovered in M2 after ethyl methanesulphonate treatment of a local rice variety Tellakattera, was studied in relation to the Dee-geo-woo-gen (DGWG) dwarfing gene. The behaviour of the different crosses of the dwarfs with DGWG in F1 and the segregation pattern in F2 clearly demonstrate that these induced dwarfs are non-allelic to the DGWG dwarfing gene. In view of the extensive use of this gene in developing most of the high yielding rice varieties, the new dwarfing genes of Tellakattera may be exploited as alternative sources, to avoid genetic vulnerability. 相似文献
374.
Noah Steinfeld Vikramjit Lahiri Anna Morrison Shree Padma Metur Daniel J. Klionsky Lois S. Weisman 《Molecular biology of the cell》2021,32(2):143
Phosphoinositide signaling lipids are essential for several cellular processes. The requirement for a phosphoinositide is conventionally studied by depleting the corresponding lipid kinase. However, there are very few reports on the impact of elevating phosphoinositides. That phosphoinositides are dynamically elevated in response to stimuli suggests that, in addition to being required, phosphoinositides drive downstream pathways. To test this hypothesis, we elevated the levels of phosphatidylinositol-3-phosphate (PI3P) by generating hyperactive alleles of the yeast phosphatidylinositol 3-kinase, Vps34. We find that hyperactive Vps34 drives certain pathways, including phosphatidylinositol-3,5-bisphosphate synthesis and retrograde transport from the vacuole. This demonstrates that PI3P is rate limiting in some pathways. Interestingly, hyperactive Vps34 does not affect endosomal sorting complexes required for transport (ESCRT) function. Thus, elevating PI3P does not always increase the rate of PI3P-dependent pathways. Elevating PI3P can also delay a pathway. Elevating PI3P slowed late steps in autophagy, in part by delaying the disassembly of autophagy proteins from mature autophagosomes as well as delaying fusion of autophagosomes with the vacuole. This latter defect is likely due to a more general defect in vacuole fusion, as assessed by changes in vacuole morphology. These studies suggest that stimulus-induced elevation of phosphoinositides provides a way for these stimuli to selectively regulate downstream processes. 相似文献
375.
A Baldini N Archidiacono R Carbone A Bolino V Shridhar O J Miller D A Miller D C Ward M Rocchi 《Cytogenetics and cell genetics》1992,59(1):12-16
We have isolated and characterized a human genomic DNA clone (PZ20, locus D20Z2) that identifies, under high-stringency hybridization conditions, an alphoid DNA subset specific for chromosome 20. The specificity was determined using fluorescence in situ hybridization. Sequence analysis confirmed our previously reported data on the great similarity between the chromosome 20 and chromosome 2 alphoid subsets. Comparative mapping of pZ20 on chimpanzee and gorilla chromosomes, also performed under high-stringency conditions, indicates that the alphoid subset has ancestral sequences on chimpanzee chromosome 11 and gorilla chromosome 19. However, no hybridization was observed to chromosomes 21 in the great apes, the homolog of human chromosome 20. 相似文献
376.
Sudheer Reddy V. Reddy N. Rajashekar Reddy A. Venkatram Padma M. Reddy L. Krishnakanth 《Russian Journal of Bioorganic Chemistry》2022,48(3):643-650
Russian Journal of Bioorganic Chemistry - Here we reported the synthesis of N-substituted imidazole derivatives (VIa–o) that involves Suzuki coupling reaction between... 相似文献
377.
378.
Ashok Marwah Padma Marwah Henry Lardy 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,757(2)
A simple and fast yet highly sensitive and specific method based on HPLC coupled to electrospray ionization mass spectrometry has been developed for the quantitation of corticosterone in rat plasma. After extraction of rat plasma (100 μl) with diethyl ether using 5-pregnen-3β-ol-20-one-16α-carbonitrile (Sigma) as internal standard, HPLC was performed on a short C8 column (Zorbax-Eclipse, 50×4.6 mm I.D.) using a steep methanol–water gradient (methanol 54% to 90% in 6 min). Detection was performed on a single quadruple mass spectrometer in selected ion monitoring mode (m/z 369 for corticosterone and 364 for the internal standard). The detection limit of the assay was 9 fmol (3 pg) of corticosterone on column. In vitro data were subjected to curve fitting (cubic, r2=0.9999). Recovery of corticosterone after extraction ranged from 81 to 93%. The relative standard deviations for intra- and inter-assay precision ranged from 0.8 to 3.6% and 5.2 to 12.9%, respectively. Corticosterone did not undergo any appreciable degradation when stored in plasma at −20°C for 2 months. The assay is routinely used in our laboratory to examine corticosterone levels as a marker of stress in rats and may also be used for the determination of 18-hydroxy-11-deoxycorticosterone. 相似文献