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排序方式: 共有108条查询结果,搜索用时 31 毫秒
41.
Kamal K. Panda Anath B. Das Brahma B. Panda 《Genetic Resources and Crop Evolution》2009,56(5):629-637
Pandanus tectorius Parkinson (
P. fascicularis Lam.) of the family Pandanaceae constitutes one of the major bioresources of Ganjam coast, Orissa; used mainly in small scale
perfume industry for aromatic compound extracted from the male inflorescences. In order to establish genetic diversity, if
any related to perfume yield, samples of P. tectorius representing male populations from seven locations representing populations I–VII along the coastline of Orissa, India, were
analysed for somatic chromosome number, 4C genomic DNA content, randomly amplified polymorphic DNA (RAPD) as well as phytochemicals.
The somatic chromosome number in all the populations I–VII was 2n = 60. The chromosomes were of minute size without showing any remarkable structural variation. Like wise the average 4C DNA
content was 5.09 pg (≅4,912 Mbp) that showed no intra- or inter-population differences. Out of 54 decamer primers tested,
a total of 1,260 amplicons were obtained from 34 primers accounting 43.49% polymorphism. Molecular phylogenetic analysis of
the seven populations revealed two distinct branches, with populations II and III in one and the rest populations in the other
branch of the phylogenetic tree. It was important to note that the unique populations II and III confined to the Ganjam coast
of Orissa having RAPD markers: OPA 09–940 bp, OPA 09–705 bp, OPC 14–1,500 bp, OPC 14–700 bp, OPC 20–1,475 bp, OPC 20–1,350 bp,
OPC 20–920 bp and OPC 20–700 bp, were distinguished form the rest of the populations. The aforesaid populations (II and III)
are well known to produce aroma of high quality and yield, composed of primarily phenyl ethyl methyl ether (66.8–83%) and
terpinen-4-ol (5–12%) along with a number of other phyto-chemical compounds that support the flourishing perfume industry
and livelihood of the local people in the region. The findings underscored the possible role of local eco-geography in contributing
to the micro-evolution of unique high perfume yielding genotypes of P. tectorius that represented populations II and III at Ganjam coast, which were genetically distinct from the rest of the populations
revealed by RAPD analysis. 相似文献
42.
Xiaoying Zhang Ajay Bommareddy Wei Chen Michael B. Hildreth Radhey S. Kaushik David Zeman Sherief Khalifa Hesham Fahmy Chandradhar Dwivedi 《Marine drugs》2009,7(2):153-165
Sarcophine-diol (SD), one of the structural modifications of sarcophine, has shown chemopreventive effects on 12-dimethylbenz(a)anthracene-initiated and 12-O-tetradecanoylphorbol-13-acetate-promoted skin tumor development in female CD-1 mice. The objective of this study was to determine the chemopreventive effects of SD on UVB-induced skin tumor development in hairless SKH-1 mice, a model more relevant to human skin cancer, and to determine the possible mechanisms of action. Carcinogenesis was initiated and promoted by UVB radiation. Female hairless SKH-1 mice were divided into two groups having 27 mice in each group: control and SD treatment. The control group was topically treated with 100 μL acetone and SD treatment group was topically treated with SD (30 μg/100 μL in acetone) 1 hour before each UVB radiation for 32 weeks. Tumor counts were recorded on a weekly basis for 30 weeks. Effects of SD on the expression of caspases were investigated to elucidate the possible mechanism of action. The proteins from epidermal homogenates of experimental mice were used for SDS-PAGE and Western blotting using specific antibodies against caspase-3, caspase-8 and caspase-9 respectively. TUNEL assay was used for determining DNA fragmented apoptotic cells in situ. Results showed that at the end of experiment, tumor multiplicity in control and SD treatment groups was 25.8 and 16.5 tumors per mouse respectively. Furthermore, Topical treatment of SD induced DNA fragmented apoptotic cells by upgrading the expressions of cleaved caspase-3 and caspase-8. This study clearly suggested that SD could be an effective chemopreventive agent for UVB-induced skin cancer by inducing caspase dependent apoptosis. 相似文献
43.
Dibya Joshi Rama Dwivedi Satya P. Pachauri Arvind K. Shukla 《Communications in Soil Science and Plant Analysis》2017,48(8):886-897
Twenty surface (0–15 cm) samples of acidic soils were analyzed for water soluble (WS), exchangeable (EX), lead displaceable (Pb-disp.), acid soluble (AS), manganese (Mn) oxide occluded (MnOX), organically bound (OB), amorphous Fe oxide occluded (AFeOX), crystalline iron (Fe) oxide occluded (CFeOX) and residual (RES) fractions of Mn, and also for extractable Mn in some common soil extractants: (diethylenetriaminepentaacetic acid (DTPA) (pH 7.3), DTPA (pH 5.3), AB-DTPA (pH 7.6), Mehlich-3 (pH 2.0), Modified Olsen, 0.005 M calcium chloride (CaCl2), 1 M magnesium chloride (MgCl2) and ion exchange resins. The WS-Mn fraction showed a significant and positive correlation with Mn extractable in DTPA (pH 5.3) and AB-DTPA (pH 7.6), while both WS-Mn and EX-Mn fractions correlated significantly and positively with Mn concentration and uptake by maize plants grown in these soils. The AB-DTPA (pH 7.6) and DTPA (pH 5.3) appeared suitable to assess the availability of Mn in acidic soils. 相似文献
44.
S. L. Agrawal Markandey Singh Mrigank Mauli Dwivedi Kamlesh Pandey 《Fibers and Polymers》2011,12(7):864-874
Present paper deals with, improvement in ion transport property and dielectric relaxation of polyethylene oxide (PEO)-based
polymer electrolytes subsequent to dispersal of nanosized Zn-ferrite filler particles. The nanocomposite polymer electrolyte
(NCPE) system [93PEO:7NH4SCN]: x% Zn-ferrite was prepared by solution cast technique through dispersal of sol gel derived Zn-ferrite nano powder in
the pristine polymer electrolyte solution. The structural and morphological behavior of NCPEs have been studied by XRD, SEM,
IR and DSC measurements. Electrical conductivity (both a.c. & d.c.) measurement on nanocomposite polymer electrolyte sample
have been carried out using impedance spectroscopic technique. Dielectric relaxation studies were extracted by impedance data.
The hopping ion transport mechanism in NCPEs has been concluded with the help of dielectric and modulus formalism. 相似文献
45.
Polley Shamik De Sachinandan Brahma Biswajit Mukherjee Ayan P.V. Vinesh Batabyal Subhasis Arora Jaspreet Singh Pan Subhransu Samanta Ashis Kumar Datta Tirtha Kumar Goswami Surender Lal 《Tropical animal health and production》2010,42(5):985-993
Tropical Animal Health and Production - Mutation studies in different prolific sheep breeds have shown that the transforming growth factor beta super family ligands viz. the growth differentiation... 相似文献
46.
47.
Agro-morphological characterization of ovary culture-derived plants of rice (Oryza sativa L.) 总被引:2,自引:0,他引:2
Plants derived from unpollinated ovary culture of ten rice genotypes showed significant variability in agro-morphological
characteristics. The ovary-derived plant (H1) populations were completely haploid, doubled haploid or haploid-doubled haploid
mixture. Haploids had very drastic reduction in plant height, panicle length, grain length, breadth and number and spikelet
fertility (0.0%–2.1%). Doubled haploids from the hybrid of UPRI 95–121 × UPRI 95–165 were normal with fertility ranging between
69.6% and 97.7%. A genetic segregation in ratio of 1:1 was observed for five pigmentation characters in the H1 population
derived from hybrid UPRI 95–122 × UPRI 95–165. Plant height showed the largest coefficient of variability (28.5%) followed
by the number of spikelets per panicle (24.2%), number of grains per panicle (22.0%), percent seed set (9.2%) and panicle
length (9.0%). The range of variation in the H1 population from fully fertile hybrid PMS 2A (CMS) × IR 31802 (restorer) was
similar to its corresponding F2 population for plant height, spikelet fertility and number of grains/panicle. A single clone
of plants from the cultivar BG 1321 exhibited complete male sterility but normal female fertility when pollinated with other
varieties. Ovary-derived plants from the CMS lines PMS 2A and IR 58025A showed stable male sterility and those from thermosensitive
genetic male sterile line UPRI 95–140 showed thermosensitive genetic male sterility. These lines have potential in the hybrid
breeding program and are being currently exploited.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
48.
49.
Vipra Kundoor Xiaoying Zhang Sherief Khalifa Hesham Fahmy Chandradhar Dwivedi 《Marine drugs》2006,4(4):274-285
Sarcophine derivatives have been suggested to be chemopreventive in nature. One of its derivatives, Sarcotriol (ST), was investigated to study the skin cancer chemopreventive effects in female CD-1 mice. Three groups (control, promotion, initiation) of 30 female CD-1 mice each were taken. Carcinogenesis was initiated with 7, 12- dimethylbenz (a) anthracene (DMBA) and promoted with 12-O-tetradecanoylphorbol-13- acetate (TPA). One hour before treating with DMBA (200 nmol/100 μl acetone), control and promotion groups were treated with acetone (100 μl) and initiation group with ST (30μg/100μl of acetone). Beginning one week after initiation with DMBA, control and initiation groups were treated with acetone and promotion group with ST (30μg/100μl of acetone), one hour before treating with TPA (5 nmol/100 μl acetone). This was carried out twice a week for the next 20 weeks. The effects of ST on 3H-thymidine incorporation in epidermal DNA, the possible role of apoptotic proteins and COX-2 involved in the prevention of skin tumor development of CD-1 mice were investigated. Tumor incidence and multiplicity was found to be 100%, 73%, 100% and 8.2, 4.8, 9.7 in control, promotion and initiation groups respectively. ST treatment resulted in a significant (P < 0.05) inhibition in the incorporation of 3H-thymidine in epidermal DNA. The promotion group showed higher levels of caspase-3, -8 and –9 compared to the control. COX-2 expression was significantly lower (P < 0.05) in the promotion group as compared to the control. No significant difference in caspase-3, -8, -9 and COX-2 levels were observed in the initiation group compared to control. Together, this study confirms the chemopreventive effects of ST, and for the first time identifies the stage of carcinogenesis at which ST exerts its chemopreventive effect, and elucidates the mechanism possibly by inducing apoptosis and decreasing the COX-2 levels, contributing to its overall cancer chemopreventive effects in the mouse skin cancer model. 相似文献
50.