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81.
Two new naturally occurring formylated phloroglucinol compounds (FPCs), a dimer, loxophlebal B (10) and a cyclized FPC, loxophlebene (8) together with eight other formylated phloroglucinols (1–7 and 9) were isolated from the chloroform-methanol (8:2) extract of the leaves of Eucalyptus loxophleba ssp. lissophloia. The structures of new compounds were established by comprehensive spectral analysis and by comparison of their NMR data with those of related compounds in the literature. All the isolated compounds were evaluated for anti-leishmanial activity against promastigotes of Leishmania donovani. 相似文献
82.
Singh Harpreet Brar Parkash Singh Honparkhe M. Arora A. K. Dhindsa S. S. 《Tropical animal health and production》2020,52(1):357-363
Tropical Animal Health and Production - The study evaluated the reliability of polymorphonuclear (PMN) cell count in endometrial cytology by cytobrush technique as a diagnostic for subclinical... 相似文献
83.
A George RA Shah R Sharma P Palta SK Singla RS Manik MS Chauhan 《Reproduction in domestic animals》2011,46(3):444-447
Parthenogenetic activation using zona‐free oocytes offers an alternative model that could be applied to develop protocols for the activation of reconstructed embryos for cloning. The aim of this study was to compare the efficacy of different methods for the activation of zona‐free buffalo oocytes in terms of their effects on the developmental competence of parthenogenetic embryos. The effects of zona removal on parthenogenetic activation and in vitro developmental competence of metaphase II oocytes were also examined. All activation methods were followed by incubation of 2 mm 6‐dimethylaminopurine (6‐DMAP) for 4 h. Out of three different pulse strengths (1.2, 2.1 or 3.3 kV/cm) used, 2.1 kV/cm resulted in the highest blastocyst rate (25.3%). On comparing different chemical agents and electric pulse, highest blastocyst rate was observed for calcium ionophore (CaI) (28.6%) followed by ethanol (25.0%), electric pulse (22.5%) and combined CaI and ethanol treatment (16.7%) although differences among them were not significant. Furthermore, a significantly reduced developmental potential was observed in zona‐free oocytes when compared to zona‐intact ones up to the blastocyst stage (44.3% vs 27.1%). In conclusion, zona‐free buffalo oocytes can be successfully activated for parthenogenetic development using chemical or electrical stimulation. Out of different agents examined, CaI followed by 6‐DMAP resulted in the highest blastocyst rate. 相似文献
84.
Arora RJ Bhatia S Mishra BP Jain A Prakash B 《Tropical animal health and production》2011,43(2):401-408
Information is presented on the genetic diversity and relationship among six Indian sheep breeds/populations belonging to
the Southern peninsular and Eastern agroecological zones, based on microsatellite markers. Parameters of genetic variation,
viz., allele diversity, observed heterozygosity, gene diversity and population inbreeding estimates, were calculated for the
six breeds. The allele diversity ranged from 6.40 to 7.92, whereas the gene diversity varied from 0.617 to 0.727. The highest
allele and gene diversity was observed for Nellore sheep, while the lowest was exhibited by Garole breed. Within population
inbreeding estimate (F
IS) revealed a significant deficit of heterozygotes in Deccani, Madgyal, Nellore and Garole, whereas Ganjam and Chhotanagpuri
sheep showed an excess of heterozygotes. The contribution of each breed to the total diversity of the breeds was quantified
by the Weitzman approach. The marginal loss of diversity incurred with removal of Nellore and Garole breeds was higher (>27%),
whereas removal of Deccani breed resulted in lowest loss of diversity (3.84%) from the set. Estimation of the genetic differentiation
(F
ST) and genetic distance (D
A) between the pairs of breeds revealed a close relationship between Deccani and Madgyal sheep (F
ST = 0.017; D
A = 0.080) and greatest demarcation between Madgyal and Garole breeds (F
ST = 0.110; D
A = 0.622). The information generated would help in shaping genetic management and conservation programs for the sheep breeds
under consideration. 相似文献
85.
Gowane Gopal R. Chopra Ashish Prakash Ved Arora A. L. 《Tropical animal health and production》2011,43(1):189-198
Data were collected over a period of 21 years (1988–2008) to estimate (co)variance components for birth weight (BWT), weaning
weight (WWT), 6-month weight (6WT), 9-month weight (9WT), 12-month weight (12WT), average daily gain from birth to weaning
(ADG1), weaning to 6WT (ADG2), and from 6WT to 12WT (ADG3) in Sirohi goats maintained at the Central Sheep and Wool Research
Institute, Avikanagar, Rajasthan, India. Analyses were carried out by restricted maximum likelihood, fitting six animal models
with various combinations of direct and maternal effects. The best model was chosen after testing the improvement of the log-likelihood
values. Heritability estimates for BWT, WWT, 6WT, 9WT, 12WT, ADG1, ADG2, and ADG3 were 0.39 ± 0.05, 0.09 ± 0.03, 0.06 ± 0.02,
0.09 ± 0.03, 0.11 ± 0.03, 0.10 ± 0.3, 0.04 ± 0.02, and 0.01 ± 0.01, respectively. For BWT and ADG1, only direct effects were
significant. Estimate of maternal permanent environmental effect were important for body weights from weaning to 12WT and
also for ADG2 and ADG3. However, direct maternal effects were not significant throughout. Estimate of c
2 were 0.06 ± 0.02, 0.03 ± 0.02, 0.06 ± 0.02, 0.05 ± 0.02, 0.02 ± 0.02, and 0.02 ± 0.02 for 3WT, 6WT, 9WT, 12WT, ADG2, and
ADG3, respectively. The estimated repeatabilities across years of ewe effects on kid body weights were 0.10, 0.08, 0.05, 0.08,
and 0.08 at birth, weaning, 6, 9, and 12 months of age, respectively. Results suggest possibility of modest rate of genetic
progress for body weight traits and ADG1 through selection, whereas only slow progress will be possible for post-weaning gain.
Genetic and phenotypic correlations between body weight traits were high and positive. High genetic correlation between 6WT
and 9WT suggests that selection of animals at 6 months can be carried out instead of present practice of selection at 9 months. 相似文献
86.
87.
选用地理纬度相似的中国辽宁省、美国俄亥俄州新近育成的大豆品种,分别和中国辽宁省20世纪20年代老品种进行了农艺性状的比较研究。结果表明:中美大豆品种主要农艺性状遗传改进的共有趋势是主茎荚数、单株荚数、3粒和4粒荚率、单株粒数、单株粒重、百粒重、粒茎比、收获指数明显增加。株高、主茎节数、节间长度和分枝数显著降低。美国新品种的单株荚数、单株粒数和粒茎比的增加幅度明显高于同期的中国新品种。而中国新品种的百粒重显著高于美国新品种。施肥水平对不同年代大豆品种主要农艺性状也有一定影响,且美国新品种在高肥条件下比中国新品种表现出更高的增产潜力。 相似文献
88.
Korekar G Stobdan T Arora R Yadav A Singh SB 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(4):376-383
Fourteen apricot genotypes grown under similar cultural practices in Trans-Himalayan Ladakh region were studied to find out
the influence of genotype on antioxidant capacity and total phenolic content (TPC) of apricot kernel. The kernels were found
to be rich in TPC ranging from 92.2 to 162.1 mg gallic acid equivalent/100 g. The free radical-scavenging activity in terms
of inhibitory concentration (IC50) ranged from 43.8 to 123.4 mg/ml and ferric reducing antioxidant potential (FRAP) from 154.1 to 243.6 FeSO4.7H2O μg/ml. A variation of 1–1.7 fold in total phenolic content, 1–2.8 fold in IC50 by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 1–1.6 fold in ferric reducing antioxidant potential among the examined
kernels underlines the important role played by genetic background for determining the phenolic content and antioxidant potential
of apricot kernel. A positive significant correlation between TPC and FRAP (r = 0.671) was found. No significant correlation was found between TPC and IC50; FRAP and IC50; TPC and physical properties of kernel. Principal component analysis demonstrated that genotypic effect is more pronounced
towards TPC and total antioxidant capacity (TAC) content in apricot kernel while the contribution of seed and kernel physical
properties are not highly significant. 相似文献
89.
Estimates of (co)variance components and genetic parameters were calculated for birth weight (BWT), weaning weight (WWT), 6 month weight (6WT), 9 month weight (9WT), 12 month weight (12WT) and greasy fleece weight at first clip (GFW) for Malpura sheep. Data were collected over a period of 23 years (1985–2007) for economic traits of Malpura sheep maintained at the Central Sheep & Wool Research Institute, Avikanagar, Rajasthan, India. Analyses were carried out by restricted maximum likelihood procedures (REML), fitting six animal models with various combinations of direct and maternal effects. Direct heritability estimates for BWT, WWT, 6WT, 9WT, 12WT and GFW from the best model (maternal permanent environmental effect in addition to direct additive effect) were 0.19 ± 0.04, 0.18 ± 0.04, 0.27, 0.15 ± 0.04, 0.11 ± 0.04 and 0.30 ± 0.00, respectively. Maternal effects declined as the age of the animal increased. Maternal permanent environmental effects contributed 20% of the total phenotypic variation for BWT, 5% for WWT and 4% for GFW. A moderate rate of genetic progress seems possible in Malpura sheep flock for body weight traits and fleece weight by mass selection. Direct genetic correlations between body weight traits were positive and ranged from 0.40 between BWT and 6WT to 0.96 between 9WT and 12WT. Genetic correlations of GFW with body weights were 0.06, 0.49, 0.41, 0.19 and 0.15 from birth to 12WT. The moderately positive genetic correlation between 6WT and GFW suggests that genetic gain in the first greasy fleece weight will occur if selection is carried out for higher 6WT. 相似文献
90.
Arora H Du P Tan KW Hyun JK Grazul J Xin HL Muller DA Thompson MO Wiesner U 《Science (New York, N.Y.)》2010,330(6001):214-219
Epitaxy is a widely used method to grow high-quality crystals. One of the key challenges in the field of inorganic solids is the development of epitaxial single-crystal nanostructures. We describe their formation from block copolymer self-assembly-directed nanoporous templates on single-crystal Si backfilled with Si or NiSi through a laser-induced transient melt process. Depending on thickness, template removal leaves either an array of nanopillars or porous nanostructures behind. For stoichiometric NiSi deposition, the template pores provide confinement, enabling heteroepitaxial growth. Irradiation through a mask provides access to hierarchically structured materials. These results on etchable and non-etchable materials suggest a general strategy for growing epitaxial single-crystal nanostructured thin films for fundamental studies and a wide variety of applications, including energy conversion and storage. 相似文献