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Minerals can enter the food chain through industrial and mining activities. Soil-to-vegetable transfer is higher than soil-to-cereal, but human consumption of metals is attributable to balanced diets containing both vegetables and cereals and drinking water. However, the impact of location on intakes of metals from predominantly cereal-based Indian diets is not clear. Hence, the present study was undertaken in selected Agricultural, Industrial, and Coal Mining Areas (AA, IA, CMA) around the Allahabad District in Northern India to compare transfer of toxic metals, Pb, Cd, Cr and essential metals, Fe, Zn, Cu, Co in soil and water to common crops: cereals (rice, wheat, maize) and vegetables (spinach, potato), and to assess Daily Intake of Metal (DIM) and consequent Health Risk Index (HRI). The overall content of all metals, except Cu, in water, soils, and crops followed the pattern CMA > IA > AA. Transfer factors (TFs) followed the sequence spinach > potato > cereals. Quantitatively, however, cereals contribute maximally to a balanced diet, so DIM and HRI were higher from cereals than vegetables. Even though spinach had the highest TFs, cereals contributed maximally to HRI. CMA had the highest metal content so locally grown cereals contributed significantly to intake of both toxic and essential metals. 相似文献
94.
禽流感抗原基因NA,HA的克隆及其表达载体的构建 总被引:1,自引:0,他引:1
HA和NA是禽流感病毒重要的保护性抗原基因,为了得到禽流感植物疫苗,本试验采用高保真PCR扩增方法得到目的基因,分别克隆到pMD18-T载体.经测序证实核酸序列正确后,克隆到含有GUS基因的高效植物双元表达载体pB1121上,获得含有HA/NA基因的植物双元表达载体pB1121-HA和pB1121-NA,采用冻融法将含HA/NA基因的植物双元表达载体转入根癌农杆菌LBA4404,菌液浸染生菜子叶,共培48小时后进行GUS基因表达检测,x-glue染色显蓝色,说明带有HA/NA的植物双元表达载体构建成功,为下一步的生菜转HA/NA基因研究奠定基础. 相似文献
95.
Phylogeny of the M superhaplogroup inferred from complete mitochondrial genome sequence of Indian specific lineages 下载免费PDF全文
Revathi Rajkumar Jheelam Banerjee Hima Bindu Gunturi R Trivedi VK Kashyap 《Genome biology》2004,6(2):P3
Background
Phylogenetic analysis of human complete mitochondrial DNA sequences has largely contributed to resolving phylogenies and antiquity of different lineages belonging to the majorhaplogroups L, N and M (East-Asian lineages). In the absence of whole mtDNA sequence information of M lineages reported in India that exhibits highest diversity within the sub-continent, the present study was undertaken to provide a detailed analysis of this haplogroup to precisely characterize the lineages and unravel their intricate phylogeny. 相似文献96.
Alam SI Agarwal GS Kamboj DV Rai GP Singh L 《Indian journal of experimental biology》2003,41(2):177-180
A sensitive PCR based detection of Bacillus anthracis spores from environnment was standardized. Specific 1247bp amplicon could be detected with template concentration as low as 13 pg. Sensitivity was enhanced to 10 fold by nesting with second set of primers, forming 208bp amplicon. Extraction of DNA from spores purified from soil samples by aqueous polymer two-phase system followed by partial germination and freeze-thaw treatment yielded best results. Soil sample spiked with spores (8x10(2)/g of sample) could be detected with this method. 相似文献
97.
Exogenous abscisic acid (ABA) inhibited the germination of B. juncea seeds in a concentration dependent manner. As revealed in a time-course study, the ABA-induced inhibition got progressively alleviated with the lapse of time following ABA treatment possibly due to metabolic conversion of applied ABA in the seed tissue. A simultaneous application of certain phenolic compounds namely, p-coumaric-, vanillic-, gallic-, and chlorogenic acid (but not caffeic acid) also caused an alleviation of ABA effect. Of the above two patterns of recovery, the phenolic-dependent alleviation of ABA effect was apparent much earlier (24-48 hr treatment) than the time-dependent one (72 hr). It is likely that phenolics could accelerate ABA metabolism in the seed tissue leading to an early recovery from ABA-induced inhibition. 相似文献
98.
The fungitoxic effects of different plant extracts on Fusarium udum, which causes wilt disease of Cajanus cajan in vitro and in vivo, were examined. The complete arrest of the radial growth of the pathogen occurred at a 10% concentration of leaf extract from Adenocallyma alliaceum. A leaf extract of Citrus medica, a root extract of Asparagus adscendens, rhizome extracts of Curcuma longa and Zingiber officinale, and a bulb extract of Allium sativum inhibited up to 100% growth at higher concentrations. A. alliaceum controlled the disease up to 100% by amending its 4% powder in unsterilized soil and 2% in sterilized soil. The population of F. udum was found to be markedly reduced following treatments with plant powders. 相似文献
99.
d-Hydantoinase from the lentil, Lens esculenta, seed is quite unstable, and has been immobilized on Diethyl amino ethyl (DEAE) cellulose by an adsorption and cross-linking
method. The immboilized d-hydantoinase exhibited 80% enzyme activity and contained 86% protein. The immobilization of the enzyme preparation does not
change its optimum pH, temperature or affinity constant, but increases its shelf-life, thermostability and stability in various
organic solvents. This immobilized d-hydantoinase can be used effectively for the production of d-amino acids from the corresponding hydantoins and may therefore be of use in the chemical and pharmaceutical industries.
Received: 28 April 1998 / Received last revision: 10 July 1998 / Accepted: 10 July 1998 相似文献
100.
Measurements made in fresh water wetland have shown that temperature, pH, dissolved oxygen and bicarbonate alkalinity in the hyacinth infested area were lower, but dissolved free carbon dioxide concentration was excitingly greater than in the open water area. This extreme hypoxic and hypercarbic condition of hyacinth covered areas was caused by the thick coverage of Eichhornia crassipes which was crucial for the composition of the characteristic flora and fauna. 相似文献