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771.
Fifty women residing in and around New Delhi, India and identified to have benign (25 nos.) and malignant (25 nos.) breast lesions were studied for the first time to access the association between environmental exposure to lead and risk of breast cancer and to determine the potential of changes in trace elements concentration as a diagnostic marker and/or its etiological involvement in the disease. Blood, tumor tissue and breast adipose tissue from tumor free area from each patient of the two groups, collected at the time of lumpectomy or mastectomy (only blood sample was collected from disease free control group), were analyzed to determine the concentration of Pb, Zn, Cu, Fe and Ca using Atomic Absorption Spectrometry. Blood lead was significantly higher in malignant cases than in those of benign and control (p<0.05 each). Lead level was also higher in tumor tissue when compared with their respective normal tumor free breast tissue, though non-significant, in both benign and malignant cases. Interestingly, Zn, Fe, and Ca levels were higher in blood of malignant cases than in those of their benign counterparts. Furthermore, these metals were also higher in tumor of malignant and benign cases as compared to normal tumor free breast tissue, many of them statistically significant (p<0.05/0.01/0.001). However, Cu level was insignificantly lower in the blood and tumor tissue of malignant cases when compared with their benign counterparts while it was significantly higher (p<0.05) in tumor of benign cases when compared with those of their respective normal tumor free breast tissue. There were statistically significant correlations between lead and trace element levels only in normal tumor free breast tissue of benign and malignant cases (r=0.41-0.73; p<0.05-0.001) but neither in blood nor tumor tissue of the two groups. These results suggest that in the backdrop of existing experimental and epidemiological evidences exposure to lead may be one of the risk factors for breast lesions; though it warrants further investigation. Further, modulation of trace elements level in both benign and malignant breast diseases patients may be of potential to be used as diagnostic marker of the disease process and its possible relationship etiologically.  相似文献   
772.
Journal of Material Cycles and Waste Management - Dwindling fossil fuels, and the rise in energy demand have urged us to explore alternative renewable energy forms. An integrated process of dark...  相似文献   
773.
Environmental Chemistry Letters - Fresh food products such as fruits and vegetables are usually degrading fast after harvest, notably due to the production of ethylene, an aging hormone, by the...  相似文献   
774.
This study focuses on environmental chromium contamination and pollution caused by the use of Chrome Composite Leather-Clad (CCLC) rollers commonly used in cotton roller ginning industries and attempts to eliminate this problem by providing eco-friendly chrome-less rollers.  相似文献   
775.
Two commercially available enzyme-linked immunosorbent assay (ELISA) kits that are commonly used for tylosin or tetracycline residues in meat and milk were adapted for ultratrace analysis of these antibiotics in surface and ground waters. These two antibiotics are commonly fed to swine, turkeys, and cattle at subtherapeutic doses for growth promotion purposes. Both ELISA techniques were found to be highly sensitive and selective for the respective antibiotics with detection limits of 0.10 and 0.05 microg L(-1) for tylosin and tetracycline, respectively. The recovery of both tylosin and tetracycline from spiked samples of lake waters, runoff samples, soil saturation extracts, and nanopure water was close to 100%. Tetracycline ELISA was highly specific for tetracycline and chlortetracycline but not for other forms of tetracycline (oxytetracycline, demeclocycline, and doxycycline). Analysis of a few liquid swine manure samples by liquid chromatography-mass spectrometry (LC-MS) showed lower concentrations for chlortetracycline as compared with concentrations obtained using ELISA. However, the concentrations of tylosin from ELISA were comparable with that of LC-MS. The lower concentrations of chlortetracycline obtained by LC-MS in manure samples indicate the presence of other similar or transformed compounds that were detected by ELISA but not determined by LC-MS. These results indicate that both ELISA kits can be useful tools for low-cost screening of tylosin, tetracycline, and chlortetracycline in environmental waters. Furthermore, both ELISA procedures are rapid, portable, and easily adaptable for testing of multiple samples simultaneously.  相似文献   
776.
Impact of distillery effluent (untreated and treated) irrigation on soil microflora of the pots used for growing Phaseolus aureus L. was investigated. The growth of the P. aureus plants as affected by distillery effluent irrigation was also evaluated. The irrigation of the pots by 1-10% distillery effluent (anaerobically treated) stimulated the growth of the soil microflora (increased number of bacteria, fungi and actinomycetes) and P. aureus plants (increased shoot and root lengths, biomass, chlorophyll and protein contents). Further, 15-20% distillery effluent (anaerobically treated) had toxic effect on soil micro flora as indicated by reduced number of bacteria, fungi and actinomycetes. Reduction in shoot, root, lengths, biomass, chlorophyll, protein contents of P. aureus was also observed when irrigated by 15-20% treated distillery effluent. All the concentrations of raw distillery effluent reduced the bacterial population. However, the treated distillery effluent concentrations <10% had stimulatory effect on fungal and actinomycetes population. However, raw effluent concentrations >5% reduced the same. Raw distillery effluent was more toxic to P. aureus than treated distillery effluent as concentrations >5%, had reduced the growth (shoot, root length and biomass) of the test plant. Raw distillery effluent had adverse effect to total chlorophyll contents and all the test concentrations reduced the total chlorophyll level. However, untreated (raw) distillery effluent stimulated the protein content initially. It has been concluded from-present study that lower concentrations of the raw distillery effluent (1-5%) and treated distillery effluent (1-10%) had stimulated the growth of P. aureus and soil microflora except soil bacteria (inhibited by all the concentration of the raw effluent). However, higher concentrations (raw effluent: 10-20%; treated effluent 15-20%) had toxicity to test parameters.  相似文献   
777.
The plants of Helianthus annuus L. var. modern were grown in the soil amended with different amounts of tannery sludge (10%, 25%, 35%, 50%, 75% and 100%), collected from Wastewater Treatment Plant Jajmau, Kanpur (Uttar Pradesh, India) under field conditions. The effect of tannery sludge amendments was studied on the growth performance of the plant, i.e. root length, shoot length, leaf area and number of leaves after 30, 60 and 90 days of exposures. The root length of the plant increased up to 35% tannery sludge followed by significant (p<0.01) decrease at higher amendments, whereas the shoot length of the plant increased with increase in sludge amendment ratio at all the exposure periods, compared to their respective controls. The number of leaves and leaf area in the plants of H. annuus increased at all the amendments of tannery sludge at initial exposure periods (30 and 60 days); however, it decreased at higher sludge amendments at highest exposure period (90 days) as compared to their respective controls. The analysis of scanning electron micrographs of the leaf surface of H. annuus grown on 50% and 100% tannery sludge after 90 days showed an increase in the frequency of stomata and trichomes, closure of stomata and degeneration of certain cells in the sludge grown plants.  相似文献   
778.
779.
Tannins (hydrolyzable and condensed) are water-soluble polyphenolic compounds that exert antinutritional effects on ruminants by forming complexes with dietary proteins. They limit nitrogen supply to animals, besides inhibiting the growth and activity of ruminal microflora. However, some gastrointestinal microbes are able to break tannin–protein complexes while preferentially degrading hydrolyzable tannins (HTs). Streptococcus gallolyticus, Lonepinella koalarum and Selenomonas ruminantium are the dominant bacterial species that have the ability to degrade HTs. These tanninolytic microorganisms possess tannin-degrading ability and have developed certain mechanisms to tolerate tannins in feeds. Hence, selection of efficient tanninolytic microbes and transinoculation among animals for long-term benefits become areas of intensive interest. Here, we review the effects of tannins on ruminants, the existence and significance of tannin-degrading microorganisms in diverse groups of animals and the mechanisms that tannin-degrading microorganisms have developed to counter the toxic effects of tannin.  相似文献   
780.
Singh SK  Yadav RP  Tiwari S  Singh A 《Chemosphere》2005,59(2):263-270
The aqueous stem bark and leaf extracts of plant Euphorbia hirta (family-Euphorbiaceae) have potent molluscicidal activity. Sub-lethal doses (40% and 80% of LC50) of aqueous stem bark and leaf extracts of this plant also significantly (P<0.05) alter the levels of total protein, total free amino acid, nucleic acids (DNA and RNA) and the activity of enzyme protease and acid and alkaline phosphatase in various tissues of the vector snail Lymnaea acuminata in time and dose dependent manner. Euphorbia hirta (family-Euphorbiaceae) commonly known as Dudhi, is a common medicinal plant of India, which is used in variety of diseases i.e. cough, asthma, colic, dysentery, genito urinary diseases.  相似文献   
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