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91.
Aldrin and dieldrin, structurally similar organochlorine pesticides belong to cyclodiene family and were widely used for agriculture and public health program in India. Although the manufacturing, use and import of aldrin and dieldrin have been banned in India since 2003, these pesticides are still persistent in environment and may be associated with adverse neurological and reproductive effects. The aim of this study is to assess the recent exposure level of aldrin and dieldrin and their placental transfer to fetus in normal healthy full-term pregnant women belonging to north Indian population undergoing normal delivery at Obstetrics and Gynecology department of UCMS and GTB hospital, Delhi. Quantitative analysis of aldrin and dieldrin residues in maternal and cord blood samples were carried out by gas chromatography system equipped with electron capture detector. The results of our study clearly revealed that maternal and cord blood levels of aldrin and dieldrin of pregnant women are age and dietary habit dependent. The aldrin level in maternal blood and dieldrin level in cord blood are higher in women in the age group 25–30 years than in women in age group of 19–24 years. Similarly, aldrin level in maternal blood is significantly higher in women with non-vegetarian dietary habit than in women with vegetarian dietary habit. No significant association is found for maternal and cord blood level. The results of the present study clearly demonstrate prenatal uptake of aldrin and dieldrin and provide recent information on the subsequent transplacental transfer.  相似文献   
92.
The cornerstone for an effective biomedical waste (BMW) management is appropriate waste segregation. Improper waste segregation practices can have an adverse impact on public health and increase the cost of treatment. Deficiencies in waste segregation practices can be corrected by continuous monitoring and education. Manpower for monitoring waste segregation in a large teaching hospital is scanty. We utilized the undergraduate medical students as monitors and studied the impact on waste segregation practices. A prospective observational study was carried out from August 2004 to January 2005. For monitoring waste segregation, the different areas of the hospital were divided amongst the II M.B.B.S students. They were provided with an observation sheet wherein the status of waste segregation and overall hygiene was recorded on a scale of 1-5. The impact of this programme was then analysed over the study period. The results indicated that a statistically significant improvement in waste segregation practices occurred in all areas. Thus, a large hospital with a medical college can identify students or a similar group for monitoring waste segregation or other aspects of biomedical waste management. This will improve their understanding of good practice in BMW management in future.  相似文献   
93.
Size fractionated chemical speciation of acidic aerosols were performed for ammonium sulfate, other sulfates, ammonium nitrate and other nitrates in a sub-tropical industrial area, Bina, India during December 2003 to November 2004. Analysis of variance (ANOVA) revealed highly significant temporal variations (p > .001) in the concentrations of nitrate and sulfate aerosols in all the three size fractions (fine, mid-size and coarse). Winter demonstrated utmost concentrations of ammonium sulfate, which ranged from 3.2 to 26.4 microg m(-3) in fine particles and 0.20-0.34 microg m(-3) in coarse particles. Ammonium sulfate was chiefly in fine mode (43.77% of total particulate sulfate) as compared to coarse particles (28.60% of total particulate sulfate). The major fraction Ammonium sulfate existed in different forms in atmospheric aerosols, for example NH4Fe(SO4)2, (NH4)2SO4, (NH4)3H(SO4)2 in fine particles, and (NH4)4(NO3)SO4+ in coarse particles. Other sulfate concentrations were also higher during winter ranging from 1.89 to 14.3 microg m(-3) in fine particles and 0.12-0.65microg m(-3) in coarse particles. Ammonium nitrate constituted the major fraction of total particulate nitrate all through the year and was principally in fine particles (the highest concentration in January i.e. 14.2 microg m(-3)). Other nitrates were mainly distributed in the fine particles (highest concentration in January i.e. 11.2 microg m(-3)) All the sulfate and nitrate species were mainly distributed in fine mode and have significant impact on human health.  相似文献   
94.
The present study deals with biology, ecology and population dynamics of freshwater turtle Kachuga tentoria and its role as water purifier. The study area Panchnada is the site, where five important national rivers meet together and is preserving an appreciable population of nine species of fresh water turtles. Kachuga tentoria was located at all the sampling stations surveyed by the authors, and hence selected for the present study. Different activities (nesting, incubation, predation and other reproductive aspects), climatic conditions, habitat, population density and morphometric features were worked out in detail. A time bound conservation strategy is needed to save this species from extinction. In situ conservation will be more helpful for the recruitment of the population of this species. It will help in the "hatch and release programme" to clean different polluted national rivers.  相似文献   
95.
Breast milk is the natural and optimal food for the infants. In addition to meeting the nutritional needs, breast milk provides numerous immunological, developmental, psychological, ecological and practical advantages. The levels of the DDT and HCH residues in human milk collected from remote rural part of Agra were analysed. Beta and gamma isomers of HCH accounts for the major residue of total HCH excreted in breast milk. Delta-HCH was not detected in the samples. 95% of the samples were found to be contaminated with DDT and its metabolites. DDD was found in 88% of the samples analyzed. The total concentration of DDT and HCH were found lower than the previous studies carried out in India. The study shows the decreasing levels of these organochlorine pesticides from the environment. Total concentration of total DDT is higher than total HCH.  相似文献   
96.
Studies were conducted on population dynamics of Metaphire posthuma, Lampito mauritii and Dichogaster bolaui in cultivated pedoecosystem of desert region of Rajasthan. The populations of aclitellate and clitellate M. posthuma, L. mauritii and D. bolaui were maximum in rainy season and minimum in summer season. The abundant population of these worms were found during the months of July to October. The species M. posthuma breed throughout the year except in extreme summer but L. mauritii breed twice in a year in the field. However, D. bolaui breed once in a year. Among these earthworm species D. bolaui with relative density of 44.2% was the most dominant species in cultivated land while L. mauritii and M. posthuma contributed 33.3% and 22.5% of density, respectively. The total population of earthworms showed significant positive correlation with different soil nutrients.  相似文献   
97.
98.
In the present study Tradescantia micronucleus (Trad-MCN) bioassay was performed to assess the genotoxicity of air pollutants in Varanasi City. The experiment was performed during October 2006 to April 2007. For Tradescantia micronucleus (Trad-MCN) bioassay four sites were selected, three in the city having different traffic characteristics and one control site virtually free from traffic intervention. Twenty young Tradescantia pallida inflorescences were collected from each sampling site during the study period and micronuclei frequencies were determined in early tetrads of pollen mother cells and expressed as MCN/100 tetrads. During the same period the concentration of different air pollutants were also measured. Tradescantia micronucleus (Trad-MCN) bioassay showed that the plants kept in areas having higher traffic emissions evidence higher micronuclei frequencies than samples kept at control site. The study indicates that in situ biomonitoring using higher plants may be useful for characterizing genotoxic air pollutants in areas even without any sophisticated instrument.  相似文献   
99.
The effects of sublethal concentration of fenvalerate on DNA, RNA, RNA/DNA ratio and protein contents were estimated in gill and kidney tissues of an air breathing fish, Clarias batrachus. Fenvalerate reduced the DNA content in gill, whereas it did not produce any significant effect on DNA in kidney. This tissue-specific change in DNA content may be due to differential effects of fenvalerate or its metabolite(s) on synthesis and/degradation of DNA in gill and kidney cells of the fish. RNA and protein contents declined substantially in both the tissues in response to fenvalerate treatment. However, RNA/DNA ratio remains unchanged. It indicates that decrease in protein content in response to fenvalerate treatment might have been brought about by reduce rate of translation of messenger (mRNA) without a decrease in concentration of ribosomes.  相似文献   
100.
The paper deals with 45 species of 21 genera of fresh water blue green algae (BGA) from three different agro-climatic zones of Uttar Pradesh. Samples were collected from different habitats varying in physico-chemical properties. Out of 45 species, 13 species belonged to order Chroococcales, 31 to order Nostocales, while only 1 species belonged to order Stigonimatales i.e. Fischerella mucicola. The physico-chemical parameters like pH, temperature, dissolved oxygen, electrical conductivity, nitrate, nitrite and rainfall play an important role in the periodicity of BGA. A positive correlation was found between dissolved oxygen (DO) of different ponds and species diversity, except in the case of western region of Uttar Pradesh (Farukhabad and Mahoba districts) where a positive correlation was found in electrical conductivity and total dissolved solids.  相似文献   
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