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In this paper, we for the first time show the ability of the mesophilic fungus Fusarium oxysporum in the bioleaching of waste material such as Fly-ash for the extracellular production of highly crystalline and highly stable, protein capped, fluorescent and water soluble silica nanoparticles at ambient conditions. When the fungus Fusarium oxysporum is exposed to Fly-ash, it is capable of selectively leaching out silica nanoparticles of quasi-spherical morphology within 24 h of reaction. These silica nanoparticles have been completely characterized by UV-vis spectroscopy, Photoluminescence (PL), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Energy dispersive analysis of X-rays (EDAX).  相似文献   
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Various national surveys suggest that the % of eligible couples in Bangladesh who are using traditional methods of contraception has been growing. This article presents detailed information on knowledge and use patterns of traditional methods and compares the use patterns of traditional and modern methods of contraception. The data are derived from the 1981 Contraceptive Prevalence Survey and information collected from a nationally representative sample of ever married women aged under 50, by way of field interviews using female interviewers. Quality of data was checked at different phases of the survey. Over 96% of the women reported that they knew at least 1 traditional method of contraception. The safe period was the most well known method (36.5%); about 30% reported knowledge of abstinence and 22% knew about withdrawal. Compared with modern methods, where knowledge declined with increased age, the knowledge of traditional methods shows no systematic pattern by age. Respondents with primary and higher education have higher knowledge of traditional methods than women who have never been to school. A similar pattern exists for employment status; non-Muslim women have consistently higher levels of knowledge than Muslim women. Data on patterns of use suggest that about 36% have used at least 1 contraceptive method, 15% having used traditional methods and 20.4% modern methods. The number of women who have used traditional methods increases from ages 20 to 44 and then declines. Use of traditional methods is relatively higher by the number of living children than by the number of children ever born. A similar pattern of association between background characteristics (education, employment and religion) and contraceptive knowledge is evident regarding level of use. Husband's level of education does not show any significant relationship with the use of traditional methods. The use rate of traditional methods was more than doubled among the women owning land compared to those having no land. The total current use rate of modern methods was higher among women aged 40-44 having relatively higher numbers of living children. As with current use, a positive relationship was observed between the socioeconomic variables and ever use. In general, it is concluded that socioeconomic variables played a dominant role in the decision of couples in choosing various methods of contraception. It is suggested that traditional methods still have an important role in family planning and that this should not be disregarded.  相似文献   
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Naim Uddin  Roma Chakraverty 《Grana》2013,52(5):345-349
Aeromycoflora studies above an “Aman” variety of paddy (Oryza saliva L.) were carried out for two consecutive seasons, in 1990 and 1991, in the vicinity of Barrackpore, West Bengal, by means of the culture plate exposure technique. A more or less uniform spore concentration was observed during the early part of the vegetative stages in 1990 with an abrupt increase and peak during the maximum vegetative growth period. In 1991, a uniform spore count was found up until the flowering stages. A gradual increase in spore count after flowering was recorded in both seasons with the highest peaks during harvesting, followed by a sudden decrease after the harvest. The dominant genera isolated were Aspergillus, Currularia, Cladosporium and Penicillium. Aspergillus appeared in high concentrations from the very beginning of the crop season up to the flowering stages, with a gradual fall after flowering, while Cladosporium showed the reverse pattern. Currularia and Penicillium occurred regularly throughout the crop season.

Phytopathogenic types were represented by Helminthosporium oryzae, Fusarium, Altemaria and Nigrospora. Helminthosporium oryzae appeared in the air when the plants attained appreciable vegetative growth, being seen as “brown spots” on the foliage, and reaching peak concentration during harvesting. Fusarium in contrast to Altemaria appeared regularly in the air except during the later part of vegetative growth. Nigrospora was recorded only occasionally. A considerable number of “Sterile Forms” were present throughout both seasons.  相似文献   
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Background:Myocardial infarction is one of the leading causes of morbidity and mortality worldwide. Oxidative stress plays a vital role in the pathogenesis of atherosclerosis leading to myocardial infarction and Glutathione S-transferases (GSTs) act as detoxifying enzymes to reduce oxidative stress. The aim of the present study was to investigate the associations of the GST (T1 & M1) gene polymorphism with the susceptibility of myocardial infarction in the Bangladeshi population.Methods:A case-control study on 100 cardiac patients with MI and 150 control subjects was conducted. The genotyping of GST (T1 & M1) gene was done using conventional Polymerase Chain Reaction.Results:The percentage of GSTM1 genotypes was significantly (p< 0.01) lower in patients compared to control subjects while the GSTT1 genotypes were not significantly different between the study subjects. The individual with GSTM1 null allele was at 2.5-fold increased risk {odds ratio (OR)= 2.5; 95 % confidence interval (95 % CI)= 1.4 to 4.3; p< 0.01} of experiencing MI while individual with either GSTM1 or GSTT1 genotypes was at lower risk. In the case of GST M1 and GST T1 combined genotype, patients having both null genotypes for GST M1 and GST T1 gene showed significantly (p< 0.01) higher risk of experiencing MI when compared to control subjects (OR= 3.5; 95% CI= 1.7–7.2; p< 0.001). Conclusion:Thus our recent study suggested that GSTM1 alone and GSTM1 and T1 in combination augments the risk of MI in Bangladeshi population. Key Words: Bangladesh, GST (T1 & M1), Myocardial infarction, PCR, Polymorphism  相似文献   
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Adenia trilobata, locally known as akandaphal in Bangladesh, has some traditional uses. Leaves and stems extracted with pure methanol (MEATL, MEATS) and fractioned by n-hexane (NFATL, NFATS), which was subjected to qualitative phytochemical analysis. The qualitative phytochemical analysis of four extracts showed the presence of secondary metabolites such as alkaloid, carbohydrate, glycosides, flavonoids, phenols, flavonol, and saponins. All four extracts of A. trilobata, exhibited a strong antioxidant activity while a moderately (MEATS = 328 μg/mL) to weakly toxic (NFATL = 616.85 μg/mL) LC50 observed in brine shrimp lethality bioassay. In thrombolytic test, MEATL (18.54 ± 2.18%; P < 0.01) and MEATS (25.58 ± 4.76%; P < 0.0001) showed significant percentage of clot lysis in human blood. The in vivo analgesic activity carried by acetic acid test and formalin test, while the antidiarrheal activity assayed by two standard methods e.g., castor oil-induced diarrhea and castor oil-induced gastrointestinal motility. Both, in vivo model, showed an extremely significant (P < 0.0001) dose-dependent manner percentage of inhibition in comparison to the control group. Present results suggested, A. trilobata could be a potential source for antioxidative, cytotoxic, thrombolytic, analgesic, antidiarrheal agents which require further study to identify the mechanism of A. trilobata.  相似文献   
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