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981.
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984.
Ensuring the health of street-involved children is a growing public health challenge. These children are vulnerable, neglected, and rarely a priority for basic service providers and governments. Sizable populations of street-involved children are present in major urban areas worldwide and current trends in urbanization suggest these populations will grow in the coming years. Although migration offers employment and training opportunities, the health and wellbeing of children is negatively impacted by their interactions with the streets. However, systemic barriers may also prevent these children from achieving an adequate health status. The situation of street-involved children in Ghana, West Africa will be discussed.  相似文献   
985.
An in vitro lipolysis model was utilized to study the effect of stigmastanol (lipophilic phytosterol) and disodium ascorbyl phytostanol phosphate (DAPP) (modified hydrophilic phytostanol) on intestinal processing of cholesterol to gain further understanding of their cholesterol lowering mechanism. Lipolysis results showed that stigmastanol, if given in powder alone, had no effect on cholesterol processing probably due to its poor solubility. Stigmastanol suspension formulation re-distributed cholesterol from aqueous phase to oil and sediment phases. The water soluble DAPP has changed cholesterol distribution even more significantly by transferring cholesterol from aqueous phase to sediment phase. Moreover, the results provided evidence that DAPP inhibited triglyceride digestion in vitro. Considering DAPP as a surfactant with the same lipophilic sterol ring as bile salt, its ability to inhibit triglyceride lipolysis may be due to its competition with bile salt for the substrate surface, thereby hindering the lipolysis of triglyceride and inhibiting cholesterol solubilization with the lipolysis products. It can be speculated that the cholesterol lowering mechanism of DAPP during intestinal digestion is related to its ability to act as a surfactant closely resembling bile salt.  相似文献   
986.
987.
In the present study, 44 arsenic-resistant bacteria were isolated through serial dilutions on agar plate with concentrations ≥0.05 mM of sodium arsenite and ≥10 mM of sodium arsenate from Mandovi and Zuari—estuarine water systems. The ars genotype characterization in 36 bacterial isolates (resistant to 100 mM of sodium arsenate) revealed that only 17 isolates harboured the arsA (ATPase), B (arsenite permease) and C (arsenate reductase) genes on the plasmid DNA. The arsA, B and C genes were individually detected using PCR in 16, 9 and 13 bacterial isolates respectively. Molecular identification of the 17 isolates bearing the ars genotype was carried using 16S rDNA sequencing. A 1300 bp full length arsB gene encoding arsenite efflux pump and a 409 bp fragment of arsC gene coding for arsenate reductase were isolated from the genera Halomonas and Acinetobacter. Phylogenetic analysis of arsB and arsC genes indicated their close genetic relationship with plasmid borne ars genes of E. coli and arsenate reductase of plant origin. The putative arsenate reductase gene isolated from Acinetobacter species complemented arsenate resistance in E. coli WC3110 and JM109 validating its function. This study dealing with isolation of native arsenic-resistant bacteria and characterization of their ars genes might be useful to develop efficient arsenic detoxification strategies for arsenic contaminated aquifers.  相似文献   
988.
HPV-16 is reported as the cause of cervical and other related carcinomas. The early expressed protein E6 in cancer cells is found to be the target for immune therapeutic methods. The sequence of HPV-16 E6 (Accession No: ABK32509) from NCBI databank has been taken for this study. Hydrophilicity, flexibility, accessibility, turns, exposed surface, polarity and antigenic propensity scales were used for the B cell epitope prediction. MHC Class I and Class II alleles for the accession were predicted by the MHCPred 2.0 Program. The epitope sequences were also found out. Computer-based prediction program results show, A0203 and DRB0101 lower IC50 than other alleles. The best peptide binding affinity was 21HLCTELQTT30 of A0203 allele. In DRB0101 allele the peptide found was 39YCKQQLLRR48. Different structural features of the protein have also been predicted including glycosylation, kinase C phosphorylation, casein kinase II phosphorylation and N-myristylation sites. These computational prediction programs show four glycosylation, five kinase C phosphorylation, two casein kinase II phosphorylation, zero N-myristylation sites and seven disulphide sites. Development and approval of new vaccines are the keys for control of cancer. Epitopes and other structural features of protein prediction could be the best source of information and can help in molecular and medical studies of viral infection and development of HPV associated cancer drugs.  相似文献   
989.
In an attempt to find new agents to fight against microbial infections, a series of coumarin-based 1,3,4-oxadiazol-2ylthio-N-phenyl/benzothiazolyl acetamides was synthesized starting from coumarin-3-carboxylic acid ethyl ester obtained through Knoevenagel and Pinner reaction. In vitro antimicrobial activity against several bacteria (S. aureus, B. cereus, E. coli, P. aeruginosa, K. pneumoniae, S. typhi, P. vulgaris, S. flexneri), fungi (A. niger, A. fumigatus, A. clavatus, C. albicans) and antimycobacterial activity against Mycobacterium tuberculosis H37Rv strain was assessed. This study shows to what extent the presence of various electron withdrawing/donating substituents on the phenyl or benzothiazole ring affects the activity profiles of the newer molecules. The relationship between activity profiles (MICs, 3.12–25 μg/mL) and the lipophilic character (LogP) of the prepared products is also discussed and the MIC values of the active conjugates seem to correlate to some extent with the lipophilicity profiles. Two (5e and 6c) of the final analogues displayed promising antimycobacterial activity at 12.5 μg/mL of MIC, half fold potent to the standard drug pyrazinamide (6.25 μg/mL). Compounds were characterized by IR, 1H NMR, 13C NMR spectroscopy and elemental analysis.  相似文献   
990.
In the present communication, a series based on 1-[2-(6-nitro-4-oxo-2-phenyl-4H-quinazolin-3-yl)-ethyl]-3-phenyl-urea have been synthesized by an efficient synthetic protocol. The synthesized compounds were characterized by IR, 1H NMR, 13C NMR spectroscopy, ESI Mass spectrometry, and elemental analysis. The antibacterial and antifungal activity of the compounds were studied against selected strains (Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 11774, and Candida albicans ATCC 66027) by using Kirby Bauer disk diffusion technique and broth dilution technique. All the synthesized compounds showed good antifungal potency against strain C. albicans.  相似文献   
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