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1.
In this study, we have reported selective synthesis of bismuth molybdate (γ-Bi2M2O6) nanoparticles (NPs) under different pH conditions for photocatalytic degradation of methylene blue (MB), reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) and antimicrobial activities. The synthesis of pure phase γ-Bi2M2O6 at pH = 3 was confirmed by X-ray diffraction (XRD) and Raman analysis. A single hexagonal morphology was obtained at pH = 3 which shows the formation of the pure phase γ-Bi2M2O6 NPs. The mixed morphologies (hexagonal and spherical) were observed at different pH values other than pH = 3. The bandgap energy of all the synthesized Bi2M2O6 NPs is found in the visible region (2.48–2.59 eV). The photocatalytic activity of bismuth molybdate (BM) NPs was examined by the degradation of MB under visible light irradiation. Results show that 95.44% degradation efficiency was achieved by pure γ-Bi2M2O6 NPs compared to mixed phases (γ-Bi2M2O6, α-Bi2M2O6 and β-Bi2M2O6) synthesized at pH = 1.5 and 5. Moreover, the degradation efficiency of γ-Bi2M2O6 was enhanced to 98.89% by the addition of H2O2. The effective catalytic activity of γ-Bi2M2O6 was observed during the reduction of 4-NP to 4-AP by NaBH4. Potential antibacterial and antifungal activity of γ-Bi2M2O6 was observed, which gives a basis for further study in the development of antibiotics.

In this study, we have reported selective synthesis of γ-Bi2M2O6 NPs under different pH conditions for photocatalytic degradation of methylene blue (MB), reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) and antimicrobial activities.  相似文献   
2.
In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal technique in the presence of l-cysteine. l-Cysteine can serve as a greener source of sulfur as well as a capping agent to help the growth of MoS2 nanosheets. The prepared materials were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), electron transmission microscopy (TEM), X-ray photoelectron microscopy (XPS), and Brunauer, Emmett, and Teller (BET) analysis. The results showed that MoS2 NSs are of high crystallinity with a lattice spacing of 0.61 nm. The optical bandgap of MoS2 NSs nanosheets prepared using l-cysteine as a source of sulfur was found to be 1.79 eV. The photocatalytic degradation of MoS2 NSs towards methylene orange (MO) and rhodamine blue (RB) dyes under sunlight was found to be promising for practical applications. The fast kinetics of degradation of MO and RhB was observed over a wide range of pH range. Moreover, MoS2 NSs showed excellent antifungal activities against Trichophyton mentagrophytes and Penicillium chrysogenum fungus.

In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal technique in the presence of l-cysteine.  相似文献   
3.
OBJECTIVES/HYPOTHESIS: To compare the sensitivity of an objective, computerized approach to measurement of facial synkinesis with that for a subjective approach and to examine the test-retest reliability of these approaches. STUDY DESIGN: Prospective, nonrandomized, and blinded. METHODS: Remote facial motion at the upper eyelids and oral commissures during a closed-lip smile and eyelid closure were measured using a commercially available computerized motion analysis system. Thirty healthy adults with normal facial nerve function were enrolled to establish normative data and a threshold value for synkinesis. Thirty consecutive patients were analyzed based on the synkinesis threshold value. Blinded subjective evaluations by two observers were also performed independently on the same patients. RESULTS: Facial synkinesis was detected significantly more frequently with objective than subjective analysis for eyelid closure; no significant differences between approaches were shown for the closed-lip smile. Interestingly, five (17%) patients developed early synkinesis within 3 months from the onset of the facial nerve injury. The test-retest reliability of all objective measures was excellent for both expressions. Close agreement in percent of patients with synkinesis between test and retest subjective evaluations was obtained for both observers for both expressions. CONCLUSIONS: The objective, computerized approach to detection of facial synkinesis has excellent reliability and is more sensitive than the subjective approach to assessment to the presence of facial synkinesis associated with eyelid closure. The finding of early synkinesis suggests that central nervous reorganization plays a role in regeneration of the facial nerve.  相似文献   
4.
A cross-sectional study was conducted among patients with tuberculosis on the DOTS regimen in the four teaching health centers of Jimma zone to determine rate of defaulting and factors associated with it. All tuberculosis patients registered and treated using DOTS regimen in the 4 teaching health centers (THC's) from the second half of 1999 to December 30, 2000 were included in the study. A sub-sample of one hundred and fourteen 114 (56.2%) defaulters were traced at their homes and interviewed to elicit their reasons for defaulting. The study showed that overall rate of defaulting was 6.7%. The default rate from the DOTS regimen was found to be quite low when compared to the rate of defaulting from the standard regimen in Jimma zone. Socio-economic factors including distance of patients' residence from the health institution, lack of money for paying transportation and poor awareness about the disease were the major reasons contributing to poor compliance and defaulting. Designing community based strategies for DOTS regimen in order to make the drug available within the vicinity of the grass root community and strong information education and communication activities need to be employed in order to reduce the defaulter rate and improve the quality of treatment of tuberculosis cases by the DOTS regimen.  相似文献   
5.
Belachew S  Gallo V 《Glia》2004,48(3):185-196
It is widely established that neurotransmitter receptors are expressed in non-neuronal cells, and particularly in neural progenitor cells in the postnatal central nervous system. The functional role of these receptors during development is unclear, but it needs to be revisited now that cells previously considered restricted to glial lineages have been shown to generate neurons. The present review integrates recent advances, to shed new light on how neurotransmitter receptors may, alternatively, serve as excitable mediators of neuron-glia and neuron-neuroblast interactions.  相似文献   
6.
Methyl substitution at the 2-position of the imidazole ring greatly improved drug metabolism profiles, in human liver microsomes, of ras farnesyl-protein transferase inhibitor (FTI) candidates for drug development. Methyl substitution markedly reduced the P450 inhibitory potency of non-substituted FTIs for CYP3A4 (by a factor of 12-403) and 2C9 (by a factor of 4.2-28), while it had little effect on the CYP2D6 enzyme. An immunochemical inhibition study demonstrated that CYP3A4 plays a predominant role in the metabolism of both non-substituted and 2-methyl-substituted imidazole-containing FTI candidates. Very strong type II binding spectra with human liver microsomes were observed for all non-substituted FTIs, while methyl substitution markedly weakened type II spectra or shifted the type of spectra from II to I. This indicated that methyl substitution on the imidazole moiety interfered with the substrate-P450 heme interaction, likely due to a steric effect caused by the methyl group. A kinetics study revealed that the methyl substitution increased V(max) and K(m) values to the same extent. These studies suggested that the 2-methyl substitution on the imidazole ring improved its drug metabolism profile by reducing the potential to inhibit CYP3A4-mediated metabolism without affecting intrinsic metabolic clearance (V(max)/K(m)).  相似文献   
7.
The diagnosis and management of anemia, which affects a significant proportion of young children in developing countries, largely depends on the clinical assessment for pallor. This study was conducted with the aim of evaluating the utility of pallor in detecting anemia. Children aged 2 to 60 months who visited the pediatric outpatient department of Jimma Hospital over 3 months period were assessed for the presence and degree of pallor in 4 anatomic sites (conjunctivae, tongue and buccal mucosa, nailbeds, palm) by trained nurses. Hemoglobin was then determined using the HemoCue method. Individuals involved in clinical examination did not have access to the laboratory results before documenting their findings. The mean hemoglobin in the 574 children examined was 11.03 gm/dl, and about 46% had anemia. Children younger than 2 years were found to have a higher prevalence of anemia as compared to older children (p < 0.001). Palmar pallor, with a sensitivity of 58%, had the highest sensitivity to detect moderate anemia as compared to other anatomic sites. The presence of either palmar or conjunctival pallor increased the sensitivity to 73%. The inter-observer agreement was highest for conjunctival pallor (kappa value = 0.81). The findings of the study suggest that pallor of a single anatomic site does not have adequate sensitivity to detect moderate anemia. We recommend further studies to look at the performance of severe pallor in correctly identifying severe anemia. Furthermore, the magnitude and causes of anemia need to be studied in a community setting.  相似文献   
8.
1. The in vitro metabolism of indinavir (CRIXIVAN, MK-0639, L-735,524), an HIV protease inhibitor, was evaluated using liver microsomes from cynomolgus monkey, rhesus monkey, chimpanzee and human. Indinavir exhibited marked species differences in metabolism. The overall rate of indinavir metabolism varied > 4-fold among primates (84 pmol/min/mg protein in cynomolgus monkey versus 20.4 pmol/min/mg protein in human) and followed the rank order: cynomolgus monkey > rhesus monkey > chimpanzee > human. 2. The cis-(indan)hydroxylated metabolite of indinavir was formed only in cynomolgus and rhesus monkey livers, whereas trans-(indan)hydroxylation and N-dealkylation were observed as the major metabolites in all primates tested. Inhibition studies with P450-selective inhibitors (ketoconazole, quinine, quinidine) and monoclonal antibodies (against CYP2D6 or CYP3A4) indicated that a cytochrome P450 isoform of the CYP2D subfamily is involved in the formation of the unique cis-(indan) hydroxylated metabolite in monkey, whereas all other oxidative metabolites, including the trans-(indan)hydroxylated metabolite, are formed by CYP3A isoform(s). 3. The present study has demonstrated that monkeys were unique in their abilities to form the stereoselective metabolite and were not appropriate surrogates for the qualitative prediction of indinavir metabolism in human.  相似文献   
9.

Background  

Good adherence to antiretroviral therapy is necessary to achieve the best virological response, lower the risk that drug resistance will develop, and reduce morbidity and mortality. Little is known about the rate and predictors of adherence in Ethiopia. Therefore this study determines the magnitude and predictors of adherence to antiretroviral therapy among people living with HIV/AIDS in Southwest Ethiopia.  相似文献   
10.
Two different cellular assay models were assessed as in vitro systems for P-glycoprotein (P-gp) substrate identification: cellular accumulation studies with KB-V1, a human MDR1 P-gp-overexpressing multidrug-resistant human epidermoid carcinoma cell line; and transcellular transport studies with L-MDR1 (or L-mdr1a), a human MDR1 (or mouse mdr1a)-transfected porcine renal epithelial cell line. The in vitro-in vivo correlation for P-gp-mediated transport activity was also examined by comparing in vitro data obtained from L-mdr1a cell studies and in vivo data from mdr1a (-/-)/(+/+) CF-1 mice studies for several compounds. The results are summarized as follows: 1) two in vitro assay systems routinely identified the substrate for human MDR1 P-gp-mediated transport with similar quantitative results; 2) in vitro studies with L-MDR1 and L-mdr1a cells demonstrated that the P-gp substrate susceptibility is different between human and mouse for certain compounds (species difference); and 3) in vivo brain concentration ratios of mdr1a (-/-) to (+/+) CF-1 mice, either at a certain time point or up to 60 min, correlated well with the in vitro transcellular transport ratios from L-mdr1a cells (r(2) = 0.968 and 0.926, respectively). This indicates that, at least in mice, the in vitro data are valid predictors of the in vivo contribution of P-gp: the contribution of P-gp to the distribution of the compound to the brain up to 60 min post i.v. administration. These results provide a rationale for predicting in vivo relevance of P-gp in human from in vitro data using human P-gp-expressing cells.  相似文献   
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