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101.
This study was designed to survey the incidence of Enterococcus faecalis infection in symptomatic and asymptomatic root canals of necrotic teeth using PCR and to isolate the bacterium for further screening. Sixty patients categorized according to their clinical symptoms were used for sampling by insertion of paper points into the root canals and absorbing all the fluids present within them. The samples were incubated in 1.0 ml 2xYT (containing 16 g bacto tryptone, 10 g yeast extract and 5.0 g NaCl per liter) for 24 h at 37 degrees C without aeration prior to multiplex PCR analysis. To assist the isolation of E. faecalis, sub-samples were further grown in the same medium supplemented with 6.5% NaCl and back-inoculated into bile esculin. Using multiple cultivation-dependent and PCR analyses, 6 cases (10%) of E. faecalis were identified. Four isolates were obtained from asymptomatic cases of chronic apical periodontitis, and the other two were associated with phoenix abscess and acute apical abscess, respectively. No E. faecalis infection was found in 5 patients with acute apical periodontitis or in 9 with chronic suppurative periodontitis. Our results indicate that there is no significant difference in the incidence of E. faecalis between symptomatic and asymptomatic necrotic dental root canals (P > 0.05).  相似文献   
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European Journal of Orthopaedic Surgery & Traumatology - Intramedullary nailing (IMN) is the treatment of choice in the surgical management of most tibia shaft fractures. The aim of the study...  相似文献   
103.
A series of 5,6-bisaryl-1,2,4-triazine-3-thiol derivatives were synthesized through microwave-promoted chemistry by condensation of the aromatic 1,2-diketones and thiosemicarbazide in a mixed green solvent. Subsequently, S-alkylation of 1,2,4-triazine-3-thiols afforded S-substituted derivatives. The anticonvulsant activity of the synthesized compounds was evaluated in vivo by electroshock and pentylenetetrazole (PTZ)-induced seizures tests. Among them, compound 4a bearing 4-pyridylmethylthio moiety on the triazine ring showed the highest protection in both electroshock and PTZ-induced seizures tests. Compound 4a showed no sign of neurotoxicity at the dose of 100 mg/kg in both rotarod and chimney tests.  相似文献   
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Sparfloxacin (SPFX) or 5-amino-1-cyclopropyl-7-[(3R,5S)3,5-dimethylpiperazine-1-yl]-6,8-difluoro-4-oxo-quinoline-3-carboxylic acid is an orally active synthetic, broad spectrum third generation quinolone, with excellent activity against Gram-positive bacteria with selectivity against anaerobes and atypical pathogens. Three derivatives of SPFX (2, 3, and 4) were synthesized by reacting different aromatic carboxylic acids with SPFX (1). Chemistry involved the formation of amide between reacting species through nucleophilic substitution reactions. The synthesized derivatives were then structurally characterized by IR, NMR, and mass spectroscopic techniques. The antimicrobial activities of these derivatives were evaluated against four Gram-positive, seven Gram-negative bacteria, and six fungi, using SPFX as a reference. Statistical analysis revealed these derivatives as active antimicrobial agents, and 2 was more potent antimicrobial agents than the parent drug as well other fluoroquinolones. Compounds 3 and 4 showed a significant activity against Fusarium solani. Moreover, these three derivatives were evaluated for inhibitory activities against enzyme urease, carbonic anhydrase II, and α-chymotrypsin. Results showed their selectivity against urease enzyme. Based on their nontoxic behavior, these derivatives may be potential agents for further studies.  相似文献   
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A new non-dispersive, anti-washout grout consisting of ordinary Portland cement, slag, superplasticizer, and methylbenzyl cellulose is proposed herein for the treatment of open karst, jointed and fractured rock, open-work gravel, and permeable sediments. A series of laboratory experiments were performed to design an anti-wash out grout suitable for grout injection of coarse aggregates depicting partially and open-jointed saturated rock mass and grouting concrete aggregates for underwater construction. The Taguchi orthogonal array was used to obtain nine different grout mix ratios. A total of four variables were considered, each with three different levels of the water–cement ratio, slag, and dosage of additives such as the superplasticizer and methyl benzyl cellulose. The laboratory determination of grout characteristics recording of mini slump, temperature, pH, visual assessment of grout dispersion, bleeding, and initial setting time and as well as uniaxial compressive strengths and permeabilities of the hardened grout samples were tested. To evaluate the suitability of the grout mixes, an analysis of variance was used for factor analysis and Grey relational analysis (GRA) was used to determine the optimal grout mix design. Based on the GRA, the following levels of the factors afforded the best results: water level 1 (0.3%), SP level 3 (0.01%), methylbenzyl cellulose level 2 (0.002%), and slag level 3 (0.1%). This paper describes the research methodology, detailed research observations, and analyses involved in designing the appropriate concrete mix. Based on the conclusions, relevant commendations regarding the suitability of grout testing equipment and grout mix designs are presented.  相似文献   
108.
In the present research, the degradation and decolorization of Reactive Black 5 synthetic dye at 30 ppm concentration under sun irradiation in the presence of a newly synthesized graphene based cobalt tin oxide nanocomposite were investigated. These nanoparticles were synthesized by a simple hydrothermal approach using precursor chloride salt i.e., stannous chloride and cobalt chloride and then adsorbed on the surface of RGO by a solvothermal process by changing the condition. The newly synthesized product was subjected to various instrumentation to study the morphology and other properties. X-ray powder diffraction analysis (XRD) explained the structural composition and various parameters of the product, which were further verified by Vesta software. The surface morphology of the product was analyzed by scanning electron microscopy (SEM) and it was observed that the size of each cube was approximately 5–10 μm from every face of the cube. Transmission electron microscopy (TEM) explained that the nanoparticles were within the range of 100–250 nm. These synthesized nanocubes were used in one more application, which was the investigation of the fuel efficiency in the presence of different concentrations of newly synthesized nanocomposites as a catalyst. The efficiency of kerosene oil was investigated by studying different parameters: the flash point, fire point, specific gravity, cloud point, pour point, and calorific value at increasing dosages of catalyst (0, 30, 60 and 90 ppm). It was observed that the values of these parameters changed significantly by changing the concentration of the catalyst dosage. The effect of the nanoparticles on the degradation of the RB 5 azo dye showed the highest removal percentage at the largest value of catalyst dosage, which was 0.70 mg ml−1 with the highest value of 3 ml of hydrogen peroxide.

Tin cobalt hydroxide nanoparticles were synthesized by a simple hydrothermal technique. A graphene based cobalt tin oxide nanocomposite was synthesized by a solvothermal method.  相似文献   
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BackgroundThe efficacy of antidiabetic agents for the treatment of non-alcoholic fatty liver disease (NAFLD) remains unclear.AimTo conduct a meta-analysis to study the efficacy of pioglitazone and three novel anti-diabetic agents: glucagon-like peptide-1 (GLP-1) agonists, sodium-glucose co-transporter-2 (SGLT2) inhibitors, and dipeptidyl-peptidase-4 (DPP4) inhibitors in treating NAFLD.MethodsOnline databases were searched in May 2020 for randomized clinical trials. Results from random-effects meta-analysis are presented as weighted mean differences (WMDs) or standard mean differences (SMDs) and corresponding 95% confidence intervals (CIs).ResultsTwenty-six studies (n=946 NAFLD patients) were included. Reductions in ALT were seen with all four drugs: pioglitazone (MD -38.41, p<0.001), SGLT2 inhibitors (MD -16.17, p<0.001), GLP-1 agonists (MD -27.98, p=0.04) and DPP-4 inhibitors (MD -7.41, p<0.001). Pioglitazone (SMD -1.01; p<0.001) and GLP-1 agonists (SMD -2.53, p=0.03) also demonstrated significant improvements in liver steatosis. SGLT2 inhibitors (SMD -4.64, p=0.06) and DPP-4 (SMD -2.49, p=0.06) inhibitors trended towards reduced steatosis; however, these results were non-significant.ConclusionPioglitazone demonstrates significant improvements in transaminases and liver histology in both diabetic and non-diabetic NAFLD patients. Early evidence from diabetic NAFLD patients suggests that novel antidiabetics may lead to improvements in liver enzymes and hepatic steatosis, and this should encourage further research into possible utility of these drugs in treating NAFLD.  相似文献   
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