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91.
Atay AA Kismet E Turkbay T Kocaoglu M Demirkaya E Sarici SU Congologlu A Gokcay E 《Biological trace element research》2005,105(1-3):197-203
The inhalation of a wide range of organic solvents has become popular among young adults. Toluene is one of the most commonly
used solvents in industry; it is easily available and conventient to use. Many toxicologic effects on biological systems secondary
to deliberate inhalation of toluene have been reported, but investigations on adverse effects associated with bone morbidity
is limited. The purpose of this study is to determine bone mineralization and investigate the adverse effects of toluene on
bone. The bone mineral density and content of the femoral neck of mice exposed to toluene at 300 ppm for 8 wk were measured
by dual X-ray absorptiometry and found significantly reduced compared to the control group. Chronic exposure to toluene was
found to affect bone metabolism, and toluene-induced changes could contribute to bone resorption and inhibition of bone formation.
Toluene seems to be the responsible component for the demineralizating effects of commonly abused substances, and medical
doctors must promote their education about the health hazards in those who abuse solvents especially in areas where inhalant
abuse is endemic. 相似文献
92.
Barli O Elmali D Midilli R Aydintan E Ustün S Sagsöz A Ozgen S Gedik T 《Collegium antropologicum》2005,29(1):45-51
This paper presents the results of an anthropometrical survey conducted on male and female children aged 3, 4 and 5 years in Turkey. A set of 18 body dimensions was taken from 154 males and 132 females. It is considered that the 18 parameters are necessary for the design of school furniture, fittings and equipment in order to minimize musculoskeletal, visual and circulatory problems resulting from badly designed elements. This study identified significant gender differences in a set of 18 anthropometrical measures in this subject group. 相似文献
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94.
Development and brain delivery of chitosan-PEG nanoparticles functionalized with the monoclonal antibody OX26 总被引:4,自引:0,他引:4
Aktaş Y Yemisci M Andrieux K Gürsoy RN Alonso MJ Fernandez-Megia E Novoa-Carballal R Quiñoá E Riguera R Sargon MF Celik HH Demir AS Hincal AA Dalkara T Capan Y Couvreur P 《Bioconjugate chemistry》2005,16(6):1503-1511
The inhibition of the caspase-3 enzyme is reported to increase neuronal cell survival following cerebral ischemia. The peptide Z-DEVD-FMK is a specific caspase inhibitor, which significantly reduces vulnerability to the neuronal cell death. However, this molecule is unable to cross the blood-brain barrier (BBB) and to diffuse into the brain tissue. Thus, the development of an effective delivery system is needed to provide sufficient drug concentration into the brain to prevent cell death. Using the avidin (SA)-biotin (BIO) technology, we describe here the design of chitosan (CS) nanospheres conjugated with poly(ethylene glycol) (PEG) bearing the OX26 monoclonal antibody whose affinity for the transferrin receptor (TfR) may trigger receptor-mediated transport across the BBB. These functionalized CS-PEG-BIO-SA/OX26 nanoparticles (NPs) were characterized for their particle size, zeta potential, drug loading capacity, and release properties. Fluorescently labeled CS-PEG-BIO-SA/OX26 nanoparticles were administered systemically to mice in order to evaluate their efficacy for brain translocation. The results showed that an important amount of nanoparticles were located in the brain, outside of the intravascular compartment. These findings, which were also confirmed by electron microscopic examination of the brain tissue indicate that this novel targeted nanoparticulate drug delivery system was able to translocate into the brain tissue after iv administration. Consequently, these novel nanoparticles are promising carriers for the transport of the anticaspase peptide Z-DEVD-FMK into the brain. 相似文献
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98.
Tinar S Sehirali S Inal MM Yildrim Y Celik E Yigit S 《MedGenMed : Medscape general medicine》2004,6(1):51
Adenosarcomas of the uterus are very rarely observed and diagnosed. In this report, we present a case of a uterine adenosarcoma that was diagnosed in February 2002. 相似文献
99.
After screening potential beta-lactamase producers in a medium containing penicillin G, an inducible (Bacillus subtilis NRS 1125) and a constitutive (Bacillus licheniformis 749/C ATCC 25972) beta-lactamase producer were selected. As the highest enzyme activity was obtained with B. licheniformis 749/C, the effects of the concentration of carbon sources, i.e., glucose, fructose, sucrose, citric acid, and glycerol, and nitrogen sources, i.e., (NH(4))(2)HPO(4), NH(4)Cl, yeast extract, casamino acids and peptone, pH, and temperature on beta-lactamase production were investigated with B. licheniformis 749/C in laboratory scale bioreactors. Among the investigated media, the highest volumetric activity was obtained as 270 U cm(-)(3) in the medium containing 10.0 kg m(-)(3) glucose, 1.18 kg m(-)(3) (NH(4))(2)HPO(4), 8.0 kg m(-)(3) yeast extract, and the salt solution at 32 degrees C and pH(0) = 6.0. By using the designed medium, fermentation and oxygen transfer characteristics of the bioprocess were investigated at V = 3.0 dm(3) bioreactor systems with a V(R) = 1.65 dm(3) working volume at Q(O)/V(R) = 0.5 vvm and N = 500 min(-1). At the beginning of the process the Damk?hler number was <1, indicating that the process was at biochemical reaction limited condition; at t = 2-5 h both mass-transfer and biochemical reaction resistances were effective; and at t = 6-10 h (Da >1) the bioprocess was at mass transfer limited condition. Overall oxygen transfer coefficients (K(L)a) varied between 0.01 and 0.03 s(-)(1), enhancement factor (K(L)a/K(L)a(O)) varied between 1.2 and 2.3, and volumetric oxygen uptake rate varied between 0.001 and 0.003 mol m(-)(3) s(-)(1) throughout the bioprocess. The specific oxygen uptake and the specific substrate consumption rates were the highest at t = 2 h and then decreased with the cultivation. The maximum yield of cells on substrate and the maximum yield of cells on oxygen values were obtained, respectively, as Y(X/S) = 0.34 and Y(X/O) = 1.40, at t = 5 h, whereas the highest yield of substrate on oxygen was obtained as Y(S/O) = 6.94 at t = 3.5 h. The rate of oxygen consumption for maintenance and the rate of substrate consumption for maintenance values were found, respectively, as m(O) = 0.13 kg kg(-)(1) h(-)(1) and m(S) = 3.02 kg kg(-)(1) h(-)(1). 相似文献
100.
Evren Terzi Cokun Kse Ümit Büyüksar Erkan Avc Nadir Ayrlm S. Nami Kartal 《International biodeterioration & biodegradation》2009,63(6):806-809
Particleboard specimens produced by adding waste tire rubber particles were assayed against white- and brown-rot fungi and termites in laboratory conditions. Particleboards were manufactured from a mixture of pine and poplar particles bonded with two different resins (melamine/urea formaldehyde [MUF] and polyisocyanate [PI]) by adding waste tire rubber particles at three different levels (10%/90%, 20%/80%, and 30%/70% by weight of waste tire rubber/wood). The particleboard specimens with waste tire rubber were not generally resistant against four fungi tested. Only MUF-containing specimens showed considerably better performance in decay resistance tests using the brown-rot fungus, Postia placenta; however, addition of waste tire rubber into those specimens did not provide resistance in comparison with control specimens without tire rubber. Formosan termites were also able to degrade particleboard specimens with waste tire rubber. 相似文献