Article | 2007 | International Journal of Applied Ceramic Technology4 ( 2 ) , pp.152 - 163
Calcite (CaCO3) is a geologically abundant material, which can be used as a starting material in producing biomedical scaffolds for clinical dental and orthopedic applications. Bone-filling applications require porous, biocompatible, and resorbable materials. Commercially available CaCO3 powders were physically mixed, for 80-90 s, with an orthophosphoric acid (H3PO4) solution, which was partially neutralized to pH 3.2 by adding NaOH, to form biphasic, micro-, and macroporous calcite-apatitic calcium phosphate (Ap-CaP) cement scaffolds of low strength. The resultant carbonated and Na-doped Ap-CaP phase in these scaffolds crystallogra . . .phically and spectroscopically resembled calcium hydroxyapatite. Upon mixing CaCO3 powders and the setting solution, carbon dioxide gas was in situ generated and formed the pores. Thus formed scaffolds contained pores over the range of 20-750 µm. Scaffolds were also converted to single-phase Ap-CaP, without altering their porosity, by soaking them in 0.5 M phosphate buffer solutions at 80°C for 36 h in glass bottles. Soerensen's buffer solution was also shown to be able to convert the calcite powders into single-phase Ap-CaP powders upon soaking at 60-80°C. This robust procedure of synthesizing Ap-CaP bioceramics is simple and economical. © 2007 Blackwell Publishing Ltd Daha fazlası Daha az
O. Yavas | M. Yazici | O. Eren | B. Oyan
Article | 2007 | Swiss Medical Weekly137 ( 39-40 ) , pp.556 - 558
Objectives: Although trastuzumab therapy is known to be associated with congestive heart failure, its arrhythmogenic potential has not been studied in detail. The purpose of this study was to determine the acute influence of trastuzumab infusion on electrocardiogram (ECG) parameters in patients with metastatic breast cancer. Patients and methods: Twenty patients with HER2 overexpressing metastatic breast cancer and normal cardiac function were enrolled in this single-centre prospective study. Standard 12-lead ECG recordings were performed at baseline and after trastuzumab infusion (2 mg/kg given over 30 min). P-wave durations, QT an . . .d RR intervals were measured and QT dispersion (QTd) and P-wave dispersion (Pd) were calculated. Results: In comparison with baseline, no statistically significant change in any ECG parameters, including QT and RR intervals, P wave durations, Pd and QTd, was observed after infusion of trastuzumab. Conclusion: In this study, no abnormality of atrial and ventricular depolarisation and repolarisation, indicated by Pd and QTd, was detected after infusion of trastuzumab. As Pd and QTd are both known to be associated with increased risk of serious arrhythmias and sudden death, it would appear that trastuzumab has no acute arrhythmogenic potential related to cardiac depolarisation and repolarisation Daha fazlası Daha az
G. Ünal | I. Iyigünler | C.M. Khalique
Article | 2007 | Journal of Nonlinear Mathematical Physics14 ( 3 ) , pp.430 - 442
Necessary and sufficient conditions for the linearization of one-dimensional nonautonomous jump-diffusion stochastic differential equations are given. Stochastic integrating factor is introduced to solve the linear jump-diffusion stochastic differential equations. Closed form solutions to certain linearizable jump-diffusion stochastic differential equations are obtained.
SS Keskin | N Aslan | F Bayrakceken
Article | 2007 | SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY67 ( 03.04.2020 ) , pp.1067 - 1071
X-ray, ultraviolet, and visible light induced photophysical changes of coumarin-540A in ethanol has been studied by the joint applications of X-ray, ultraviolet, and visible spectroscopy. Some impurities were found by X-ray fluorescence measurements. During the high power optical pumping, coumarin showed photochemical changes. Photoproduct emission spectra characteristics showed that photoproduct molecules could also be used as a laser-dye at a different emission frequency in the ultraviolet region. (c) 2006 Elsevier B.V. All rights reserved.
Z. Aktaş | Ş. Özdek | U. Asli Dinç | N. Akyürek | V. Atalay | G. Güz | B. Hasanreisoglu
Article | 2007 | Nephrology12 ( 4 ) , pp.380 - 385
Aim: Ocular surface changes and ocular symptoms may be encountered in patients with chronic renal failure (CRF) undergoing haemodialysis. The ocular surface changes and its relationship with metabolic control in CRF patients were aimed to be emphasized in this study. Methods: Thirty-eight CRF patients (75 eyes) undergoing haemodialysis were enrolled. Patients underwent a complete ocular examination together with Schirmer, tear break-up time tests, pachymetric measurements and conjunctival impression cytologies. Blood calcium, phosphate levels and total body volume changes after haemodialysis were recorded. Results: The most common f . . .indings were conjunctival calcification with red eye (81.3%) and dry eye (62.7%, according to tear break-up time test) in 75 eyes of 38 patients. Impression cytologies were graded as 0 in 57.3% of eyes and 2-3 in 40% of eyes showing positive correlation with the extent of conjunctival calcification (R = 0.486, P = 0.0001). Serum calcium and phosphate levels were also positively correlated with the degree of conjunctival calcification (R = 0.684, P = 0.0001 and R = 0.428, P = 0.0001, respectively) as well as with the grades of impression cytology (R = 0.587, P = 0.0001 and R = 0.385, P = 0.0001, respectively). Furthermore, the mean corneal thickness decreased significantly (9.31 ± 26.9 µm) following haemodialysis (Paired t-test, P = 0.002). Conclusion: Dry eye and irritational symptoms are major ocular symptoms in CRF patients. Serum calcium and phosphate levels seem to have a prognostic importance for the ocular findings and symptoms in patients with CRF. © 2007 The Authors Daha fazlası Daha az
H. Selim Karabekir | A. Yildizhan | E.K. Atar
Article | 2007 | Neurosciences12 ( 2 ) , pp.163 - 165
Lumbar discectomy is the most common operative technique at neurosurgery clinics around the world. The complications of lumbar disc operation include infections, dural tear, bleeding, vascular, and intestinal injuries. Infectious complications of lumbar disc surgery are superficial and profound tissue infections, meningitides, and epidural abscess. Although retained surgical sponges (gossypiboma) are well known intraoperative complications in other surgical branches, they have not been widely reported in neurosurgery. In this report, we present a case of retained surgical sponge at the operation site and discuss with the literature.
Usluata, A. | Bal, E.A.
Review | 2007 | Business Communication Quarterly70 ( 1 ) , pp.98 - 102
[No abstract available]
G Mercanoglu | H Uzun | F Mercanoglu | M Gungor
Conference Object | 2007 | EUROPEAN JOURNAL OF HEART FAILURE6 , pp.84 - 84
San, N. | Kiliç, M. | Tuiebakhova, Z. | Çinar, Z.
Conference Object | 2007 | Journal of Advanced Oxidation Technologies10 ( 1 ) , pp.43 - 50
The kinetics of the photocatalytic degradation of benzoic acid in the presence of TiO2 has been investigated experimentally and theoretically. The effects of catalyst loading, initial concentration of benzoic acid and the electron acceptors; H2O2, K 2S2O8 and OXONE on the degradation rate have been examined. A pseudo-first order kinetic model has been used to describe the results. With the intention of predicting the primary intermediates and the product distribution, geometry optimizations of the reactants, product radicals and transition state complexes have been performed with the semi-empirical PM3 and DFT/B3LYP/6-31G* methods. . . .Solvation effects have been computed by DFT calculations at the B3LYP/6-31G* level using COSMO as the solvation model. Based on the results of the quantum mechanical calculations, the rate constants of the four possible reaction paths have been calculated by means of Transition State Theory. A branching ratio for each of the reaction paths has been calculated and the product distribution for the degradation reaction has been determined. The results show that ortho-, meta- and para-hydroxybenzoic acids are formed as the primary intermediates in the photocatalytic degradation of benzoic acid. © 2007 Science & Technology Network, Inc Daha fazlası Daha az
Gu, X. | Zerbini, L.F. | Otu, H.H. | Bhasin, M. | Yang, Q. | Joseph, M.G. | Libermann, T.A.
Article | 2007 | Cancer Research67 ( 9 ) , pp.4219 - 4226
The epithelium-specific Ets transcription factor, PDEF, plays a role in prostate and breast cancer, although its precise function has not been established. In prostate cancer, PDEF is involved in regulating prostate-specific antigen expression via interaction with the androgen receptor and NKX3.1, and down-regulation of PDEF by antiproliferative agents has been associated with reduced PDEF expression. We now report that reduced expression of PDEF leads to a morphologic change, increased migration and invasiveness in prostate cancer cells, reminiscent of transforming growth factor ß (TGFß) function and epithelial-to-mesenchyntal tran . . .sition. Indeed, inhibition of PDEF expression triggers a transcriptional program of genes involved in the TGFß pathway, migration, invasion, adhesion, and epithelial dedifferentiation. Our results establish PDEF as a critical regulator of genes involved in cell motility, invasion, and adhesion of prostate cancer cells. ©2007 American Association for Cancer Research Daha fazlası Daha az
Otu, H.H. | Can, H. | Spentzos, D. | Nelson, R.G. | Hanson, R.L. | Looker, H.C. | Thadhani, R.
Article | 2007 | Diabetes Care30 ( 3 ) , pp.638 - 643
OBJECTIVE - We examined whether proteomic technologies identify novel urine proteins associated with subsequent development of diabetic nephropathy in subjects with type 2 diabetes before evidence of microalbuminuria. RESEACH DESIGN AND METHODS - In a nested case-control study of Pima Indians with type 2 diabetes, baseline (serum creatinine
Çomunoglu, N. | Çomunoglu, C. | Ekici, A.I.D. | Özkan, F. | Dervişoglu, S.
Article | 2007 | Polish Journal of Pathology58 ( 1 ) , pp.7 - 11
Spindle cell lipomas are a group of benign lipogenic soft tissue tumors. Typically they occur in posterior back and shoulder of elderly male patients. Differential diagnosis of this tumor became more important because the number of reports about some other tumors of similar morphology such as mammary type myofibroblastoma and solitary fibrous tumor, are increasing. All these tumors compose of bland spindle cells, mature adipocytes and collagen bundles. In this retrospective study we evaluated clinicopathological and immunohistochemical features of 18 cases of spindle cell lipomas. 15 cases of classical spindle cell lipomas and 3 ple . . .omorphic lipoma variant were all histologically characteristic. Immuohistochemically they were all CD34 positive. Ten cases, whose paraffin blocks available, were desmin negative. We think that spindle cell lipomas are desmin negative tumors and this feature helps us to differentiate them especially from mammary type myofibroblastomas of extramammarian soft tissue Daha fazlası Daha az