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131.
Bone morphogenetic proteins (BMPs) initiate, promote, and maintain odontogenesis and osteogenesis. In this study, we studied the effect of bone morphogenic protein 2 (BMP 2) and bone morphogenic protein 7 (BMP 7) as differentiation inducers in tooth and bone regeneration. We compared the effect of BMP 2 and BMP 7 on odontogenic and osteogenic differentiation of human tooth germ stem cells (hTGSCs). Third molar-derived hTGSCs were characterized with mesenchymal stem cell surface markers by flow cytometry. BMP 2 and BMP 7 were transfected into hTGSCs and the cells were seeded onto six-well plates. One day after the transfection, hTGSCs were treated with odontogenic and osteogenic mediums for 14 days. For confirmation of odontogenic and osteogenic differentiation, mRNA levels of BMP2, BMP 7, collagen type 1 (COL1A), osteocalsin (OCN), and dentin sialophosphoprotein (DSPP) genes were measured by quantitative real-time PCR. In addition to this, immunocytochemistry was performed by odontogenic and osteogenic antibodies and mineralization obtained by von Kossa staining. Our results showed that the BMP 2 and BMP 7 both promoted odontogenic and osteogenic differentiation of hTGSCs. Data indicated that BMP 2 treatment and BMP 7 treatment induce odontogenic differentiation without affecting each other, whereas they induce osteogenic differentiation by triggering expression of each other. These findings provide a feasible tool for tooth and bone tissue engineering.  相似文献   
132.
Pure and boron (B) doped iron oxide (Fe2O3) nanostructured thin films were prepared by sol–gel spin coating method. The effects of B (0.1, 0.2, 0.5 and 1 %) content on the crystallinity and morphological properties of Fe2O3 films were investigated by X-ray diffractometer and atomic force microscopy. X-ray diffraction patterns revealed that the Fe2O3 films have a rhombohedral crystalline phase of α-Fe2O3 phase (hematite) with nanostructure and their crystallite size (D) is changed from 27 ± 2 to 45 ± 5 nm with B dopant content. The minimum crystallite size value of 27 ± 2 nm was obtained for 0.2 % B doped Fe2O3 film. Carrying out UV–VIS absorption study for both doped and undoped films at room temperature, it was realized that allowed optical transitions may be direct or indirect transitions. The direct and indirect energy gap values for pure Fe2O3 were obtained to be 2.07 and 1.95 eV, respectively. The optical band gap value of the films was changed with 0.1 % B doping to reach 1.86 eV for direct band gap and 1.66 eV in case of indirect band gap.  相似文献   
133.

Abstract  

A new 3,3′-dibenzoyl-1,1′-propan-1,3-diyl)bisthiourea was synthesized by using benzoylisothiocyanate with 1,3-diaminopropane in aprotic solvent. The structure was determinated by means of FT-IR, 1H-NMR, 13C-NMR and mass spectroscopic techniques. The crystal structure of 3,3′-dibenzoyl-1,1′-(propan-1,3-diyl)bisthiourea has also been examined by using X-ray crystallographic techniques and found to be crystallized in the monoclinic space group P2 1 /c with the unit cell parameters: a = 5.968(1) ?, b = 19.471(2) ?, c = 16.585(2) ?, β = 98.32(1)°, V = 1907.0(4) ?3, Dx = 1.395 g cm−3, and Z = 4 respectively.  相似文献   
134.
Supervisory controller design to enforce boundedness, reversibility, and liveness in timed-transition Petri nets with firing durations is considered. It is assumed that both controllable and uncontrollable transitions may be present and more than one transition may fire simultaneously. The approach of stretching is used to represent the state of the system. Algorithms are presented to design a supervisory controller using the forbidden states approach to enforce boundedness and reversibility simultaneously. The designed controller also guarantees T-liveness for the largest possible subset T of the set of transitions. In particular, boundedness, reversibility, and liveness are simultaneously enforced whenever it is possible. The designed controller is also the least restrictive controller which enforces boundedness and reversibility simultaneously.  相似文献   
135.

Abstract  

The title compound {6-[2-(2-chlorophenyl)-1,3-thiazol-4-yl]-2-oxo-1,3-benzothiazol-3(2H)-yl}acetic acid was prepared and characterized by elemental analyses, FT-IR, 1H NMR spectroscopy, X-ray diffraction. A quantum-chemical calculation was performed using the CNDO method. In the title compound, C18H11ClN2O3S2, the crystal structure is stabilized by intermolecular hydrogen bonds (C–H···O=C) to form centrosymmetric R22 R_{2}^{2} (16) dimers and the C–H···O, O–H···N, and C–H···N interactions generating the graph set motifs R22 R_{2}^{2} (9) and R22 R_{2}^{2} (22).  相似文献   
136.
An early on time detection of breast cancer significantly affects the treatment process and outcome. Herein, a new label-free impedimetric biosensor is developed to determine the lowest change in the level of calreticulin (CALR), which is a new biomarker of breast carcinoma. The proposed immunosensor is fabricated by using reduced graphene oxide/amino substituted polypyrrole polymer (rGO-PPyNH2) nanocomposite modified disposable electrode. The anti-CALR antibodies are first attached on the rGO-PPyNH2 nanocomposite coated electrode through glutaraldehyde crosslinking; the CALR antigens are then immobilized with the addition of CALR antigens to form an immunocomplex on the sensing surface. This immunocomplex induces considerably larger interfacial electron transport resistance (Rct). The variation in the Rct has a linear relationship with CALR level in the detection range of 0.025 to 75 pg mL−1, with a detection limit of 10.4 fg mL−1. The suggested biosensor shows high selectivity to CALR, good storage stability (at least 5 weeks) and suitable reproducibility results as shown in quality control chart. The designed immunosensor is utilized to analyze CALR levels in human sera with satisfying results. This immunosensor provides a novel way for the clinical determination of CALR and other cancer biological markers.  相似文献   
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