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81.
82.
Ali Riza Si?man Memduh Bülbül Canan Coker Banu Onvural 《Journal of trace elements in medicine and biology》2003,17(1):51-55
Cadmium is a nephrotoxic metal widely used in industry and the main source of Cd in general population is smoking. Considering that the source of Cd in cigarettes is the tobacco leaf, the exposure to Cd was evaluated in workers employed at a tobacco leaf processing factory. Blood and urinary Cd levels were measured by flameless atomic absorption spectrometry in 87 workers and 35 controls. Urinary enzymes, total protein, albumin and uric acid were also determined to investigate the possible nephrotoxic effects of Cd. Blood Cd levels were significantly higher in workers (1.63 +/- 1.95 microg/L) than in controls (0.91 +/- 1.15 microg/L) (p = 0.044). The increase observed in urinary Cd levels of workers was non significant (0.56 +/- 0.5 microg/g creatinine in workers and 0.46 +/- 0.5 microg/g creatinine in controls). Both in workers and in controls, subjects smoking >10 cigarettes/day showed significantly increased blood Cd levels compared to non-smokers (p = 0.000 and p = 0.011, respectively). In workers, urinary alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), total protein, and uric acid were observed to be significantly increased (p = 0.013, p = 0.000, p = 0.000, p = 0.025, respectively), ALP, GGT and total protein being positively correlated with Cd in urine. In conclusion, the workers in the tobacco leaf processing factory were found to be exposed to Cd compared to the general population. The increase in the urinary enzymes and proteins suggests that an exposure to Cd affects kidney functions even below the toxic limits generally accepted. 相似文献
83.
84.
Background
Images of frozen hydrated [vitrified] virus particles were taken close-to-focus in an electron microscope containing structural signals at high spatial frequencies. These images had very low contrast due to the high levels of noise present in the image. The low contrast made particle selection, classification and orientation determination very difficult. The final purpose of the classification is to improve the signal-to-noise ratio of the particle representing the class, which is usually the average. In this paper, the proposed method is based on wavelet filtering and multi-resolution processing for the classification and reconstruction of this very noisy data. A multivariate statistical analysis (MSA) is used for this classification.Results
The MSA classification method is noise dependant. A set of 2600 projections from a 3D map of a herpes simplex virus -to which noise was added- was classified by MSA. The classification shows the power of wavelet filtering in enhancing the quality of class averages (used in 3D reconstruction) compared to Fourier band pass filtering. A 3D reconstruction of a recombinant virus (VP5-VP19C) is presented as an application of multi-resolution processing for classification and reconstruction.Conclusion
The wavelet filtering and multi-resolution processing method proposed in this paper offers a new way for processing very noisy images obtained from electron cryo-microscopes. The multi-resolution and filtering improves the speed and accuracy of classification, which is vital for the 3D reconstruction of biological objects. The VP5-VP19C recombinant virus reconstruction presented here is an example, which demonstrates the power of this method. Without this processing, it is not possible to get the correct 3D map of this virus.85.
Mona El Khatib Przemyslaw Bozko Vindhya Palagani Nisar P. Malek Ludwig Wilkens Ruben R. Plentz 《PloS one》2013,8(10)
Cholangiocacinoma (CC) is a cancer disease with rising incidence. Notch signaling has been shown to be deregulated in many cancers. However, the role of this signaling pathway in the carcinogenesis of CC is still not fully explored. In this study, we investigated the effects of Notch inhibition by γ-secretase inhibitor IX (GSI IX) in cultured human CC cell lines and we established a transgenic mouse model with liver specific expression of the intracellular domain of Notch (Notch-ICD) and inactivation of tumor suppressor p53. GSI IX treatment effectively impaired cell proliferation, migration, invasion, epithelial to mesenchymal transition and growth of softagar colonies. In vivo overexpression of Notch-ICD together with an inactivation of p53 significantly increased tumor burden and showed CC characteristics. Conclusion: Our study highlights the importance of Notch signaling in the tumorigenesis of CC and demonstrates that additional inactivation of p53 in vivo. 相似文献
86.
We have studied the adsorption of atomic and molecular fluorines on a BC3 nanotube by using density functional calculations. It was found that the adsorption of atomic fluorine on a C atom of the tube surface is energetically more favorable than that on a B atom by about 0.97 eV. The adsorption of atomic fluorine on both C and B atoms significantly affects the electronic properties of the BC3 tube. The HOMO-LUMO energy gap is considerably reduced from 2.37 to 1.50 and 1.14 eV upon atomic F adsorption on B and C atoms, respectively. Molecular fluorine energetically tends to be dissociated on B atoms of the tube surface. The associative and dissociative adsorption energies of F2 were calculated to be about ?0.42 and ?4.79 eV, respectively. Electron emission density from BC3 nanotube surface will be increased upon both atomic and molecular fluorine adsorptions due to work function decrement. 相似文献
87.
Dai Yichen Cui Xiaolin Zhang Ge Mohsin Ali Xu Huiming Zhuang Yingping Guo Meijin 《Cytotechnology》2022,74(3):351-369
Cytotechnology - Human umbilical cord mesenchymal stem/stromal cells (hUC-MSCs) have attracted significant research interests in regenerative medicine and cell-based therapies due to their... 相似文献
88.
rafiei Ali Khodabakhsh Farnaz Cohan Reza Ahangari Azadegan-Dehkordi Fatemeh Salimian Morteza 《Molecular biology reports》2022,49(5):3389-3399
Molecular Biology Reports - Aberrant expression of long non-coding RNAs (lncRNAs) can contribute to the pathogenesis of coronary artery disease (CAD). In this study, we aimed to evaluate the... 相似文献
89.
Farrokhzad Yusuf Babaei Alireza Yadollahi Abbas Kashkooli Arman Beyraghdar Mokhtassi-Bidgoli Ali Hesami Shahriar 《Plant Cell, Tissue and Organ Culture》2022,149(3):535-548
Plant Cell, Tissue and Organ Culture (PCTOC) - We tested the feasibility to promote growth and shoot proliferation of Phalaenopsis through different wavelengths of LED and fluorescent. Therefore,... 相似文献
90.
Comparison of Th1 and Th2 responses in non-healing and healing patients with cutaneous leishmaniasis
Maryam Shahi Masoud Mohajery Seyyed Ali Akbar Shamsian Hossein Nahrevanian Seyyed Mohammad Javad Yazdanpanah 《Reports of Biochemistry & Molecular Biology》2013,1(2):43-48