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991.
Plasmonics - Co-TiO2 nanoparticle thin films were synthesized by sol-gel method. The structural properties of the synthesized sample were studied using FTIR, XRD, and TEM. XRD confirmed the... 相似文献
992.
Halla Mohamed Ragab Nervana Samy Mie Afify Nabila Abd El Maksoud HebatAllah Mohamed Shaaban 《Journal of Genetic Engineering and Biotechnology》2018,16(2):479-484
Breast cancer is the most common cancer in females, it accounts for one third of all malignancies affecting women. Appropriate biomarkers play significant role in predicting the prognosis and decide the specific therapy to each patient. In this study we aimed at evaluating the value of Ki-67 as a prognostic marker in breast cancer patients and to analyze the associations between Ki-67 and their clinicopathological parameters. This study included 92 patients with developed non metastatic breast cancer and 10 women had benign breast tumor served as controls. We measured the serum level by ELISA technique and tissue expression of Ki-67 by immunohistochemical technique. Our results showed that there were no statistically significant differences in serum Ki-67 levels between the two studied groups. As for Ki-67expression in breast cancer cells, the score increases with increase of tumor size, grade, premenopausal, Ki-67 expression in estrogen and progesterone receptor positive tumors showed lower values than estrogen and progesterone negative tumors, while higher Ki-67 expression was more frequently associated with HER2-positive. In conclusion; our study supports the finding that tissue Ki-67 expression may add prognostic information to that obtained from classical prognostic factors and can provide data of significant value to other important prognostic indicators such as pathological grading, and axillary lymph node involvement. 相似文献
993.
Mandana Saki Mahboubeh Khaton Ghanbari Meysam Behzadifar Mohammad Hasan Imani-Nasab Masoud Behzadifar Samad Azari Ahad Bakhtiari Jianhong Wu Nicola Luigi Bragazzi 《The Yale journal of biology and medicine》2021,94(1):13
Background: In December 2019, a viral outbreak occurred in China, and rapidly spread out worldwide. Due to the lack of immediately available vaccines and effective drugs, many policy- and decision-makers have focused on non-pharmacological methods, including social distancing. This study was aimed at assessing the effects of the implementation of this policy in Iran, one of the countries most affected by COVID-19. We conducted a quasi-experimental study, utilizing the interrupted time series analysis (ITSA) approach. Methods: We collected daily data between February 20, 2020 and January 29, 2021, through governmental websites from 954 public hospitals and healthcare settings. The Iranian government launched the social distancing policy on March 27, 2020. Statistical analyses, including ITSA, were carried out with R software Version 3.6.1 (London, UK). Results: During the study period, 1,398,835 confirmed incidence cases and 57,734 deaths occurred. We found a decrease of -179.93 (95% CI: -380.11 to -20.25, P-value=0.078) confirmed incidence cases following the implementation of the social distancing policy, corresponding to a daily decrease in the trend of -31.17 (95% CI: -46.95 to -15.40, P-value=0.08). Moreover, we found a decrease of -28.28 (95% CI: -43.55 to -13.01, P-value=0.05) deaths, corresponding to a daily decrease in the trend of -4.52 (95% CI: -5.25 to -3.78, P-value=0.003). Conclusion: The growth rate of confirmed incidence cases and deaths from COVID-19 in Iran has decreased from March 27, 2020 to January 29, 2021, after the implementation of social distancing. By implementing this policy in all countries, the burden of COVID-19 may be mitigated. 相似文献
994.
Mohamadreza Baghaban Eslaminejad Samad Nadri 《In vitro cellular & developmental biology. Animal》2009,45(8):451-459
Marrow culture from mice has been reported to be overgrown by non-mesenchymal cells. In almost all protocols for isolation
of murine mesenchymal stem cells (MSCs), high density culture systems have been employed. Since MSCs are colonogenic cells,
the initiating cell seeding density may have significant impact on their cultures. This subject was explored in this study.
For this purpose, the bone marrow cells from NMRI mice were plated at 2.5 × 106 cells/cm2 and upon confluency were reseeded as either low density (50 cells/cm2) or high density (8 × 104 cells/cm2) cultures. The cells were expanded through an additional subculture and the passage 2 cells as a product of two culture systems
were statistically compared with respect to their surface antigen profiles and osteogenic culture mineralization. While low
density culture grew with multiple colony formation, there were no distinct colonies in high density cultures. In contrast
to high density cultures, passage 2 cells from low density system possessed typical homogenous fibroblastic morphology. Some
cells from high density system but not the low density cultures expressed hematopoietic and endothelial cell markers including
CD135, CD34, CD31, and Vcam surface antigens. Furthermore, osteogenic cultures from low density system displayed significantly
more mineralization than those from high density system. Taken together, it seems that low density culture system resulted
in more purified MSC culture than its counterpart as high density culture system. 相似文献
995.
Jahandideh S Barzegari Asadabadi E Abdolmaleki P Jahandideh M Hoseini S 《Journal of theoretical biology》2007,248(4):721-726
In order to investigate the structural distribution responsible for protein psychrophilicity, a systematic comparative analysis of 13 pairs of psychrophilic and mesophilic proteins is reported. Three kinds of residue structural states such as exposed, intermediate and buried were considered for analyzing the structural patterns of single amino acids and amino acids in different groups. The statistical test revealed that higher frequency in exposed state of Ala, higher frequency in intermediate state of His, lower frequency in buried state of Lys, lower frequency in exposed state of Gln, higher frequency in exposed state and in intermediate state of Thr, higher frequency in exposed and intermediate state of tiny and small amino acids groups could be critical factors related with protein psychrophilicity. Such structure-based differences of residual properties would help to develop a strategy for designing psychrophilic proteins. 相似文献
996.
Abd El-Rehim HA El-Sawy NM Hegazy el-SA Soliman el-SA Elbarbary AM 《International journal of biological macromolecules》2012,50(2):403-413
Modification of chitosan (CS) to N-maleoylchitosan (NMCS), N-phthaloylchitosan (NPhCS) and sulfonated-chitosan (SCS) was done using maleic anhydride, phthalic anhydride and chlorosulfonic acid, respectively followed by exposing them to γ-rays at different doses. The molecular weights and structural changes of irradiated chitosan derivatives were determined by GPC, FT-IR and UV-vis spectrophotometer. The molecular weights decreased with increasing irradiation dose. Results revealed that the main polysaccharide structure remained after irradiation. To investigate the enhancement of antioxidant activity of chitosan and its derivatives of different molecular weights, radical mediated lipid peroxidation inhibition, scavenging effect of DPPH radicals, reducing power and ferrous ion chelating activity assays were used. Chitosan derivatives with different molecular weights exhibit antioxidant activity. The lower the molecular weights of chitosan and its derivatives, the higher the antioxidant activity. NMCS possessed high scavenging effect on DPPH radicals compared with NPhCS, SCS and ascorbic acid. The irradiated chitosan and its derivatives could be used as natural antioxidants. 相似文献
997.
J. Silva-Navas C. Benito B. Téllez-Robledo D. Abd El-Moneim F. J. Gallego 《Molecular breeding : new strategies in plant improvement》2012,30(2):845-856
Soluble aluminum (Al3+) is a major constraint to plant growth in highly acidic soils, which comprise up to 50% of the world??s arable land. The primary mechanism of Al resistance described in plants is the chelation of Al3+ cations by release of organic acids into the rhizosphere. Candidate aluminum tolerance genes encoding organic acid transporter of the ALMT (aluminum-activated malate transporter) and MATE (multi-drug and toxic compound extrusion) families have been characterized in several plant species. In this study, we have isolated in five different cultivars the rye ScAACT1 gene, homolog to barley aluminum activated citrate transporter HvAACT1. This gene mapped to the 7RS chromosome arm, 25?cM away from the ScALMT1 aluminum tolerance gene. The gene consisted of 13 exons and 12 introns and encodes a predicted membrane protein that contains the MatE domain and at least seven putative transmembrane regions. Expression of the ScAACT1 gene is Al-induced, but there were differences in the levels of expression among the cultivars analyzed. A new quantitative trait locus for Al tolerance in rye that co-localizes with the ScAACT1 gene was detected in the 7RS chromosome arm. These results suggest that the ScAACT1 gene is a candidate gene for increased Al tolerance in rye. The phylogenetic relationships between different MATE proteins are discussed. 相似文献
998.
Entesar Ali Saber Mohammed Mustafa Abd El Aleem Neven Makram Aziz Randa Ahmed Ibrahim 《Journal of cellular physiology》2019,234(6):9168-9183
In case of a life-threatening, stressful event, the body prepares for an emergency. Indeed, the lung is unique in which alveolar cells are constantly exposed to physical and chemical stresses. This study aimed to study the impact of immobilization stress on the blood–air barrier and how it initiate and maintain an inflammatory response, plus determining the resolution of lung inflammation and repair. There was a significant increase in the plasma levels of stress markers “corticosterone and catecholamines” with a decrease in surfactant protein A (a lung-injury marker). Chronic stress produced a significant increase in the pulmonary oxidative and inflammatory markers malondialdehyde, tumor necrosis factor α, and induced nitric oxide synthase when compared with that of acute stress. Both stresses provoked marked pulmonary morphological and ultrastructural changes with a significant increase in caspase-3 immunoexpression. There was increasing evidence of lung’s capacity for repair. This process involved edema resolution, cell proliferation, and tissue remodeling in improving the lung-injury, oxidative, and inflammatory markers. 相似文献
999.
Nine children with severe pectus excavatum deformity were operated on in the Department of Pediatric Surgery, Thoracic Unit, Ege University Faculty of Medicine, Izmir, Turkey. There were four boys and five girls, and the mean age at operation was 6.3 years. A modified Ravitch technique was performed by using two polytetrafluoroethylene bars placed retrosternally for fixation and stabilization of the reconstituted anterior chest wall. The bars were removed 6 months after the operation. Results were satisfactory in all cases, with no surgical complications. 相似文献
1000.
Cycloaddition of the reactive intermediates 4 with 1-(cyanomethyl)benzotriazole (5) and its N-2 isomer 9 furnished, after spontaneous rearrangements, the 1,2,4-triazole derivatives 8 and 10. Analogously, reaction of 4 with ethyl cyanoacetate lead to the 1,3,5-trisubstituted 1,2,4-triazoles 12, which gave on treatment with hydrazine the corresponding hydrazides 13. Treatment of 13d with galactose or phenyl isothiocayanate gave the 1-D-galactose-acylhydrazone 14 and the 1,2,4-triazole derivative 15, respectively. Compounds 8c; 10b,c; 13a,c and 14 were selected for the antitumor screening, whereby 8c, 13a, and 13c showed remarkable activity against leukemia, ovarian, renal and lung cancers (8c with Gl(50) of 0.70 microM, 0.07 microM against leukemia (CCRF-CEM and RPMI-8226), 0.02 microM against ovarian (OVCAR-3) and 0.60 microM against renal (CARKI-1) and lung cancers, respectively). 相似文献