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11.
Application and bioactive properties of CaTI,a trypsin inhibitor from Capsicum annuum seeds: membrane permeabilization,oxidative stress and intracellular target in phytopathogenic fungi cells 下载免费PDF全文
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Abdul Hai Alami Kamilia Aokal Di Zhang Aya Taieb Mohammed Faraj Alya Alhammadi Juveiriah Mohammed Ashraf Bassel Soudan Jinan El Hajjar Mihai Irimia‐Vladu 《国际能源研究杂志》2019,43(11):5824-5833
This paper presents a facile and economic development of dye‐sensitized solar cells using a nonprecious counter electrode made from ball‐milled tellurium‐doped graphene (Te‐Gr) and a natural sensitizer extracted from Calotropis gigantea leaves. The prepared materials were characterized using various techniques, such as Raman spectroscopy, X‐ray diffraction (XRD), atomic force microscopy (AFM), impedance spectroscopy, and scanning electron microscopy with built‐in energy‐dispersive X‐ray spectroscopy (SEM with EDS). The electrochemical activity of the produced counter electrodes and the impedance of the fabricated cells were examined and discussed to devise plans for future enhancement of cell performance. A clear pattern of improvement was found when using cost‐effective Te‐Gr relative to the costly platinum counter electrodes, especially when compared with cells employing another natural sensitizer. The results show approximately 51% enhancement over chlorophyll‐based cells made from spinach, where the added advantage in our approach is the utilization of an abundant plant extract with little nutritional appeal. 相似文献
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Poly-Si thin-film transistors (TFTs) with channel dimensions (width W , and length L ) comparable to or smaller than the grain size of the poly-Si film were fabricated and characterized. The grain size of the poly-Si film was enhanced by Si ion implantation followed by a low-temperature anneal and was typically 1 to 3 μm in diameter. A remarkable improvement was observed in the device characteristics as the channel dimensions decreased to W =L =2 μm. On the other hand, TFTs with submicrometer channel dimensions were characterized by an extremely abrupt switching in their I D versus V GS characteristics. The improvement was attributed to a reduction in the effect of the grain boundaries and to the effect of the device's floating body 相似文献
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CA Uyl-de Groot B L?wenberg E Vellenga S Suciu R Willemze FF Rutten 《Canadian Metallurgical Quarterly》1998,100(4):629-636
The acute hemodynamic effects of the phosphodiesterase (PDE) III inhibitor saterinone were compared with dobutamine and sodium nitroprusside in 12 patients with idiopathic congestive cardiomyopathy (NYHA III). Hemodynamic measurements were obtained with a Swan-Ganz thermodilution catheter. At the peak of its dose-response curve, saterinone induced an increase in cardiac index (+102%), stroke volume (+97%), and heart rate (+6%), paralleled by a decrease in pulmonary capillary wedge pressure (-46%), right atrial pressure (-51%), pulmonary arterial pressure (systolic -32%, diastolic -45%, mean -38%), systemic blood pressure (systolic -3%, diastolic -13%, mean -9%), systemic vascular resistance (-54%), and pulmonary vascular resistance (-58%). Dobutamine had similar effects on cardiac index (+106%) and stroke volume (+87%) but lacked vasodilatory characteristics. In contrast to dobutamine, both nitroprusside and saterinone demonstrated more pronounced vasodilatory effects. Nitroprusside was less effective on cardiac index (+66%) and stroke volume (+56%) than was saterinone. The double product was markedly increased by dobutamine (+28%), did not change with saterinone treatment (+2%), and decreased with nitroprusside (-10%). This indicates that according to double product, only the application of dobutamine caused a relevant increase in myocardial oxygen consumption. Saterinone was demonstrated to be a safe and potent drug on short-term application; it combines the vasodilating properties of sodium nitroprusside with the positive inotropic effects of dobutamine without major changes in myocardial oxygen consumption. 相似文献
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GJ Silverman JV Nayak K Warnatz FF Hajjar S Cary H Tighe VE Curtiss 《Canadian Metallurgical Quarterly》1998,161(10):5720-5732
In vitro studies of several naturally occurring proteins have characterized VH family-specific B lymphocyte binding and stimulatory properties that appear analogous to those of T cell superantigens. To examine the in vivo consequences of exposure to a putative B cell superantigen, we treated neonatal BALB/c mice with a form of staphylococcal protein A (MS) devoid of Fcgamma binding activity, which retains the clan VHIII Fab binding specificity. In naive adults, about 5% of peripheral B cells and >13% of splenic IgM-secreting cells display MS binding activity, in association with high IgM and low IgG circulating anti-MS Ab titers. Neonatal exposure to MS elicited two distinct temporal phases of immune responsiveness. The early phase, representing the first approximately 5 wk of life, was associated with MS-specific B cell and T cell tolerance. Microfluorometric assays revealed that exposure caused a dramatic MS-specific B cell clonal loss in bone marrow and spleen, but levels normalized by about 3 wk of life. The late phase (>6 wk of age) was associated with spontaneous priming for MS-specific T cell responses and production of MS-specific IgG1 Abs despite long term persistently depressed in vivo and in vitro MS-specific IgM responses. In vivo challenge during the late phase induced high frequencies of MS-specific IgG-secreting cells, indicating recruitment of highly focused Ab responses that were predominantly encoded by rearrangements of the S107 family, a member of the VHIII clan. These studies document the immunodominance of the VH-restricted Fab binding site on staphylococcal protein A and demonstrate the diverse effects of a B cell superantigen on the emerging peripheral B cell compartment. 相似文献
17.
K Garde AC Mortensen PB Toft MB S?rensen FF Madsen O Henriksen 《Canadian Metallurgical Quarterly》1994,35(2):197-200
The yeast gene, YTA10, encodes a member of a novel family of putative ATPases. Yta10p, as deduced from the nucleotide sequence, is 761 amino acids in length (predicted molecular mass 84.5 kDa). The amino acid sequence of Yta10p exhibits high similarity to two other yeast proteins, Yta11 and Yta12, and to E. coli FtsH. Several features of Yta10p are compatible with its localization in mitochondria. We report here that Yta10p is a yeast mitochondrial protein and that import is dependent on a membrane potential and accompanied by processing to a protein of approximately 73 kDa. Disruption of YTA10 leads to a nuclear petite phenotype and to a loss of respiratory competence, as shown by spectrophotometric measurement of the activities of respiratory complexes I-III and IV, respectively. These findings together with the high similarity of Yta10p to several ATP-dependent proteases suggest that Yta10p is a mitochondrial component involved, directly or indirectly, in the correct assembly and/or maintenance of active respiratory complexes. 相似文献
18.
MB Melo FF Costa ST Saad I Lorand-Metze S Bordin NN Ahmad 《Canadian Metallurgical Quarterly》1998,22(9):787-792
Patient 1: A 48-year-old man was admitted to Osaka Red Cross Hospital because of fever and dyspnea. Laboratory examination revealed pancytopenia, liver dysfunction and hematostatic abnormality. Chest radiographs obtained on admission revealed ground-glass opacity in both lung fields, and an analysis of arterial blood showed severe hypoxemia (PaO2:46.8 Torr). Pulse therapy with methylprednisolone was started. Although the hypoxemia subsided and radiographic findings rapidly improved, pancytopenia persisted. Examination of bone marrow aspirate revealed mature histiocytes with marked hemophagocytosis. Amplified Mycobacterium tuberculosis direct tests of bronchoalveolar lavage fluid, sputum, urine, and bone marrow were all positive, and Mycobacterium tuberculosis was cultured from sputum and urine. Although the patient was taking antituberculous agents, his pancytopenia persosted. Treatment with etoposide induced remssion. Patient 2: A 19-year-old woman was admitted to Osaka Red Cross Hospital because of prolonged cough and fever. Laboratory examination revealed leukocytosis, liver dysfunction, and hematostatic abnormality. Serologic tests provided conclusive evidence of Mycoplasma infection and a CRP test was strongly positive. Chest radiographs obtained on admission revealed infiltration shadows in the middle and lower lung fields on both sides, with left pleural effusion. An analysis of arterial blood showed hypoxemia (PaO2: 54.2 Torr). Examination of bone marrow and pleural effusion samples revealed mature histiocytes with marked hemophagocytosis. Although treatment with antibiotics and pulse therapy with methylprednisolone was started, the patients respiratory functions deteriorated. Endotracheal intubation was performed. Therapy with etoposide induced remission. Hemophagocytic syndrome associated with Mycoplasma infection and tuberculosis appears to be exceedingly rare. In these 2 cases, it was difficult to achieve remission with therapy for the underlying infections, but etoposide treatment was effective. 相似文献
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N Rothman G Talaska RB Hayes VK Bhatnagar DA Bell VM Lakshmi SK Kashyap M Dosemeci R Kashyap FF Hsu M Jaeger A Hirvonen DJ Parikh BB Davis TV Zenser 《Canadian Metallurgical Quarterly》1997,6(12):1039-1042
We evaluated the influence of urine pH on the proportion of urinary benzidine (BZ) and N-acetylbenzidine present in the free, unconjugated state and on exfoliated urothelial cell DNA adduct levels in 32 workers exposed to BZ in India. Postworkshift urine pH was inversely correlated with the proportions of BZ (r = -0.78; P < 0.0001) and N-acetylbenzidine (r = -0.67; P < 0.0001) present as free compounds. Furthermore, the average of each subject's pre- and postworkshift urine pH was negatively associated with the predominant urothelial DNA adduct (P = 0.0037, adjusted for urinary BZ and metabolites), which has been shown to cochromatograph with a N-(3'-phosphodeoxyguanosin-8-yl)-N'-acetylbenzidine adduct standard. Controlling for internal dose, individuals with urine pH < 6 had 10-fold higher DNA adduct levels compared to subjects with urine pH > or = 7. As reported previously, polymorphisms in NAT1, NAT2, and GSTM1 had no impact on DNA adduct levels. This is the first study to demonstrate that urine pH has a strong influence on the presence of free urinary aromatic amine compounds and on urothelial cell DNA adduct levels in exposed humans. Because there is evidence that acidic urine has a similar influence on aromatic amines derived from cigarette smoke, urine pH, which is influenced by diet, may be an important susceptibility factor for bladder cancer caused by tobacco in the general population. 相似文献