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51.
Assessment is the process by which the teacher and the student gain knowledge about student progress. Assessment systems should aim at evaluating the desired learning outcomes. In Melaka Manipal Medical College, (Manipal Campus), Manipal, India, the TEMM model (consisting of 4 assessment methods: Triple Jump Test, essay incorporating critical thinking questions, Multistation Integrated Practical Examination, and multiple choice questions) was introduced to 30 refresher students in the fourth block of the academic year. At the end of the block, a questionnaire was distributed to ask the students to rank the different assessments in the order of their preference with respect to seven items. Analysis of the results showed that not a single type of assessment was ranked highest for all the seven items, proving the earlier observation that a single assessment does not fulfill all aspects of assessment and that there is a need for an evaluating system with multiple ways of assessment.  相似文献   
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An innovative approach for inactivation of Mycoplasma gallisepticum using the hydrophobic photoinduced alkylating probe 1, 5-iodonaphthylazide (INA) is described. Treatment of washed M. gallisepticum mid-exponential culture (0.2 mg cell protein /mL) with INA followed by irradiation with far-ultraviolet light (310–380 nm) completely abolished viability. Transmission electron microscopy showed that the majority of the inactivated M. gallisepticum were comparable in size to intact cells, but that part of the INA-treated M. gallisepticum preparation also contained low density cells and membrane vesicles. Confocal microscopy revealed that untreated M. gallisepticum cells were internalized by chicken red blood cells (c-RBCs), whereas the INA-inactivated cells remained attached to the outer surface of the c-RBCs. INA treatment of M. gallisepticum resulted in a complete inactivation of F0F1 –ATPase and of the L-arginine uptake system, but the cytoplasmatic soluble NADH2 dehydrogenase was only partially affected. Western blot analysis of the lipoprotein fraction showed that the INA-treated M. gallisepticum retained their lipoproteins. Following subcutaneous injection of M. gallisepticum INA-bacterin, 100% and 68.8% of chickens were positive by the rapid serum agglutination test and enzyme-linked immunosorbent assay respectively, 2 weeks post-injection. These data suggest that the photoinducible alkylating agent INA inactivates M. gallisepticum but preserves its surface lipoproteins and thus has the potential to be used as a general approach for the inactivation of mycoplasmas for vaccine development.  相似文献   
53.
The taxonomy of the order Phthiraptera is unstable and still problematic to researchers. Most of the current taxon classifications are mainly based on morphological features. Campanulotes bidentatus belongs to the chewing lice of the Philopteridae family that mostly parasitic on birds. There is a lack of sequence data and phylogenetic analyses on the family Philopteridae. In the current study, C. bidentatus was collected from the domestic pigeon Columba livia and identified morphologically and molecularly based on the mitochondrial cytochrome c oxidase subunit 1 gene (COI). The infection rate of the Campanulotes genus was approximately 58.82% in this study. Phylogenetic analysis based on the mt COI gene was informative for members of Philopteridae and the group taxon genera formed distinct clades. Future studies were recommended using the 16s rRNA to enhance the tree topology and obtain clear differentiation between genera.  相似文献   
54.
The plant Cassia angustifolia belongs to Saudi Arabia, which is one of the native places and now cultured throughout the global countries. Medical care in the Arab world is an essential outlet for medicinal plants, both because they are crucial elements for prophetic medicine and due to their lengthy background in the Middle East. C.angustifolia is one of the medicinal plants used in the Saudi Arabia. The usage of plant extracts for synthesizing nanoparticles is conducive to other biological material, since it avoids the lengthy phase of cell culture maintenance. Silver nanoparticles attract further attention due to their strong conductivity, stability and antimicrobial activity across different metal nanoparticles. The present study was designed in the Saudi C. angustifolia leaves with the zinc synthesis of nanoparticles and its antibacterial ability. The plant extracts of C. angustifolia was used for synthesis of zinc nanoparticles, antimicrobial activities against bacterial strains have been tested along with transmission electron microscope (TEM), UV spectroscopy and antimicrobial activities have been conducted. This study showed that silver ions may be transferred from the plant extract to silver nanoparticles. AgNPs biogenic capacity to antibacterial with lovo cell with IC50 ranged from 33.5 ± 0.2 μg/mL demonstrated strong antibacterial capacity to antibody. The overall absorption value for the extract was between 420 and 440 nm and the color transition to green was the plasma absorption of the AgNPs. TEM results was showed in 200,000 magnification. The uniqueness of the current study is that Cassia angustifolia leaf extract from Saudi Arabia was used to prepare the metallic nanoparticles. Additionally, ZnCl2 may also be used as nanoparticles of mineral salt and zinc, which, since their application has been confirmed, are antimicrobial.  相似文献   
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Widespread vascular endothelial injury is the major mechanism for multiorgan dysfunction in sepsis. Following this process, the permeability of the alveolar capillaries is augmented with subsequent increase in water content and acute respiratory distress syndrome (ARDS). Nevertheless, the role of alveolar epithelium is less known. Therefore, we examined alveolar fluid clearance (AFC) using isolated perfused rat lung model in septic rats without ARDS. Sepsis was induced by ligating and puncturing the cecum with a 21-gauge needle. AFC was examined 24 and 48 h later. The expression of Na-K-ATPase proteins was examined in type II alveolar epithelial cells (ATII) and basolateral membrane (BLM). The rate of AFC in control rats was 0.51 ± 0.02 ml/h (means ± SE) and decreased to 0.3 ± 0.02 and 0.33 ± 0.03 ml/h in 24 and 48 h after sepsis induction, respectively (P < 0.0001). Amiloride, significantly decreased AFC in sepsis; conversely, isoproterenol reversed the inhibitory effect of sepsis. The alveolar-capillary barrier in septic rats was intact; therefore the finding of increased extravascular lung water in early sepsis could be attributed to accumulation of protein-poor fluid. The expression of epithelial sodium channel and Na-K-ATPase proteins in whole ATII cells was not different in both cecal ligation and puncture and control groups; however, the abundance of Na-K-ATPase proteins was significantly decreased in BLMs of ATII cells in sepsis. Early decrease in AFC in remote sepsis is probably related to endocytosis of the Na-K-ATPase proteins from the cell plasma membrane into intracellular pools, with resultant inhibition of active sodium transport in ATII cells.  相似文献   
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Small-molecule CCR5 inhibitors such as vicriviroc (VVC) and maraviroc (MVC) are allosteric modulators that impair HIV-1 entry by stabilizing a CCR5 conformation that the virus recognizes inefficiently. Viruses resistant to these compounds are able to bind the inhibitor-CCR5 complex while also interacting with the free coreceptor. CCR5 also interacts intracellularly with G proteins, as part of its signal transduction functions, and this process alters its conformation. Here we investigated whether the action of VVC against inhibitor-sensitive and -resistant viruses is affected by whether or not CCR5 is coupled to G proteins such as Gαi. Treating CD4+ T cells with pertussis toxin to uncouple the Gαi subunit from CCR5 increased the potency of VVC against the sensitive viruses and revealed that VVC-resistant viruses use the inhibitor-bound form of Gαi-coupled CCR5 more efficiently than they use uncoupled CCR5. Supportive evidence was obtained by expressing a signaling-deficient CCR5 mutant with an impaired ability to bind to G proteins, as well as two constitutively active mutants that activate G proteins in the absence of external stimuli. The implication of these various studies is that the association of intracellular domains of CCR5 with the signaling machinery affects the conformation of the external and transmembrane domains and how they interact with small-molecule inhibitors of HIV-1 entry.  相似文献   
59.
Background & objectivesPolycystic ovary syndrome (PCOS) is the most common endocrinal disorder, and the greatest cause of infertility in women. Despite availability of individual data on impact of multiple endocrinal, reproductive and even metabolic factors in PCOS individuals, the data on the co-existence of BED and depression in PCOS patients with its relationship on the quality of life in Saudi Arabian females is not found. Hence this study is aimed to elucidate the implication of PCOS on eating behaviour, induction of depression and general health quality in Saudi Arabian population of Riyadh.Materials and methodsThis is a cross-sectional study carried out in multiple health facilities of Riyadh from January to March 2019. The study samples (494) were recruited by convenience sampling and administered validated questionnaire by trained research participants. The data obtained was analysed by binary logistic regression using SPSS-IBM 25.ResultsOf the total 494 women participated in the study, 23.48% (116) were PCOS individuals. The odds of developing abnormal health related quality of (HRQ) in patients with PCOS was significantly (P = 0.000, OR = 3.472) high when compared to non-PCOS participants. The odds of showing high binge eating disorder (BED, P = 0.007, OR = 2.856) and depression (P = 0.000, OR = 2.497) scores in PCOS participants were significantly more than patients who were not having PCOS. Out of the three parameters studied, abnormal health related quality of life possessed a higher influence of PCOS compared to depression and abnormal eating behavior.Interpretation & conclusionIn conclusion, the present study shows that women with PCOS are at a significant risk for depressive disorders, disorganized eating behavior and impaired quality of life. Therefore, necessary care and screening is required to minimize the impact of PCOS on already burdened individuals.  相似文献   
60.
International Journal of Peptide Research and Therapeutics - Many recent studies have shown the benefits of scorpion venom, as it components may be used as potential candidates for drug...  相似文献   
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