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71.
Objectives
Recent evidence suggests that suicidal ideation is increased among university students, it is essential to increase our knowledge concerning the etiology of suicidal ideation among university students. This study was conducted to examine the relationships between problem-solving skills appraisal, hardiness, and suicidal ideation among university students. In addition, this study was conducted to examine problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) as a potential mediator between hardiness and suicidal ideation.Methods
The participants consisted of 500 undergraduate students from Malaysian public universities.Results
Structural Equation Modelling (SEM) estimated that undergraduate students with lower hardiness, poor problem-solving confidence, external personal control of emotion, and avoiding style was associated with higher suicidal ideation. Problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) partially mediated the relationship between hardiness and suicidal ideation.Conclusion
These findings underline the importance of studying mediating processes that explain how hardiness affects suicidal ideation. 相似文献72.
Hafedh Makni Jamel Daoud Hanène Ben Salah Nedia Mahfoudh Olfa Haddar Héla Karray Tahya Boudawara Abdelmonême Ghorbel Abdelmajid Khabir Mounir Frikha 《Molecular biology reports》2010,37(5):2533-2539
In order to study the association of HLA-A, -B and/or DRB1, DQB1 and the nasopharyngeal carcinoma (NPC), 141 patients affected
with NPC were typed for the HLA class I by serology method of microlymphocytotoxicity. Among these patients 101 were genotyped
for HLA class II system by the PCR-SSP technique. HLA typing results were compared to those of 116 controls. We found that
the HLA-A31 and -A33 antigens were significantly more expressed in patients than in the controls (P = 0.016 and 0.010, respectively) and the HLA-A19 antigen, was significantly more frequent in patients when compared to the
controls (P = 0.007). The HLA-DRB1*03 and DRB1*13 alleles were significantly more frequent in patients as compared to the controls. The
DRB1*01 allele was expressed with a frequency of 20.69% in the controls whereas it was only detected in 3.96% of the NPC patients.
Furthermore, the DQB1*05 allele was expressed at a frequency which was significantly less important in affected patient (P = 0.03), whereas, the DQB1*02 allele was more frequent in patients (P = 0.643 × 10−4). Thus our study revealed a significant increase of HLA-A31, A33, A19, B16, B53 and DRB1*03, DRB1*13 and DQB1*02 alleles
in our patients. These markers could play a predisposing role in the development of NPC. In contrast, a decrease of HLA-B14,
-B35 and DRB1*01 and DQB1*05 alleles was found suggesting a likely protective effect. 相似文献
73.
Mostafa A. Yehia Tarek S. El-Ammawi Khairia M. Al-Mazidi Mahmoud A. Abu El-Ela Hejab S. Al-Ajmi 《Mycopathologia》2010,169(4):241-246
Background
Fungal infections constitute a major health problem all over the world. Signs and symptoms induced by various dermatophytic infections are difficult to distinguish clinically from each other. So, characterization by in vitro culture is required for appropriate diagnosis and treatment as well as to study the epidemiological characteristics in a region. 相似文献74.
75.
A. E. Abu Khamidakh J. V. Demchuk P. P. Zak M. Lindström M. A. Ostrovsky 《Moscow University Biological Sciences Bulletin》2010,65(2):51-55
Microspectrophotometric measurements of screening granules in Mysis relicta eyes showed that most of the granules have xanthommatin spectra (7nmax 455 nm) with selective absorption of blue light. We calculated spectral sensitivity of M.relicta eyes using screening granules absorption spectra and visual pigment absorption spectra. According to our computations the
calculated spectral sensitivity curve appears to be in a good correspondence with the real spectral sensitivity. 相似文献
76.
Naz Chaibakhsh Mohd Basyaruddin Abdul Rahman Professor Mahiran Basri Abu Bakar Salleh Suraini Abd-Aziz 《Biotechnology journal》2010,5(8):848-855
Dimethyl adipate (DMA) was synthesized by immobilized Candida antarctica lipase B-catalyzed esterification of adipic acid and methanol. To optimize the reaction conditions of ester production, response surface methodology was applied, and the effects of four factors namely, time, temperature, enzyme concentration, and molar ratio of substrates on product synthesis were determined. A statistical model predicted that the maximum conversion yield would be 97.6%, at the optimal conditions of 58.5°C, 54.0 mg enzyme, 358.0 min, and 12:1 molar ratio of methanol to adipic acid. The R2 (0.9769) shows a high correlation between predicted and experimental values. The kinetics of the reaction was also investigated in this study. The reaction was found to obey the ping-pong bi-bi mechanism with methanol inhibition. The kinetic parameters were determined and used to simulate the experimental results. A good quality of fit was observed between the simulated and experimental initial rates. 相似文献
77.
Background
Most of environmental mycobacteria have been previously demonstrated to resist free-living amoeba with subsequent increased virulence and resistance to antibiotics and biocides. The Mycobacterium avium complex (MAC) comprises of environmental organisms that inhabit a wide variety of ecological niches and exhibit a significant degree of genetic variability. We herein studied the intra-ameobal location of all members of the MAC as model organisms for environmental mycobacteria. 相似文献78.
Brian Sheng Xian Teo Mahiran Basri Mohd Rezuwan Shah Zakaria Abu Bakar Salleh Raja Noor Zaliha Raja Abdul Rahman Mohd Basyaruddin Abdul Rahman 《Journal of nanobiotechnology》2010,8(1):4
Background
Cosmeceuticals are cosmetic-pharmaceutical hybrids intended to enhance health and beauty of the skin. Nanocosmeceuticals use nano-sized system for the delivery of active ingredients to the targeted cells for better penetration. In this work, nanoemulsion from palm oil esters was developed as a delivery system to produce nanocosmeceuticals. The stability of the resulting formulation was tested using various methods. In addition, the effect of components i.e. Vitamin E and Pluronic F-68 on the formulation was also studied. 相似文献79.
80.
Time is considered to be an important encoding dimension in olfaction, as neural populations generate odour-specific spatiotemporal responses to constant stimuli. However, during pheromone mediated anemotactic search insects must discriminate specific ratios of blend components from rapidly time varying input. The dynamics intrinsic to olfactory processing and those of naturalistic stimuli can therefore potentially collide, thereby confounding ratiometric information. In this paper we use a computational model of the macroglomerular complex of the insect antennal lobe to study the impact on ratiometric information of this potential collision between network and stimulus dynamics. We show that the model exhibits two different dynamical regimes depending upon the connectivity pattern between inhibitory interneurons (that we refer to as fixed point attractor and limit cycle attractor), which both generate ratio-specific trajectories in the projection neuron output population that are reminiscent of temporal patterning and periodic hyperpolarisation observed in olfactory antennal lobe neurons. We compare the performance of the two corresponding population codes for reporting ratiometric blend information to higher centres of the insect brain. Our key finding is that whilst the dynamically rich limit cycle attractor spatiotemporal code is faster and more efficient in transmitting blend information under certain conditions it is also more prone to interference between network and stimulus dynamics, thus degrading ratiometric information under naturalistic input conditions. Our results suggest that rich intrinsically generated network dynamics can provide a powerful means of encoding multidimensional stimuli with high accuracy and efficiency, but only when isolated from stimulus dynamics. This interference between temporal dynamics of the stimulus and temporal patterns of neural activity constitutes a real challenge that must be successfully solved by the nervous system when faced with naturalistic input. 相似文献