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101.
Ali Khosrowbeygi Nosratollah Zarghami 《Indian journal of clinical biochemistry : IJCB》2008,23(1):49-52
There is growing evidence that damage to spermatozoa by reactive oxygen species play a key role in male infertility. The aim
of this study was to assess seminal plasma free 8-Isoprostane levels in men with asthenozoospermia, asthenoteratozoospermia
and oligoasthenoteratozoospermia compared to normozoospermic males and its correlation with seminal parameters. The case group
consisted of men with asthenozoospermia (n=15), asthenoteratozoospermia (n=16) and oligoasthenoteratozoospermia (n=15). The
control group consisted of 16 males with normozoospermia. After Purification of Free 8-Isoprostane by affinity column, its
concentration was measured by enzyme immunoassay method. Free 8-Isoprostane evaluation showed significantly greater values
in the total case group (n=46) versus control group (18.23±3.56 vs 2.6±0.38 ng/ml). In each case group free 8-Isoprostane
also showed a significant increasing compared to normozoospermic males. Free 8-Isoprostane showed an inversely significant
correlation with sperm motility and sperm morphology. Lipid peroxidation could have significant role in etiology of sperm
abnormalities. Measurement of 8-Isoprostane can be used as a specific biomarker for assessing lipid peoxidation in sperm. 相似文献
102.
Simsek Hasan Yildirim Ali 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2000,46(3-4):327-342
The data used in this paper were derived from a larger project which had the aim of critically evaluating the Turkish vocational education system on a number of different levels. This article examines the administrative and organisational practices in a selected group of secondary vocational schools in Turkey from the point of view of school administrators, teachers and industrial managers. The results indicate that the Turkish vocational education system is characterised by a centralised, top-down bureaucracy, which inhibits innovative capacity. The authors argue that a degree of decentralisation is necessary at various levels of the system. 相似文献
103.
Pleurotus sajor-caju (Fr.) Singer was cultivated on selected agro wastes viz. cotton stalks, groundnut haulms, soybean straw, pigeon pea stalks and leaves and wheat straw, alone or in combinations. Cotton stalks, pigeon pea stalks and wheat straw alone or in combination were found to be more suitable than groundnut haulms and soybean straw for the cultivation. Organic supplements such as groundnut oilseed cake, gram powder and rice bran not only affected growth parameters but also increased yields. Thus bioconversion of lignocellulosic biomass by P. sajor-caju offers a promising way to convert low quality biomass into an improved human food. 相似文献
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Carbon encapsulated iron nanoparticles(CEINPs) with very thin shells and good core-shell structures were prepared by DC arc discharge at argon intake temperature(AIT) of 800 ℃. The results of high resolution transmission electron microscope(HRTEM), energy dispersive X-ray(EDX) spectroscope, X-ray diffraction(XRD), and X-ray photoelectron spectroscope(XPS) characterizations on the product B show that the thickness of the carbon shells of CEINPs in the product B is in the range of ca. 0.5—5.3 nm, i. e., which can be as thin as only two layers of graphite. The average diameter of the CEINPs is about 24. 7 nm. The total content of Fe element in the product B is 77.0 wt%. The saturation magnetization(Ms) and coercivity(Hc) of the product B are 107.4 emu/g and 143 Oe, respectively. The formation of the CEINPs in the product B is discussed briefly. 相似文献
107.
Ali Bikmoradi Mats Brommels Alireza Shoghli Davoud Khorasani Zavareh Italo Masiello 《Higher Education》2009,57(4):417-427
In Iran, restructuring of medical education and the health care delivery system in 1985 resulted in a rapid shift from elite
to mass education, ultimately leading to an increase in the number of medical schools, faculties, and programs and as well
as some complications. This study aimed to investigate views on academic culture, values, and routines held by faculty members.
A nation-wide survey conducted in six public medical schools in Iran. The research findings show weak organizational culture
and values, together with routine behaviors sensed as a negative and low satisfaction with academic leadership. The research
evidence suggests bureaucracy, politicization, conservativeness, and centralization as common features of medical schools
in Iran and also suggests suitable supervisory skills to tackle the tension between governmental management and academic leadership
with cultural changes, the creation of new values, and adoption more efficient routines. 相似文献
108.
The optimization of cultural conditions for β-glucanase production byBacillus subtilis ZJF-1A5 was investigated in flask trials. Temperature had great effect on β-glucanase production which maximized at optimal
temperature of 37°C and decreased significantly when temperature was over 37°C. Charge quantity affected β-glucanase production
significantly. Adding oxygen vector N-dodecane or acetic ether benefited β-glucanase production, but it depended on the concentration
and charge quantity. The results of fractional factorial design showed that age and size of inoculum and shaking speed were
the key factors affecting β-glucanase production and the cultivation time span to reach the highest β-glucanase activity.
The optimal cultural conditions for β-glucanase production obtained with CCD were as follows: inoculum age and size (16 h,
3.82% (v/v)), shaking speed 210 r/min, charge quantity of 30 mL in 250 mL flask and initial pH 7.0, cultured at 37°C for 50
h. Repeated experimental results accorded with those predicted by a second-order polynomial model. The amount of β-glucanase,
α-amylase and neutral protease produced byB subtilis ZJF-1A5 was associated partially with cell growth. Those three enzymes' activities increased following the cell growth and
increased significantly when cells entered the stationary phase.
Project (No. B0608) supported by the National Natural Science Foundation of China and a grant (2001121B25) from Hangzhou Science
and Technology Development Project of Zhejiang Province, China 相似文献
109.
110.
力学教学对当代大学生的创新能力和素质的培养有着重要的作用.该文结合教学实践和体会,通过力学史的渗透、多种教学手段相结合、“一题多解”的训练、使用力学知识解决生活实际问题和鼓励学生参加课程实践活动等方式,不断激发学生学习兴趣,提高思维积极性,培养创新精神,加强创新能力和科学素质. 相似文献