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排序方式: 共有226条查询结果,搜索用时 31 毫秒
21.
Nosratollah Zarghami Mohammad Rohbani-Noubar Ali Khosrowbeygi 《Indian journal of clinical biochemistry : IJCB》2005,20(2):182-185
Pregnancy is associated with significant, but reversible changes in thyroid function studies, which are among the most profound
seen as a result of a normal physiologic state. The present study was carried out to find out alterations in thyroid function
tests in each trimester in normal pregnant women as compared to non-pregnant women in Tabriz-Iran. A case-control study designed
with 229 normal pregnant women that randomly selected from the first (64 samples), the second (92 samples), and the third
(73 samples) trimesters and 250 randomly selected non-pregnant healthy female controls. Age range in both groups was 16–40
years. Thyroid function tests carried out by measuring serum levels of thyroid stimulating hormone (TSH), free and total thyroxin
(FT4, TT4), and free and total triiodothyronine (FT3, TT3) by commercially available radio immunoassay kits. We found that mean TT4 increased progressively during pregnancy. Our study showed increasing in serum levels of TT3 in the second trimester and then declining during the third trimester compared with non-pregnant women. We showed that FT4 strongly decreased during the third trimester. Free T3 showed declining in the second and third trimesters. Mean TSH did not show significant difference in each trimester compared
with non-pregnant women. The thyroid function tests in pregnancy should be interpreted against gestational age-related reference
intervals to avoid mis-interpretation of thyroid function during pregnancy. 相似文献
22.
We report physicochemical characteristics of various kinds of liquid milk commercially available in Pakistan in comparison with those of fresh natural milk from animals. Milk samples were collected from local markets at Peshawar, Pakistan,and analyzed for their physical features, including moisture, total solids, specific gravity, conductivity, viscosity and titratable acidity (lactic acid equivalent), and chemical components and macro-minerals, including total protein, casein, lactose, ash and minerals (Na, K and Mg). These items were compared with the physicochemical characteristics of the fresh natural milk samples from buffalo, cow and goat. The results were also compared with reported nutritional quality of milk from various countries and World Health Organization (WHO) standards. We found that all the physical features and chemical components of commercially available milk in Pakistan markets meet WHO's requirements, except for Na, K, Ca and Mg, which are below the standards. 相似文献
23.
In 1975/76 Kuwait University was transferred to an Elective System and initially, the article reviews the rationale and objectives of such a change. Guidance or advisement is considered a key means to achieve these objectives. The major focus of the article is an examination of several attempts to assess/evaluate the implementation and effectiveness of advisement. Recommendations for practical solutions to those problems which surround this practice are also discussed.Paper submitted to the International Consultation Conference on Career Guidance in Higher Education convened by IRTAC and Robinson College — Cambridge University, 13–17 December 1981, Robinson College, Cambridge, England. 相似文献
24.
In adopting a customer‐oriented approach to higher education, quality function deployment (QFD) is one of the total quality management techniques which can be applied for process and design improvement. Following a review of some practices in this sector, this paper outlines a QFD model in which the opinions of three groups of customers are utilized for quality planning. A developed framework for the dimensions of quality in engineering education was used in conjunction with the quality processes in a departmental quality management framework proposed by the Engineering Professors’ Council. The results from the QFD led to a strategy for prioritizing the different quality processes within a school/department. 相似文献
25.
Navid Vafamand Mohammad Hassan Asemani Alireza Khayatian 《Journal of The Franklin Institute》2017,354(14):5854-5876
In this paper, a novel technique for Takagi–Sugeno (TS) model-based robust L1 controller design of nonlinear systems is proposed. Two synthesis methods based on quadratic and non-quadratic Lyapunov functions are considered. To design the robust stabilizing controller, a new approach for deriving sufficient conditions associated with the L1 performance criterion in terms of strict linear matrix inequality is proposed. This novel technique results in less pre-chosen scalar design variables and calculation burden. Furthermore, deriving the controller synthesis conditions via a non-quadratic Lyapunov function (NQLF) relaxes the obtained conditions. Therefore, the proposed approaches not only efficiently minimize the effect of persistent bounded disturbance, but also are applicable for wider classes of TS systems. Furthermore, some new lemmas are proposed to facilitate strict LMI formulation and to provide more degrees of freedom. Finally, several numerical and practical examples are presented to show the merits of this paper. 相似文献
26.
Internationalization of higher education: Challenges, strategies, policies and programs 总被引:1,自引:0,他引:1
Akbar Zolfaghari Mohammad Shatar Sabran Ali Zolfaghari 《美中教育评论》2009,6(5):1-8,20
In today's changing world, the idea of internationalization of higher education especially in developing countries has been deduced from globalization of education process. The international aspect of higher education is becoming increasingly important, composite, and confusing. The higher education has an effect on the society through policy-making, funding, and planning. The purpose of this paper is to analyze the meaning, definition, importance, necessity, and pre-requisites of internationalization of higher education. This paper also studies the programs and strategies of internationalization of higher education. Key challenges for the future direction of internationalization are identified in this paper. 相似文献
27.
Broadband power line communication (BPLC) is a promising solution to satisfy the growing data rate demands for broadband indoor communication networks. However, the BPLC transmission power spectral density (PSD) is restricted in the very high frequency (VHF) band to avoid harmful interference to the existing wireless services. In this paper, a new hybrid system is proposed utilizing BPLC and cognitive radio over TV white space (TVWS) to enhance the system capacity over BPLC in VHF, forming a VHF TVWS BPLC multiple-input multiple-output (MIMO) system. An iterative precoding algorithm is proposed to satisfy the interference limit at the TV primary user (PU) receiver (Rx) and enhance the ergodic capacity. Moreover, a power allocation algorithm is developed for the MIMO system to achieve the maximum ergodic capacity subject to the average total power constraint and limit of interference to TV PU. Simulation results demonstrate the significant enhancement in the achieved capacity by our proposed system in the VHF band compared to both previous cognitive and hybrid BPLC systems. 相似文献
28.
Social informatics research offers insights into the relationship between information technologies and social contexts. However, the material roles of information technologies, and their interplay with the agentic work of social actors, have not been addressed. Drawing on a field study of 37 mobile knowledge workers, we examine the dual material roles (enabling and constraining) played by information technologies in their work practices. We also investigate how these workers exert agency by fashioning multiple information technologies into a functioning digital assemblage. Although information technologies provide consequential affordances that enable mobilization of work across spaces and times, they simultaneously present design-driven, local, organizational, and temporal technological constraints that require mobile knowledge workers to engage in “configuration work” to make information technologies function effectively. Building on a sociomaterial perspective, we further discuss the interplay of information technologies and work practices enacted by mobile knowledge workers, in which both human and technological agency are materialized. 相似文献
29.
Huda Karajeh Mahmoud Maqableh Lama Rajab Hiba Mohammad Tahani Khatib Nabeel Al-Qirim Ali Tarhini 《Education and Information Technologies》2018,23(5):2073-2090
This study examined impact of a social media networks course on student use of SNSs performance. Moreover, it examined the associations among course design, course materials, learning experiences and a social media networks course. Survey instrument is used to examine the relationships in the proposed model. A total of 380 questionnaires have been collected from students at the University of Jordan who studied the social media networks course. A structural equation modelling approach based on AMOS 20.0 statistical software is used to study the causal relationships and test the hypotheses between the observed and latent constructs in the proposed research model. The analysis results revealed that course materials and learning experiences directly, positively and significantly impacted the social media networks course, which in turn had a significant impact on students’ use social networks sites performance. Course design, however, did not impact the social media networks course. Our findings have important implications as we demonstrated the validity of the joint two different models and provide information about impact of studying social media networks course on students’ academic performance. 相似文献
30.
Pejhman Ghassemi Mohammad Hossein Miranbaygi 《Journal of Zhejiang University. Science. B》2009,10(8):602-608
Measurement of optical properties of skin is an expanding and growing field of research. Recent studies have shown that the
biological tissue, especially skin, changes the polarization state of the incident light. Using this property will enable
the study of abnormalities and diseases that alter not only the light intensity but also its polarization state. In this paper
we report an experimental study for measuring changes of polarization state of the light scattered from a phantom similar
to a sample model of scattering skin. Using the notation of Stokes vector for the polarized light and Mueller matrix for the
sample with its polarization properties, we have shown that some elements of the matrix were particularly sensitive to the
changes of the polarization-altering physical properties of the scatterers within the phantom.
相似文献