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121.
Hemodynamic disorders of liver cirrhosis complicated with portal hypertension are associated with an increased angiogenesis in animal model of portal hypertension and cirrhosis which were linked to increased expression of vascular endothelial growth factor (VEGF) and nitric oxide (NO). The aim of study was to evaluate the serum concentration of VEGF and total nitric oxide (NO) in liver cirrhosis and the possible association with the degree of liver insufficiency. VEGF and NO were measured in serum of 64 patients with liver cirrhosis by ELISA and spectrophotometry respectively. The significant increase of serum VEGF was observed in liver cirrhosis compared to healthy individuals as well as serum NO (106.1 ± 66.7 vs. 41.5 ± 6 pg/mL, P < 0.05; 113.5 ± 65.8 vs. 20.8 ± 3.8 μmol/l, P< 0.001, respectively). Serum VEGF and NO showed significant associations with biochemical indices of liver function and with Child-pugh score where they were increased respectively to the degree of liver insufficiency. A significant association of raised serum NO in early stage of portal hypertension reflect its benefit in early expect of portal hypertension but, high serum VEGF in late stage may reflect its prognostic value in liver cirrhosis.  相似文献   
122.
There has been increased awareness of child maltreatment in Saudi Arabia recently. This study assessed the readiness for implementing large-scale evidence-based child maltreatment prevention programs in Saudi Arabia. Key informants, who were key decision makers and senior managers in the field of child maltreatment, were invited to participate in the study. A multidimensional tool, developed by WHO and collaborators from several middle and low income countries, was used to assess 10 dimensions of readiness. A group of experts also gave an objective assessment of the 10 dimensions and key informants’ and experts’ scores were compared. On a scale of 100, the key informants gave a readiness score of 43% for Saudi Arabia to implement large-scale, evidence-based CM prevention programs, and experts gave an overall readiness score of 40%. Both the key informants and experts agreed that 4 of the dimensions (attitudes toward child maltreatment prevention, institutional links and resources, material resources, and human and technical resources) had low readiness scores (<5) each and three dimensions (knowledge of child maltreatment prevention, scientific data on child maltreatment prevention, and will to address child maltreatment problem) had high readiness scores (≥5) each. There was significant disagreement between key informants and experts on the remaining 3 dimensions. Overall, Saudi Arabia has a moderate/fair readiness to implement large-scale child maltreatment prevention programs. Capacity building; strengthening of material resources; and improving institutional links, collaborations, and attitudes toward the child maltreatment problem are required to improve the country's readiness to implement such programs.  相似文献   
123.
This research investigates aspects of epistemic beliefs of pre-service and in-service teachers in the United Arab Emirates, and how these beliefs might be related to factors such as teachers’ gender, location (where they live), and the subject they teach (humanities vs. science). A standardized Arabic version of the Epistemic Belief Inventory was administered to a group of 35 pre-service teachers and 52 in-service teachers. The results indicated that in-service teachers had more sophisticated beliefs than pre-service teachers on Certainty of Knowledge, Omniscient Authority, and Innate Ability dimensions. Also, male teachers were found to be less sophisticated than female teachers and teachers from rural areas tended to think in a simpler way than teachers from urban areas. Although there was no main effect of subject, it significantly modified the effects of gender and location. The data showed the multidimensional nature of epistemic beliefs, and were discussed in the context of Arab/Emirati culture.  相似文献   
124.
提出一种在车辆自组织网络(VANET)中应用的无线多跳视频传输实验系统的设计和实现方案及其对应的传输控制和路由选择协议.该系统将嵌入式Linux与IEEE 802.11n传输协议集成到ARM内核,由S3C6410主控模块、无线局域网网卡及LCD屏等构成.针对VANET的无线多跳视频传输场景,对视频编译码分别采用H.264和JPEG两种标准实现并对它们的压缩比、时延、传输丢包率等性能进行了理论分析和实验比较,进行了室内室外多种不同场景的实际测试.结果表明:所设计的多跳视频传输实验系统方案能够适应VANET等多种场景的应用,所提出的传输控制和路由选择协议能够保证视频传输的多跳和实时性要求.  相似文献   
125.
The case control study was conducted to quantify the amount of the carcinogenic tobacco specific nitrosamine in smokeless tobacco users and smokers in patients with oral leukoplakia and also to emphasize the role of tobacco-specific nitrosamine in the incidence of oral leukoplakia. The study was conducted on 30 patients. The urine samples were obtained from smokeless tobacco users with oral leukoplakia, smokers with oral leukoplakia and non-tobacco users (i.e. people who do not use tobacco in any form). The collected samples were processed by gas chromatography-mass spectrometry. A highly significant difference of NNAL[4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol] in smokeless tobacco users than tobacco smokers P = 0.0002 (Table 1) was obtained. This significant difference shows smokeless tobacco is more carcinogenic than smoked tobacco. This study confirmed that NNAL is a potent biomarker for calculating the risk of occurrence of carcinoma in smokeless tobacco users and smokers, and that smokeless tobacco is more harmful than smoked tobacco.  相似文献   
126.
There has been considerable criticism about the effectiveness and appropriateness of degree courses in engineering over recent years. In part the criticism have related to inadequate preparation for the profession and in part to the traditional methods of teaching. As a reaction to these criticism, attempts were made at one particular technological institution to change the way in which parts of one particular course were taught. The first problem was created by a relatively high failure rate in examinations. In addition, it was felt that problem-solving was an important skill which had been inadequately taught through the conventional lecture course. Previous research had suggested that audiotapes on which students could work and take notes at their own pace might improve the examination results and help with problem-solving skills relevant to the professional engineer. The innovator found evidence for the success of the innovation in terms of a decreased failure rate and his own satisfaction with the changed emphasis in his part of the degree course. However, an independent evaluation based on interviews and observation found that other members of staff, and the students, all held different perceptions of the effectiveness of the innovation. The contrasting perceptions reflected, in part, the extent to which the staff had been involved with the innovation, and the purposes of the students in using the innovative materials and techniques. The study points up difficulties in introducing an innovation into higher education and shows the importance of the very different perceptions held by those who come into contact with the innovation. Implications for understanding the impact of learning environments on student learning, and for the introduction of innovations, are discussed.  相似文献   
127.
The prevalence of hepatitis C virus (HCV) infection varies across the world, with the highest percent of infections reported in Middle East, increasingly in Egypt. The current study aimed at examining the bio-statistical correlation and multiple regression analyses of pituitary growth hormone (GH) and liver activities among HCV genotype-4 patients treated with PEG-IFN-α plus RBV therapy. Herein, the current study was conducted on 100 HCV genotype-4 infected patients and 50 healthy controls. Patients received PEG-IFN-α/RBV for 24 weeks. Host RNA was isolated from patients’ sera for HCV genotyping and viral load determination. Moreover, the enzymatic activities of the liver, AFP, GH, PT, and CBC were performed in all volunteers. The present study resulted that the activities of the hepatic enzymes among HCV genotype-4 patients correlated together significantly. While, human GH showed a significant positive regression with pre-treatment ALT concentration in responders. Furthermore, multiple regression analysis for GH showed a significant positive correlation with pre-treatment ALT in HCV genotype-4 infected patients. We concluded that there were a putative significant relation between GH and pre-treatment ALT activity in HCV infection and response to IFN-based therapy.  相似文献   
128.
ABSTRACT

The study purpose was to use Inertial Measurement Units (IMUs) to objectively assess children’s motor competence in seven movement skills. Fourteen children aged from seven to 12 years (M = 9.64) participated. Children were asked to perform up to 10 trials of each skill. Children performed the skills, which were captured by XSENS MVN Awinda wireless motion capture, and video. Skills were assessed from video as per the criteria from the Test of Gross Motor Development 3. Initially, 17 IMU sensors were used for signal processing, but this was restricted to four sensors (wrists and ankles) to be more feasible for field assessment. Results of the signal testing against its modelled “Good” signal, showed the skip was classified correctly each time, as was the sidestep. Accuracy % rates for each skill were: kick (95.2), catch (95.0), throw (80.5), jump (78.9), and hop (76.9). Using signal processing-based methods via four sensors was a reliable and feasible way to assess seven motor skills in children. This approach means monitoring and assessment of children’s skills can be objective, which will potentially reduce the time involved in motor skill assessment and analysis for research, clinical, sport and education purposes.  相似文献   
129.
130.
The main objective of the current study is to examine the role of the statistical relation between BCL2 gene (Ala43Thr) single nucleotide polymorphism and growth hormone (GH1) levels in Egyptian HCV genotype-4 patients before and after treatment with pegylated interferon plus ribavirin. Eighty patients with HCV genotype-4 and 40 healthy volunteers as controls were enrolled in the prospective study. Gene polymorphism of BCL2 (Ala43Thr) using PCR-RFLP technique and GH1 concentrations using ELISA procedure were measured for all patients and controls. The present study resulted that Responder HCV genotype-4 Patients, with BCL2 43Ala genotype, have high significant increase in pre-treatment GH1 levels (>1 ng/ml); which represent normal levels, as compared to non-responders pre-treatment GH1 levels (<1 ng/ml); which represent low concentrations. We concluded that HCV genotype-4 patients who have normal GH1 concentrations and BCL-2 43Ala genotype can successfully achieve response to interferon based therapy.  相似文献   
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