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151.
152.
Asma Farhat Sherwani Sameena Mohmood Fauzia Khan Rizwan Hasan Khan Md. Asim Azfer 《Indian journal of clinical biochemistry : IJCB》2003,18(2):169-180
Lectins, a group of specific glycoproteins present in animal as well as plant cells, are used as differentiating markers to
study cancers and metastatic cell lines. This property of lectins depends on the process of cellular glycosylation. Glycosylation
of some of the extracellular membrane proteins and lipids maintains the cell/cell and cell/matrix interactions. Chemical alterations
in glycosylation play an important role in the metastatic behavior of tumor cells. Carbohydrate residues of the membrane glycoproteins
can be detected using lectins due to their binding specificity to carbohydrates. Lectins, therefore have gained an importance
in the field of cancer research. Galectins, a specialized group of lectin like proteins that are Ca+ independent and galactoside
binding, are also considered as differentiation markers in some specific cancers like the carcinomas of thyroid.
Thus the use of lectins and galectins to identify specific carbohydrates present on cell surface help in invasion and metastasis
processes. 相似文献
153.
Lian Deng Chao Zhang Kai Yuan Yang Gao Yuwen Pan Xueling Ge Yaoxi He Yuan Yuan Yan Lu Xiaoxi Zhang Hao Chen Haiyi Lou Xiaoji Wang Dongsheng Lu Jiaojiao Liu Lei Tian Qidi Feng Asifullah Khan Yajun Yang Zi-Bing Jin Jian Yang Fan Lu Jia Qu Longli Kang Bing Su Shuhua Xu 《国家科学评论(英文版)》2019,6(6):1201
Human genetic adaptation to high altitudes (>2500 m) has been extensively studied over the last few years, but few functional adaptive genetic variants have been identified, largely owing to the lack of deep-genome sequencing data available to previous studies. Here, we build a list of putative adaptive variants, including 63 missense, 7 loss-of-function, 1,298 evolutionarily conserved variants and 509 expression quantitative traits loci. Notably, the top signal of selection is located in TMEM247, a transmembrane protein-coding gene. The Tibetan version of TMEM247 harbors one high-frequency (76.3%) missense variant, rs116983452 (c.248C > T; p.Ala83Val), with the T allele derived from archaic ancestry and carried by >94% of Tibetans but absent or in low frequencies (<3%) in non-Tibetan populations. The rs116983452-T is strongly and positively correlated with altitude and significantly associated with reduced hemoglobin concentration (p = 5.78 × 10−5), red blood cell count (p = 5.72 × 10−7) and hematocrit (p = 2.57 × 10−6). In particular, TMEM247-rs116983452 shows greater effect size and better predicts the phenotypic outcome than any EPAS1 variants in association with adaptive traits in Tibetans. Modeling the interaction between TMEM247-rs116983452 and EPAS1 variants indicates weak but statistically significant epistatic effects. Our results support that multiple variants may jointly deliver the fitness of the Tibetans on the plateau, where a complex model is needed to elucidate the adaptive evolution mechanism. 相似文献
154.
155.
In the present work, the fruits of four Morus species, namely Morus alba (white mulberry), Morus nigra (black mulberry), Morus laevigata (large white fruit), and Morus laevigata (large black fruit), were analyzed for proximate composition, essential minerals, and antioxidant potentials. For this purpose,
the ripe fruits were collected from the northern regions of Pakistan. The major nutritional components (moisture, ash, lipids,
proteins, fibres, carbohydrates, and total sugar) were found to be in the suitable range along with good computed energy.
Total dry weight, pH, and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g, (3.20±0.07)–(4.78±0.15),
and (0.84±0.40)%–(2.00±0.08)%, respectively. Low riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits, while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71)
mg/100 g fresh weight (FW). The mulberry fruits were rich with regard to the total phenol and alkaloid contents, having values
of (880±7.20)–(1650±12.25) mg/100 g FW and (390±3.22)–(660±5.25) mg/100 g FW, respectively. Sufficient quantities of essential
macro-(K, Ca, Mg, and Na) and micro-(Fe, Zn, and Ni) elements were found in all the fruits. K was the predominant element
with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g, while Ca, Na, and Mg contents were (440±3.21)–(576±7.37),
(260±3.86)–(280±3.50), and (240±3.51)–(360±4.20) mg/100 g, respectivly. The decreasing order of micro-minerals was Fe>Zn>Ni.
The radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with
total phenolic constituents of the respective fruits. Based on the results obtained, mulberry fruits were found to serve as
a potential source of food diet and natural antioxidants. 相似文献
156.
157.
The gap between the educational achievements of the comparatively wealthy and those living in poverty is widening world‐wide, with the associated threat to social cohesion. Twenty‐five years of curriculum reform has largely failed in its objective of providing quality, basic education for all. Arguing that successful innovation requires the participation of willing teachers, and associating this idea with the claim that schools are important for social cohesion, this study surveyed 500 Jordanian elementary teachers about their involvement in a programme of curriculum change and their desire to participate. Twelve key informants were interviewed. The reform has raised the qualifications of teachers and increased male teacher numbers but has neither raised overall standards nor improved truancy rates. Tight central control has failed to engage teachers’ allegiance to the changes. Officials blamed failures on schools; head teachers blamed parents, and teachers criticized a policy that left them mediating a curriculum that lacked relevance and failed to engage pupils. 相似文献
158.
Abdul Mannan Khan S. Mustafa Zaidi Md. Safay Zaffar Bharati 《International Information and Library Review》2013,45(2):71-78
The study is focused on finding out the level of use of on-line databases by faculty members and research scholars of the Jawaharlal Nehru University (JNU) and Jamia Millia Islamia (JMI), Delhi (India). Both are Central Universities and are funded by the University Grants Commission (UGC). A well-structured questionnaire was administered to faculty members and research scholars of the JNU and JMI to collect data regarding the use of on-line database. The survey reveals that all of the faculty members and research scholars are aware of the availability of on-line databases and largely use them for reference purposes in their research work and studies. The degree of usefulness and utilization of on-line databases is high among the universities' faculty members and research scholars. The survey further reveals that the respondents from both universities are aware of the search options for accessing on-line databases. It is also found that a large number of respondents of JNU and JMI are using field searching and Boolean operators to access information from on-line databases. 相似文献
159.
All stakeholders are aware of the importance of measuring performance in higher education at the university/college level. Generally the performance indicators used for this purpose have focused on graduation rates and/or final examination scores, rather than the performance-enabling processes. Further, the most commonly used method for knowledge transfer is the traditional classroom teaching, which should be tracked/monitored continuously during its delivery process. It can help in the detection and correction of existing and impending problems, if any, in the teaching and learning processes. Further, the students’ attitude towards learning, that is, their readiness/willingness and interest should also be taken into consideration while measuring the performance of classroom teaching.
In the present paper, the model for measuring classroom performance illustrated by Grygoryev and Karapertrovic (2005) is used to measure the performance of under-graduate Engineering students in two BTech. (Mechanical) courses, namely, fluid mechaincs (FM) and experimental methods and analysis (EMA). Classroom assessment techniques (CATs) along with the statistical process control (SPC) have been used to analyse the learning performance. Further, the data for student's readiness and interest factors are collected and their positive influences on knowledge gain are established. 相似文献
160.
Anatomy education environment measurement inventory: A valid tool to measure the anatomy learning environment
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Siti Nurma Hanim Hadie Asma' Hassan Zul Izhar Mohd Ismail Mohd Asnizam Asari Aaijaz Ahmed Khan Fazlina Kasim Nurul Aiman Mohd Yusof Husnaida Abdul Manan@Sulong Tg Fatimah Murniwati Tg Muda Wan Nor Arifin Muhamad Saiful Bahri Yusoff 《Anatomical sciences education》2017,10(5):423-432
Students' perceptions of the education environment influence their learning. Ever since the major medical curriculum reform, anatomy education has undergone several changes in terms of its curriculum, teaching modalities, learning resources, and assessment methods. By measuring students' perceptions concerning anatomy education environment, valuable information can be obtained to facilitate improvements in teaching and learning. Hence, it is important to use a valid inventory that specifically measures attributes of the anatomy education environment. In this study, a new 11‐factor, 132‐items Anatomy Education Environment Measurement Inventory (AEEMI) was developed using Delphi technique and was validated in a Malaysian public medical school. The inventory was found to have satisfactory content evidence (scale‐level content validity index [total] = 0.646); good response process evidence (scale‐level face validity index [total] = 0.867); and acceptable to high internal consistency, with the Raykov composite reliability estimates of the six factors are in the range of 0.604–0.876. The best fit model of the AEEMI is achieved with six domains and 25 items (X2 = 415.67, P < 0.001, ChiSq/df = 1.63, RMSEA = 0.045, GFI = 0.905, CFI = 0.937, NFI = 0.854, TLI = 0.926). Hence, AEEMI was proven to have good psychometric properties, and thus could be used to measure the anatomy education environment in Malaysia. A concerted collaboration should be initiated toward developing a valid universal tool that, using the methods outlined in this study, measures the anatomy education environment across different institutions and countries. Anat Sci Educ 10: 423–432. © 2017 American Association of Anatomists. 相似文献