全文获取类型
收费全文 | 196篇 |
免费 | 3篇 |
专业分类
教育 | 134篇 |
科学研究 | 38篇 |
各国文化 | 2篇 |
体育 | 4篇 |
文化理论 | 1篇 |
信息传播 | 20篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 8篇 |
2020年 | 2篇 |
2019年 | 7篇 |
2018年 | 11篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 2篇 |
2014年 | 9篇 |
2013年 | 31篇 |
2012年 | 14篇 |
2011年 | 8篇 |
2010年 | 5篇 |
2009年 | 9篇 |
2008年 | 8篇 |
2007年 | 9篇 |
2006年 | 10篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 6篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有199条查询结果,搜索用时 109 毫秒
61.
Bread wheat varieties as influenced by different nitrogen levels 总被引:4,自引:2,他引:2
INTRODUCTION Dera Ismail Khan lies in Pakistan’s arid zone (71.07° longitude, 31.57° latitude and 500 m above sea level). This zone is in the extreme south of (NWFP) Pakistan at the bank of the River Indus. Dera Ismail Khan is bounded by Sulaiman Range to the West, the Indus River on the East, Marwat and Bhit- tani Ranges on the North and Vehowa Nala (Punjab) on the South. Besides certain local variability the area is comprised of four basic divisions viz mountains, a series … 相似文献
62.
Quality assurance of teacher training has become of a great concern nowadays. This paper addresses the quality of BEd programme of the University of Education (UE) Lahore. The main purpose of the study was to evaluate the quality of BEd programme with regard to the internal efficiency of Government Colleges for Elementary Teachers (GCETs), the affiliated institutions of UE. The study was conducted on a random sample of 600 BEd students drawn from 11 GCETs in Punjab province. Data was collected through a questionnaire which was validated through a pilot study in 2006. The reliability of the final questionnaire was established at 0.863 allowing the researcher to launch the study at large scale (Gay, 2000). The findings revealed that BEd programme was effective in terms of updating student teachers' knowledge and skills. Student teachers favoured the quality of BEd curriculum, lesson planning and presentation by themselves and their teacher educators, and had some reservations about the proper use of audio-visual aids for effective classroom teaching learning processes. Female gender showed more satisfaction with the quality of BEd curriculum and teaching than their male counterparts. No significant difference was found in the opinion of the students of GCETs having low, medium, and high enrolment. 相似文献
63.
64.
65.
Lena Jafri Aysha Habib Khan Saba Azeem 《Indian journal of clinical biochemistry : IJCB》2014,29(3):327-332
To determine the concentration of ionized calcium (iCa) collected in lithium heparin and gel tubes and to correlate the measured iCa with calculated iCa. Anaerobic fasting blood samples were simultaneously collected from healthy laboratory workers in lithium-heparin and gel tubes. iCa, pH, total calcium (CaT), total protein and albumin were measured. Ionized Ca was calculated with albumin and globulin values using an appropriate formula. Mean iCa in gel tubes showed a positive constant bias of 0.08 mmol/L (p < 0.001) when compared to lithium heparin results. The mean pH of blood taken in lithium heparin and gel tubes was non-significant (p = 0.3). Measured iCa poorly correlated with CaT (r = 0.2, p = 0.1) and calculated iCa (r = 0.2, p = 0.2). To evaluate the calcium status direct measurement of iCa must be done rather than using the formulae for iCa determination. In addition serum is recommended as the choice of sample for iCa determination in comparison to plasma samples. 相似文献
66.
67.
Saba Khan Vlach Laura Taylor Melissa Mosley Wetzel 《Pedagogies: An International Journal》2019,14(1):62-77
Many teacher education programs provide teachers with opportunities to read, write, and discuss critical pedagogy, with the hope that such work will allow them to develop more equitable and just teaching practices. Yet, there often remains a gap between the theoretical discussions of teaching and learning in teacher education classrooms and the pedagogical practice in those teachers’ K-12 classrooms. In this study, we examine how one teacher, Gabriela, used narratives to make connections between her third-grade classroom and the critical concepts she was exploring in a teacher education course. Embedded within an ethnographic case study of an inservice teacher education program, we used a discourse analytic approach to examine both the sociocultural knowledge and the identities Gabriela constructed through narrative as she engaged with issues of language, race, and power within the course. We consider some of the affordances of narrative in this space, including how it allowed Gabriela to integrate her understandings of multiple course topics, to position herself in multiple ways as a teacher, and to disrupt her existing understandings of race and racism in the classroom. This analysis suggests that critically oriented teacher education programs might more intentionally make space for narrative to connect critical theory and pedagogical practice. 相似文献
68.
Nadeem Hera Malan Pieter Khan Amir Asif Mohd Ahmad Siddiqui Mansoor Tuhafeni Angombe Simon Ahmad Faheem 《Journal of Zhejiang University. Science. B》2021,22(7):563-574
This study focused, for the first time, on the effect of ultrasonic features on the extraction efficiency of secondary metabolites in mustard seed cake(MSC). The nematostatic potential of sonicated seed cake was examined against the second-stage juveniles(J2 s) of root-knot nematode, Meloidogyne javanica. The results show that a 35 ppm(parts per million) concentration of a sonicated extract(SE) sample of MSC caused 65% J2 s mortality at 18 h exposure period in vitro. It also significantly suppressed the root-knot index(RKI=0.94) in tomato roots. The lethal concentration values for SE were 51.76, 29.79, and 13.34 ppm,respectively, at 6, 12, and 18 h of the exposure period, and the lethal concentration values for the non-sonicated extract(NSE)sample were 116.95, 76.38, and 55.59 ppm, respectively, at similar exposure time. Sinapine and gluconapin were identified as the major compounds in ultrasonic-assisted MSC. Because of the high extraction efficiency of metabolites in the SE, all treatments of SE were shown to be antagonistic to J2 s. Thus, this study of ultrasonication activity-based profiling of MSC may help generate target-based compounds at a scale relevant to the control of disease caused by nematodes in economic crops. 相似文献
69.
Lin Tang Wei-jun Luo Zhen-li He Hanumanth Kumar Gurajala Yasir Hamid Kiran Yasmin Khan Xiao-e Yang 《Journal of Zhejiang University. Science. B》2018,19(2):147-158
Vegetables are important constituents of the human diet. Heavy metals and nitrate are among the major contaminants of vegetables. Consumption of vegetables and fruits with accumulated heavy metals and nitrate has the potential to damage different body organs leading to unwanted effects. Breeding vegetables with low heavy metal and nitrate contaminants is a cost-effective approach. We investigated 38 water spinach genotypes for low Cd and nitrate co-accumulation. Four genotypes, i.e. JXDY, GZQL, XGDB, and B888, were found to have low co-accumulation of Cd (<0.71 mg/kg dry weight) and nitrate (<3100 mg/kg fresh weight) in the edible parts when grown in soils with moderate contamination of both Cd (1.10 mg/kg) and nitrate (235.2 mg/kg). These genotypes should be appropriate with minimized risk to humans who consume them. The Cd levels in the edible parts of water spinach were positively correlated with the concentration of Pb or Zn, but Cd, Pb, or Zn was negatively correlated with P concentration. These results indicate that these three heavy metals may be absorbed into the plant in similar proportions or in combination, minimizing the influx to aerial parts. Increasing P fertilizer application rates appears to prevent heavy metal and nitrate translocation to shoot tissues and the edible parts of water spinach on co-contaminated soils. 相似文献
70.
Theodor Schwann, the German physiologist who first propounded the cell theory with M Schieiden, had diverse interests. He
was not only the first to isolate the enzyme pepsin, but also investigated muscle contraction and nerve structure. In the
mid nineteenth century Schwann discovered that a sheath made up of myelin covered the axons of neurons in the peripheral nervous
system (PNS). The cells that form the myelin are today called Schwann cells after him. Today, we know that the Schwann cells
not only form the myelin sheath around neurons, but also regulate several neuronal functions and are an indispensable part
of the PNS. 相似文献