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71.
The present drinking water purification system in Egypt Uses surface water as a raw water supply without a pre-liminary filtration process.On the other hand,chlorine gas iS added as a disinfectant agent in two steps,pre- and post.chlorination.Due to these reasons most of water treatment plants suffer low fltering effectiveness and produce the trihalomethane (THM) species as a chlorination by-product.The Ismailia Canal represents the most distal downstream of the main Nile Rivet.ThUS its water contains all the proceeded pollutants discharged into the Nile.In addition.the downstream reaches of the canal act as an agricultural drain during the closing period of the High Dam gates in January and February every year.Moreover,the wide in-dustrial zone along the upstream course of the carlal enriches the canal water with high concentrations of heavy metals.The obtained results indicate that the canal gains up to 24.06×106m3 of water from the surrounding shallow aquifer during the closing period ofthe High Dam gates,while during the rest ofthe year,the callal acts as an influent stream losing about 99.6×106m3 of its water budget.The reduction oftotaI organic carbon(TOC) and suspended particulate mattes(SPMs)should be one of the central goals of any treatment plan to avoid the disinfectants by-products.The combination of sedimentation basins.gravel pre-filtration and slow sand filtration,and underground passage with microbiological oxidation-reduction and adsorption criteria showed good removal of parasites and bacteria and complete elimination of TOC.SPM and heavy metals.Moreover,it reduces the use of disinfectants chemicals and lowers the treatment costs.However,this purification system under the arid climate prevailing in Egypt should be tested and modified prior to application.  相似文献   
72.
In this paper the results of a study conducted to determine the perception of counselling needs by primary school teachers in Malaysia and Lesotho are reported. To this end, teachers were asked about the special needs of students they teach, how they cope with these students, what assistance they would like to have in teaching, and the best approach for dealing with student concerns. Teachers in Lesotho are dealing with larger numbers of special needs students and thus are having more difficulties than Malaysian teachers. Malaysian teachers appeared to be more interested in improving their teaching effectiveness. There was some variation in the perceptions of how to best deal with student concerns.  相似文献   
73.
This study investigated the relations among child factors, classroom factors, and the percentage of observations that preschoolers with and without special needs spent in teacher-directed group play. Differences in the number of observations for other types of play (e.g., playing with a teacher or playing cooperatively with peers) between children with and without special needs also was examined. Additionally, the percentage of observations spent by children with and without special needs in different classroom activities and centers was examined. Participants were 48 typically developing children and 22 children with special needs. A scanning method was used to assess play types for the children. Results indicated that girls were more likely to play cooperatively in teacher-directed groups than boys. And, children with special needs were more likely to play with a teacher and less likely to play cooperatively with peers than their typically developing classmates. Children with and without special needs frequently engaged in play in the following areas: art, blocks, science, making food, talking with classmates. In future studies, investigators should observe the different types of child and teacher behaviors related to increased interactions between children who have special needs and their typically developing classmates.  相似文献   
74.
The purpose of this mixed‐methods study was to explore special education teachers’ attitudes towards using technology in inclusive classrooms in Oman. The sample consisted of 428 special education teachers working in Omani public schools (250 teachers of students with learning disabilities (LD), 90 teachers of students with intellectual disability and 88 teachers of students with hearing impairment). Participants responded to the attitudes towards computers questionnaire. For the qualitative section of this study, three semi‐structured group interviews were conducted with a group of special education teachers: 15 teachers of students with hearing impairment, 15 teachers of students with intellectual disabilities and 15 teachers of students with LD). Also, the teachers responded to a survey of educational technology which encompassed seven questions about computer technology. Results of the study indicated that the special education teachers’ attitudes towards using computers were generally positive. The most notable positive attitudes were in the following subscales: special education considerations, staff development considerations, computers use in society, and computers and quality of instruction issues. The analysis of variance results showed that experience and type of disability did not have a significant effect on teachers’ attitudes towards technology.  相似文献   
75.
This study investigated the two different time-of-day effect on team-handball-related short-term maximal physical performances. At two different time-of-day, fifteen young female team handball players performed different physical tests: HandGrip (HG) test, Ball-Throwing Velocity (BTV) test, Modified Agility T-test (MAT) and Repeated Shuttle-Sprint and Jump Ability (RSSJA) test. Rating of perceived exertion (RPE) scale was determined following the termination of the last test. Measurements were performed at two separate testing sessions (i.e., in the morning (7:00–8:30 h) and in the early evening (17:00–18:30 h)) in a randomised and counter-balanced setting on non-consecutive days. The results showed that HG (= 0.0013), BTV (= 0.0027) and MAT (< 0.001) performances were better in the evening compared with the morning. During RSSJA, both best and mean sprint times were shorter in the evening compared to the morning (< 0.001). Moreover, during the latter test, mean jump performance was higher in the evening compared to the morning (= 0.026). However, there was no morning–evening difference in the best jump performance during RSSJA. Likewise, jump performance decrement was not affected by the time-of-day of testing. On the other hand, RPE fluctuated, with morning nadirs and afternoon/early evening highest values. The findings suggest that in female team handball players, team-handball-related short-term maximal physical performances were better in the afternoon than in the morning.  相似文献   
76.
77.
Numerous studies are demonstrating that engaging undergraduate students in original research can improve their achievement in the science, technology, engineering, and mathematics (STEM) fields and increase the likelihood that some of them will decide to pursue careers in these disciplines. Associated with this increased prominence of research in the undergraduate curriculum are greater expectations from funders, colleges, and universities that faculty mentors will help those students, along with their graduate students and postdoctoral fellows, develop an understanding and sense of personal and collective obligation for responsible conduct of science (RCS). This Feature describes an ongoing National Research Council (NRC) project and a recent report about educating faculty members in culturally diverse settings (Middle East/North Africa and Asia) to employ active-learning strategies to engage their students and colleagues deeply in issues related to RCS. The NRC report describes the first phase of this project, which took place in Aqaba and Amman, Jordan, in September 2012 and April 2013, respectively. Here we highlight the findings from that report and our subsequent experience with a similar interactive institute in Kuala Lumpur, Malaysia. Our work provides insights and perspectives for faculty members in the United States as they engage undergraduate and graduate students, as well as postdoctoral fellows, to help them better understand the intricacies of and connections among various components of RCS. Further, our experiences can provide insights for those who may wish to establish “train-the-trainer” programs at their home institutions.  相似文献   
78.
This study assessed the effect of design instructional video based on the Cognitive Theory of Multimedia Learning by applying segmentation and signaling on the learning outcome of students in an online technology integration course. The study assessed the correlation between students’ personal preferences (preferred learning styles and area of specialization) and their learning outcomes. A three-group pretest–posttest design was employed to assess whether there were significant differences in students’ test scores after they watched an instructional video. The results of the analysis of covariance (ANCOVA) analysis indicate that instructional design had a significant effect on students’ learning outcome. This effect was demonstrated by the statistically significant differences in students’ learning outcomes, with the highest scores achieved by students in the segmented and signaled video group and the lowest scores in the no-segmentation and no-signaling group. Moreover, results indicate that students’ learning preferences and area of specialization related significantly and positively to their learning outcomes. These findings suggest that the use of educational video in online courses has the potential to effectively improve students’ learning outcome; however, it requires design manipulation. The results also emphasize the importance of rethinking the one-size-fits-all approach in developing online course content and include consideration of the students’ learning preferences and area of specialization to optimize their learning.  相似文献   
79.
A metabolomic study for determination of certain urinary metabolomes, 1-methyladenosine (1-MA), 1-methylguanosine (1-MG), and 8-hydroxy-2′ deoxyguanosine (8-OHdG) in urine specimens of breast cancer patients. The accuracy of these metabolites and their combined score with cancer antigen 15-3 (CA15-3) was developed to improve the early detection of breast cancer. This study recruited 52 healthy individuals, 47 benign breast tumors, and 167 malignant breast tumor patients. Urine samples were handled to adjust the creatinine concentrations to 8 mg/dL (0.7 mmol/L) and analyzed using GC–MS to detect and quantify the selected urinary metabolomes in urine samples of all participants. The accuracy of individual urinary metabolomes and their combination with CA15-3 were evaluated using multivariate statistical analysis. The cutoff value of CA15-3 was 32.5 U/mL. Cutoff values of 1-MA, 1-MG, and 8-OHdG were 2.19, 2.1, and 7.3 µmol/mmol creatinine, respectively. The concentrations of 1-MA, 1-MG, and 8-OHdG were significantly higher in breast cancer patients, especially in the early-stage. The combination of three urinary metabolomes with CA15-3 improves the diagnostic sensitivity of breast cancer. For the combined score, the area under the curve (AUC) value of combined score ranged from 0.820 to 0.950, with high accuracy, ranged from 77.0 to 95.5%. The most significant AUC (0.973), sensitivity (90.1%), selectivity (94.0%) was recorded at comparing the healthy control with the early-stage of malignant breast cancer. In conclusion, the combination of three urinary metabolomes with serum CA15-3 improves the diagnostic sensitivity of breast cancer.  相似文献   
80.
To examine the possible involvement of human B cell leukemia/lymphoma 2 (Bcl-2), CD4+ cells, hepatocyte growth factor (HGF), and metalloproteinase-9 (MMP-9), as biomarkers in early diagnosis of hepatocellular carcinoma (HCC), activities of these biomarkers in serum were demonstrated by the method of Enzyme Linked Immunosorbant Assay. Two groups of subjects (60 for each), were examined in this study; healthy controls and patients with HCC. The present results declare that, significant decrease in Bcl-2 (p ≤ 0.0001), and CD 4+ (p ≤ 0.001), while significant increase in HGF and MMP-9 (p ≤ 0.05). These findings imply an influence of these biomarkers by the existence of hepatic carcinoma that might reflect the progression of disease and a distinction between the pathological mechanisms involved in hepatic carcinoma. Since, the serum MMP-9 activity was significantly varied between each stage of HCC. An individual profile of the present investigated parameters was detected that might serve as an easy accessing serum marker to monitor the progression of hepatic cell disorders.  相似文献   
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