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This study assessed if students with and without disabilities used calculators (fourfunction, scientific, or graphing) to solve mathematics assessment problems and whether using calculators improved their performance. Participants were sixth and seventh-grade students educated with either National Science Foundation (NSF)-funded or traditional mathematics curriculum materials. Students solved multiple choice and open-ended problems based on items from the State’s released previous assessments. A linear mixed model was conducted for each grade to analyze the factors impacting students’ self-reported calculator use. Chi Square tests were also performed on both grade’s data to determine the relationship between using a calculator and correctly solving problems. Results suggested only time as a main factor impacting calculator use and students who self-reported using a calculator were more likely to answer questions correctly. The results have implications for practice given the controversy over calculator use by students both with and without disabilities.  相似文献   
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Oximes such as pralidoxime chloride reactivate acetylcholinesterase. However their role in management of organophosphate poisoning is controversial. The study was carried out to find effectiveness of pralidoxime chloride (2-PAM) in regenerating red cell acetyl cholinesterase in first 24 h following administration of it in dose recommended by WHO. Eight patients with OPP [chlorpyriphos (3), phorate (3), dichlorvos (1) and monocrotophos (1) who fulfilled the criteria for inclusion were investigated. In addition to decontamination and atropine, all these patients were administered 30 mg/kg body wt of 2-PAM as bolus dose followed by 7.5 mg/kg body wt/h with maximum dose being 500 mg/h as continuous infusion till first 24 h. Red cell AChE activity was estimated every 15 min for first 4 h, one hourly for next 4 h and then 2 hourly till 24 h and subsequently without 2-PAM every 12 h till 7 days or discharge or death which ever earlier. In all the patients maximum increase in activity was observed in first 4 h following which rise was very slow despite continued 2-PAM infusion and reaching a steady state in 20 h in all the cases. The increase in red cell AChE activity observed in diethyl group at 24 h of 2-PAM infusion was 154% vs. 81% in dimethyl group. At 7 days the increase in activity was 215% vs. 118% respectively. However on multiple repeated ANOVA, no statistically significant difference was observed between diethyl and dimethyl groups at admission and discharge (P > 0.05). Similarly no significant difference was observed in three groups when patients were categorized according to WHO classification of organophosphates (P > 0.05). The maximum increase in red cell AChE activity occurs in first 4 h of 2-PAM administration followed by a slow increase despite 2-PAM infusion till 24 h.  相似文献   
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Tuberculosis has, in a short span of time, become a major health problem in the third world or developing countries like India. In view of this, a retrospective study was conducted to study Adenosine deaminase activity in serum and pleural fluid in patients affected with Pulmonary Tuberculosis and other common non-tubercular chronic respiratory diseases. The study was carried out on 100 patients suffering from various pulmonary disorders, between January 2002 and August 2002. Thirty-five normal healthy individuals were included as control subjects. ADA estimation was done by sensitive colorimetric method. The study revealed that the serum ADA activity was higher in patients of tuberculous pulmonary and pleural diseases and non-tuberculous pulmonary diseases than in control subjects. The mean serum ADA activity in the patients’ group was 35.5±6.93 u/l as compared to 16.20±2.85 u/l in control group, showing a highly significant (P≪0.001) difference. ADA activity was highest in tuberculous pleuropulmonary diseases. The pleural fluid ADA activity was higher in pyogenic pleural effusion than in tuberculous pleural effusion.  相似文献   
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It is believed that language is an innate ability and, therefore, spoken language is acquired naturally and informally. In contrast, written language is thought to be an invention and, therefore, has to be learned through formal instruction. An alternate view, however, is that spoken language and written language are two forms of manifestations of the same inner language and that under certain circumstances, they both are acquired the same way. Nevertheless, in reality, the motor mechanisms for speech mature earlier than the ones needed for reading and writing, and, therefore, spoken language gains precedence and is acquired earlier than the written language. Based on this rationale, it is hypothesized that if the option to communicate through oral language is restricted, and children are made to communicate only through written language, we can expect written language skill to emerge with greater force. This hypothesis was put to test by conducting a pilot study in which children’s option to communicate with each other in the classroom was limited to written language for brief periods. One group of fourth graders were allowed to communicate with each other for half an hour a day, 4 days a week, for a period of one semester only through written language. No talking was allowed during this period. A comparison group of children were not restricted in this way. We labeled this project “Drop Everything and Write” (DEAW). Both the groups were administered pre- and post-tests of reading and spelling. After one semester of this program, children in the DEAW program achieved significantly higher scores on tests of vocabulary, reading comprehension, and spelling than the comparison group. The DEAW group also improved greatly in written language use. The results are interpreted to support the hypothesis.  相似文献   
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Gallstones from 24 female patients were subjected to quantitative chemical analysis. Two main categories of stones were identified: (1) Ten cholesterol stones with 93.38% cholesterol and only 0.17% bilirubin. (2) Mixed stones with cholesterol below 65%. They were sub-divided in two groups: (a) Six stones having 0.5% bilirubin and (b) Eight stones having 0.5% bilirubin. The calcium of cholesterol and mixed stones was comparable while phosphorus contents in cholesterol stones were low by over 30% in mixed stones.  相似文献   
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