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71.
Adjuvant effects of saponins on animal immune responses   总被引:2,自引:0,他引:2  
Vaccines require optimal adjuvants including immunopotentiator and delivery systems to offer long term protection from infectious diseases in animals and man. Initially it was believed that adjuvants are responsible for promoting strong and sustainable antibody responses. Now it has been shown that adjuvants influence the isotype and avidity of antibody and also affect the properties of cell-mediated immunity. Mostly oil emulsions, lipopolysaccharides, polymers, saponins, liposomes, cytokines, ISCOMs (immunostimulating complexes), Freund’s complete adjuvant, Freund’s incomplete adjuvant, alums, bacterial toxins etc., are common adjuvants under investigation. Saponin based adjuvants have the ability to stimulate the cell mediated immune system as well as to enhance antibody production and have the advantage that only a low dose is needed for adjuvant activity. In the present study the importance of adjuvants, their role and the effect of saponin in immune system is reviewed.  相似文献   
72.
Seeds of a Chinese traditional medicine plant, Cochinchina momordica were used in the present study for the improvement of influenza vaccine (HSN 1) in chicken. Crude extraction from Cochinchina momordica seed (ECMS) was obtained by ethanol extraction method. In experiment No. 1, two weeks old chickens were immunized with influenza vaccine (HSN1) alone or combined with ECMS (5, 10, 20, 40 and 80 μg/dose). Serum IgG antibody levels (by ELISA) as well as effects on dally weight gain were measured on 0, 7, 14 and 28th day after immunization. Results revealed that all ECMS groups numerically increased the antibody levels while 10 and 20 μg/dose groups significantly (P〈0.05) enhanced total IgG antibody on day 28, when compared with control. Average daily weight gain was also significantly higher in 20 μg/dose ECMS group. Adjuvant effect was also confirmed in experiment No. 2 when chickens were immunized with 20 μg/dose ECMS and antibody titer was measured through hemagglutination inhibition (HI). It is concluded that ECMS has potential to improve the immune responses and deserve further study as an adjuvant.  相似文献   
73.
The objective of this paper is to compare the Jigsaw III technique (of cooperative learning) with the instructional teacher-centered teaching method in six graders in terms of the effect of written expression on their academic success. The universe of the study consists of 71 sixth-grade students studying during 2009–2010 academic term in a primary school in the province of Erzurum. Two classes were randomly selected: one (n = 35) of which was the control group where teacher-centered teaching method was applied, the other being experimental group (n = 36) where the Jigsaw III technique was applied. In the study, one of the most common application, pretest/posttest with control group experimental design, was chosen. The data regarding the academic success of the groups were collected by means of the achievement test in Turkish course as pretest, posttest and retention test; the students’ opinions about the group works were obtained through feedback form, group work opinionnaire, and data were analyzed through 11.5 SPSS program. The results of the statistical analysis of teaching a written expression course showed that the experimental group did significantly better than the control group in terms of academic success. In addition, it can be said that the students had positive impressions on the Jigsaw III technique.  相似文献   
74.
75.
The ability to think analytically and creatively is crucial for success in the modern workforce, particularly for graduate students, who often aim to become physicians or researchers. Analysis of the primary literature provides an excellent opportunity to practice these skills. We describe a course that includes a structured analysis of four research papers from diverse fields of biology and group exercises in proposing experiments that would follow up on these papers. To facilitate a critical approach to primary literature, we included a paper with questionable data interpretation and two papers investigating the same biological question yet reaching opposite conclusions. We report a significant increase in students’ self-efficacy in analyzing data from research papers, evaluating authors’ conclusions, and designing experiments. Using our science-process skills test, we observe a statistically significant increase in students’ ability to propose an experiment that matches the goal of investigation. We also detect gains in interpretation of controls and quantitative analysis of data. No statistically significant changes were observed in questions that tested the skills of interpretation, inference, and evaluation.  相似文献   
76.
This paper deals with the problem of model reference control for linear parameter varying (LPV) systems. The LPV systems under consideration depend on a set of parameters that are bounded and available online. The main contribution of this paper is to design an LPV model reference control scheme for LPV systems whose state-space matrices depend affinely on a set of time-varying parameters that are bounded and available online. The design problem is divided into two subproblems: the design of the coefficient matrices of the controller and the design of the gain of the state feedback controller for LPV systems. The singular value decomposition is used to obtain the coefficient matrices, while the linear matrix inequality methodology is used to obtain the parameter-dependent state feedback gain of the control scheme. A simple numerical example is used to illustrate the proposed design and a coupled-tank process example is used to demonstrate the usefulness and practicality of the proposed design. Simulation and experimental results indicate that the proposed scheme works well.  相似文献   
77.
The purpose of this study was to examine the effect of pretest items on response time in an operational, fixed-length, time-limited computerized adaptive test (CAT). These pretest items are embedded within the CAT, but unlike the operational items, are not tailored to the examinee's ability level. If examinees with higher ability levels need less time to complete these items than do their counterparts with lower ability levels, they will have more time to devote to the operational test questions. Data were from a graduate admissions test that was administered worldwide. Data from both quantitative and verbal sections of the test were considered. For the verbal section, examinees in the lower ability groups spent systematically more time on their pretest items than did those in the higher ability groups, though for the quantitative section the differences were less clear.  相似文献   
78.
A study was carried out to test the effects of a 2-week structured intervention program on academically challenged students’ career development. A quasi-experimental study was designed using pre-tests, post-tests, and a control group approach to examine the effects of the intervention program. Data were collected from both the experimental and control groups. The test was carried out on eight schools in the state of Kedah in Malaysia. Eight school counselors were trained to facilitate the assignment to the experimental groups and to collect data. A total number of 335 students with low academic achievement participated in this study. This number included male (43.6 %) and female (56.4 %) students who were aged 15–16 and a half. Modes of measurement used consisted of a career planning inventory (measuring career planning skills), an academic learning motivation scale (measuring attitude toward academic learning), and an academic study skills test (measuring academic study competencies). Analysis was performed using t-tests and the multivariate analysis of variance to examine the differences in the mean scores. The results show that the sample’s career academic score improved significantly from the pre-test to the post-test. A simple regression analysis was also performed to see the effect of the intervention program on the three dependent variables, which revealed that the career intervention program has positive and significant effects on the three variables. However, further studies on the career program for academically challenged students are highly recommended to support the present study.  相似文献   
79.
Once the COVID-19 was announced as a pandemic by the World Health Organization at the beginning of 2020, almost all countries around the world shifted from traditional face to face education to distance education to prevent the spread of the virus. Türkiye implemented distance education practices through a web-based platform named education information network (EBA) and EBA TV channels. However, the rapid shift from traditional face to face education to distance education was challenging especially for students with disabilities, their parents and teachers because these students needed individualised education and some services which were impossible to implement remotely. The purpose of this study was to explore (a) the challenges that teachers and students faced during distance education; (b) the implications of distance education on students with disabilities. Further, this study explored opinions of special education teachers regarding how to make distance education more effective for students with disabilities. A semi-structured interview was conducted with 12 special education teachers. Findings demonstrated that distance education through EBA was neither sufficient nor convenient for most students with disabilities. Limitations of this study and suggestions for future research were discussed.  相似文献   
80.
Reactive oxygen species, as singlet oxygen (1O2), is continuously being generated by aerobic organisms, and react actively with biomolecules. At excessive amounts, 1O2 induces oxidative stress and shows carcinogenic and toxic effects due to oxidation of lipids, proteins and nucleic acids. In our study, immunoglobulin G (IgG) was modified by 1O2 generated by the ultraviolet (UV) irradiation of methylene blue. The modified IgG was characterized by UV spectroscopy, carbonyl content determination, thermal denaturation and electrophoretic study. Oxidation induced by modification of IgG by 1O2 also analyzed by scavenging studies. It was found that ultraviolet absorption spectra of modified IgG shows marked hyperchromicity. The carbonyl content was found to be high in modified IgG as compared to native IgG which confirms its oxidation. Thermal denaturation of modified protein sample shows decrease in Tm value by 3 °C and less intensity banding pattern on polyacrylamide gel electrophoresis. The quenching effect of sodium azide provides clue for modification of IgG by methylene blue, as it is known 1O2 scavenger. Hence, the IgG modified with 1O2 may be one of the etiological pathogenic factors for rheumatoid arthritis and diabetes.  相似文献   
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