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101.
Cytochrome P450 2C9 (CYP2C9) is involved in metabolism of many important drugs and its genotype variations is thought to affect drug efficacy and the treatment process. The aim of this study was to assess the distribution of CYP2C9 allele and genotypic variants in Sistani ethnic group, living in Gorgan, South East of Caspian Sea and North East of Iran. This study included 140 Sistani, referred to the health center of Gorgan. CYP2C9 genotyping was carried out by polymerase chain reaction–restriction fragment length polymorphism technique. The allele frequency of CYP2C9*1, CYP2C9*2 and CYP2C9*3 was 76.1, 16.1 and 7.8%, respectively. The frequency of CYP2C9*1/*1, CYP2C9*1/*2, CYP2C9*1/*3, CYP2C9*2/*2, CYP2C9*2/*3 and CYP2C9*3/*3 genotypes was 53.9, 22.1, 11.4, 2.9, 4.3% and nil, respectively. In this study the genotypic variations of the CYP2C9 allele among the Sistani ethnic group was investigated and great differences were observed in comparison to other populations. Our findings suggest that different genotypes of CYP2C9 may influence the pharmacokinetics of some drugs. More studies on the pharmacokinetic effects of CYP2C9 genotypes may help physicians choose optimal dosage of some drugs for treatment and prevention of their side effects. Since different ethnic groups from all over the world use medications, it suggests to investigate the pharmacokinetic effects of CYP2C9 genotypes in different populations.  相似文献   
102.
Pre-miRNA-499 gene is associated with autoimmune disease. Mir-449 rs3746444 polymorphism is inconsistent for rheumatoid arthritis (RA). This study aimed to investigate association of mir-499 rs3746444 polymorphism with RA activity and severity in Egyptian population. The study population was conducted as case control study in 100 RA patients diagnosed according to the American College of Rheumatology classification criteria for RA, and the control group included 100 healthy subjects who were age-and sex-matched to the RA group. Different genotypes were assessed using polymerase chain reaction–restriction fragment length polymorphism. 95% Confidence interval and odds ratio were defined to assess the strength of association. Regarding patients, thirty-three patients carried TT genotype, fifty-three patients carried TC genotype and fourteen patients carried CC genotype. So the frequency of the minor C allele in RA patients was significantly higher than the control subjects (P = 0.037). TC, CC genotypes and C allele frequencies were significantly associated with disease severity as they had high rheumatoid factor (55.78 µIU/ml) and anti-cyclic citrullinated peptide (Anti-CCP) antibody (297.32 µIU/ml). Moreover, the heterozygote TC had more severe and more active form of the disease compared with homozygote CC or TT as they had high Anti-CCP antibody, and disease activity score 28 (score 5). Our work suggests that C allele of Pre-miRNA rs3746444 polymorphism contributes to heritability of susceptibility to RA compared to T allele. This polymorphism was associated with the activity and severity of the disease.  相似文献   
103.
In this paper, an adaptive Takagi–Sugeno (T–S) fuzzy controller based on reinforcement learning for controlling the nonlinear dynamical systems is proposed. The parameters of the T–S fuzzy system are learned using the reinforcement learning based on the actor-critic method. This on-line learning algorithm improves the controller performance over the time, which it learns from its own faults through the reinforcement signal from the external environment and tries to reinforce the T–S fuzzy system parameters to converge. The updating parameters are developed using the Lyapunov stability criterion. The proposed controller is faster in learning than the T–S fuzzy that parameters learned using the gradient descent method under the same conditions. Moreover, it is able to handle the load changes and the system uncertainties. The test is carried out based on two mathematical models. In addition, the proposed controller is applied practically for controlling a direct current (DC) shunt machine. The results indicate that the response of the proposed controller has a good performance compared with other controllers.  相似文献   
104.
An adaptive numerical method for solving multi-delay optimal control problems with piecewise constant delay functions is introduced. The proposed method is based on composite pseudospectral method using the well-known Legendre–Gauss–Lobatto points. In this approach, the main problem converts to a mathematical optimization problem whose solution is much more easier than the original one. The necessary conditions of optimality associated to nonlinear piecewise constant delay systems are derived. The method is easy to implement and provides very accurate results.  相似文献   
105.
The main objective of this paper is to drive a rotary inverted pendulum by following a desired navigation instruction. This navigation is commanded by the user through a new electromagnetic device which is allowed to perturb the pendulum from its upright position. This apparatus consists of an electronic magnetic driving circuit to introduce commands and realized via two operated magnetic coils. So, the external programmed magnetic perturbation can be seen as external commandments. Therefore, the control problem statement is solved via a modified regulation control implementation, to maintain the pendulum on its upright position and giving free manipulation of the base of the rotary inverted pendulum. Hence, by using the corresponding H-linear matrix inequality technique, a static state controller is designed and tested experimentally so supporting our findings.  相似文献   
106.
This paper proposes a probabilistic fuzzy proportional - integral (PFPI) controller for controlling uncertain nonlinear systems. Firstly, the probabilistic fuzzy logic system (PFLS) improves the capability of the ordinary fuzzy logic system (FLS) to overcome various uncertainties in the controlled dynamical systems by integrating the probability method into the fuzzy logic system. Moreover, the input/output relationship for the proposed PFPI controller is derived. The resulting structure is equivalent to nonlinear PI controller and the equivalent gains for the proposed PFPI controller are a nonlinear function of input variables. These gains are changed as the input variables changed. The sufficient conditions for the proposed PFPI controller, which achieve the bounded-input bounded-output (BIBO) stability are obtained based on the small gain theorem. Finally, the obtained results indicate that the PFPI controller is able to reduce the effect of the system uncertainties compared with the fuzzy PI (FPI) controller.  相似文献   
107.
In this paper, a method is proposed to reject disturbances in the model predictive control (MPC) strategy. In addition, uncertainties in the system parameters (i.e., internal disturbances) are considered as well. To achieve these goals, adaptive neural networks are designed as the predictor model and as the nonlinear disturbance observer, respectively. The disturbances are rejected via the optimization problem of the MPC. Stability of the closed-loop system is studied based on the Input-to-State Stability method. The proposed method is applied to the pH neutralization process and CSTR system and its effectiveness in optimal rejection of the disturbances and satisfying the system constrains is compared with the feed-forward control method.  相似文献   
108.
This paper addresses the issue of how games can reshape education by describing current educational practices. It argues that there are conservative camps that emphasize structure and development of basic literacy and numeracy skills in education as well as liberal camps that emphasize immersion, and notices that both camps fail to train students able to address the crisis of innovation. A post-progressive pedagogy that integrates both structure and immersion to address this innovation crisis is described in the paper. It is also emphasized that epistemic games can serve as excellent tools at the hand of this post-progressive pedagogy.  相似文献   
109.
Flow cytometry has been employed as a method to study homogeneity of isolated islet subpopulations. After collagenase digestion of rat pancreas and elutriation of tissue fragments, islets were isolated and dissociated, and cells were analyzed and sorted according to their low forward angle light scattering properties by using automated flow cytometry. A standardized procedure was developed for the preparation of rat islet cell grafts for purification of islet cells. In this process, after collagenase digestion of pancreas, islets were isolated, dissociated, identification by dithizone method and then with enzymatic procedure by DNase and trypsin, the islet cells changed into single cells and beta cells were identified by immunofluorescence method and then assayed by flow cytometry. Methods have been developed for the preparation of suspension of viable rat pancreatic islet cells and their analysis and sorting in the fluorescence activated cell sorter (FACC IV, Becton Dickinson, Sunnyvale, Ca). Flow cytometry of these cells indicated that there were 91% of beta cells in cell suspension. Most of the exocrine particles were lost during digestion. Purified endocrine islet cell grafts were prepared by pure beta-cells, without endocrine non-beta cells. The purified aggregates were devoid of endocrine non-beta cells and damaged cells.  相似文献   
110.
Abstract

Cross‐border informal trade is one of the most important issues between India and Bangladesh. It takes place between people who live a short distance apart, but who find themselves separated by an international boundary. The people of international border areas believe that cross‐border informal trade is a process to maintain a sustainable livelihood because it provides a livelihood to the unemployed. This research has analysed the nature and impact of informal border trade between India and Bangladesh. It has highlighted the sources of security and insecurity through the process of informal border trade. It also analyses the different socio‐economic conditions of informal border trade in border trade prone areas. This research argues that although informal border trade is considered illegal, it is necessary for the maintenance of the livelihood for the poor in the bordering areas. The state failures in fulfilling the needs of the poor force them to involve themselves in informal border trade.  相似文献   
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