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1.
Over the course of past few years, cancer immunotherapy has been accompanied with promising results. However, preliminary investigations with respect to immunotherapy concentrated mostly on targeting the immune checkpoints, nowadays, emerge as the most efficient strategy to raise beneficial antitumor immune responses. Programmed cell death protein 1 (PD-1) plays an important role in subsiding immune responses and promoting self-tolerance through suppressing the activity of T cells and promoting differentiation of regulatory T cells. PD-1 is considered as an immune checkpoint and protects against autoimmune responses through both induction of apoptosis in antigen-specific T cells and inhibiting apoptosis in regulatory T cells. Several clinical trials exerting PD-1 monoclonal antibodies as well as other immune-checkpoint blockades have had prosperous outcomes and opened new horizons in tumor immunotherapy. Nonetheless, a bulk of patients have failed to respond to these newly emerging immune-based approach and the survival rate was not satisfying. Additional strategies, especially combination therapies, has been initiated and been further promising. Attempts to identify novel and well-suited predictive biomarkers are also sensed. In this review, the promotion of cancer immunotherapy targeting PD-1 immunoinhibitory pathway is discussed.  相似文献   
2.
The rapid and sensitive determination of riboflavin (RF) is important for the treatment of seborrheic and glossitis dermatitis, sunlight sensitivity, mucosal, and skin disorders. In this work, an electrochemical sensor was developed by electrodes modification using poly (chitosan) to sensitive detection of RF in commercial multivitamin. Electrodeposition of chitosan on the surface of glass carbon electrode was performed using cyclic voltammetry technique in the range of ?1 to +1 V. The modified electrode surface morphology was characterized using a high‐resolution field emission scanning electron microscope. The modified electrode was used as an effective electrical interface for the detection of RF using cyclic, differential pulse, and square wave voltammetry techniques. Finally, the sensor was applied to determine RF in commercial multivitamins. In optimum conditions, the linear range for the standard sample of RF and commercial multivitamins 94 to 333μM and 24.6 to 176μM were obtained, respectively. Low limit of quantification (LLOQ) were obtained as 24.6μM.  相似文献   
3.

Testing and developing nutrient diagnosis methods, which can result in the optimum production of fruits, is of significance. The nutritional balance and requirements of almond (Prunus sp.) orchards, in the city of Saman (province of Chaharmahal and Bakhtiari, Iran, one of the biggest producers of almond in the country), were investigated using the methods of diagnosis and recommendation integrated system (DRIS) and deviation from optimum percentage (DOP) in a two-year research. Using 36 gardens along the Zayandehrud River in a 60-km distance, soil physical and chemical properties, as well as leaf micro- and macro-nutrient contents were determined. Similar plant samples (leaf + petiole) in terms of age, genotype and rootstock were collected from the unfruitful trees. The most deficient nutrients including S, Cu, Zn and Mn were indicated by the DRIS and DOP methods. However, according to the DRIS method Mg, and according to the DOP method N, K and Mg were determined as the most excessive macronutrients. Interestingly, both methods indicated Mo as the most excessive micronutrient. The balance indexes of different nutrients for different orchards indicated that the nutritional balances of the orchards from the highest to the least deficiency are according to the following order Cu > S > Zn > Mn > Cl > P > Ca > Mg > B > N > K > Fe > Mo. Such results indicate the precisions and some similarities between the two methods. However, the two methods were compared using SAS Proc GLM, Proc REG, and Proc NLIN. The analyses indicated that the two methods were significantly different and the DOP method (significant model) indicated higher correlation with the results. Accordingly, the DOP method may be a more accurate method of estimating almond yield as affected by the concentration of different nutrients. It is possible to determine the deficiency, balance and excessiveness of nutrients in almond orchards using the DRIS and DOP methods, which is of economic and environmental significance, worldwide.

  相似文献   
4.
Apathya is a lacertid genus occurring mainly in south-east Turkey and its adjacent regions (part of Iran and Iraq). So far two morphological species have been attributed to the genus; A. cappadocica (with five subspecies, A. c. cappadocica, A. c. muhtari, A. c. schmidtlerorum, A. c. urmiana and A. c. wolteri) and A. yassujica. The first species occupies most of the genus’ distribution range, while A. yassujica is endemic of the Zagros Mountains. Here, we explored Apathya’s taxonomy and investigated the evolutionary history of the species by employing phylogenetic and phylogeographic approaches and using both mitochondrial (mtDNA) and nuclear markers. The phylogenetic relationships and the genetic distances retrieved, revealed that Apathya is a highly variable genus, which parallels its high morphological variation. Such levels of morphological and genetic differentiation often exceed those between species of other Lacertini genera that are already treated as full species, suggesting the necessity for a taxonomic revision of Apathya. The phylogeographical scenario emerging from the genetic data suggests that the present distribution of the genus was determined by a combination of dispersal and vicariance events between Anatolia and Southwest Asia dating back to the Miocene and continuing up to the Pleistocene. Key geological events for the understanding of the phylogeography of the genus are the movement of the Arabian plate that led to the configuration of Middle East (orogenesis of the mountain ranges of Turkey and Iran) and the formation of Anatolian Diagonal.  相似文献   
5.
Hydrobiologia - Many populations of Caspian Sea trout (Salmo caspius)—a nationally endangered species in Iran—have been extirpated or depleted due to anthropogenic impacts. The Lar...  相似文献   
6.
Development and activation of B cells quickly became clear after identifying new ligands and receptors in the tumor necrosis factor superfamily. B cell–activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are the members of membrane proteins Type 2 family released by proteolytic cleavage of furin to form active, soluble homotrimers. Except for B cells, ligands are expressed by all such immune cells like T cells, dendritic cells, monocytes, and macrophages. BAFF and APRIL have two common receptors, namely TNFR homolog transmembrane activator and Ca2+ modulator and CAML interactor (TACI) and B cell–maturation antigen. BAFF alone can also be coupled with a third receptor called BAFFR (also called BR3 or BLyS Receptor). These receptors are often expressed by immune cells in the B-cell lineage. The binding of BAFF or APRIL to their receptors supports B cells differentiation and proliferation, immunoglobulin production and the upregulation of B cell–effector molecules expression. It is possible that the overexpression of BAFF and APRIL contributes to the pathogenesis of autoimmune diseases. In BAFF transgenic mice, there is a pseudo-autoimmune manifestation, which is associated with an increase in B-lymphocytes, hyperglobulinemia, anti-single stranded DNA, and anti-double-stranded DNA antibodies, and immune complexes in their peripheral blood. Furthermore, overexpressing BAFF augments the number of peripheral B220+ B cells with a normal proliferation rate, high levels of Bcl2, and prolonged survival and hyperactivity. Therefore, in this review article, we studied BAFF and APRIL as important mediators in B-cell and discussed their role in rheumatoid arthritis.  相似文献   
7.
Dimethyl fumarate (DMF) is an important oral treatment option for various autoimmune diseases, such as multiple sclerosis (MS) and psoriasis. DMF and its dynamic metabolite, monomethyl fumarate (MMF) are the major compounds that exert therapeutic effects on several pathologic conditions in part, through downregulation of immune responses. The exact mechanism of DMF is yet to be fully understood even though its beneficial effects on the immune system are extensively studied. It has been shown that DMF/MMF can affect various immune cells, which can get involved in both the naive and adaptive immune systems, such as T cells, B cells, dendritic cells, macrophages, neutrophils, and natural killer cells. It is suggested that DMF/MMF may exert their effect on immune cells through inhibition of nuclear factor-κB translocation, upregulation of nuclear factor erythroid-derived 2(E2)-related factor antioxidant pathway, and activation of hydroxyl carboxylic acid receptor 2. In this review, the mechanisms underlying the modulatory functions of DMF or MMF on the main immune cell populations involved in the immunopathogenesis of MS are discussed.  相似文献   
8.
MicroRNAs (miRNAs) regulate several biological and physiological processes in mammalian cells, including cellular proliferation, differentiation, apoptosis, and metabolism. Recent studies have confirmed the alteration of them during the cancer development. Matrix metalloproteinases (MMPs), belonging to the large family of proteases, have also been demonstrated to play crucial roles in tissue remodeling, and to support cancer progression and metastasis. There are several known miRNAs which regulate the MMP family and their expression. The expression profiles of miRNAs involved in MMP regulation, change during cancer progression, and metastasis. The present review focuses on important miRNAs capable of targeting MMPs through direct and indirect interactions during the breast cancer development, progression, and metastasis.  相似文献   
9.
Prostate cancer (PCa) is considered the most prevalent malignancy and the second major cause of cancer-related death in males from Western countries. PCa exhibits variable clinical pictures, ranging from dormant to highly metastatic cancer. PCa suffers from poor prognosis and diagnosis markers, and novel biomarkers are required to define disease stages and to design appropriate therapeutic approach by considering the possible genomic and epigenomic differences. MicroRNAs (miRNAs) comprise a class of small noncoding RNAs, which have remarkable functions in cell formation, differentiation, and cancer development and contribute in these processes through controlling the expressions of protein-coding genes by repressing translation or breaking down the messenger RNA in a sequence-specific method. miRNAs in cancer are able to reflect informative data about the current status of disease and this might benefit PCa prognosis and diagnosis since that is concerned to PCa patients and we intend to highlight it in this paper.  相似文献   
10.
Defining the cellular composition of the memory T cell pool has been complicated by an inability to distinguish effector and memory T cells. We present here an activation profile assay, using anti-CD3 and antigenic stimuli, that clearly distinguishes effector and memory CD4 T cells and defines subsets of long-lived memory CD4 T cells based on CD62 ligand (CD62L) expression. The CD62L(low) memory subset functionally resembles effector cells, exhibiting hyper-responsiveness to antigenic and anti-CD3 mediated stimuli, high proliferative capacity, and rapid activation kinetics. The CD62L(high) memory subset functionally resembles resting memory cells, exhibiting hyporesponsiveness to anti-CD3 stimuli, lower proliferative capacity, and slower activation kinetics. Our results indicate that the memory CD4 T cell pool is heterogeneous, consisting of persisting effectors and resting memory T cells.  相似文献   
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